# Why do USB cables make such a difference?



## Cartma (Jul 17, 2017)

As with everything, you start out as a skeptic and with an open mind you are able to stumble across pieces of equipment that you can't believe you went with-out.
After trying a few USB cables I came across the Nordost Blue Heaven USB. This was the first USB cable that actually made an improvement in my system instead of just sounding slightly different. I then decided to go all out and get the next step up.. the Nordost Heimdall 2 USB. This thing made as much, if not more of an improvement then a power cable or interconnect. But the question is WHY?


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## artpiggo

I don't know what I have been heard is wrong or not. please correct me if I misunderstand the concept.

I have been explained that when data transfer, it comes in form of electricity (voltage,current) inside the cable. (It is not exactly 010101 inside cable but it represents in electricity form)

Thus, when current passes through wire, it creates electro-magnetic (Right-handed rule) and if the cable's insulator is not good enough to protect interference each other, there will be so-call digital jitter through data transfer to DAC. As you know Cable Protocol for DAC is USB Audio 1.0 that means it doesn't have File Data Check whether the receiver get the same input or not. (It is like music streaming)






You can see that this cable separate 5V power wire out from the data transfer cable as well. And they seems to use solid insulator to minimize jitters (which is what they claim in their website.)


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## Cartma

I tried the WireWorld Ultraviolet 7 which had a separate isolated power line, didn't hear much of an improvement. There's something about Nordost's approach that make it ideal as a USB cable.


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## Whitigir (Jul 24, 2017)

I have made many USB cables myself, and I will chime in here.  USB cables do bring improvements, and yes, it is even more than powercord...depends on what, how, who made it....but they are all playing a very big part of the whole system.

If you have mid-tier to lower level of system, you may not hear and observe those changes or improvements.  However, there are obvious improvements to observe with high-end systems.

USB cables in music application simply speaking on another hand is mimicking analog waves, and will affect how it will carry out the performances.

Virtually, everything will affect the sound performances.  The higher-end and more revealing the systems, the more it reveal to you in observable ways.  Everything mass produced will come with standard things to make it "tick and tock" in order to maximize profit and sales.....stock cables and so on.



Cartma said:


> I tried the WireWorld Ultraviolet 7 which had a separate isolated power line, didn't hear much of an improvement. There's something about Nordost's approach that make it ideal as a USB cable.



Not sure how your wireWorld were made...aka, materials and geometry wise.  But there are much differences between materials of wires....silver, copper, hybrid...etc...etc...just as much as headphone cables.  Though, the majority of people are still in denial and resist the urge to try Upgraded USB cables out, so the market is small, and hence the prices are super expensive to have great USB cables, and limited options.  However, to many DIY people, the upgraded USB cables improvements are real, and as firm as fact.


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## Jazmanaut

Hmmm...
http://archimago.blogspot.fi/2013/04/measurements-usb-cables-for-dacs.html


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## Whitigir

Jazmanaut said:


> Hmmm...
> http://archimago.blogspot.fi/2013/04/measurements-usb-cables-for-dacs.html


What a waste of my time....none of those cables are audiophile grade to the least......well, kudos to the guys that spent time on it, but he failed.  Keep believing that USB cables don't make the differences, honestly, it saves you money


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## Cartma

Well, I didn't waste my time with that link.


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## Currawong

It's not jitter, but electrical noise.


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## Cartma

The generic USB and other higher end USB cables just sound obnoxious with strident dynamics. The Nordost sound more controlled and mellow. Generic cables just sound dirty in comparison.


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## gregorio

Cartma said:


> The generic USB and other higher end USB cables just sound obnoxious with strident dynamics.



USB cables do not carry any sound and therefore cannot "sound obnoxious". That doesn't mean you can't perceive differences between USB cables, it just means that the reason a USB cable might sound better than another perfectly functioning USB cable is nothing to do with the cable's performance.

G


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## Cartma

gregorio said:


> USB cables do not carry any sound and therefore cannot "sound obnoxious". That doesn't mean you can't perceive differences between USB cables, it just means that the reason a USB cable might sound better than another perfectly functioning USB cable is nothing to do with the cable's performance.
> 
> G



They sure do sound different and other generic cables do sound obnoxious.


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## Currawong

I prefer to say "The sound with [my gear list] when using Cable X versus a generic USB cable seemed to me to be better."


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## gregorio

Cartma said:


> They sure do sound different and other generic cables do sound obnoxious.



I agree with Currawong. You personally might be perceiving an audiophile USB cable as sounding different and generic cables as sounding obnoxious but that doesn't mean that they "sure do sound different", especially as USB cables are not carrying any sound in the first place!

G


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## Whitigir

No cables carry sounds, they carry signals only


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## Currawong

And noise, which is where I think the issue has been. Supposedly Schiit Audio's new Eitr solves that by using ethernet isolation transformers to block it.


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## Speedskater

The differences are probably due to poorly designed connected components.
That was true about two decades ago.  S/PDIF cables were said to sound different, but the cause was (again) poorly designed output and input stages.


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## gregorio

Whitigir said:


> No cables carry sounds, they carry signals only





Currawong said:


> And noise, which is where I think the issue has been.



True but they don't carry analogue signals and therefore noise does not affect the sound.

G


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## Currawong

There's at least one measurement device that has measurements showing the effect of USB noise on the analog components. The noise is independent of the kind of signal being sent through the components, just as a ground loop hum can be. How it can affect the behaviour of digital equipment is worth discussion with people who design it.  I don't think it is fair to make general comments that equipment has been "badly designed" (or even "well designed") when discussing these matters unless we have been making equipment ourselves.  Remember that the Wyrd, and subsequently the Eitr, come from highly experienced and competent designers who were wyrd-ly surprised by their experiments and their results, having previously thought that the USB they had designed was good enough.


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## gregorio

Currawong said:


> [1] How it can affect the behaviour of digital equipment is worth discussion with people who design it.
> [2] I don't think it is fair to make general comments that equipment has been "badly designed" (or even "well designed") when discussing these matters unless we have been making equipment ourselves.
> [3] Remember that the Wyrd, and subsequently the Eitr, come from highly experienced and competent designers who were wyrd-ly surprised by their experiments and their results, having previously thought that the USB they had designed was good enough.



1. The signal and power are specified as part of the USB specifications. We shouldn't need to discuss with the designers the behaviour of a USB DAC being supplied with a standard USB signal. And, owners shouldn't have to go and buy non-standard cables (or other devices) to get a USB DAC to function correctly with a standard USB signal.

2. I can't agree with this, either in respect to audiophile manufacturers or manufacturers of any other type of product. Surely a USB DAC (or any other USB device) should operate flawlessly with a standard USB signal, otherwise how is it honestly a "USB" DAC? Why shouldn't the quality of the engineering design be commented upon? Are audiophiles really only interested in the appearance and marketing of the equipment, does the actual performance not matter in the least? Maybe this is the wrong sub forum to ask such questions? 

3. Competent designers would have done those "experiments and results" BEFORE releasing the product, rather than effectively releasing an under tested/faulty product, then designing a new product with the faults fixed and not offering that fix to the purchasers of the original faulty product. This does not appear to be an uncommon scenario in the audiophile market, we even see it sometimes in the pro audio market, although typically only from some of the small, boutique manufacturers. 

Have we ascertained is the OP actually has such a defective DAC? Even if he does, how would a "Nordost Blue Heaven USB" cable be an improvement over say an Amazon Basics USB cable AND, how would a "Nordost Heimdall 2 USB" cable be such an improvement over both?

G


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## Cartma

gregorio said:


> how would a "Nordost Blue Heaven USB" cable be an improvement over say an Amazon Basics USB cable AND, how would a "Nordost Heimdall 2 USB" cable be such an improvement over both?



I don't know gregorio, you tell me. There must be allot of poorly designed DACs out there considering every DAC I've tried the cable on sounded better. Have you even tried a high end USB cable before?


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## gregorio

Cartma said:


> [1] I don't know gregorio, you tell me.
> [2] There must be allot of poorly designed DACs out there considering every DAC I've tried the cable on sounded better.
> [3] Have you even tried a high end USB cable before?



1. I can't, beyond the obvious biases there is no other rational explanation.
2. Not in my experience, incredibly few in fact. Although, there do seem to be quite a few audiophiles with DACs which apparently require some sort of additional equipment in order to function optimally.
3. Yes, if you mean an audiophile USB cable, although it didn't belong to me. I prefer to stick to high end, non-audiophile cables though.

G


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## Puma Cat (Aug 5, 2017)

Thats what better cables do, preserve signal integrity and minimize the impact of noise.

I used think that a power cord couldn't make a difference, then I bought two Shunyata power cables and discovered that I was completely wrong, and in a rather dramatic way.

When I got into computer audio, I also didn't think a USB cable could make a difference, the old 'bits is bits' thang, but..._they do_. Wrong again. An an Audioquest Diamond USB sounds considerably better than an Audioquest Carbon USB.

I'm a scientist, I just go by what the data tells me, and controlled experiments tell me these cable make a difference. Just as better power supplies do.


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## Whitigir (Aug 5, 2017)

Puma Cat said:


> Thats what better cables do, preserve signal integrity and minimize the impact of noise.
> 
> I used think that a power cord couldn't make a difference, then I bought two Shunyata power cables and discovered that I was completely wrong, and in a rather dramatic way.
> 
> ...


It is futile to try and convince the folks that cables do make differences.  It is more conveniences to find the negativities about these cables and just buy a cheaper and more affordable one and thinking that it makes 0 differences.  Really is futile to try and convince them.  Not to mentions that many people "thought" that they are technically advanced and "believe" that they know many many things about these cables with just "googling skills."

I make my cables, and they all make the differences, be it USB cables, or Headphones cables.


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## Puma Cat (Aug 5, 2017)

Whitigir said:


> It is futile to try and convince the folks that cables do make differences.  It is more conveniences to find the negativities about these cables and just buy a cheaper and more affordable one and thinking that it makes 0 differences.  Really is futile to try and convince them.  Not to mentions that many people "thought" that they are technically advanced and "believe" that they know many many things about these cables with just "googling skills."
> 
> I make my cables, and they all make the differences, be it USB cables, or Headphones cables.



Yeah, I know. I made some fun of this once when I posted a picture in Steve Hoffman forums using one of my Shunyata Black Mamba power cables connected to my VPI record cleaning machine, claiming that using it results in notable improvements in the form of _less noise and "blacker blacks"_ (i.e., cleaner records! LOL.) Some folks thought I was actually serious.

I was skeptical about power cords for a long time; then I read Cealin Gabriel of Shunyata Research's actual patents on cable design and using Rochelle salts for RFI and EM noise rejection. And found out that he used to work for the NSA for 25 years in "signals intelligence" signals processing and figured trying a couple of power cables out that I bought for a 50% discount in a controlled experiment would be worth a shot, given that they were designed by someone who _actually knew what he was doing_. Been using Shunyata products ever since...


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## chef8489

Whitigir said:


> It is futile to try and convince the folks that cables do make differences.  It is more conveniences to find the negativities about these cables and just buy a cheaper and more affordable one and thinking that it makes 0 differences.  Really is futile to try and convince them.  Not to mentions that many people "thought" that they are technically advanced and "believe" that they know many many things about these cables with just "googling skills."
> 
> I make my cables, and they all make the differences, be it USB cables, or Headphones cables.


Or maybe many of us have been down the cable rabbit hole and tested them, had labs test them, and proven it is a bunch of rubbish and placebo. We have been at this a long time.  Anyhow this really needs to be in sound science sub and not this one.


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## Whitigir

You all know that Silver is more conductive than Copper ? And it is 5% more.  So...tell me.....can it make the differences ?  What is a "tolerances" rating in electrical components ? 10% tolerances vs 5% ?  Never mind......i don't know what I am talking about....do you ?


chef8489 said:


> Or maybe many of us have been down the cable rabbit hole and tested them, had labs test them, and proven it is a bunch of rubbish and placebo. We have been at this a long time.  Anyhow this really needs to be in sound science sub and not this one.


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## chef8489

Whitigir said:


> You all know that Silver is more conductive than Copper ? And it is 5% more.  So...tell me.....can it make the differences ?  What is a "tolerances" rating in electrical components ? 10% tolerances vs 5% ?  Never mind......i don't know what I am talking about....do you ?


In an analogue cable yes. It can change the sound. In a digital cable. No it can not change the sound.


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## Speedskater

Whitigir said:


> You all know that Silver is more conductive than Copper ? And it is 5% more.  So...tell me.....can it make the differences ?  What is a "tolerances" rating in electrical components ? 10% tolerances vs 5% ?  Never mind......i don't know what I am talking about....do you ?


It's 5% more conductive when the conductor's cross-section are exactly the same. Does it matter if the cables are 100 inches or 105 inches long? Of course not!

In interconnect cables conductivity does not change the sound. Be it the shield, low conductivity can add background noise.


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## Currawong

The manufacturers I've spoken to, two of whom have posted here about it, thought that their USB implementations were good enough until they either did experiments themselves (with electronics, not cables) and/or had feedback from customers that they could be better.


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## bixby (Aug 5, 2017)

I have been down this rabbit hole and popped out the other side.  Needless to say to those in the know, but a USB cable designed to the specs required by USB.org and built to meet those specs is usually just fine.  Problem is lots and lots of USB cables do not meet the design specs when they are made.  Slight errors in manufacture can cause the transmission spec to not be met. 

An article a few years back found that a majority (not sure if it was 75-80% but it was high) of the usb cables they tested did not meet spec.  My guess is lots of the differences in bespoke cables vs run of the mill  types is due to how well they are made. 

Shielding is important and often times can affect the audible differences we hear.  I know placing a ferrite on a cable in my enviornoment usually helps.  Placing several cause the highs to go too soft.  I am not a physicist but engineers might point to rfi or emil hopping on and riding the signal all the way to receiver and decoding chips. 

All I know is I have purchased a bunch of the upper crust USB cables only to challenge myself to really listen and pick a winner.  Anyone want a good price on a short Wireworld USB?

Here is my favorite usb cable and one which is used in all 3 of my computer based audio systems.  It sounds as good as any of the fancy cables.

Good reading:
http://www.7ms.com/enr/online/2010/02/notebook.shtml

http://www.ti.com/sc/docs/apps/msp/intrface/usb/emitest.pdf

http://www.usb.org/developers/docs/hs_usb_pdg_r1_0.pdf

http://www.usb.org/developers/docs/devclass_docs/CabConn20.pdf


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## gregorio

Puma Cat said:


> [1] Thats what better cables do, preserve signal integrity and minimize the impact of noise.
> [2] When I got into computer audio, I also didn't think a USB cable could make a difference, the old 'bits is bits' thang, but..._they do_. Wrong again.
> [3] I'm a scientist, I just go by what the data tells me, and controlled experiments tell me these cable make a difference. Just as better power supplies do.



1. We're not talking about an analogue signal, we're talking about digital data and the quality of that digital data signal is irrelevant. It makes zero difference how high the quality is of a transmitted zero or a one, as long as it's good enough that a zero can be differentiated from a one, anything beyond that cannot and does not make a difference. That's the whole point of digital audio and why it was invented. The issue Currawong and I have discussed, is that some DACs do not correctly isolate the power (which is also supplied in the USB protocol) from it's analogue side and noise is introduced, we're not talking about the actual digital data signal itself, which is effectively immune from noise.

2. A USB cable can make a difference! How it's marketed, what we believe about it's performance, what it looks like, how much it costs, can all make a difference to how we perceive it's performance.

3. As a scientist I would expect you to know the difference between the perception of differences and actual performance differences. I would like to see the data of the "controlled experiments" you mention, all the controlled experiments I've seen provide exactly the opposite data!



Whitigir said:


> [1] It is futile to try and convince the folks that cables do make differences.
> [2] It is more conveniences to find the negativities about these cables and just buy a cheaper and more affordable one and thinking that it makes 0 differences.  Really is futile to try and convince them.
> [3] Not to mentions that many people "thought" that they are technically advanced and "believe" that they know many many things about these cables with just "googling skills."



1. In my experience, it's the other way around. It's futile to try and convince some audiophile folks that cables don't make a difference, because they're incapable of believing any actual facts which may require the acceptance of the fact human perception is flawed and easily manipulated. This is a strange logical position to take, as pretty much all commercial audio content absolutely relies on manipulating hearing perception!

2. It's got nothing to do with convenience of cheaper/more affordable. It's pretty much guaranteed that I've spent far more time and probably money on audio equipment than you and just about every other audiophile. If USB cables really did make a difference, a few hundred bucks is peanuts, however as they don't make any difference I'd rather spend that few hundred buck on something which does make a difference.

3. "Googling skills" is not the issue, the issue is understanding what google turns up, whether it's marketing BS or actual fact and there's a great deal more of the former than the latter because of the financial incentive.



Currawong said:


> The manufacturers I've spoken to, two of whom have posted here about it, thought that their USB implementations were good enough until they either did experiments themselves (with electronics, not cables) and/or had feedback from customers that they could be better.



They might have thought their USB implementations were good enough but obviously they made a mistake. Actually, they made two mistakes: 1. Their engineering design was flawed AND 2. Their quality control/testing was flawed. They should have done those experiments as part of their testing and identified and fixed that engineering flaw BEFORE the product was ever released!

G


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## theorist

Just discovered this thread. Sorry I missed the discussion three weeks ago. I'm on the side of the camp that all cables can make a big difference, especially USB cables, since they are the start of the signal chain (not including power), and with the lowest 'amplitude', if you will excuse this metaphor here.

I have been into audio for about 40 years. I use to design, make and tweak my own analogue gear when I was younger. I'm a university professor and my area of research concerns epistemology and the philosophy of science. I  can happily discuss how we humans tend to think in simple black and white metaphorical assumptions when we create models of how the world works.  This particularly applies to the 'offs' and 'ons' within the time domain of a digital signal, not to mention all the parasitical other types of noisy signals travelling around  through and between all the bits and pieces in that USB cable including the 5v dc power line contained with it.  

I have a rather expensive USB cable, listed below as one of the most expensive cables in my cabling loom. I also have a DAC which you can set the Femto Master Clock Speed for jitter control. Normally I have it set to EXACT which gives a very good jitter spec of 82 femtoseconds. You can set it to FINE or even COURSE which allows the DAC to have a very wide bandwidth so the DAC can lock on to pretty jittery sources. Anyhow, when I started to burn-in my new USB Cable (yes it requires burn-in), it was fine for the first 24 hours, then for about 48 hours it started to create really bad distortion when playing very aggressive music, like punk guitar (eg the Savage's first album), but was fine with less edgy stuff, like acoustic guitar. It was jitter being created in the cable. Turning the DAC clock to COURSE immediately passed a listenable signal, the next day only FINE was necessary and the following day with the cable starting to better burn-in, it could handle the signal back on EXACT without any distortion. It now sounds, of course, wonderful. So USB cables do sound different, they can create temporary distortion to do with burn-in, and this is observable in a very audible and measurable manner.


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## chef8489

theorist said:


> Just discovered this thread. Sorry I missed the discussion three weeks ago. I'm on the side of the camp that all cables can make a big difference, especially USB cables, since they are the start of the signal chain (not including power), and with the lowest 'amplitude', if you will excuse this metaphor here.
> 
> I have been into audio for about 40 years. I use to design, make and tweak my own analogue gear when I was younger. I'm a university professor and my area of research concerns epistemology and the philosophy of science. I  can happily discuss how we humans tend to think in simple black and white metaphorical assumptions when we create models of how the world works.  This particularly applies to the 'offs' and 'ons' within the time domain of a digital signal, not to mention all the parasitical other types of noisy signals travelling around  through and between all the bits and pieces in that USB cable including the 5v dc power line contained with it.
> 
> I have a rather expensive USB cable, listed below as one of the most expensive cables in my cabling loom. I also have a DAC which you can set the Femto Master Clock Speed for jitter control. Normally I have it set to EXACT which gives a very good jitter spec of 82 femtoseconds. You can set it to FINE or even COURSE which allows the DAC to have a very wide bandwidth so the DAC can lock on to pretty jittery sources. Anyhow, when I started to burn-in my new USB Cable (yes it requires burn-in), it was fine for the first 24 hours, then for about 48 hours it started to create really bad distortion when playing very aggressive music, like punk guitar (eg the Savage's first album), but was fine with less edgy stuff, like acoustic guitar. It was jitter being created in the cable. Turning the DAC clock to COURSE immediately passed a listenable signal, the next day only FINE was necessary and the following day with the cable starting to better burn-in, it could handle the signal back on EXACT without any distortion. It now sounds, of course, wonderful. So USB cables do sound different, they can create temporary distortion to do with burn-in, and this is observable in a very audible and measurable manner.


This is ridiculous. screwing around with the clock has nothing to do with the usb cable. usb cable does not need burn in. A usb cable has no sound. A digital signal does not pick up sound as it passes through the cable or wire as it travels.


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## theorist (Aug 29, 2017)

chef8489 said:


> This is ridiculous. screwing around with the clock has nothing to do with the usb cable. usb cable does not need burn in. A usb cable has no sound. A digital signal does not pick up sound as it passes through the cable or wire as it travels.



Of course a USB cable does pass a sound. It passes digital information from the cable's source which is always received imperfectly (due to enthropy and other factors this information can never be a perfect replication of its source, regardless of any error checking employed) and this received imperfect  information is then processed into sound by the DAC, the USB cable also passes lots of other spurious signals, generically called noise, which can further distort the direct processing of this information and in other ways generate other forms of distortion which can also effect the generated sound in the circuitry of the DAC.


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## chef8489

Usb cables do not pass sound they pass a digital signal . Digital are not sounds. If your cable is loosing data it is faulty. You can get 100 percent perfect with cheap usb and coax abd cat 5 and even other fiber cables. If you are getting noise and jitter from your source you need to fix it as thete is a problem and it is not the usb cable. 

But there is no sense in arguing with you as you ate so blinded and convinced and no logic and actual fact and logic could sway you. Its been proven with scientific measurements and double blind tests time and time again. And you guys just get more and more rediclous.


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## theorist

You can never prove anything with scientific method. Rather you can only test for falsification in the prediction of your model/hypothesis -- Karl Popper a rather famous Philosopher of Science.

But hey, the world is made of wonderful people that all have different views and perspectives. That's why its fun to have discussions in Head-Fi about our rigs and our music as well as the theories and practicalities that make it all work!


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## chef8489

You are incorrect. That is the whole point of the scientific method and testing hypothesis and theories. Once proved they become law. Ie law of gravity. It was proven via scientific method. Can esiely be proven repedially and thus is law.


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## Puma Cat (Aug 30, 2017)

chef8489 said:


> You are incorrect. That is the whole point of the scientific method and testing hypothesis and theories. Once proved they become law. Ie law of gravity. It was proven via scientific method. Can esiely be proven repedially and thus is law.


No, you are incorrect and Theorist is correct. You can never absolutely prove anything. You can only gather data that either leads one to accept or reject the null hypothesis, or alternatively, gather enough data to have confidence in supporting the Alternate Hypothesis. The alpha for the hypothesis tests such as this is usually set to 0.05 to determine wihich p-value is significant for accepting or rejecting the null. As as scientist, I've had these debates endlessly over the years and I've never seen anyone, ever, present *any* statistically valid data that supports the null hypothesis that cables do not make a difference. If you state they don't, then provide the data that fails to reject the null with a p-value > 0.05. Your comment above just tells Theorist and me that you do not really understand the scientific method in actuality, in a way that you can meaningfully interpret a statistically valid data set.My guess is that you don't even know what alpha and beta are with respect to hypothesis testing.


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## Puma Cat

chef8489 said:


> Usb cables do not pass sound they pass a digital signal . Digital are not sounds. If your cable is loosing data it is faulty. You can get 100 percent perfect with cheap usb and coax abd cat 5 and even other fiber cables. If you are getting noise and jitter from your source you need to fix it as thete is a problem and it is not the usb cable.
> 
> But there is no sense in arguing with you as you ate so blinded and convinced and no logic and actual fact and logic could sway you.* Its been proven with scientific measurements and double blind tests time and time again. And you guys just get more and more rediclous.*



_Really?_ Then show us statistically valid *data* that fails to reject the null.


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## chef8489

There is no data that backs uo your statements except from pople trying to push high end cables. I understand the scientific method quite well and have degrees in microbiology to prove it. I have also been at the audio game for 20 years and have spent a lot of money on cables both digital and analogue over the years. Done double blind test with hundreds of peopke. Sent cables to many places to be tested, and many other people on here have tested as well. There is a reason these threads are restricted to sound science section. You get a quality built 20.00 6 foot usb cable and it will sound and perform the same as a 1000.00 6 foot usb cable.


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## Rockofeller

Scientist chiming in here...no, you cannot prove something is true in  the strict sense using the scientific method. But you can make decisions and determinations. For all those interested, this UC Berkeley site is a great resource, and even talks about the above-referenced (and out-of-favor) idea of Popper re: science only disproving things. http://undsci.berkeley.edu/teaching/misconceptions.php


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## gregorio (Aug 30, 2017)

theorist said:


> [1] I'm a university professor and my area of research concerns epistemology and the philosophy of science. I  can happily discuss how we humans tend to think in simple black and white metaphorical assumptions when we create models of how the world works.
> [2] It passes digital information from the cable's source which is always received imperfectly (due to enthropy and other factors this information can never be a perfect replication of its source, regardless of any error checking employed) and this received imperfect information is then processed into sound by the DAC,
> [3] So USB cables do sound different, they can create temporary distortion to do with burn-in, and this is observable in a very audible and measurable manner.



1. I'm going to have to call you out on that one! The theory of evolution or the big bang theory are examples of scientific models to explain observations of how the world works, HOWEVER, this is NOT the case with digital audio. Digital audio theory does NOT exist as a model to explain observations of how the world works, digital audio does NOT exist in nature, DACs do not grow on trees, have to be mined or orbit stars! Rather, digital audio theory was developed, then proven mathematically and several decades later the technology was developed to implement that proven theorem. If the theory of evolution were incorrect that wouldn't change the existence of millions of fossils and observations, just our explanation of them. On the other hand, if digital audio theory were incorrect, there would be no digital audio. It's inconceivable that a university professor (of science philosophy) would not know/understand these absolute basics of science and technology, hence why I'm calling you out!

2. No, the whole point of digital audio is that it is NOT analogue audio, digital data is not analogous to the electrical (analogue) signal and therefore imperfections in the digital data signal are NOT "then processed into sound". It does not make the slightest of differences how perfect, imperfect, noisy or clean a "1" or "0" is, that's the whole reason digital audio was invented in the first place and indeed the entire existence of all digital technology (digital information theory) is based on this principle. Again, how could a professor in science philosophy not understand even the fundamental basics of digital technology?

3. As you're a university professor you must obviously have reliable evidence/data to back up your claims? I myself (and countless others) have measured bit perfect transfer of digital audio data over cheap/stock USB cables and there are billions of people who can attest to bit perfect transfer of digital data via non-audiophile USB cables. Like tens of millions of others, I transfer masses of data every day over normal USB cables; videos, documents, audio files, etc., and if cheap/stock USB cables were not capable of transferring this data perfectly then either the USB protocol or the computing/digital world we live in could not and would not exist today! Digital data is by definition black and white, zeros or ones, there is nothing else and if there were, then by definition it couldn't be digital! Again, how can even a normal, rational person not understand this, let alone a university professor?

G


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## Arpiben

Let's also consider/remind that DACs manufacturers are using ready made USB decoders chips or even multipurpose microcontroller chips including USB functionalities.
I am supposing that those chips susceptibly to voltage noise & different parameters are not always properly taken into account.


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## Jazmanaut

Theorist: You are professor of philosophy. That does not really mean nothing recard your undestanding of digital technology, or even audio per se.

^^Gregorio: I just love you.


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## gregorio

Arpiben said:


> I am supposing that those chips susceptibly to voltage noise & different parameters are not always properly taken into account.



Agreed, I've heard a quite expensive DAC which did not "properly take that into account". On the other hand, I've used sub $100 pro audio USB ADC/DAC which did. This begs the question; how can an audiophile USB DAC with less than half the components of a pro audio USB ADC/DAC but several times the price fail to take into account the USB specification? This issue is about a DAC manufacturer's competence in handling the USB power supply though, rather than of digital audio data transfer integrity. Sure, one could buy an essentially faulty audiophile USB DAC and then an expensive cable to isolate the USB supplied power. Personally, I'd rather buy a competently designed USB DAC which can actually live up to it's name by properly dealing with the USB specification in the first place ... but that's just me! 
G


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## Ynot1

I think much of the discussions have been surrounding the theoretical limits of usb cable, and I am not able to challenge the reasoning either way.
I just want to know, does it really save money for manufacturing usb cables without the data line? For all those times I've been burned using charge cables when I needed data line, I wish I had a nickel for it each time.


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## Rockofeller

gregorio said:


> 1. I'm going to have to call you out on that one! The theory of evolution or the big bang theory are examples of scientific models to explain observations of how the world works, HOWEVER, this is NOT the case with digital audio. Digital audio theory does NOT exist as a model to explain observations of how the world works, digital audio does NOT exist in nature, DACs do not grow on trees, have to be mined or orbit stars! Rather, digital audio theory was developed, then proven mathematically and several decades later the technology was developed to implement that proven theorem. If the theory of evolution were incorrect that wouldn't change the existence of millions of fossils and observations, just our explanation of them. On the other hand, if digital audio theory were incorrect, there would be no digital audio. It's inconceivable that a university professor (of science philosophy) would not know/understand these absolute basics of science and technology, hence why I'm calling you out!
> 
> 
> G


Actually, I have to call you out on this one. This is completely wrong, although stems from a rather common misunderstanding, so don't feel too bad. Models and theories are just that - conceptual. It doesn't matter if you're talking about a model of real world phenomena or a theoretical system to be implemented out in the world. In the end, these models, which we can describe with words, math etc are simple-in fact, that's why they're helpful to us. Because the world is infinitely complex. So if you take a model about digital audio transfer and implement it in the real world, at best you have something PREDICTIVE. Not only does your argument that "since we invented it, then implemented it" not hold for this case, it will never hold, ever, in any endeavor.


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## theorist (Aug 30, 2017)

Well stated!

Take digital cables, even though I know better I still picture a digital cable: USB, Ethernet, S/PDIF, Toslink, etc like a hose pipe (NZ term where I live) with little perfectly sized 'bits' of 'on(s)' going down it between perfectly sized 'spaces' of 'off'(s). The actual reality -- the 'thing-in-itself' -- is impossible to put into actual mental representation, hence we use simple metaphors like that  of the garden hose (US term, I think). Indeed, no one actually knowns how the electro-magnetic spectrum actually works or looks like (if one could sense it) in reality, hence we build theories and models about it, and if they work most of the time, we then use these theories and models in our engineering, including that of digital and analogue audio. But the thing about science is that our knowledge in never absolute, the paradigm always gets overturned -- think of the 1980s claim of CDs as perfect sound, because in the measurements used at the time it was pretty near perfect, as no one had yet discovered jitter (among other things), what jitter does to musical sound and how to measure it! Similarly, our current models will one day be overturned. Top audio designers are at the cutting edge of this and one can argue that this is what we are paying for, at least in part, in the cost of reputable high end cables, unfortunately, there are always some cowboys selling expensive snake-oil, but that is another story! There was a good editorial/comment in 'The Absolute Sound' a few months ago of the effects of latency (how things take time to start moving and stopping in response to sound waves or other physical inputs of energy, a skew rate in electronic terms, or the time delay in your internet connection before triggering a response) of microphones in recording music and how we can therefore never have perfect sound -- its a good read, if you have not seen it.

If I may make a reply to some other posts here responding to my earlier ones. Karl Popper's argument was not that science could only disprove things, rather that the scientific method is predicated on testing if proposed theories actually replicate what happens in the real world and you could not call something scientific unless it could pass the test of falsification, ie the model being proposed can be be tested as valid through observation of it working in the real world (and it would remain considered 'valid'  until it was shown to not work). He famously argued in the 1950s that  the then claims for Marxian science and Freudian science were not actual science, as their theories could not be scientifically tested through repeatable experimentation and observation -- he called this the test of falsification -- by comparing them to Einstein's relativity where Einstein stated that gravity can bend light and he produced a formula in 1915 predicting how much it would bend. This was shown to be an accurate prediction the next time a solar eclipse occurred about three years later when someone measured the bending of light of a star behind the sun, confirming Einstein's prediction and hence the validity of the theory of relativity itself.

I just have a knowledgeable lay-knowledge of digital audio, but a pretty good knowledge of analogue audio, as, back in the days of the Audio Amateur I used to make my own designs of audio circuits for pre-amps, amps and the like, prototype, test/measure/listen/modify/etc, layout circuit boards, etch and build them, etc. Some worked pretty well, others less so! I did a bit of digital design but back in the 1970s that was before it was used for sound reproduction, just very simple computers with 8008s and the like.


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## Currawong

Seriously? If you put a digital signal into an oscilloscope you will see a square wave. That is something you can mentally conceptualise. The "bits" you talked about before DO arrive perfectly. If they don't, you get audible pops and clicks. I think what you mean about the limitations of science is really the limitations of your own understanding. The means by which electronic circuits work can perfectly explain how electrical noise from one connected device can end up in another part of the circuit.



gregorio said:


> They might have thought their USB implementations were good enough but obviously they made a mistake. Actually, they made two mistakes: 1. Their engineering design was flawed AND 2. Their quality control/testing was flawed. They should have done those experiments as part of their testing and identified and fixed that engineering flaw BEFORE the product was ever released!



Please explain, in detail, exactly what experiments and tests they should have done.


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## theorist (Aug 31, 2017)

Do digital bits arrive perfectly? Then why do we have jitter (time smear) in everything digital. That's why some sophisticated USB inputs re-clock the arriving signal before passing it on in the circuit for reprocessing it to sound.

Further, if you look at a digital signal in an oscilloscope of greater resolution and one capable of capturing a narrower (ie faster) slice of time it will be far from square (the inherent slew rate alone must cause this, but other factors, such as capacitance interaction with the cable's insulation (a dielectric can never be a perfect insulator, this can only occur in a pure vacuum) and every physical change of material (circuit to plug to socket to wire to socket to plug to circuit -- even without any bad soldiers) the digital signal goes through also further creates capacitance ringing even with digital bits [like the ripples of water from a dropped stone on a pond]). The image you see is not that of the 'bit', it is simply something generated by the oscilloscope to a set of rules wired into the circuit as it reacts to the  received signal and the rules in standard oscilloscopes are normally set to remove any fuzziness of the image made by very low magnitude error (often the noise of oscilloscope itself, but also some of the initial signal noise).  Basically what you see is just another kind of metaphor, given as a 'standard' oscilloscope image, but it is not the 'bit' as a 'thing-in-itself'.


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## chef8489

theorist said:


> Do digital bits arrive perfectly? Then why do we have jitter (time smear) in everything digital. That's why some sophisticated USB inputs re-clock the arriving signal before passing it on in the circuit for reprocessing it to sound.
> 
> Further, if you look at a digital signal in an oscilloscope of greater resolution and one capable of capturing a narrower (ie faster) slice of time it will be far from square (the inherent skew rate alone must cause this, but other factors, such as capacitance interaction with the cable's insulation (a dielectric can never be a perfect insulator, this can only occur in a pure vacuum) and every physical change of material (circuit to plug to socket to wire to socket to plug to circuit -- even without any bad soldiers) the digital signal goes through also further creates capacitance ringing even with digital bits [like the ripples of water from a dropped stone on a pond]). The image you see is not that of the 'bit', it is simply something generated by the oscilloscope to a set of rules wired into the circuit as it reacts to the  received signal and the rules in standard oscilloscopes are normally set to remove any fuzziness of the image made by very low magnitude error (often the noise of oscilloscope itself, but also some of the initial signal noise).  Basically what you see is just another kind of metaphor, given as a 'standard' oscilloscope image, but it is not the 'bit' as a 'thing-in-itself'.


You are trying to apply analogue rules to digital signals and you can not do that. A digital signal either arrives or it does not. The dac see a 1 or a zero. and then converts them in to a physical signal.

The USB protocol (unlike SPDIF) does not have a single problem with jitter. In Asynchronous mode, the audio device does the clocking. It tells the PC to regulate its speed. As the clock is running on the audio device this solution can be implemented in such a way that the the DAC receives a signal with a very low jitter.

What you do have to worry about is using a dac that takes power over usb versus through a separate power brick. Then you might get electrical interference if your source is not good.


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## theorist

chef8489 said:


> You are trying to apply analogue rules to digital signals and you can not do that. A digital signal either arrives or it does not. The dac see a 1 or a zero. and then converts them in to a physical signal.
> 
> The USB protocol (unlike SPDIF) does not have a single problem with jitter. In Asynchronous mode, the audio device does the clocking. It tells the PC to regulate its speed. As the clock is running on the audio device this solution can be implemented in such a way that the the DAC receives a signal with a very low jitter.
> 
> What you do have to worry about is using a dac that takes power over usb versus through a separate power brick. Then you might get electrical interference if your source is not good.



A good discussion on jitter is at http://www.enjoythemusic.com/magazine/manufacture/0509/ Its a bit old as the reference to 192/24 makes clear, but still nice and comprehensive.


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## chef8489

That data is out of date and inaccurate.


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## theorist

chef8489 said:


> That data is out of date and inaccurate.



As the web page starts: in regards to jitter  "there are believers and unbelievers", and we are all entitled to our opinions. Ultimately, I believe in what my ears tell me.


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## Arpiben

@theorist 
For a better understanding of Jitter and where it applies, I will suggest you to read Julian Dunn's paper.
When dealing with USB data entry the criteria is Max Tolerable Input Jitter.
Basically you apply jitter to data entry until having errors....
There is no issue at all with it since the USB chip inside DACs tolerates huge values of it.
That is the reason why some posters keep telling you there is no issue at all with USB cable jitter.
Rgds.


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## gregorio

Rockofeller said:


> Actually, I have to call you out on this one.  ... Not only does your argument that "since we invented it, then implemented it" not hold for this case, it will never hold, ever, in any endeavor.



Obviously, if you're going to call me out on this one you've also got to call out the hundreds of millions of people who've transferred countless petabytes of data via USB over the last 20 years, bit perfectly AND without having to rely on audiophile grade USB cables to achieve this feat!



theorist said:


> A good discussion on jitter is at http://www.enjoythemusic.com/magazine/manufacture/0509/ Its a bit old as the reference to 192/24 makes clear, but still nice and comprehensive.



Why would a self proclaimed university professor be quoting marketing material rather than actual scientific papers? And, not only are you quoting marketing information rather than actual reliable data/evidence but marketing information which completely contradicts your claims? You stated "_It was jitter being created in the cable_" but the article you describe as "nice and comprehensive" states "_Digital Cables don't actively add jitter to the signal_". 

I don't get it, you're not only proving that you were lying about being a university professor but also that your claims about USB cables were false? If you really are a university professor then you can easily substantiate your claim that "_So USB cables do sound different, they can create temporary distortion to do with burn-in, and this is observable in a very audible and measurable manner._". 



Currawong said:


> Please explain, in detail, exactly what experiments and tests they should have done.



No idea, I was quoting YOU! 
"_Remember that the Wyrd, and subsequently the Eitr, come from highly experienced and competent designers who were wyrd-ly surprised by their *experiments* and their results, having previously thought that the USB they had designed was good enough._"
"_The manufacturers I've spoken to, two of whom have posted here about it, thought that their USB implementations were good enough until they either did *experiments* themselves (with electronics, not cables) and/or had feedback from customers that they could be better._"

G


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## theorist (Aug 31, 2017)

gregorio said:


> Why would a self proclaimed university professor be quoting marketing material rather than actual scientific papers? And, not only are you quoting marketing information rather than actual reliable data/evidence but marketing information which completely contradicts your claims? You stated "_It was jitter being created in the cable_" but the article you describe as "nice and comprehensive" states "_Digital Cables don't actively add jitter to the signal_".
> 
> I don't get it, you're not only proving that you were lying about being a university professor but also that your claims about USB cables were false? If you really are a university professor then you can easily substantiate your claim that "_So USB cables do sound different, they can create temporary distortion to do with burn-in, and this is observable in a very audible and measurable manner._".
> 
> ...



First off, as any prof knows, undergrad students, even in their own field of study, have difficulty reading academic journal articles -- they are difficult to understand without a lot of prior specialized knowledge, which is largely developed in graduate school doing their masters and then PhD -- that's why you have u/g textbooks, as they are easier to read and always explains the basics as was the case of the article I posted a link to (journal articles assume the reader knows all the basics and the specialised terminology used within it).

Also journal articles are peered reviewed by academic peers to ensure good scholarship. One of the sins of bad scholarship that peer reviewers are there to expose is the quoting of other literature incorrectly, or out of context. The full quote you partially stated is:  "_Cables don't actively add jitter to the signal, however they can slow the signal transitions or "edges". When the edges are slowed, the receiver or buffer at the cable destination is less likely to detect the transition at the correct time with certainty, which results in jitter._" [technically this should be an indented quote as its more than one sentence -- but, hey, this is a discussion forum!]

In the case of part of the burn-in period of the USB cable I referred to, it was generating extremely high distortion with certain kinds of music, which I assume was jitter related (what else could it be since it was clock bandwidth, ie time, sensitive), replacing the USB cable with another in the system removed this jitter, returning it to the system returned the jitter. Putting the Auralic Vega DAC clock bandwidth setting to 'course' allowed the DAC to process this jittery data and play without audible distortion, on 'fine' it could not handle it without producing extremely un-listenable distortion -- I note there was no drop-outs in the music, it played continuously, but with extreme distortion, especially when the music got more complex with lots of transients. Perhaps the reason for this was the one stated in the quote about "edges" (aka rise time/slew rate) due to some specific attribute of burn-in, perhaps it was some other factor. I do not know, or particularly care as it went away with another 50 hours of burn-in. But it was clearly audible and, in its sensitivity to the 'bandwidth' setting, it was clearly measurable.

Finally, I am not a prof in the field of audio engineering or IT, nor have I claimed to be, my research is in how scientific and other knowledge is applied and used (often incorrectly through misunderstanding/overly simplifying it, etc, -- indeed, the world is actually very complex) within government policy. I largely draw on European philosophy and post-structural theory in doing so. I won't be more specific because in my very small country of New Zealand I can be too easily identified and I don't feel like having my house turned over for my gear!


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## Currawong

theorist said:


> [...] I assume was jitter related [...]
> 
> [M]y research is in how scientific and other knowledge is applied and used (often incorrectly through misunderstanding/overly simplifying it, etc,



My father wrote a couple of books on pretty much the very same thing, though directed at ordinary people, which you might appreciate. That being said, as rude as this is going to sound, I think your assumption is an example of your research.


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## gregorio

theorist said:


> [1] First off, as any prof knows, undergrad students, even in their own field of study, have difficulty reading academic journal articles
> [2] The full quote you partially stated is:  "_Cables don't actively add jitter to the signal, however they can slow the signal transitions or "edges". When the edges are slowed, the receiver or buffer at the cable destination is less likely to detect the transition at the correct time with certainty, which results in jitter._"
> [3] In the case of part of the burn-in period of the USB cable I referred to, it was generating extremely high distortion with certain kinds of music, [4] which I assume was jitter related .. [5] Putting the Auralic Vega DAC clock bandwidth setting to 'course' allowed the DAC to process this jittery data and play without audible distortion, on 'fine' it could not handle it without producing extremely un-listenable distortion -- [6] I note there was no drop-outs in the music, it played continuously, but with extreme distortion, especially when the music got more complex with lots of transients. [7] Perhaps the reason for this was the one stated in the quote about "edges" (aka rise time/slew rate) due to some specific attribute of burn-in, perhaps it was some other factor. [8] I do not know, or particularly care as it went away with another 50 hours of burn-in. [9] But it was clearly audible and, in its sensitivity to the 'bandwidth' setting, it was clearly measurable.
> [10] Finally, I am not a prof in the field of audio engineering or IT, nor have I claimed to be, ...



1. But according to you, you are not an undergrad, you're a prof and should have less difficulty reading a journal article than an undergrad! If uni professors relied solely on consumer review magazines for their knowledge and research rather than on peer reviewed papers, there would be no science and we'd still be in the dark ages ... that's why peer reviewed scientific papers exist, as any undergrad should know, let alone a real uni prof!
2. No! The "slowed edges" result in what's called an "eye pattern". The transition times/shape of this eye pattern is part of the USB specifications. So, either a cable can transfer the signal within these USB specifications, in which case it is a USB cable, or it cannot, in which case it is not a USB cable! So even a 99c no brand USB cable can transfer a USB signal perfectly. Likewise with a DAC, either it can handle a USB specified (eye pattern) signal or it cannot, in which case it's not a USB DAC. Therefore, if "the receiver or buffer at the cable destination" is unable to accurately detect the transition of a USB specification signal and deal with it appropriately, then it is NOT a USB device (or it's a faulty one).
3. NO! USB cables do NOT carry music, only on/off voltages representing zeros and ones. A USB cable does not know it is transferring audio, let alone know that audio is music, less still music of certain genre. It's just digital data, zeros and ones, which could represent anything from a word document to a feature film or the schematics for a jet liner. What if you send a selfie of your private parts down an un-burnt-in USB cable, does it generate "extremely high distortion" of that too or does it only wait for the zeros and ones which represent "certain kinds of music"?
4. Even an undergrad should know that you can't claim anything based only on assumption. In fact, that would be the very antithesis of science, as you would know only too well if you really were a uni prof dealing with scientific knowledge!
5. If your Auralic Vega DAC cannot adequately handle a USB specification signal without extreme distortion, then it is not a USB DAC (or it's a seriously faulty USB DAC). And, what is it you think your burnt-in audiophile cable is doing to the zeros and ones which a standard USB specification cable is not, to cause this "clearly audible" difference?
6. A USB cable does not transfer any transients, ONLY zeros and ones and, it's does not know what those zeros and ones represent and change it's behaviour accordingly! It's just a few strands of metal wire with no intelligence, no computational power and no magic!
7. Again, either the "rise time/slew rate" of the signal transferred by the cable is within the USB specifications or it is not a bona fide USB cable!
8. Even a moderately rational high school student should not be making claims  if they "do not know", let alone an undergrad and heaven forbid an actual uni prof!!!
9. Again, pure speculation/assumption, something a real uni prof would NEVER base a claim upon! And, even an undergrad should know that something clearly audible/perceivable does not necessarily mean clearly measurable. It is trivial to perceive significant differences where in fact there are none and again, this is part of a fundamental tenet of science, which apparently as a uni prof you don't know!?
10. What does being a prof in audio engineering have to do with anything (?), USB cables do not carry audio, just zeros/ones and you don't need to be an IT prof to know and understand this basic fact of digital data!

G


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## Clive101

Just had a quick read through the blog.

I am not a scientist nor have magic ears.

I do know what sounds good to me, I have tried and tested several makes and expensive and cheap USB leads and despite what people say on this thread they do make a difference.

I found noise being injected into my system via the network the better USB leads helped with this.

All in all if you enjoy  the cheap USB sound perhaps you have no noise or do not realise it is present.

I now go direct USB to DAC no network no noise.

If you'd want more detail just post


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## gregorio

Clive101 said:


> [1] All in all if you enjoy  the cheap USB sound perhaps you have no noise or do not realise it is present. [2] I now go direct USB to DAC no network no noise.



1. There is no cheap or expensive USB sound, there are no expensive or cheap sounding zeros or ones, just zeros and ones. If there were expensive and cheap sounding zeros and ones then by definition it would not be digital audio (or digital data of any kind) and likewise, it would not be USB. 
It really is quite shocking the number of people here who apparently do not know what digital means??? 

2. If your DAC really is producing spurious audible noise from a USB specification signal (transferred by a standard USB compliant cable) then your DAC is not USB compliant and is therefore not a USB DAC! You've either been unlucky and got a faulty USB DAC or you've been scammed by a company selling a DAC as USB compliant which isn't.

G


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## Clive101 (Sep 1, 2017)

Interesting reply @gregorio
I always thought that zeros and ones that you refer to was a wave-form sent down the cable to represent zeros and ones....?
I had noise entering my DAC ( Chord Dave ) not sure RF or electrical noise but some USB cables handled the noise better than others and hence sounded better.
For example the standard USB printer cable from a pc transmits zeros and ones sounded rubbish whereas a Chord Music USB sounded subline.
I also tested with a Tours power conditioner this also improved the zeros and ones.
I can only say if zeros and ones were the only thing being transmitted there would be no change but there was a monumental change in SQ using the different USB cables and power supply.
If you have no difference in your system you have no interference from RF or electrical noise or equipment which may not show the difference...?


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## Arpiben

Hi @Clive101,

Let's remind that the main role of a digital transport, in our case USB Audio, is to carry the data keeping its integrity from A to B. As soon as USB transmitter/Receiver and cable are compliant with specifications 0s and 1s will arrive at B unchanged. 
Using fancy cables to correct other deficiencies( DC power/ EMI/RFI / ground currents or loops/ DAC or DAP noises ) is IMHO not the most efficient cure.

When listening to my Chord Mojo while AC/DC charging it through USB if I happen to touch any metallic piece of my headphone/cable/Mojo I clearly hear a loud 50Hz humm. Am I wearing gloves, buying USB cables costing half of my DAC in order to lower it? Am I changing my body resistance to ground? No, since I learnt to live with my equipment weaknesses I simply unplug the power socket.....
Rgds


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## gregorio

Clive101 said:


> [1] I always thought that zeros and ones that you refer to was a wave-form sent down the cable to represent zeros and ones....?
> [2] For example the standard USB printer cable from a pc transmits zeros and ones sounded rubbish whereas a Chord Music USB sounded subline. ... I also tested with a Tours power conditioner this also improved the zeros and ones.
> [3] I can only say if zeros and ones were the only thing being transmitted there would be no change but there was a monumental change in SQ using the different USB cables and power supply.
> [4] If you have no difference in your system you have no interference from RF or electrical noise or equipment which may no show the difference...?



1. Not an audio waveform. It's just an on/off voltage which is transmitted along a USB cable as an "eye pattern", the properties of which are specified as part of the USB specification and which a cable has to comply with in order to be a certified USB cable.
2. Again, there can be no difference between a rubbish "1" and an expensive "1" or a rubbish "zero" and an expensive "zero". Digital data is a binary (1 or 0) system, your definition of digital data would need at least a quarternary system (rubbish 1, expensive 1, rubbish 0, expensive zero). Even if an audiophile USB cable could turn a rubbish "1" into an expensive "1" it cannot make any difference because as far as digital data is concerned a rubbish "1" and an expensive "1" are both exactly the same thing, just a "1"! This of course is the great advantage of digital audio over analogue audio and why it was developed in the first place!
3. Along with the actual data, the USB specification also allows for a power supply. There have been some cases of audiophile DACs which improperly handled that power and allowed it to create noise in their analogue stages. These DACs are obviously failing to correctly deal with the USB specification. This issue has nothing to do with the integrity of the digital data itself.

4. Yes, I've got very significant RF and equipment noise (both electrical and acoustic) from stacks of equipment. So much so that I need a dedicated machine room to house it all. As well as my 3 x 16 channel pro ADC/DACs, 3 workstations, amps and all the masses of other equipment piled into that room, I've got a cheap little pro audio stereo USB ADC/DAC connected with an Amazon Basics USB cable and no spurious noise! And, I most certainly do have the audio environment/equipment to show the noise if there were any.

G


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## Clive101 (Sep 1, 2017)

@gregorio and @Arpiben
Thanks for your very detailed replies but i can only trust my ears.
A cheap USB cable sounded rubbish the Chord Music I ended up with was the best followed by Sarum T and close or tie was the curious cable.
I did try cheaper USB cables but to my ears which I trust were a no go but would have been cheaper....!
If you found a Cheap USB cable ok then great.
Have you all tried different USB cables ...?
At many HiFi shows you can hear demos of different USB cables they do sound different on the same equipment


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## chef8489

Clive101 said:


> @gregorio and @Arpiben
> Thanks for your very detailed replies but i can only trust my ears.
> A cheap USB cable sounded rubbish the Chord Music I ended up with was the best followed by Sarum T and close or tie was the curious cable.
> I did try cheaper USB cables but to my ears which I trust were a no go but would have been cheaper....!
> ...


Guarentee you would not be able to tell the difference in a controlled double blind test setup by someone other than you.


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## gregorio

Clive101 said:


> @gregorio and @Arpiben
> [1] Thanks for your very detailed replies but i can only trust my ears.
> [2] A cheap USB cable sounded rubbish the Chord Music I ended up with was the best followed by Sarum T and close or tie was the curious cable. I did try cheaper USB cables but to my ears which I trust were a no go but would have been cheaper....!
> [3] If you found a Cheap USB cable ok then great. Have you all tried different USB cables ...?



1. Those of us who create audio content for a living absolutely rely on the fact that you cannot trust your ears. If you really could trust your ears then almost none of the commercial audio content you hear every day would make any sense at all and music would not exist for you.
2. Then either your perception of what you thought you heard was temporarily fooled, the USB cable was faulty, broken or not a USB cable or your DAC has a fairly serious flaw/fault.
3. Not only did it sound OK but it transferred bit perfect results and as far as digital data is concerned, a USB cable by definition cannot get any better than that! Having said that, I have heard an expensive audiophile cable USB and compared it with a cheap/standard one.

G


----------



## Clive101

chef8489 said:


> Guarentee you would not be able to tell the difference in a controlled double blind test setup by someone other than you.


Rubbish comment 
Not worthy  of a reply


----------



## chef8489

Clive101 said:


> Rubbish comment
> Not worthy  of a reply


It is not a rubbish comment. It has been proven time and time again in tests. Once you rule out the visual factor and you knowing which cable you are listening to. You can not tell the difference if done properly by a 3rd party not trying to sell cables.


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## Clive101

gregorio said:


> 1. Those of us who create audio content for a living absolutely rely on the fact that you cannot trust your ears. If you really could trust your ears then almost none of the commercial audio content you hear every day would make any sense at all and music would not exist for you.
> 2. Then either your perception of what you thought you heard was temporarily fooled, the USB cable was faulty, broken or not a USB cable or your DAC has a fairly serious flaw/fault.
> 3. Not only did it sound OK but it transferred bit perfect results and as far as digital data is concerned, a USB cable by definition cannot get any better than that! Having said that, I have heard an expensive audiophile cable USB and compared it with a cheap/standard one.
> 
> G


Rubbish reply


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## Clive101 (Sep 1, 2017)

chef8489 said:


> It is not a rubbish comment. It has been proven time and time again in tests. Once you rule out the visual factor and you knowing which cable you are listening to. You can not tell the difference if done properly by a 3rd party not trying to sell cables.


So you know what I hear as others who also confirmed Night and day differance no need for the double blind test waste of time.
Stay with your USB and move on.


----------



## gregorio

Clive101 said:


> Rubbish reply



Why, because you are incapable of understanding it or because you're too invested in your faulty DAC and marketing driven wasted purchase of an expensive cable to even consider the actual facts?

G


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## Clive101

gregorio said:


> Why, because you are incapable of understanding it or because you're too invested in your faulty DAC and marketing driven wasted purchase of an expensive cable to even consider the actual facts?
> 
> G


I understand you are incapable of understanding what I hear as others do on my system as you have not had the privilege. If your DAC sounds good to you with your cheap USB so be it.


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## gregorio (Sep 1, 2017)

Clive101 said:


> I understand you are incapable of understanding what I hear as others do on my system as you have not had the privilege. If your DAC sounds good to you with your cheap USB so be it.



If your faulty DAC (or other system component/s) and expensive cable sound good to you and your happy about it, then that's a little strange but entirely up to you. Listening to a faulty system is hardly a "privilege" though, quite the opposite! A privilege as far as I'm concerned is a non faulty DAC/system, bit perfect cables and controlled, highly accurate listening environments.

I still don't know which of those two options is your problem for sure but your response indicates the latter or maybe both!

G

EDIT: And by the way, in case it isn't already clear, my "cheap USB cable" transfers data bit perfectly and is therefore at least as good or better than your audiophile USB cable. Your USB cable CANNOT be better than mine because there is nothing better than bit perfect transfer!!!


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## Clive101 (Sep 1, 2017)

gregorio said:


> If your faulty DAC (or other system component/s) and expensive cable sound good to you and your happy about it, then that's a little strange but entirely up to you. Listening to a faulty system is hardly a "privilege" though, quite the opposite! A privilege as far as I'm concerned is a non faulty DAC/system, bit perfect cables and controlled, highly accurate listening environments.
> 
> I still don't know which of those two options is your problem for sure but your response indicates the latter or maybe both!
> 
> G


 So my system is faulty and you deduce that because I use a high quality USB lead ( which sounds better ) rather than a Cheap USB  cable.
Well your intitled to your opinion and wish you best of luck with your DAC and cheap USB cable.


----------



## gregorio

Clive101 said:


> I use a high quality USB lead ( which sounds better ) rather than a Cheap USB  cable.



You just don't seem to be getting it, you DO NOT use a USB lead which is higher quality than mine. My cable provides bit perfect results and as there is no quality which is higher than perfect, therefore either you've paid a lot more for a cable which provides the same quality as mine or, if your cable produces something other than the bit perfect results of my cable, then you've paid a lot more for a cable which actually provides lower quality than mine. If your cable really is producing something other than the bit perfect result of my cable and it really does sound better to you, that must mean that you just prefer the sound of a poor quality/inaccurate USB transfer?! This isn't some complex theoretical problem, just the basic fact of what is digital data and simple logic, your response further confirms that one or both of the options I presented must be correct.

G


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## Clive101

gregorio said:


> You just don't seem to be getting it, you DO NOT use a USB lead which is higher quality than mine. My cable provides bit perfect results and as there is no quality which is higher than perfect, therefore either you've paid a lot more for a cable which provides the same quality as mine or, if your cable produces something other than the bit perfect results of my cable, then you've paid a lot more for a cable which actually provides lower quality than mine. If your cable really is producing something other than the bit perfect result of my cable and it really does sound better to you, that must mean that you just prefer the sound of a poor quality/inaccurate USB transfer?! This isn't some complex theoretical problem, just the basic fact of what is digital data and simple logic, your response further confirms that one or both of the options I presented must be correct.
> 
> G


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## Clive101

I have never compared your usb cable to mine. I have no intention.
It would seem you have an opinion and so do I , they differ.
I think you need to understand we have different views.
You with one cable me with another.
I have no interest in any further debate.
My experience is different to yours that's all.
Perhaps you should reflect on earlier posts on this thread other people have a similar view to mine and you did not agree can we all have faulty equipment!
Your system works for you with your USB lead fine I have no issues with that.


----------



## chef8489

gregorio said:


> You just don't seem to be getting it, you DO NOT use a USB lead which is higher quality than mine. My cable provides bit perfect results and as there is no quality which is higher than perfect, therefore either you've paid a lot more for a cable which provides the same quality as mine or, if your cable produces something other than the bit perfect results of my cable, then you've paid a lot more for a cable which actually provides lower quality than mine. If your cable really is producing something other than the bit perfect result of my cable and it really does sound better to you, that must mean that you just prefer the sound of a poor quality/inaccurate USB transfer?! This isn't some complex theoretical problem, just the basic fact of what is digital data and simple logic, your response further confirms that one or both of the options I presented must be correct.
> 
> G


The thing is, he paid more for his cable, so he is deluding himself into thinking and fully beliving that they sound different. That is why he needs a double blind test setup by someone else not trying to sell cables. But he will never go for it as he has too much to loose. Remember we dont know what he can hear even though we have been at this for several decades and have been up and down the price scale with gear. Tested and re tested the gear and blind tested it.


----------



## gregorio

Clive101 said:


> [1] I have never compared your usb cable to mine. I have no intention.
> [2] It would seem you have an opinion and so do I , they differ. [2a] I think you need to understand we have different views.
> [3] Perhaps you should reflect on earlier posts on this thread other people have a similar view to mine and you did not agree can we all have faulty equipment!
> [4] I have no interest in any further debate.



1. Others can read your quote/posts and decide for themselves what your intention was.
2. No, I have data which shows my cheap USB cable provides the highest quality possible, bit perfect transfer. You on the other hand seem to have an opinion which flies in the face of the facts and simple logic, that your expensive cable provides higher quality than perfect and it therefore somehow defies the basic principles of digital data.
2a. Of course, you can ignore the facts and have whatever view you wish. You could for example have the view that 1 + 1 = 3.  
3. And perhaps you should reflect on the hundreds of millions of people who've enjoyed countless petabytes of USB data transfer bit perfectly for 20 years using standard/cheap USB cables but of course, you won't do that, actual facts and logic apparently have no impact on you, the opinions of a tiny group of audiophile extremists, the marketing BS designed to relieve them of their money and your own investment in it are the only things which appear to influence you, which brings us right back to the second option I mentioned!
4. Of course you don't and I fully appreciate why.

G


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## theorist (Sep 1, 2017)

An interesting overnight exchange! While I side with Clive101 I have learnt some technical details about USB standards from Arpiben and gregorio I was not aware of, so thank you for that. Further, I also agree with the basis of what I think was chef8489's argument about how we interpret our senses mentally, which was very much consistent with Kant's version of German Idealism, which I rather generally agree with. That is that everything is open to how we interpret what our senses present to our mind about the world, and we all do that mental processing a bit differently. But, where I differ with my critics is that you all appear to think that there can be be such a thing as perfection, eg a perfect transfer of information. This I cannot agree with.

Everything in the universe is subject to entropy, information loss, a digital signal is no exception, and off course there are IT protocols to deal with this, which I have no great knowledge of, but I know this is why my Word document is always almost always printed out 'perfectly' and my music played back off my server without drop outs. But ultimately there is also a matter of what my ears tell my mind. At least, my mind does interpret what I hear as a very significant difference between better and worse USB cables, not that dissimilar to the variations of quality I can also hear between different types of any other kind of audio component in the system.

For USB cables, perhaps this is down to the parasitic noise that these cables also  transfer with the 'perfect' bits, or not (or an artifact of the error correction being employed somewhere in the signal path to ensure these bits are 'perfect'). But I do know that there are differences between the sound I get when I have different quality USB cables in my system and that this difference in quality does not always correlate with the cost of the USB cable. Further, without pretty good gear within my system, I suspect that these differences would undoubtedly be much less noticeable as, no doubt, they would be masked by the lower resolving gear.

I look forward to more comments on this discussion and I value them from all perspectives, because we all have a strong interest in our music and hobby in common, otherwise we would not get passionate about it!


----------



## gregorio

theorist said:


> [1] But, where I differ with my critics is that you all appear to think that there can be be such a thing as perfection, eg a perfect transfer of information.
> [2] This I cannot agree with. ... Everything in the universe is subject to entropy, information loss, a digital signal is no exception, ...
> [3] But ultimately there is also a matter of what my ears tell my mind.



1. Then you have to discount/ignore both your own experience of printing your word documents and the hundreds of millions/billions of people and countless exabytes of data which has been transferred perfectly. And, not just music and word documents but critical data like schematics for buildings, vehicles, weapons and military data, medical technology/data, civil infrastructure, etc. We live in the digital age, how would that even be possible if the perfect transfer of digital data were not just a theoretical possibility but a trusted and completely expected reality? Indeed, it's hard to think of any fact which has been practically demonstrated more than the fact of perfect transfer of digital data! How can you logically rationalise this most demonstrated of facts with your assertion that the perfect transfer of digital data is impossible?

2. I only see two possible avenues of response to the previous question; Either your assertion is false and you have to question your knowledge/information upon which you've based that assertion or you have to respond illogically/irrationally. In part you've already unwittingly answered this question, with the statement I've quoted which indicates a serious hole in your knowledge, it indicates that your knowledge/research ends in the 1870's with the development of the second law of thermodynamics (Entropy). Your situation is analogous to someone whose knowledge/research ends with Newton's law of gravity in 1687 and therefore ignores the C20th work of Einstein which revolutionized our understanding of gravity. The C20th genius apparently missing from your knowledge/research is Claude Shannon, whose seminal paper in 1948 (A Mathematical Theory of Communication) mathematically proved that entropy can be manipulated to preclude information loss! It provides a mathematical proof of a communication system with a limit below which information will definitely be lost and above which it can be perfectly preserved. Shannon's paper is describing the digital system, although the term "digital" does not appear in his paper and wouldn't be coined for some years. Shannon has been called the father of the digital age because without this paper and it's proof of a method to preclude information loss, there would be no mass digital technology and no digital age! Your statement that "there are IT protocols to deal" with information loss is therefore not entirely correct, the protocol to deal with information loss is the digital system itself!!

3. No, because ultimately you have almost no idea what your ears are telling your mind! Information from the ears (to the mind/brain) is prioritized, most of it discarded and what's left is combined with other information (sensory and stored in memory) to produce an image of the sound which has essentially been created by your brain. This interpreted/manufactured sound is the ONLY thing of which you are aware. There is an entire field of science which specifically researches the difference between what enters our ears and how our ears and brain ultimately modifies and interprets this information, it's hard to believe that a uni prof specializing in the philosophy of scientific knowledge could apparently be ignorant of the existence of the field of science primarily concerned with the claims he is making?! That the brain is making a highly flawed representations/interpretations of what the ears are actually "hearing" is completely indisputable and is what allows us to manipulate what people hear ... or rather, what they think they hearing! Furthermore, this is hardly some new or contentious discovery, in fact the exact opposite, it's both ancient and ubiquitous and the vast majority of the commercial audio content you hear absolutely depends on it!! For example, there's a music genre called counterpoint which relies on what's called "implied harmony", harmony which isn't actually there in the music but which the brain predicts/invents itself, hence "implied" harmony. JS Bach was the master of counterpoint and he (and all other composers) was manipulating/fooling what listeners were certain their ears were telling them 300 years ago! I often hear the audiophile cry of "I trust what my ears tell me", which ultimately is nonsense because if they really could trust what their ears were telling them then pretty much all music (not just counterpoint) and indeed just about all commercial audio content in general, would sound like meaningless semi-random noise. When I hear audiophiles say of a recording that it sounded real, had a realistic sound stage, was like being there or lamenting that it doesn't sound real, I find that amusing as an audio content creator because it's complete nonsense. There was no "there", there was no real sound stage and most of the time there wasn't even a performance! If audiophiles were visiophiles, they would have to say that they believe what their eyes are telling them. In which case they must believe that Pandora is a real planet and that James Cameron must have taken a film crew there to shoot Avatar!

G


----------



## Cartma

This thread has gotten way outa hand. USB cables do make a difference, a very big difference.   Now back to the subject.. WHY?

Just ignore the ignorant.


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## chef8489

Cartma said:


> This thread has gotten way outa hand. USB cables do make a difference, a very big difference.   Now back to the subject.. WHY?
> 
> Just ignore the ignorant.


Sure they do.


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## gregorio

Cartma said:


> Now back to the subject.. WHY? ... Just ignore the ignorant.



Make up your mind, what is it you want? Do you want your question answered or do you want to be ignored?

G


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## theorist

gregorio said:


> Make up your mind, what is it you want? Do you want your question answered or do you want to be ignored?



But you have not answered WHY some USB cables improve the perceived musicality of a system over others USB cables, at least for many listeners.  

Its a question not dissimilar to comparing why a good analogue turntable based system sounds more musical for many listeners to that of an equal or even more expensive pure digital system, even if there are some digital signal stages in the production of the LP being listened to?

Sure, past experiences and biases may be a contributing factor for the listener, but it is only some peoples' opinion, including perhaps yours, say that this is the only reason. What I hear/perceive/intuit says otherwise. How do you explain how a twenty year old song that I have heard a thousand times over the years suddenly sounds unexpectedly clearer, more musical, just out-of-the-blue better, as though its the first time I have really really heard it, when the only change to the system since the last time I had listened to this song had been an upgrade to the USB cable six months before?

That's what I want to discuss. If you don't believe that that is at all possible, if this and similar experiences have not occurred for you, then don't partake in the discussion! But that would be a pity as you are obviously knowledgeable and likely have much to contribute.


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## bfreedma

Cartma said:


> This thread has gotten way outa hand. USB cables do make a difference, a very big difference.   Now back to the subject.. WHY?
> 
> Just ignore the ignorant.



And yet if I asked you to produce measurements showing this "very big difference", you wouldn't be able to.  Or asked for results of well controlled testing that validated this "very big difference", you wouldn't be able to produce that either.

How about even a reasonable theory based on what we know about the USB interface and cables indicating an audible difference is possible between two properly working cables.  Not the marketing claims from a cable makers website - something based on the known operating model for USB.  Again, something that would be audible....


----------



## chef8489

theorist said:


> But you have not answered WHY some USB cables improve the perceived musicality of a system over others USB cables, at least for many listeners.



It's called placebo. You can not trust your ears and that is what cable manufacturers count on. Problem is people like you who continually insist that you can and no need to do a double blind test are the ones they feed off. If you could do a double blind test and get every one correct then then it might have Merritt, but never happens. You might get people close to 50%. I was a big advocate for custom analogue cables and followed suite into digital cables instill I did the research and testing.


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## theorist

But a placebo effect cannot account for what I posted half an hour ago, which was:

How do you explain how a twenty year old song that I have heard a thousand times over the years suddenly sounds unexpectedly clearer, more musical, just out-of-the-blue better, as though its the first time I have really really heard it, when the only change to the system since the last time I had listened to this song had been an upgrade to the USB cable six months before?

There has to be other factors at work, just as when I swap USB cables in my system, there are changes to what I hear, and these changes do not just correlate to the cost/packaging/appearance of the cable.


----------



## chef8489

theorist said:


> But a placebo effect cannot account for what I posted half an hour ago, which was:
> 
> How do you explain how a twenty year old song that I have heard a thousand times over the years suddenly sounds unexpectedly clearer, more musical, just out-of-the-blue better, as though its the first time I have really really heard it, when the only change to the system since the last time I had listened to this song had been an upgrade to the USB cable six months before?
> 
> There has to be other factors at work, just as when I swap USB cables in my system, there are changes to what I hear, and these changes do not just correlate to the cost/packaging/appearance of the cable.


That happens all the time with the same gear. You hear things in songs you did not before, song sounds different,  clearer, amazing. Nothing new. We hear songs differently in different parts of the day, in different moods. That's again why you can not trust your ears. It's not the usb cable unless the usb cable is faulty. It's not like an analogue cable that you can change the sound by changing the cable material, dampening material, thickness of wire. There is no sound passing through the cable at all. No way for any additional info to be added to the 1 to change how it sounds. No way to add 0 or 1 unless you change the original file. It is just not possible to change the sound of a digital file inside an usb cable.


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## theorist

chef8489 said:


> It is just not possible to change the sound of a digital file inside an usb cable.



OK, lets take this as correct. Then what is changing the sound that I hear in my system when the only change made is the USB cable and I have had well over a dozen different ones in the current system, most of them loaners, including a  couple of beta cables that I have been asked to test from Tellurium given to me from one of my audio dealers? Is it the amount/type of parasitical noise coming over the cable along with the digital file? My music server has a choice of USB outputs and the one I use does not have the 5vdc output live, so its not traveling on that line.


----------



## chef8489

theorist said:


> OK, lets take this as correct. Then what is changing the sound that I hear in my system when the only change made is the USB cable and I have had well over a dozen different ones in the current system, most of them loaners, including a  couple of beta cables that I have been asked to test from Tellurium given to me from one of my audio dealers? Is it the amount/type of parasitical noise coming over the cable along with the digital file? My music server has a choice of USB outputs and the one I use does not have the 5vdc output live, so its not traveling on that line.


Why do you keep trying to make a usb cable like an analogue cable? There is no parasitic noise coming over a usb cable. There is no noise coming over a usb cable. The only thing that could be considered noise is when the power from the source is carried improperly from point a and used improperly on point be as it is not isolated bu a seperate power brick and creates power hum or distortion. This is not fixed with the usb cable and not the usb cables fault. You can fixing your source or by isolating your power on your dac. The only other option is that the usb cable is causing a short. or option 3 the data is not reaching in complete forms and you hear clipping and skipping.  You hear a difference with usb cables because you are convinced you can. 

You are so convinced and nothing we say will change your mind. I don't even think you would submit to a controlled scientific blind study if you were where one could be held by knowledgeable unbiased persons. So many people with far more knowledge and experience than you including people in the music industry has spoken up in this thread and you refuse to accept it or even consider it. You just went on how you are a professor even though it has nothing to do with this subject. Well guess what. I am also a professor, but has nothing to do with this subject so who the hell cares.


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## theorist

chef8489 said:


> You are so convinced and nothing we say will change your mind..



Ibid!


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## chef8489 (Sep 2, 2017)

theorist said:


> Ibid!


Except I was a believer in expensive cables till I was shown and proven with research. Problem is yuou are so far off and applying analogue audio properties where it is an impossibility as none of the equipment works the same during the digital path until it is converted to analogue.

I am done. Other people can chime in, but it is pointless as you can not comprehend the difference.


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## bfreedma

theorist said:


> OK, lets take this as correct. Then what is changing the sound that I hear in my system when the only change made is the USB cable and I have had well over a dozen different ones in the current system, most of them loaners, including a  couple of beta cables that I have been asked to test from Tellurium given to me from one of my audio dealers? Is it the amount/type of parasitical noise coming over the cable along with the digital file? My music server has a choice of USB outputs and the one I use does not have the 5vdc output live, so its not traveling on that line.




Placebo effect and expectation bias
They've been mentioned before, but you don't seem to want to give credence to them regardless of how well established they are as reasons people "hear" things when they change gear.


----------



## theorist

bfreedma said:


> Placebo effect and expectation bias
> They've been mentioned before, but you don't seem to want to give credence to them regardless of how well established they are as reasons people "hear" things when they change gear.



OK, lets take the two beta USB cables I was asked to test from a highly respected UK cable company. One made my system sound significantly worse that it was with my then current USB cable and the other one a bit better. I was not buying these cables, they were not even available for sale. They both looked identical in appearance. How does placebo effect or expectation bias account for this clear hierarchy in musical quality changes between the two betas and my then owned USB cable when they were each in my system? 

The UK magazine Hi-Fi News had articles in 2013 and 2014 publications (I think July) where they had USB cables double-blinded tested by a panels of skilled listeners  and reported difference in a range of USB cables that they were able to give rank scores to and they also showed variations in the signals passed by each of them in what appeared to be oscilloscope pictures of square waves generated off each of them. Where is the placebo effect and expectation bias here?


----------



## chef8489

UK magazine aimed at audiophiles is far from un biased. They are always trying to sell high end cables. Seriously you have to do better than that. There are just as bad magazines and periodicles in the US and websites. How about all the other hundreds of other tests that were performed out there that shows the opposite, or as stated the professionals in the industry that have stated otherwise. Why does the it industry not have to have expensive cables and gets flawless data transfers, or better yet the US government that I have first hand experience with. When we spend millions on equipment, why don't we need a 1k usb cable to transfer data?


----------



## gregorio

theorist said:


> [1] But you have not answered WHY some USB cables improve the perceived musicality of a system over others USB cables, at least for many listeners.
> [2] Its a question not dissimilar to comparing why a good analogue turntable based system sounds more musical for many listeners to that of an equal or even more expensive pure digital system, even if there are some digital signal stages in the production of the LP being listened to?



1. You're a prof on the philosophy of science right? So, why not take the facts, apply some logic to the problem and figure it out by a process of elimination? The facts are that digital audio is a binary system, one or zero (on/off), there can be no other state, there can be no noisy "1" or clean "1". The only way noise can affect digital audio is if it's so extreme that it changes a one to a zero (or vice versa) but of course that's relatively easy to detect because we would not then have a bit perfect result and all USB certified cables must be able to transfer bit perfect results or they would not be USB cables (or are faulty/broken). Therefore, all you have to do is use the standard USB cable to copy some files and verify the copies and originals are identical, this eliminates both the possibility of a broken USB cable and of extreme noise/interference. Any "parasitic noise" other than noise extreme enough to actually change the values of the zeros and one is already eliminated as a potential cause because it cannot exist in/affect a digital system. You are adamant that nothing else in your system has changed except the USB cable, so that eliminates all the other potential variables except one, your perception. However much you believe that placebo or any other biases cannot be responsible, Conan Doyle's axiom holds true, "Once you eliminate the impossible, whatever remains, no matter how improbable, must be the truth"!

We can also look at the issue the other way around, what properties would a USB cable need in order to improve some property of the sound? Firstly of course it has to actually be able to change the values of the zeros and ones. Just changing the values randomly would result in digital glitches and of course produce a different result every time you played/copied the file, not anything any sane person could describe as an improvement! To avoid just glitches/errors requires specific zeros and ones to be changed in a specific way, this can only be achieved with fairly complex algorithms and computation power. A USB cable is effectively just extruded metal wrapped in some insulation, it does not have any intelligence or embedded digital audio algorithms and the computational power to execute them. Unless one ascribes some totally irrational property to a digital cable, such as magic, there is no real world property a USB cable could have which could achieve the results you are perceiving, which inescapably brings us back again to your perception ... all roads lead to Rome!

2. No, it is entirely dissimilar! Analogue storage and reproduction definitely does change the signal, so significantly that the difference is audible. It is then down to personal preference if one prefers that lower fidelity analogue result. A properly functioning USB cable does not change the data, the data which comes out is identical to the data which goes in. Therefore, with say an LP, you have a personal preference of your perception of actual physically different signals/data but with a USB cable all you have is personal preference of your perception, as there is no difference in the data.

G


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## gregorio

theorist said:


> The UK magazine Hi-Fi News had articles in 2013 and 2014 publications (I think July) where they had USB cables double-blinded tested by a panels of skilled listeners  and reported difference in a range of USB cables ...



I would very much like to see that article, the actual methodology of the tests, the data from those tests and how the conclusions were arrived at. Do you have a link?

G


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## castleofargh

how about we try to take stands that aren't always mutually exclusive and categorical? or even better, stop turning anecdotes into laws? I know I'm asking a lot and it will involve rational thinking which is an often strange concept in amateur audio. 

looking at digital signal through cables as if it's analog isn't necessarily stupid. for one, when the high frequency roll off occurs will be a relevant factor for maximum speed. of course at the same time thinking that making some idealistic square wave signal go rounder in any way will also change the sound is false. like for everything there is a threshold beyond which we take fetal position and wait for things to explode(too dramatic?).but the USB standards(or any electrical standard) was picked because it works fairly well even within pretty big fluctuations and is easy to achieve even with cheap components.
 we can also rebound on this, as there are now many USB standards. a proper USB1 cable isn't the same as a proper USB3 or USBc cable. some usb cables are specifically made for charging devices and nobody cared much about the wires not carrying the 5V DC. as long as the hand shake is done, that's enough for such cables. so not needing a special USB cable might not mean the same as saying we can literally take any USB cable lying around and expect the same specs and behavior. 

 obviously there is the way we treat the usb cable. those moving around to charge our phones can be painful to look at and some people really like to bend solid materials at unreasonable angles for some reason. so let's assume were not talking about those cables suffering from literal PTSD . ^_^

a cable doesn't really do much on it's own, we have to stop silly compartmentalized thinking "look mum, that cable has great soundstage!". instead look at the electrical circuit. but to think that way people need to know a thing or two about electrical components and electricity or it might be an abstract concept. not much can be done about that, we don't know what we don't know. if the cable has electrical properties significantly off from the expected standard, you never know if the devices on each ends have been designed to handle such an abnormal situation. in some extreme cases, it could lead to instability or at least changes in the global electrical behavior. I for one have a fairly clear stand for such a situation. I'll check the cable and do some basic measurements to see if it's broken or within USB specs. if it isn't, bu-bye!!! if it is close enough, I'll blame the gears plugged in it. not try to excuse it with fancy special cables just in case that helps hide a flaw in the gear. same for jitter, noise etc. a DAC is expected to be linked to all sorts of devices in this modern world. the guy who made the design without coming out of his lab with super clean power, perfect voltage to the second decimal, ideal cable and everything into 3 layers of Faraday cages, is an idiot who doesn't deserve our money. that's my view on this. do you guys call a good DAC, one that works great under ideal conditions, or one that can handle most typical issues like a boss? I vote for the later, same as how I pick my camera, computer... I live in real life with real issues and to withstand those issues is why I pay good money. it's obviously not the only way to think, but the more we'll look at pro gear, the more it will be aimed at people who think like me. consistency, stability, they are as, or more important than getting the best result when Jupiter is aligned with Venus and the outside temperature is 17.3°C. if a DAC is garbage under all but the most specific conditions, then it's a garbage DAC. that's my simple view on this. 
having clearly different sounds from different USB cables will make me consider the possibility that I should get another DAC. when for some of you guys it's the enlightened day that "proved" you weren't an idiot to purchase a 1000$ wire for no clear reason. a different mindset clearly plays a part in the resulting conclusions. 

with the same idea, most DACs nowadays have their own fancy special stuff, a specific oversampling value, some proprietary async, reclock, anti jitter, blablah thing. a lot of digital processing for fancy reasons that usually happen to work well. so when a signal is clean, they all do the very best of what they're here to do and we get the ideal results suggested on the specs. 
when it's not clean, they'll maybe have fancy tricks to reduce some issues that other DAC might not have, so right there we might end up with more variations between DACs with a crappy signal than with a clean one. I'm not justifying any idea that cables sound different, this is just food for thought about how variations in the signal could in some cases have consequences that go beyond what a simple wire can do to the signal by itself. and also that maybe if you had a different DAC, your amazeballz cable wouldn't sound so different from that other one. just exploring possibilities. same result different conclusions. 

a personal observation about cables over the years, USB or not, the plugs often make more difference and create more troubles than most fancy crap in the cable. I haven't sampled millions of cables so I won't claim it's always like that, but within what I've tested with my cheap gears, it was so. if I was a real maniac nut-job dead on getting the best audio I can't hear, I'd use rather short cables, cut all the plugs and go solder everything. but I still wouldn't pay 500$ for a USB cable. I hope I can be seen as fairly open minded on this matter, but IMO a USB cable above 100$ is one of those choices:
- a fashion statement. which is very fine and not dumber than a 5000$ hand bag or a 2 million car. some rich people need stuff to show they're rich to other people. if I was rich I'd get some of those.
- a trap for fools. 
- a specific cable for one of those stuff you need once in a lifetime, like for something on a spaceship that can handle cosmic rays, or a usb cable to be plugged near the cyclotron while it's ON. you know weird cable for weird needs. 

I can't think of anything requiring more than a few bucks of material and manufacturing. the idea that a lot will be hand made can justify higher price but is IMO a weakness for the cable as it implies much lower consistency than an automated process. so unless I get a unique set of extensive measurements coming with my cable and showing how much better it is, why would I pay extra anything? it's not being blind to the possible improvements of cables. it's trying not to be blind to the realities of commerce. if a guy can trick me into believing some not special cable is special, he'll do just that and increase his price and margin. ask for evidence, if the guy claims technical superiority, where is the objective evidence shown measuring the very cable he's trying to sell to me? the "just listen" mantra is nice to decide that I can't stand Despacito, it's not an argument for technical expertise. in fact I tend to be biased and take all the guys selling gears and saying "just listen" to be crooked. objective claims of fidelity require objective evidence, not subjective excuses.
and if they wish to make claims of subjectively nicer sound, I'm fine with that, after all if I like something I don't care about anything else. but then don't lie about increased fidelity without any evidence of it. 

to end this rant on wider issue, we all need to stop taking whatever anecdotal event fell on our lap as if it redefines the laws of physics. it's a fracking wire! once I wore a green shirt and got bitten by a parrot. less than a year later I got bitten by a monkey on the same finger while wearing that same green shirt. I leave you to draw the right conclusions about green shirts, exotic animals, and your favorite usb cable anecdotes.  we usually see and hear what we want to see and hear.


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## theorist

gregorio said:


> I would very much like to see that article, the actual methodology of the tests, the data from those tests and how the conclusions were arrived at. Do you have a link?



I read the magazine articles in hardcopy. But a Google search of 'Hi-Fi News USB cable blind" gives quite a few links to discussions about the articles and a Nordost link to a reprint of one of them (you asked me for a link so please don't spam me for using a manufacturer's website to supply it !) at: 
http://www.nordost.com/images/review-images/review-pdf/HFN_USB Cable GT July.pdf


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## theorist

gregorio said:


> "Once you eliminate the impossible, whatever remains, no matter how improbable, must be the truth"!



Or there is something else present that we are unaware of because it does not fit our current paradigm !


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## Clive101 (Sep 3, 2017)

Firstly I wanted to use a less expensive USB cable and was bias as I do not want to watse money and I used the standard cable suppied with a the Chord Dave and using a laptop ( on battery ) windows 10 for music JRiver. USB leads did make the difference.

Long story short same laptop windows 7 SQ not quite as good and USB leads did not make a noticeable difference ( very little but could not certain between cables with any reliableablity including ultra expensive ).

I can only trust all the people who do not notice a difference are correct with their equipment and believe them, if I were to listen to their equipment  I would come to the same conclusion.

I use a power conditioner with different USB cables and the difference between USB cables was closer while using the power conditioner.

Using a melco na1Z improved the SQ further.

I have no tech knowledge and agree that zeros and ones cannot be changed but coild it be noise or rf or something gets passed between sources...?

Could it be different cables are able to cope with this interferance and not pass onto the DAC which in turn passes on to the amps etc....?

There are a number people who agree upstream equipmet of the Dave make a difference again zeros and ones...?

Different DAC may well be different hence apples and pears.

I also disconnected my melco from the network, background noise reduced ( off topic ).

In essence I wanted a USB cable supplied with the Dave to work and did not want to spend extra money on melco or a fancy USB cable to impress friends ( none of which know the cost of my system but like the sound ) etc.

Hope that helps people reading this thread please do not shoot me down, I am not interested in the placebo effect unless you can hypnotize me...!


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## Currawong (Sep 3, 2017)

chef8489 said:


> There is no parasitic noise coming over a usb cable. There is no noise coming over a usb cable.



Yes, noise aside from the signal can go across a digital cable. Recent USB receiver circuit designs eliminate this. The other factor is that the USB receiver chips can themselves output unwanted noise. This has to be filtered out from the digital signal inside the DAC as well (or externally if using a converter of some sort) if it is to not potentially interfere with the final analog output.

Unfortunately there doesn't seem, at least yet, to be any directly measured artifact that can be attributed to these things, probably due to the large number of variables involved. That it why it comes down to what people hear. The closest thing we have to any kind of correlation is that designs better isolated from noise seem, in general, to be reported as sounding better.

I have to say, also, that making rude declarations about people because one disagrees about a person's experience is not science, but a form of fanaticism on the same level as held by the person vigorously arguing the opposite opinion with which one disagrees.


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## gregorio (Sep 4, 2017)

theorist said:


> I read the magazine articles in hardcopy. But a Google search of 'Hi-Fi News USB cable blind" gives quite a few links to discussions about the articles and a Nordost link to a reprint of one of them (you asked me for a link so please don't spam me for using a manufacturer's website to supply it !) at: http://www.nordost.com/images/review-images/review-pdf/HFN_USB Cable GT July.pdf



Thanks for the link. It is rather bizarre in terms of your comments though. Firstly, nowhere does the article mention it was a double-blind test as you described it. There is a very significant difference between blind and double blind tests, so much so, that blind tests are not accepted in say medical research or pretty much any branch of science. How is it possible for you, a uni prof, not to know this? There was no explanation of the methodology of the tests, so no way to determine/evaluate if it was even a bona fide blind test, let alone how affected by biases the test was, even if it were a bona fide blind test! There was also no explanation of how the data was obtained, the data itself was not published, nor was how it was analysed and therefore we have no idea how or even if the published conclusions/reviews correlate with that data. All that's been provided is an edited collation of the testers' subjective opinions, which demonstrates nothing, not even that there were any audible differences between cables! For example, during each tester's testing was each test always a different cable or did some of the tests use the same cable as the previous test (unknown to the tester)? If it was the former, then that knowledge alone is enough to introduce so much bias as to invalidate the test, regardless of the tester being unaware of which different cable they were listening to. You stated of this article "_Where is the placebo effect and expectation bias here?_" Again, how as a uni prof of science philosophy is it possible for you to even ask this question, let alone use it to support your assertion? It indicates little/no understanding of what the scientific method is or why it exists!

I will commend the article for providing some actual measurements, a rarity in cable marketing. Although unfortunately, it's not explained that these measurements are effectively useless/irrelevant! A USB cable's job, by definition, is to transfer a USB specification signal. The rise times (properties of the eye pattern) are irrelevant, provided they are within the USB specification. It is incumbent on the USB receiving equipment (in this case a USB DAC) to accurately extract the data from a USB specified signal, regardless of it's rise time! If a USB DAC performs more accurately with a faster rise time than with a slower rise time, providing both rise times are within the USB specification, then the DAC is not compliant with USB specifications (is faulty)! The exception to these irrelevant measurements was the one for the Signal Projects Lynx Reference USB cable, which, if the measurement was accurate, demonstrates that is cable is NOT a USB cable! Astonishing, even sub $10 cables are capable of meeting USB specifications but apparently not this audiophile cable costing 100 times more?! The fact that it even works without serious errors is testament to the fact that DACs must be relatively insensitive to rise times, even if they fall outside the USB specification. Of course the review they publish ("free-form" section) is complete nonsense, digital audio cannot be louder or quieter without applying one or more algorithms to significantly change the bit values, as already explained.



theorist said:


> Or there is something else present that we are unaware of because it does not fit our current paradigm!



Again, simple logic! If there were something present that we are unaware of, then we can't measure it and therefore can't record it, digitize it, undigitize it or reproduce it!

G


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## JJF_888

Great timely topic!


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## JJF_888

gregorio said:


> For example, there's a music genre called counterpoint which relies on what's called "implied harmony", harmony which isn't actually there in the music but which the brain predicts/invents itself, hence "implied" harmony. JS Bach was the master of counterpoint and he (and all other composers) was manipulating/fooling what listeners were certain their ears were telling them 300 years ago!



Do you have a reference for learning more about this? TIA!


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## JJF_888

Can any of the audiophile magazines be viewed as credible or something other than advertising platforms?


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## gregorio

JJF_888 said:


> Do you have a reference for learning more about this? TIA!



Not off the top of my head, I studied counterpoint over 30 years ago, before there was a web! I can't even remember the text books we used, although one was by someone with the surname of Fux. Contrary to what I stated before, counterpoint isn't really a musical genre as such but a compositional technique/style. The pinnacle of that technique is to be found during the high baroque in the musical form known as the Fugue, although counterpoint dates back at least a couple of hundred years earlier. I'm sure if you typed; counterpoint and implied harmony, into google you find something useful.

G


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## JJF_888

Thanks!


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## JJF_888

Would putting a simple ferrite choke, or one on each end of the USB, remove the potential of any power supply noise?


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## Arpiben

gregorio said:


> Thanks for the link. It is rather bizarre in terms of your comments though. Firstly, nowhere does the article mention it was a double-blind test as you described it. There is a very significant difference between blind and double blind tests, so much so, that blind tests are not accepted in say medical research or pretty much any branch of science. How is it possible for you, a uni prof, not to know this? There was no explanation of the methodology of the tests, so no way to determine/evaluate if it was even a bona fide blind test, let alone how affected by biases the test was, even if it were a bona fide blind test! There was also no explanation of how the data was obtained, the data itself was not published, nor was how it was analysed and therefore we have no idea how or even if the published conclusions/reviews correlate with that data. All that's been provided is an edited collation of the testers' subjective opinions, which demonstrates nothing, not even that there were any audible differences between cables! For example, during each tester's testing was each test always a different cable or did some of the tests use the same cable as the previous test (unknown to the tester)? If it was the former, then that knowledge alone is enough to introduce so much bias as to invalidate the test, regardless of the tester being unaware of which different cable they were listening to. You stated of this article "_Where is the placebo effect and expectation bias here?_" Again, how as a uni prof of science philosophy is it possible for you to even ask this question, let alone use it to support your assertion? It indicates little/no understanding of what the scientific method is or why it exists!
> 
> I will commend the article for providing some actual measurements, a rarity in cable marketing. Although unfortunately, it's not explained that these measurements are effectively useless/irrelevant! A USB cable's job, by definition, is to transfer a USB specification signal. The rise times (properties of the eye pattern) are irrelevant, provided they are within the USB specification. It is incumbent on the USB receiving equipment (in this case a USB DAC) to accurately extract the data from a USB specified signal, regardless of it's rise time! If a USB DAC performs more accurately with a faster rise time than with a slower rise time, providing both rise times are within the USB specification, then the DAC is not compliant with USB specifications (is faulty)! The exception to these irrelevant measurements was the one for the Signal Projects Lynx Reference USB cable, which, if the measurement was accurate, demonstrates that is cable is NOT a USB cable! Astonishing, even sub $10 cables are capable of meeting USB specifications but apparently not this audiophile cable costing 100 times more?! The fact that it even works without serious errors is testament to the fact that DACs must be relatively insensitive to rise times, even if they fall outside the USB specification. Of course the review they publish ("free-form" section) is complete nonsense, digital audio cannot be louder or quieter without applying one or more algorithms to significantly change the bit values, as already explained.
> 
> ...



Fully agreeing on the useless/irrelevant character of the measurements provided in the mentioned paper.
I will just add the following:

no indication of measurement plane & test bench ( USB Host (DAP) - USB Cable-* 'Probe'*- USB Device (DAC)?)
Eye patterns are performed at U.I.= 80ns ( 12.5 Mbps Full Speed specifications) not at  U.I.= 2.08 ns (480 Mbps High.Speed).
Length of every USB cable not provided
Test files 44.1kHz/16bit  (~1.4Mbps) and 176.4kHz/24bit (~8.5Mbps) but no eye pattern at those rates
USB cables' impedance characteristic not measured but "estimated" with eye pattern at imho not usefull frequency.
 Rgds


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## theorist (Sep 4, 2017)

In his book ‘_The Structure of Scientific Revolutions’_ Thomas Kuhn (1962) defines a scientific paradigm as:

_what_ is to be allowed to  be observed and scrutinized;
the kind of _questions_ that are permitted to be asked and tested for answers in relation to the subject under investigation;
_how_ these questions must be structured, and;
_how_ the results of scientific investigations must be interpreted.
When a paradigm is starting to breakdown anomalies occur that are not thinkable under the dominant/hegemonic paradigm. Anything that does not fit the orthodoxy of the paradigm as defined by the above criteria are dismissed by the scientific defenders of that orthodoxy as bizarre, irrelevant, wrong, deluded, inconceivable, ignorant or misinterpreting/ misunderstanding, impossible, extremist; or, by making statements such as: ‘no logics and facts will persuade you that you are wrong’ or ‘you can’t provide measurements showing this’, etc. If you go back through the discussions in this topic forum, you will see these words/clauses are used repeatedly throughout by a few defenders of IT signal ‘perfection’ orthodoxy when I or someone else say that they hear differences in their systems when changing  USB or other digital cables such as ethernet ones.

Indeed, following Kuhn (1962) theory changes in science or anywhere else in what is called knowledge, are not fundamentally an accumulation of facts, but rather a change of ways of intellectually conceiving concepts and ways of understanding the world. Some people are fixed in their ways and don’t wish to engage with change in their worldview. So, if people believe that their theories say that USB cables cannot affect the sound of music being produced in an audio system is this not then expectation bias of the highest order? Accordingly, they won’t hear any change, even in a double-blind test, because they _know _that they cannot be any – and they have the theory to ‘prove’ this. Others of us, without this believe, may, of course, hear changes, at least when change occurs. And while I cannot speak for others, I have heard differences between USB cables in my system, sometimes this is obvious and immediately audible, in other cases much more subtle and only apparent over time and with reflection. And, yes, at least for me, there is a general correlation between digital cable cost and perceived signal/music quality improvement in my system, but this is not necessarily always the case between different cables, and this correlation is probably stronger within a brand’s own product range than across different brands, perhaps indicative of the strength of the design principles being used by different companies.


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## Clive101

Not off topic ( but close ) the issue of noise within systems.
https://www.head-fi.org/threads/chord-electronics-blu-mk-2-the-official-thread.831343/page-93
Some well regarded people, the post by Romaz is of particular interest earlier posts of USB cables are also of interest (same person).


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## theorist

Clive101 said:


> Not off topic ( but close ) the issue of noise within systems.
> https://www.head-fi.org/threads/chord-electronics-blu-mk-2-the-official-thread.831343/page-93
> Some well regarded people, the post by Romaz is of particular interest earlier posts of USB cables are also of interest (same person).



Yes, despite what some may claim, the average PC is really pretty noisy, not in an analogue sense of noise, but in what to me is largely I consider musical 'glare'. Some people describe it metaphorically as 'looking' at your music as though through dirty or distorted glass. That's why I have an Antipodes DX (its also not too expense in NZ as its made here). As described by Romaz, Mark has built these servers after lots of listening tests to select and then layout: 1) really good clean power supplies, 2) lowest noise SSDs, and 3) to have component/layout/operating software set up and operating in a manner that attempts to 'tune' this computer noise in its various components so that it is minimised and less intrusive in the overall music. Even Audirvana or Amarra software designed as Mac or PC music processors try and optimise the back-ground tasks (or turn them off)  in your computer to minimise the noise that they generate that gets picked up in the digital signals carrying your music data.

Undoubtedly, some of  the  trolls will come back and attempt to trash this heresy of their 'properly implemented digital sound must always be perfect' orthodoxy, but don't believe them, listen with 'open' ears and decide for yourself!


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## Arpiben

Clive101 said:


> Not off topic ( but close ) the issue of noise within systems.
> https://www.head-fi.org/threads/chord-electronics-blu-mk-2-the-official-thread.831343/page-93
> Some well regarded people, the post by Romaz is of particular interest earlier posts of USB cables are also of interest (same person).



For sake of objectivity, you should also quote or remind the numerous posts of your DAC designer ( Chord / Rob Watts).
He has been repeatedly posting that USB / BNC digital cables do not make differences!
According to him, RF currents circulating in those cables, may affect SQ due to noise floor modulation.


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## Clive101 (Sep 5, 2017)

Arpiben said:


> For sake of objectivity, you should also quote or remind the numerous posts of your DAC designer ( Chord / Rob Watts).
> He has been repeatedly posting that USB / BNC digital cables do not make differences!
> According to him, RF currents circulating in those cables, may affect SQ due to noise floor modulation.


Thanks for the mention of Robs Watts ( an expert ) he did reply to an earlier post of mine re the same USB issue.
He is always open minded, and his recent post on cables with ferrite cores is interesting digital zeros and ones being transferred between Dave and Blu mk2 on cables seems to support the noise issue.
Have a quick read.
https://www.head-fi.org/threads/chord-electronics-blu-mk-2-the-official-thread.831343/page-87
Thank you for the reply


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## Clive101

theorist said:


> Yes, despite what some may claim, the average PC is really pretty noisy, not in an analogue sense of noise, but in what to me is largely I consider musical 'glare'. Some people describe it metaphorically as 'looking' at your music as though through dirty or distorted glass. That's why I have an Antipodes DX (its also not too expense in NZ as its made here). As described by Romaz, Mark has built these servers after lots of listening tests to select and then layout: 1) really good clean power supplies, 2) lowest noise SSDs, and 3) to have component/layout/operating software set up and operating in a manner that attempts to 'tune' this computer noise in its various components so that it is minimised and less intrusive in the overall music. Even Audirvana or Amarra software designed as Mac or PC music processors try and optimise the back-ground tasks (or turn them off)  in your computer to minimise the noise that they generate that gets picked up in the digital signals carrying your music data.
> 
> Undoubtedly, some of  the  trolls will come back and attempt to trash this heresy of their 'properly implemented digital sound must always be perfect' orthodoxy, but don't believe them, listen with 'open' ears and decide for yourself!



Yes that Antipodes DX does look like a nice piece of kit did you compare with anything else before purchase  and to be on topic how did the noise compare on the USB cable..?
I may be in the market to one ..?


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## gregorio

theorist said:


> [1] When a paradigm is starting to breakdown anomalies occur that are not thinkable under the dominant/hegemonic paradigm.
> [2] I or someone else say that they hear differences in their systems when changing  USB or other digital cables such as ethernet ones.
> [3] So, if people believe that their theories say that USB cables cannot affect the sound of music being produced in an audio system is this not then expectation bias of the highest order?
> [4] Others of us, without this believe, may, of course, hear changes, at least when change occurs.
> [5] And, yes, at least for me, there is a general correlation between digital cable cost and perceived signal/music quality improvement in my system ...



1. What paradigm is starting to breakdown? I don't see the digital age ending because digital doesn't work, I see the exact opposite!
2. So, we've got a few thousand audiophiles making unsubstantiated claims that the transfer of digital data is flawed and on the other side we've got mathematical proof that perfect data transfer is possible, countless actual measurements which prove it's not just possible but standard and most of the rest of the world's population who rely on this fact.
3. Yes ... but of course we are NOT talking about a theory. We are taking about a mathematically proven theorem, countless actual measurements and probably the most demonstrated and relied upon fact in human history!!! How as even an averagely educated, rational person can you not know the difference, let alone as a uni prof?
4. No one is disputing that you hear a change! What we're disputing is what is causing that change. You are basing your explanation/claim purely on your perception of what you think you're hearing and effectively pitting your trust in your perception against the mathematical proof, the measured data and the demonstrated facts. How is that even possible for a self proclaimed uni prof, it's not even acceptable for high school student?!
5. As the article you linked to demonstrated, under certain circumstances there could be a correlation. The Lynx USB cable does not apparently adhere to it's stated specifications and in this case the correlation between price and quality would be higher price = lower quality, not at all an uncommon occurrence in the audiophile world and it works because many audiophiles appear to prefer lower fidelity. 

You seem fond of quoting scientific philosophy while at the same time ignoring the absolute basics. You have two facts (different cable, different perception) and are making a correlation between them without evidence, a classic logical fallacy. For example, it's fact that more people drown in summer, it's also fact that more ice cream is consumed in summer but it would be a logical fallacy to state that therefore consuming ice cream causes drowning! Until you can demonstrate that the difference isn't just a consequence of your flawed perception then all you're doing is repeating the same logical fallacy! If you're going to quote science philosophy then you can't only quote the bits of it which could potentially support your unsubstantiated claims, here's one of the most famous bit's of scientific philosophy, "_Extraordinary claims require extraordinary evidence_". You are claiming that perfect digital transfer is impossible, therefore that the mathematical proof must be incorrect, as must the countless actual measurements and therefore effectively that the digital age which relies on these facts cannot exist, all of which is about as extraordinary a claim as it's possible to make! And what is your most extraordinary evidence for your most extraordinary of claims? Apparently nothing more than your personal perception of what you're hearing, that of a handful of other extreme audiophiles and some marketing materials aimed at said audiophiles! Really? And you're purporting to be a uni prof in science philosophy??



theorist said:


> [1] Yes, despite what some may claim, the average PC is really pretty noisy, not in an analogue sense of noise, but in what to me is largely I consider musical 'glare'. Some people describe it metaphorically as 'looking' at your music as though through dirty or distorted glass. ... Even Audirvana or Amarra software designed as Mac or PC music processors try and optimise the back-ground tasks (or turn them off)  in your computer to minimise the noise that they generate that gets picked up in the digital signals carrying your music data.
> [2] Undoubtedly, some of  the  trolls will come back and attempt to trash this heresy of their 'properly implemented digital sound must always be perfect' orthodoxy, but don't believe them, listen with 'open' ears and decide for yourself!



1. The vast majority of digital data is not music, so what happens to all those other zeros and ones which do not represent music, does they have musical "glare" too, is that like looking through "dirty or distorted glass". Does the world need Audirvana or Amarra software in order for computers to function accurately and for the digital age to exist?
2. Undoubtedly, some trolls (and shills), who put what they think they're hearing above proven maths, actual measurements, all the reliable tests and of course the facts which have been demonstrated countless trillions of times a second for many years, will try and convince you to do the same, any vaguely rational person should not need telling NOT believe them!! 

G


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## theorist

Clive101 said:


> Yes that Antipodes DX does look like a nice piece of kit did you compare with anything else before purchase  and to be on topic how did the noise compare on the USB cable..?
> I may be in the market to one ..?



Actually I did not compare the DX to other kit, I had heard an Antipode DS in a near identical system to mine and was impressed in how 'clean' the music sounded compared to my Mac running Amarra. When the strong reviews for the DX came out a couple of years ago, I just went for it after a listen that found it significantly better than the DS in regard to the palpability of the music it presented, ie little, if any, 'digital glare'. Largely, this was also because the NZ price of NZ kit here is generally 30% less than its cost overseas and all imported kit here is about 30% more expensive than say its US price, so it becomes a no-brainer to buy good local kit here like Plinius or Antipodes, because of its significant price advantage. To answer your other question, the impact of any good dedicated music server will be much greater in cleaning up digital 'glare' in a system over the improvement made by the purchase of any USB cable. Indeed, I suspect, that one of the reasons people claim to hear no difference between printer USB cables and dedicated quality audio USB cables are that they are using noisy computers for their source that  literally 'drown-out' in glare the small by comparison, but still significant, improvement made by a well designed cable. 

I think a lot of people, even some Head-Fliers, don't seem to get the basic premise of the interest of audiofiles to try and get as close as possible to the 'absolute sound' even when we know that this is impossible (just think of the latency (inertia/slew rate) of all recording microphones). But it does rather amuse me when some equate the accuracy of a digital code to produce the correct bit of hex code (or whatever) to represent, say, the letters of the alphabet, which is rather different than the nuanced information necessary to accurately reproduce the timbre, timing and other characteristics of palpable music that audiofiles are attempting to achieve (the spaces between the notes -- after Miles Davis). And no doubt the 'digital is already perfect' science types will profoundly disagree, but they are entitled to their believes, just as we are. 

Indeed, I don't draw on 'scientific philosophy', but I do use philosophy. My philosophical perspective considers science a useful human construct, but one which ultimately is just a _method_ for testing the validity of repeatable patterns in the natural world, that is, provided that these patterns are not too complex and non-linear, or even random, at least as defined by our state of knowledge, in their affect. But this often very useful and sometimes sophisticated method  cannot constitute truth-in-itself and to believe that it does is simply to reify it as a deity (after Nietzsche). And, I am afraid, some people do tend to place science falsely on this profound pedestal as the ultimate guarantor of truth.


----------



## JJF_888

Out of curiosity, have you tried a simple ferrite choke on the USB cables to see if they offer a similar change? That would be helpful to know as, I for one, believe in noise issues that can be discernible.


----------



## theorist

JJF_888 said:


> Out of curiosity, have you tried a simple ferrite choke on the USB cables to see if they offer a similar change? That would be helpful to know as, I for one, believe in noise issues that can be discernible.



I have experimented with ferrite chokes over the years and while fun and inexpensive to do so, I have never felt that they have made a significant and/or consistent difference anywhere from power cables to digital cables and everything in between!


----------



## Clive101

theorist said:


> Actually I did not compare the DX to other kit, I had heard an Antipode DS in a near identical system to mine and was impressed in how 'clean' the music sounded compared to my Mac running Amarra. When the strong reviews for the DX came out a couple of years ago, I just went for it after a listen that found it significantly better than the DS in regard to the palpability of the music it presented, ie little, if any, 'digital glare'. Largely, this was also because the NZ price of NZ kit here is generally 30% less than its cost overseas and all imported kit here is about 30% more expensive than say its US price, so it becomes a no-brainer to buy good local kit here like Plinius or Antipodes, because of its significant price advantage. To answer your other question, the impact of any good dedicated music server will be much greater in cleaning up digital 'glare' in a system over the improvement made by the purchase of any USB cable. Indeed, I suspect, that one of the reasons people claim to hear no difference between printer USB cables and dedicated quality audio USB cables are that they are using noisy computers for their source that  literally 'drown-out' in glare the small by comparison, but still significant, improvement made by a well designed cable.
> 
> I think a lot of people, even some Head-Fliers, don't seem to get the basic premise of the interest of audiofiles to try and get as close as possible to the 'absolute sound' even when we know that this is impossible (just think of the latency (inertia/slew rate) of all recording microphones). But it does rather amuse me when some equate the accuracy of a digital code to produce the correct bit of hex code (or whatever) to represent, say, the letters of the alphabet, which is rather different than the nuanced information necessary to accurately reproduce the timbre, timing and other characteristics of palpable music that audiofiles are attempting to achieve (the spaces between the notes -- after Miles Davis). And no doubt the 'digital is already perfect' science types will profoundly disagree, but they are entitled to their believes, just as we are.
> 
> Indeed, I don't draw on 'scientific philosophy', but I do use philosophy. My philosophical perspective considers science a useful human construct, but one which ultimately is just a _method_ for testing the validity of repeatable patterns in the natural world, that is, provided that these patterns are not too complex and non-linear, or even random, at least as defined by our state of knowledge, in their affect. But this often very useful and sometimes sophisticated method  cannot constitute truth-in-itself and to believe that it does is simply to reify it as a deity (after Nietzsche). And, I am afraid, some people do tend to place science falsely on this profound pedestal as the ultimate guarantor of truth.


Thanks for the reply re the DX.
I have no doubt about the noise issue in the equipment and the reaction with the cable, some cables reacting better to noise than others.
Obviously the equipment matters as you say.
Regards


----------



## gregorio

theorist said:


> I think a lot of people, even some Head-Fliers, don't seem to get the basic premise of the interest of audiofiles to try and get as close as possible to the 'absolute sound' even when we know that this is impossible (just think of the latency (inertia/slew rate) of all recording microphones). But it does rather amuse me when some equate the accuracy of a digital code to produce the correct bit of hex code (or whatever) to represent, say, the letters of the alphabet, which is rather different than the nuanced information necessary to accurately reproduce the timbre, timing and other characteristics of palpable music that audiofiles are attempting to achieve (the spaces between the notes -- after Miles Davis).



To the rest of humanity, flat-earthers are just nutters who are obviously ignorant of the science, maths and demonstrated facts but this view isn't entirely correct. Flat-eathers look through their windows, see that the earth is flat and trust absolutely what their eyes are telling them. It's not that they're unaware of the science, maths and actual facts, it's that they're too stupid and/or poorly educated to fully appreciate them and because they trust what their eyes are telling them then the science, maths, demonstrated facts or anything else which disagrees with what they see and know to be correct, must be wrong! After all, science is fallible, it doesn't know everything, maybe there's something it's not yet aware of? To a flat-earther it is the rest of us who are nutters, what is wrong with us, why don't we just look out of our windows and see the truth for ourselves? Do flat-earthers just have better eyesight than the rest of us, are the rest of us blind ... or maybe we have poorer quality glass in our windows which obscures what we're able to see, maybe we need flat-earth grade windows which are 100 times more expensive than ordinary windows, in order to properly see that the earth is flat? What university would appoint a flat-earther as a prof of scientific philosophy ... maybe Trump University?



theorist said:


> But it does rather amuse me when some equate the accuracy of a digital code to produce the correct bit of hex code (or whatever) to represent, say, the letters of the alphabet, which is rather different than the nuanced information necessary to accurately reproduce the timbre, timing and other characteristics of palpable music that audiofiles are attempting to achieve (the spaces between the notes -- after Miles Davis)..



Not as much as it amuses me to see some audiophiles inventing ridiculous nonsense based on poor understanding and apparently deliberate logical fallacy to justify their effectively flat-earth views. To respond to your point, yes the alphabet is fairly easy to represent digitally but so is an analogue electrical current, which only comprises two physical properties; amplitude and frequency. The palpable nuances of music are just a function of those two properties, just as say a Shakespeare sonnet has palpable nuances which are just a function of the 26 letters of the alphabet. Can digital technology only accurately handle simple texts and emails to your mates, can it not accurately handle the "nuanced information" and "other characteristics" of the world's "palpable" poetry and literature?

The problem with being a flat-earther is that they have to enter a logical black hole and make up ludicrous irrational explanations for the consequences of their belief. For example, there must be some irrational explanation for what happens at the edge of this flat earth, some mystical, magical properties/processes going on. It's the same for that small sub-group of extremist audiophiles, a simple piece of extruded metal must have magical properties, it must not only know that the zeros and ones (on/off voltage) it's transferring represents music but it must understand what musicality is and apply it to those zero and ones. That is as about as absurd as it gets for any rational person but for someone who trusts what their ears are telling them above any demonstrated fact, science or proven maths, then however absurd, it's apparently believable. This brings us right back to the two response options I gave you pages ago, you've obviously decided to go with the completely irrational/illogical option. Which is more than a little shocking for someone claiming to be a uni prof in science philosophy!

G


----------



## Currawong

gregorio said:


> Not as much as it amuses me to see some audiophiles inventing ridiculous nonsense based on poor understanding and apparently deliberate logical fallacy to justify their effectively flat-earth views.



It's not as bad as people espousing incomplete science or selected facts as the one and only truth, or using association fallacies to attack people with whom one disagrees, IMO.


----------



## gregorio

Currawong said:


> It's not as bad as people espousing incomplete science or selected facts as the one and only truth, or using association fallacies to attack people with whom one disagrees, IMO.



If, as I take it, you are referring to me, then how is that worse than espousing completely made up "facts" and/or "facts" with no reliable evidence whatsoever (and which contradict the science and demonstrable facts) as the one and only truth and using fallacies to attack people with whom one disagrees, in your opinion? If what I've stated is incomplete, it's only due to the obvious need to hugely simplify for those who apparently do not understand even the fundamental basics of digital data.

G


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## Arpiben

Clive101 said:


> Thanks for the mention of Robs Watts ( an expert ) he did reply to an earlier post of mine re the same USB issue.
> He is always open minded, and his recent post on cables with ferrite cores is interesting digital zeros and ones being transferred between Dave and Blu mk2 on cables seems to support the noise issue.
> Have a quick read.
> https://www.head-fi.org/threads/chord-electronics-blu-mk-2-the-official-thread.831343/page-87
> Thank you for the reply



Thanks for the link.
Ferrites are acting as Low Pass Filter attenuating unwanted frequencies from and to a device.
The difficulty (without instrumentation) is to determine the unwanted frequency value or range. 
In your example the RFI getting out from the DAC/Blu should be well known by the manufacturer.
The RFI coming from the environment where the DAC/Blu seats is unknown.

Ferrite chokes should be considered as workarounds,IMO.
Ferrite beads at equipment pcb level, proper RFI/EMI rejection or proper grounding are preferable.


----------



## JJF_888

theorist said:


> I have experimented with ferrite chokes over the years and while fun and inexpensive to do so, I have never felt that they have made a significant and/or consistent difference anywhere from power cables to digital cables and everything in between!



What can you attest to as the reason for the sound differences in the cable then? That is what is of interest to many of us here as the audio world is, in many many ways, a DYI paradise/hell.


----------



## Clive101

Arpiben said:


> Ferrite chokes should be considered as workarounds,IMO.
> Ferrite beads at equipment pcb level, proper RFI/EMI rejection or proper grounding are preferable.


Yes agreed, the noise should not be there in the first place, I have yet to purchase the blu 2 or stand alone mscaler if it gets produced.
Before I do I will test with different cables as I have a Torus perhaps that may help with noise issue.
Rob Watts does identify the correct type of ferrite bead that helps with the issue, it will be interesting to know how the other people get on with the expensive cables vs the cheap cables with the ferrite beads...?
As always I preferred the cheaper option let's how it pans out.


----------



## castleofargh

theorist said:


> Actually I did not compare the DX to other kit, I had heard an Antipode DS in a near identical system to mine and was impressed in how 'clean' the music sounded compared to my Mac running Amarra. When the strong reviews for the DX came out a couple of years ago, I just went for it after a listen that found it significantly better than the DS in regard to the palpability of the music it presented, ie little, if any, 'digital glare'. Largely, this was also because the NZ price of NZ kit here is generally 30% less than its cost overseas and all imported kit here is about 30% more expensive than say its US price, so it becomes a no-brainer to buy good local kit here like Plinius or Antipodes, because of its significant price advantage. To answer your other question, the impact of any good dedicated music server will be much greater in cleaning up digital 'glare' in a system over the improvement made by the purchase of any USB cable. Indeed, I suspect, that one of the reasons people claim to hear no difference between printer USB cables and dedicated quality audio USB cables are that they are using noisy computers for their source that  literally 'drown-out' in glare the small by comparison, but still significant, improvement made by a well designed cable.
> 
> I* think a lot of people, even some Head-Fliers, don't seem to get the basic premise of the interest of audiofiles to try and get as close as possible to the 'absolute sound' even when we know that this is impossible (just think of the latency (inertia/slew rate) of all recording microphones).* But it does rather amuse me when some equate the accuracy of a digital code to produce the correct bit of hex code (or whatever) to represent, say, the letters of the alphabet, which is rather different than the nuanced information necessary to accurately reproduce the timbre, timing and other characteristics of palpable music that audiofiles are attempting to achieve (the spaces between the notes -- after Miles Davis). And no doubt the 'digital is already perfect' science types will profoundly disagree, but they are entitled to their believes, just as we are.
> 
> Indeed, I don't draw on 'scientific philosophy', but I do use philosophy. My philosophical perspective considers science a useful human construct, but one which ultimately is just a _method_ for testing the validity of repeatable patterns in the natural world, that is, provided that these patterns are not too complex and non-linear, or even random, at least as defined by our state of knowledge, in their affect. But this often very useful and sometimes sophisticated method  cannot constitute truth-in-itself and to believe that it does is simply to reify it as a deity (after Nietzsche). And, I am afraid, some people do tend to place science falsely on this profound pedestal as the ultimate guarantor of truth.



TBH this is a real issue for me. mainly because people discuss audio details in terms of how important they are for them, not in regard to objective magnitudes or even in reference to some other part of the playback chain. we end up discussing a very real sound the way we would discuss emotions. someone loses and arm, his biggest problem is losing an arm and he has strong emotions. a kid didn't get the new Iphone, at the moment for him it is the worst thing in his life, he certainly has very strong emotions. they are not fake, he is not pretending.  but of course placed in front of the guy losing his arm as the new reference, we can only see this as a joke. it's a matter of reference. and emotions are bad at putting things into perspective. they often up like that, with 2 people thinking just as strongly about 2 things magnitudes apart in reality. and it is what's happening when most people come telling me that they got night and day better audio with the new fancy USB cable.  it's not even about doubting an audible difference. that could or couldn't have happened, I wasn't there so I couldn't say. it's the massive exaggeration of everything while offering no evidence that makes me dismiss it as a kid who wants the iphone.
with my crappy yet non defective 10$ USB cable, I can still measure most stuff down to -100db, and that's with the analog loop and DAC to ADC. I don't know for sure that the guy who's talking about his USB cable also had that clean a system to begin with, or maybe he had indeed a USB cable way out of specs. but as my system is really nothing special, I expect he does. because if throwing money at gears ends up doing worst fidelity than my really basic system, something is really wrong with high end audio. so I expect that I'll be right to assume the guy either has good enough gears, or if he doesn't, I'm right not to take his claims of fidelity seriously.
so I admit I come with some assumptions. I expect the digital signal to typically be almost error free as it most likely is, I expect the noise levels to be fairly low because there shouldn't be anything making like 2V of noise in the cable. that would be weird and unusual. in the end I expect the guy making his claim about night and day better sound with the USB cable, to have from the start a fairly functional system. so when he goes raving about how important he feels the new USB cable to be, I can't help but look at the headphone and think "I know poor thing, they don't see your missing arm, I'm so sorry".


 the biggest mistake I see in your posts is that you keep trying to argue about digital stuff as counterpoint to your opinion. how you don't seem to know much about it should tell you better, but that's where we are. it is probably, and the others are right about that, the last place where we'll get fidelity issues. so you're attacking the wrong angle IMO. at the same time it doesn't mean that other issues can't affect a DAC. the noise while probably irrelevant for most modern ways to read digital values and check them, can creep into the rest of the DAC. power supply or analog paths. they are not digital issues but they could be issues. and maybe sometimes a special shielded cable or a cable with a low pass filter will for some specific design facing a specific problem, really improve some stuff. I'm open to that idea and many others. and it's certainly trivial to just measure my system in a loop with different cables or a ferrite bead like I did a few times, and see objective evidence that the given USB cables have an impact on the final sound of the given DACs in my system.
 the magnitudes and how audible that is, it's another matter. as for knowing the cause, I usually have no idea as I'm just missing too much information. but saying bits are bits and saying a DAC cannot be impacted by a USB cable, those aren't the same claims. you sometimes getting an audible difference from a cable isn't evidence that the bits are corrupted and need saving or that digital audio is a failure. and of course if they did, the usb cable is probably not the first place I would look.

then obviously there is the issue that I won't trust anything from a guy on the internet making empty claims based on the anecdotal experience of a sighted test. there are 4 legit distinct reasons why I shouldn't trust anything he'll say just in that last sentence. those who wish to elevate the debate and try to show at least evidence that they really are experiencing something significant, will always be welcome by me(I can't talk for others ^_^). and once something is known to happen, has been double checked, has been shown to be repeatable, I will accept this simple new idea in my mind that changes everything: "it exists".
until then, I keep buying 5 cheap USB cables at a time, I measure them, throw away the lemons if I get some and that's about it. I do not understand why a USB cable would cost hundreds of dollars. and do not understand which electrical spec in the USB standard would require more than a few bucks to implement. let's add a few more for a tiny bit of quality control, a few more for a guy who knows how to solder, a little more for some fancy look and avoiding the worst plugs. let's say it's done by one single guy in a country with a lot of taxes and he doesn't sell that many, all in all I can't think of anything above 100/150$ that wouldn't be fantastic margins for no reason. and reading some stats on the audio market only seems to confirm that doubt.


----------



## theorist

JJF_888 said:


> What can you attest to as the reason for the sound differences in the cable then? That is what is of interest to many of us here as the audio world is, in many many ways, a DYI paradise/hell.



And of interest to me as well. As I have stated before on this topic thread, years ago I was into building audio kit following what were essentially, for its day, cutting edge research articles in a long gone mag called _The Audio Amateur_, about the impact to musical sound reproduction made by different types of capacitors, resistors, circuits, power supplies, etc comprising the musical reproduction system and that that kind of thing, all to do with analogue sound as digital sound did not exist in those days. Yet if you take on board that the digital noise that I am talking about is largely parasitical noise (emf noise etc) travelling from the data source of the computer/server in an analogue wave like manner, along with the bits and spaces of the digital signal, then a lot of this analogue theory to do with the effects of dielectrics, metal purity (six 9s copper, etc) and crystalisation, boundary joints (wire to plug to socket and so on joints), not to mention any interaction between the emf and the digital signal itself, all may have an effect on both the cable and the circuity at both ends that it is attached to. But again, as pointed out by Castlefargh, undoubtedly correctly, I am probably talking at the edge of my limits of knowledge here.



castleofargh said:


> . and emotions are bad at putting things into perspective. they often up like that, with 2 people thinking just as strongly about 2 things magnitudes apart in reality.



I agree, and also we are often talking about actually different things when we think think we are talking about the same thing. Indeed, short of audible musical drop-outs, the transfer/copying of digital musical files must be pretty near bit perfect, its only when we try and reconstruct these files into musical sounds in a HP or other musical system when the issues of imperfection tend to crop up, at least for some of us,  and I think some of the argues in this thread really come down to this difference. Further, while we might agree to differ in the value of an audiofile USB cable, I consider your points reasonable, well balanced and well made.


----------



## Currawong

gregorio said:


> how is that worse than espousing completely made up "facts" and/or "facts" with no reliable evidence whatsoever



Because being rude isn't providing reliable evidence or facts either, but reducing the discussion into a childish battle of egos.


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## castleofargh

theorist said:


> I agree, and also we are often talking about actually different things when we think think we are talking about the same thing. Indeed, short of audible musical drop-outs, the transfer/copying of digital musical files must be pretty near bit perfect, its only when we try and reconstruct these files into musical sounds in a HP or other musical system when the issues of imperfection tend to crop up, at least for some of us,  and I think some of the argues in this thread really come down to this difference. Further, while we might agree to differ in the value of an audiofile USB cable, I consider your points reasonable, well balanced and well made.


 reasonable and well made points aren't usually how people would define my posts.   I don't know if I would say that myself about this one, but you have no idea how nice it is to read. even more so from the one person who was most likely to be personally offended and go ballistic on me. thank you for that and for being able to stay fresh and cool. also something I'm not really good at.


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## Leo-

I didn't take the time to read all the posts in the thread, but here are my two cents

1. Chokes may affect the performance of USB. The maximum frequency of USB 2.0 is in the order of 100 MHz, and ferrites are quite effective in the MHz range. Therefore they may affect signal integrity. That's probably why you don't see ferrites in good audio USB cables. 

2. I just switched a (temporary) generic 3.5m USB cable for a good cable made by the Lampizator guys. The cable doesn't carry the 5V signal. Even though my player is an UltraRendu powered by a LPS-1, which I believed would be quite effective in blocking feeding rubbish to the USB cable, the difference was remarkable. All the things I didn't like in the system when I upgraded from a PC to the Rendu were gone when I switched the cable. Now I'm quite keen to figure out why the difference.


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## Duy Le (Sep 8, 2017)

Cartma said:


> I tried the WireWorld Ultraviolet 7 which had a separate isolated power line, didn't hear much of an improvement. There's something about Nordost's approach that make it ideal as a USB cable.


I am very happy with my Wireworld Starlight 7, it is more details than Supra but less bright than Chord Silver Plus. To my ears, the Chord Silver Plus lost something in bass and low-mid too.


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## chef8489 (Sep 8, 2017)

Duy Le said:


> I am very happy with my Wireworld Starlight 7, it is more details than Supra but less bright than Chord Silver Plus. To my ears, the Chord Silver Plus lost something in bass and low-mid too.


This is is completely absured.


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## gregorio (Sep 8, 2017)

theorist said:


> [1] And of interest to me as well.
> [2] Yet if you take on board that the digital noise that I am talking about is largely parasitical noise (emf noise etc) travelling from the data source of the computer/server in an analogue wave like manner, along with the bits and spaces of the digital signal, then a lot of this analogue theory to do with the effects of dielectrics, metal purity (six 9s copper, etc) and crystalisation, boundary joints (wire to plug to socket and so on joints), not to mention any interaction between the emf and the digital signal itself, all may have an effect on both the cable and the circuity at both ends that it is attached to. But again, as pointed out by Castlefargh, undoubtedly correctly, I am probably talking at the edge of my limits of knowledge here.



1. Apparently not.. You've been given the reason and if it really were of interest to you, you'd at least bother to go and research it or ask some questions about it but no, you've dismissed it as the explanation, even though you don't know much about it, simply because you don't like the idea of it. What you're really interested in is an explanation which doesn't challenge your belief that your perception is infallible. The problem is, that there is NO other logical/rational explanation. Excluding faulty equipment, every other explanation is ultimately based on audiophile USB cables having magical/irrational properties.

2. This has already been mentioned, several times: You explain clearly, you are applying "analogue theory" to digital audio and you can't, as digital audio was specifically invented to avoid analogue theory (it's limitations and susceptibility to noise)! You admit that you're "at the edge of your limits of knowledge" but neither that fact, nor the science, maths and most demonstrated of facts, seem to deter you from conflating analogue and digital theory/practise and steadfastly defending that position apparently unquestioningly. Why? Are you really so invested in your belief that your ears can't be fooled, that any explanation, no matter how ridiculous or how contrary to all the facts, is not just acceptable but preferable?

G


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## Leo-

I must have missed this class on Engineerings school where we were shown the crystalline structure of digital copper compared to the analogue one. In the microscope the looked very similar to my eyes, but perhaps there _is_ a difference?


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## theorist

Leo- said:


> I must have missed this class on Engineerings school where we were shown the crystalline structure of digital copper compared to the analogue one. In the microscope the looked very similar to my eyes, but perhaps there _is_ a difference?



Unfortunately, some people have a faith in what the believe in and nothing will challenge it. All we can do in this regard is to bless them and carry on trying to figure out why we hear (repeatably) what we do hear.


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## gregorio

theorist said:


> Unfortunately, some people have a faith in what the believe in and nothing will challenge it.



True ... It comes down to what you believe in, do you believe the proven maths, the science and the facts which are demonstrated trillions of times a second across the globe or do you dismiss all of that and instead believe what is provably flawed human hearing perception? You therefore need to bless yourself, presumably while you're trying to figure out something which has already been figured out!

G


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## Currawong

gregorio said:


> Excluding faulty equipment, every other explanation is ultimately based on audiophile USB cables having magical/irrational properties.



Then almost every DAC with USB made since the very first is faulty, by your logic.


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## Brooko

Oh come on Amos.  I've been silently following this thread, and even I'm finding it really hard to take the "blind faith" (nah, nah, nah fingers in my ears, I can't hear you talking logic, I (think) I hear it so it must be right) vs the well this is how digital audio really works approach.

The problem here is that you have people who think they hear something, and automatically attribute it to a cable.  Whether they actually hear it, or whether it is expectation bias or something else - we cannot ascertain because this is the DBT free part of the forum.  Which makes it frustrating because if people really want knowledge, then the actual tests are pretty easy to set up and run.  But we can't do that because of the location in the forum.

For those who've been following this debate (and I hope Greg is Ok with me disclosing this), he is an audio engineer, and producer.  He knows more about both digital and analogue audio than most of us will ever know or comprehend. And I understand his frustration.  Broken it down to its simplest state - the USB cable takes an electrical signal to DAC.  The signal contains the information in binary form - ie it is digital data in 1 or 0.  When it gets to the DAC (ie past the USB connection) it is decoded to an analogue signal. If the signal is being sent without compromise (and you'd have to be pretty incompetent to build a USB cable in today's age which does not meet the correct USB standard), then the signal arrives correctly.

If you have noise or degradation or timing issues, it (correct me if I'm wrong please Greg) is going to result in pops, dropouts, and jitter.  We already know that for most competently made devices, jitter is no longer an issue, and is basically inaudible on modern systems (check out Ethan Winer's audio myth series of videos where he intentionally introduces jitter, and at what level it is actually audible).  The talk of USB cables increasing sound-stage (really - it's going to change your transducers or the way the recording was miked??) or warmth, bass, treble (so frequency response?) is actually ridiculous.  And it doesn't matter how much you believe in it - it physically can't happen.  That's what the objection is.

Unfortunately in this part of the forum - we'll never discover truth, and I really would invite people to take a good look at my sig line - I think it is apt here:
_“Sometimes, the truths are those things you want to hear, and sometimes what we call truths are habitual lies we're comfortable with.”_

I'll close with this bit of advice.
Greg - you are in a section of the forum which (sadly) will not allow both sides of the debate to be properly explored.  Because of this, you're recent posts are starting to become aggressive, and it might be time to exit this discussion.  In the end, it would be you who would be ejected from the discussion - regardless of the fallacy of the approach of the opposing side.

To the rest of you - if you are really serious about discovering truth with your systems, and open to the possibility of proper tests - why not take the chance and discuss with open intent in the Sound Science section.  If someone does create a thread for this to be explored properly, I'm more than happy to come moderate it - and make sure neither side gets to ebullient.  That means I'd make sure the "objectivists" respect your experience as long as you respect their right to challenge the "why". I'm all in favour of real discussion and real discovery of "why".  You can't do that to its fullest extend in this forum section. If someone does this (sets up a new thread) - send me a link.


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## chef8489 (Sep 8, 2017)

Brooko said:


> Oh come on Amos.  I've been silently following this thread, and even I'm finding it really hard to take the "blind faith" (nah, nah, nah fingers in my ears, I can't hear you talking logic, I (think) I hear it so it must be right) vs the well this is how digital audio really works approach.
> 
> The problem here is that you have people who think they hear something, and automatically attribute it to a cable.  Whether they actually hear it, or whether it is expectation bias or something else - we cannot ascertain because this is the DBT free part of the forum.  Which makes it frustrating because if people really want knowledge, then the actual tests are pretty easy to set up and run.  But we can't do that because of the location in the forum.
> 
> ...


Thank you. I am all for proper tests.


----------



## Brooko

And for anyone who thinks there can never be a difference (because objectivists can do the nah, nah, nah I'm not listening thing too) - this article is pretty good.
http://archimago.blogspot.co.nz/2014/01/demo-measurements-what-does-bad-usb-or.html

He touches on what (in the past) could have an affect - and how it would degrade the sound (cut-outs, pops, errors).  Notice his comments regarding tonal changes and soundstage.


----------



## gregorio

Brooko said:


> [1] For those who've been following this debate (and I hope Greg is Ok with me disclosing this), he is an audio engineer, and producer.
> [2] If you have noise or degradation or timing issues, it (correct me if I'm wrong please Greg) is going to result in pops, dropouts, and jitter.
> [3] ... you're recent posts are starting to become aggressive, and it might be time to exit this discussion.  In the end, it would be you who would be ejected from the discussion - regardless of the fallacy of the approach of the opposing side.



1. Yep, that's OK.
2. That's correct, as far as the digital data itself is concerned. There have been some DACs which have/had issues with improper isolation of the power supplied by the USB spec, which could introduce noise in the analogue side of the DAC and which in theory could be cured by a custom USB cable doing the isolation job that the DAC itself should be doing..I say in theory simply because I haven't investigated this specific issue in any detail.
3. It certainly getting to the stage where I've already stated the pertinent facts and logic and all that's left is expressing frustration that those facts can't apparently be comprehended (or are deliberately being misrepresented) and therefore as you advise, I'm just about at the point when I should exit the discussion.



Currawong said:


> Then almost every DAC with USB made since the very first is faulty, by your logic.



No, you've missed the context of the previous sentences to the one you quoted. It's every explanation other than faulty equipment and/or human hearing perception. Even if it were the case that "by my logic" all USB DACs must be faulty, I still don't understand why you chose to pull me up on that but not theorist, whose logic, that digital data transfer can never be perfect, would mean that all digital devices (not just USB DACs) must be faulty.

G


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## Clive101

Brooko said:


> For those who've been following this debate (and I hope Greg is Ok with me disclosing this), he is an audio engineer, and producer. He knows more about both digital and analogue audio than most of us will ever know or comprehend. And I understand his frustration. Broken it down to its simplest state - the USB cable takes an electrical signal to DAC. The signal contains the information in binary form - ie it is digital data in 1 or 0. When it gets to the DAC (ie past the USB connection) it is decoded to an analogue signal. If the signal is being sent without compromise (and you'd have to be pretty incompetent to build a USB cable in today's age which does not meet the correct USB standard), then the signal arrives correctly.
> 
> If you have noise or degradation or timing issues, it (correct me if I'm wrong please Greg) is going to result in pops, dropouts, and jitter. We already know that for most competently made devices, jitter is no longer an issue, and is basically inaudible on modern systems (check out Ethan Winer's audio myth series of videos where he intentionally introduces jitter, and at what level it is actually audible). The talk of USB cables increasing sound-stage (really - it's going to change your transducers or the way the recording was miked??) or warmth, bass, treble (so frequency response?) is actually ridiculous. And it doesn't matter how much you believe in it - it physically can't happen. That's what the objection is.



I think you have nailed this.

I have no idea why different USB cables sound different to me ( some sound the same others do not ), I am sane and keep an open mind and prefer a normal cable for cost effect reasons unless my brain as suggested is playing tricks on me..?

For others the sound of a USB cable make no difference as all they only carry zeros and ones to the DAC.

Unless people try to understand there could be a difference no one will be able to find why they sound different only to some people...?

Perhaps the new thread should be "Why do some people hear a difference in USB cables" ..?


----------



## Brooko

Like I said - create a thread in SS, PM me the link, and I'll make sure both sides behave themselves so we can actually make progress on finding the why


----------



## castleofargh

one person with those clear differences could very much decide to conduct a few tests objectively, and maybe learn a thing or two about his own specific situation. for general answers here or in the sound science section, there will always be the issue of sample size.


----------



## theorist

Brooko said:


> 1) The talk of USB cables increasing sound-stage (really - it's going to change your transducers or the way the recording was miked??) or warmth, bass, treble (so frequency response?) is actually ridiculous.  And it doesn't matter how much you believe in it - it physically can't happen.  That's what the objection is.
> 
> 2) Unfortunately in this part of the forum - we'll never discover truth, and I really would invite people to take a good look at my sig line - I think it is apt here:
> _“Sometimes, the truths are those things you want to hear, and sometimes what we call truths are habitual lies we're comfortable with.”_
> .



1) I have never had an USB cable effect perceived soundstage or frequency response. What I hear is in differences in 'palpability', for lack of a better term, more solidity in the presence of the music, ie more there there. A printer or freebee USB cable generally has a lack of substance in the music being-there compared to a better sounding cable. Whereas a better USB cable, at least for me,  presents the music with better solidity, timing and space around the notes, hence its more palpable. 

Sometimes in comparing USB cables this increase in 'realness' jumps out immediately on hearing it with one cable over another, other times the difference is much less apparent and it takes considerable time and reflection to work out the difference between them, but there is always some variation between different USB cables to my ears, or at least my mind. But if this is expectation bias, why then when asked to beta test two Tellurium Q USB cables (that looked identical and were not for sale), the first sent me I considered rather less than great and the second I perceived sounded great -- ie really palpable sounding music -- from the first moment I heard it, and I understand that this later version is now the one in production?


2) So true!


----------



## Brooko

Did you test the two cables side-by-side, ensuring the output was completely volume matched, and completely blind - so all you are judging is on sonics.  And this means multiple times with no uniformity in which cable being presented so you actually have no visual or other cues?  Because without that - you can't say they sound different. People always say they trust their ears.  Its the filter their brain puts over everything that I don't trust.



> Sometimes in comparing USB cables this increase in 'realness' jumps out immediately on hearing it with one cable over another, other times the difference is much less apparent and it takes considerable time and reflection to work out the difference between them, but there is always some variation between different USB cables to my ears, *or at least my mind.*



Its the second part (I highlighted) that is the telling part.  That's what you need to establish because the mind is a hugely powerful influence.

At the end of the day - when I'm using my iDSD on my system at home, I upscale to DSD playing from my computer - and a little blue light comes on the unit.  Here's the kicker - I know with the same recording, same master, volume matched, and transcoded to : DSD, 24/192, 24/96, redbook, and aac256 (lossy) - if I've done the transcode right, I can't tell a difference in a proper volume matched double blind test.  I've done the tests - and I really can't tell the apart.  I know of no-one who has performed a proper test that can either.  But it doesn't stop my brain telling me that upscaling sounds better.  And if you took that blue light away I would never know.

So at home, I upscale, and it makes me happier.  But I don't make claims about one sounding better - because I know that it can't (and indeed it doesn't).  It doesn't make me a poor listener, it doesn't make me a snake-oil believer.  it just proves I'm human.  What I'd love to see is more of the myth and mystery removed.  If we can actually know where our own limits are, then we can at least understand some of the claims properly.  I'm all for enlightenment.


----------



## Currawong

Brooko said:


> If you have noise or degradation or timing issues, it (correct me if I'm wrong please Greg) is going to result in pops, dropouts, and jitter.



If the level of noise is significant enough to distort the digital waveform only (see here: http://lampizator.eu/LAMPIZATOR/TRANSPORT/CD_transport_DIY.html). The noise that is of concern is at a level low enough not to affect the digital signal, but high enough to affect the analog components. The main issue there in isolating that noise related, on the one hand, to the availability of components (ie: transformers, chips) that could isolate noise from a USB source while still allowing full USB 2.0 speeds (Schiit found that network isolation transformers work well for that) and on the other hand, removing noise generated by the USB components themselves.



gregorio said:


> I still don't understand why you chose to pull me up on that but not theorist,



You "pulled up" theorist very well, and for the most part, I agree with your responses to him. I don't need to duplicate that. Going by my own experiences, I don't believe that he may not have experienced a difference between USB cables, but what he attributes that to is wrong to me as well. The difference is that I know of perfectly reasonable, technically sound reasons why he (and other people) may have experienced what they have. 

The two main problems I see here are, respectively:

1. Someone believes they have a difference swapping a cable. Instead of asking _"Why is this happening? What don't I understand about electronics that would be useful that I could improve my system without expensive and unnecessary trial and error?"_ they may end up arguing with incorrect assumptions as theorist did.
2. Someone else believes that the first person's experiences are BS, but instead of asking _"Why are they experiencing this? What could be a possible technical explanation if what they are experiencing is genuine?"_ they end up arguing from the point of view of their limited knowledge. 

The irony is, I now know two companies who, respectively, solved pretty much all analog and digital cable issues using basic electrical knowledge. One I've already mentioned.


----------



## gregorio

Currawong said:


> 2. Someone else believes that the first person's experiences are BS, but instead of asking _"Why are they experiencing this? What could be a possible technical explanation if what they are experiencing is genuine?"_ they end up arguing from the point of view of their limited knowledge.
> [3] The irony is, I now know two companies who, respectively, solved pretty much all analog and digital cable issues using basic electrical knowledge.



Firstly, I do not believe that theorist's experiences are BS! I do not dismiss his experiences, just his explanation of them. There are two possibilities:
1. He has a faulty DAC, although it's hard to see how a so called audiophile grade USB cable would make any difference as far as the data is concerned.
2. There are some biases and/or other issues of perception at play. I realise that for many audiophiles even the suggestion of such a thing appears to be some sort of heinous insult. Not for me though, in fact if anything, the exact opposite. If it weren't for the biases and issues of human hearing perception, it would be impossible to appreciate music, films and TV and, my job and the many thousands of others who work in my field, effectively depends entirely on my understanding of how trick and manipulate this biased perception.
3. Even more ironical as far as I'm concerned! I'm sure many here, maybe even the majority have more experience of audiophile equipment than me. I do and have owned some pieces (transducers mainly) of what would probably be described as mid-level audiophile equipment and I have heard some of the ridiculous priced audiophile stuff. However, I worked extensively with high-end pro audio equipment and on many occasions with equipment at the lower end of the pro-audio scale. I've used relatively cheap USB audio interfaces over the course of the last 15 years or so from EMU, RME, Focusrite, Prosonus, Digidesign, Yamaha and various others and here's the thing: We're talking typically about 16 x 16 ins/outs which in normal usage ends up being about 8-10 times more USB 2 data per second than an audiophile stereo DAC ever has to cope with and they do it typically for 50 or so hours a week, week in, week out, flawlessly. Last year I was working with a USB unit (Antelope, if I remember correctly) running simultaneously 30 inputs, a main mix out and two different stereo cue mix outs all at 24/96 over a rather decrepit looking old no brand USB2 cable, no data corruption in the double session and impressively clean/quiet.
I don't know how many audiophile USB DACs have issues with power isolation/noise but why are there any? The pro audio market apparently has been employing the appropriate "basic electrical knowledge" for years, has far more demanding data handling requirements, power and noisy (EM/RF) environments to deal with than anything the audiophile market faces and yet apparently some/many audiophile DAC manufacturers don't have or don't apply the appropriate "basic electrical knowledge" even though they're typically charging way more. The solution should be for more audiophile DAC manufacturers to drop some of the silly "audiophile" specs/formats and put a bit more effort into "basic electrical knowledge" but why bother when instead, you can sell them even more rubbish at inflated prices to cure the problems which the DACs should never have been released with in the first place! If a USB DAC manufacturer also sells a USB recleaner/filter/purifier which supposedly improves the SQ then why on earth didn't they put that circuitry in their DAC in the first place? The answer is that many audiophiles will fall for it and better still, not feel duped and complain but do and feel the exact opposite?! I can't recall ever seeing a USB cable in a pro studio which cost more than about 20 bucks or so and even mentioning audiophile or audiophile equipment is likely to be met with open ridicule.

G


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## theorist

Brooko said:


> Did you test the two cables side-by-side, ensuring the output was completely volume matched, and completely blind - so all you are judging is on sonics.  And this means multiple times with no uniformity in which cable being presented so you actually have no visual or other cues?  Because without that - you can't say they sound different.



I did not have the two beta samples at the same time (which became the Tellurium Q Silver), but I compared them with my then system USB cable. My then system USB cable was a Tellurium Q Black Diamond. Obviously, I was aware of what cable was in the system, since I had to swap them. They were swapped numerous times with my amp mute button pressed on, so at least at first listen (mute off) they would have had a completely matched volume (as far as I am aware a USB cable can have no effect on system gain). If I had any initial expectation bias it would be that the first tested beta would sound better than my Black Diamond cable, but it very clearly did not. I then rather grudgingly tried the second cable a few weeks later, with a clear in my mind expectation bias that I wasting my time with all this about-to-do cable swapping, as the new beta would probably be not a lot better than the first, and I really just wanted to listen to my music, but I felt obliged to do so. After sitting on the second beta for a number of days I finally swapped it into my system and was immediately impressed by the increased musicality/liveliness  that I heard in my system, swapped it out, this went away, swapped back -- there it was. So not a blind test, but for me it was rather conclusive.



gregorio said:


> Firstly, I do not believe that theorist's experiences are BS! I do not dismiss his experiences, just his explanation of them.



Thank you G for that. But could not a third explanation not be there. I have a very simple, but pretty good HP digital audiophile system on a dedicated power supply separate from the rest of the household attached to pretty clean mains power. The system is star earthed wired and grounded (2 metres directly below the system with a two metre earth rod) and the power and analogue cables are all high quality. In other words the system is well sorted and very clean, ie the noise floor is very low. Compare this to your "far more demanding data handling requirements, power and noisy (EM/RF) environments to deal with than anything the audiophile market faces". Between yourself, Shannon (1948) and others I now except that the transcription of digital files, short of drop-outs, must be near perfect  with any properly made USB cable -- thank you for that, again, since I said this before -- but this does not mean that the reproduction of music from these files will be perfectly reproduced (just think of the unnatural sounding pre-ringing induced by the digital filters in most DAC/ADCs -- what MQA is trying to fix) and here everything in the system may have an impact on this replication from the data file of the musical sound. Could not this also include USB cables, at least at very low levels and not directly related to the digital file transcription itself (ie EM/RF noise that has little or no impact on the digital data transcription itself, but does have an impact on the DAC circuit, even one that is properly designed to spec)? I would happily like to blind test this, but in a system with the attention to detail similar to my system, and see if the listeners can tell the differences, or not, between USB cables.


----------



## Brooko

theorist said:


> I did not have the two beta samples at the same time (which became the Tellurium Q Silver), but I compared them with my then system USB cable. My then system USB cable was a Tellurium Q Black Diamond. Obviously, I was aware of what cable was in the system, since I had to swap them. They were swapped numerous times with my amp mute button pressed on, so at least at first listen (mute off) they would have had a completely matched volume (as far as I am aware a USB cable can have no effect on system gain). If I had any initial expectation bias it would be that the first tested beta would sound better than my Black Diamond cable, but it very clearly did not. I then rather grudgingly tried the second cable a few weeks later, with a clear in my mind expectation bias that I wasting my time with all this about-to-do cable swapping, as the new beta would probably be not a lot better than the first, and I really just wanted to listen to my music, but I felt obliged to do so. After sitting on the second beta for a number of days I finally swapped it into my system and was immediately impressed by the increased musicality/liveliness  that I heard in my system, swapped it out, this went away, swapped back -- there it was. So not a blind test, but for me it was rather conclusive.



So not tested side-by-side, you knew which cable was which, and you formed an opinion based on auditory memory - which we know is extremely fleeting (more than a few seconds is simply not reliable).  I'm not discounting what you think you heard - as I'm sure you believe there is a difference (and that is the filter our brain can put on for us).  Talk to audio engineers or producers, and I'll guarantee that practically everyone will have an example of EQing a mix, spending hours getting it just right, and then finding that the EQ was never engaged at the time.  You convince yourself that you hear a difference so you do.  I've done it myself.  Unfortunately, the only way to get a more valid test as to what is really happening in your case is direct comparison.  I do not doubt for a minute that your experience of the perceived change is valid.  What I doubt is whether it is actually real (the change), or audible.


----------



## gregorio

theorist said:


> [1] But could not a third explanation not be there.
> [2] In other words the system is well sorted and very clean, ie the noise floor is very low. Compare this to your "far more demanding data handling requirements, power and noisy (EM/RF) environments to deal with than anything the audiophile market faces". ...
> [3] .. (just think of the unnatural sounding pre-ringing induced by the digital filters in most DAC/ADCs -- what MQA is trying to fix)
> [4] Could not this also include USB cables, at least at very low levels and not directly related to the digital file transcription itself (ie EM/RF noise that has little or no impact on the digital data transcription itself, but does have an impact on the DAC circuit, even one that is properly designed to spec)?



1. Not really, I'll explain why:
2. Typically, commercial studios have a "machine room". The computers, power amps, ADC/DACs and stacks of other electronics are put in this room and they're noisy rooms. However, the control rooms are sonically isolated from the machine room and additionally have been constructed and acoustically treated for the purpose. So while pro ADC/DACs often have to operate in a noisy environment, it's extremely unlikely your listening environment has a lower noise floor than a good commercial recording studio control room, unless you've spent very serious amounts on isolation/acoustics.
3. That's another whole audiophile myth/marketing opportunity! Again, the science forum might be the better place for that discussion but essentially, no. Pre or post ringing digital artefacts of digital filters are completely inaudible. Like jitter, it was a bit of an issue in the early days of digital but not for many years. Having said this, there are some devices with audible filters, the Pono is an example I have experienced but audible filters is either due to incompetent filter design or a deliberate design choice not to aim for a linear response/high fidelity (as is the case with the Pono). Incompetent filter design comes under the the "faulty" category, as even extremely cheap DACs manage very competent digital filter designs (those found inside an iPhone for example).
4. Yes, it could and I've seen evidence of audiophile DACs being affected by EM/RF noise, just from being placed near a laptop. Again though, this comes under the first explanation, it's an incompetent, faulty design! In addition to my high-end pro ADC/DACs I've got a little USB 2x2 ADC/DAC. It sits about 1ft from a 12 core workstation, about 3ft from a 10 disk NAS, about 8ft from a powerful wireless router and the small room it's in has loads of other equipment which uses in total over 4kW. It cost about $90, uses a 3ft Amazon Basics USB 2 cable and is impressively unaffected by it all, as are the other pro USB ADC/DACs I've used and of course my high-end ADC/DACs are unaffected (but they're not USB).

G


----------



## theorist

Brooko said:


> So not tested side-by-side, you knew which cable was which, and you formed an opinion based on auditory memory - which we know is extremely fleeting (more than a few seconds is simply not reliable).  I'm not discounting what you think you heard - as I'm sure you believe there is a difference (and that is the filter our brain can put on for us).  Talk to audio engineers or producers, and I'll guarantee that practically everyone will have an example of EQing a mix, spending hours getting it just right, and then finding that the EQ was never engaged at the time.  You convince yourself that you hear a difference so you do.  I've done it myself.  Unfortunately, the only way to get a more valid test as to what is really happening in your case is direct comparison.  I do not doubt for a minute that your experience of the perceived change is valid.  What I doubt is whether it is actually real (the change), or audible.



While I agree that blind or preferably double-blind testing will certainly remove any potential for self-delusion and provide a 'scientific' certainty of perception if repeated sufficiently by enough cases for statistical validity, I'm not sure that I can pragmatically buy into constantly using this high standard of testing for my personal hobby choices, even if this lack of blind testing may be at times lead to incorrect perceptions.


----------



## theorist

gregorio said:


> 1. Not really, I'll explain why:
> 1. unless you've spent very serious amounts on isolation/acoustics.
> 2. That's another whole audiophile myth/marketing opportunity!



1) I just listen with HPs, I have no room speakers and was referring to system, not acoustical,  noise floor.

2) I would actually like to hear your take on MQA then if you don't buy into its claims about taking ADC/DAC distortions out of the data signal recording/playback chain.


----------



## Brooko

theorist said:


> While I agree that blind or preferably double-blind testing will certainly remove any potential for self-delusion and provide a 'scientific' certainty of perception if repeated sufficiently by enough cases for statistical validity, I'm not sure that I can pragmatically buy into constantly using this high standard of testing for my personal hobby choices, even if this lack of blind testing may be at times lead to incorrect perceptions.



No problems with that approach either. Sometimes people are happy with what they don't know - and that's a completely valid choice   You'll get one guy who simply likes tube amps, and 2nd guy who likes the sound, but recognises the added 2nd order harmonic distortion is what is colouring the sound, and knows that is why he likes it. Both are valid observations.

I'd love for you to be able to take that test someday though.  It wasn't until I started taking the time to test myself on a lot of pre-held beliefs that I started realising how much I had to learn.

Enjoy the music


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## gregorio (Sep 11, 2017)

theorist said:


> 1) I just listen with HPs, I have no room speakers and was referring to system, not acoustical,  noise floor.
> 2) I would actually like to hear your take on MQA then if you don't buy into its claims about taking ADC/DAC distortions out of the data signal recording/playback chain.



1. HP's will typically reduce the the acoustical noise floor by about 10-15dB, sealed IEMs by as much as about 30dB. A typical commercial studio will have an acoustic noise floor roughly 10-20dB lower than a typical home listening environment. Therefore there is a very rough equivalence (as far as the noise floor is concerned) between listening at home on headphones and listening on speakers in a commercial studio. However, although virtually all commercial music releases are mixed and mastered on speakers, those mixes and masters are typically checked/referenced on HP's in the studio. I have a set of Senn HD650's just for this purpose. All this is relevant because as far as modern digital audio is concerned, the limiting factor is the acoustical noise floor, not the digital noise floor,which is many times (as much as 1,000 times) lower than the acoustic noise floor! The analogue side of a digital system is far noisier than the digital side, transducers in general and speakers in particular, but most good quality DACs advertise a noise floor anywhere from about -110dB to as low as about -125dB in a few cases. To be able to hear that DACs noise floor above or at the same level as the acoustic noise floor of your listening environment (even wearing cans rather then listening on speakers) would mean playback levels at or well beyond the pain threshold, levels roughly 10-100 times higher than anyone would choose to listen. If you can hear the noise floor of your DAC without turning the volume up to ear splitting levels then your DAC is seriously flawed.

2. MQA are making a number of claims and backing most of them up with actual scientific data but with MQA it's often what they don't tell you which invalidates the claim. There are 4 main problems with this particular claim: 1. As already mentioned, except possibly in some early digital recordings, the ADC/DAC timing distortions MQA is trying to "fix" should be well beyond audibility to start with. 2. The timing distortions which do exist pale into utter insignificance compared to the other timing distortions in the chain, the application of EQ, compression and other effects during mixing and mastering and the timing errors inherent in microphone placement being obvious examples and there is no way to know what these timing distortions.were or correct for them. 3. Even when the original ADC is known (which may not be often) and even if MQA can compensate for it's timing distortion, that's still irrelevant in many/most cases! The recording and mixing workflow varies significantly, depending on both the music genre and when the recording/mixing occurred (and therefore the technology used). Up until about 10 years ago, there was not just a an ADC used during recording, there were also ADCs and DACs used in the mixing and mastering chain, typically multiple round trips through at least two different ADCs and DACs, possibly as many as a dozen or more times. This compounds the timing distortions (possibly to audible levels) but again there is no way to know how many round trips were made or even all the different ADCs and DACs employed on any particular mix/master. Any attempted compensation just for the recording ADC and consumer's DAC is just as likely to make matters worse rather than better. Even today, many mastering engineers will convert the mix to analogue to pass through some vintage analogue compressor or EQ and then convert back to digital again using a different ADC than the one used for recording. 4. If timing errors are audible the mix engineer and/or mastering engineer had the option of correcting them, often they don't because the result of those timing distortions may be preferable artistically. Obviously then, the last thing you want is a distribution format to come along and correct for something which has already been corrected or which the artistic decision has already been made not to correct. Having said this, a single pass through a recording ADC and then a consumer's DAC should not have any audible effect and therefore neither should any correction which MQA is applying.

G


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## gregorio

theorist said:


> While I agree that blind or preferably double-blind testing will certainly remove any potential for self-delusion and provide a 'scientific' certainty of perception if repeated sufficiently by enough cases for statistical validity, I'm not sure that I can pragmatically buy into constantly using this high standard of testing for my personal hobby choices, even if this lack of blind testing may be at times lead to incorrect perceptions.



1. Although the term "self-delusion" is probably technically accurate, it's negative association makes me uncomfortable. Without that "self-delusion" there would be no music in the first place, it would just sound like a sequence of unrelated noises with no emotional significance/impact, no associations with qualitative judgements and no meaning in general!

2. I don't think anyone is suggesting constantly using DBT to inform every decision. My advice would be to start slow and just use it for the more expensive and most contentious decisions. Audiophile USB cables can be expensive and are extremely contentious because only some in the audiophile community believe they make any difference and none (AFAIK) in the pro audio community. A good candidate for DBT if you're considering purchasing an audiophile USB cable. As I think Brooko mentioned, doing DBTs is very informative, sometimes surprisingly so. Over time you build up knowledge of your perception and can therefore better judge when a DBT would be appropriate. If you haven't already seen it, I recommend this short (3 min) video of the McGurk Effect, which is a bit of an eye opener if you're a perception doubter and leads to some interesting conclusions.

G


----------



## theorist

gregorio said:


> MQA are making a number of claims and backing most of them up with actual scientific data but with MQA it's often what they don't tell you which invalidates the claim...



Thanks for this info, its very useful to know, I had not thought about this from the mixing perspective, and I assume that this variation in ADCs and DACs use  must also vary to some degree between tracks due to differences in mixing for each track on many albums. It certainly does invalidate their claims!

Compression today really drives me spare, as while think I understand the commercial justifications for it: perceived louder is 'better', at least in the market, it so destroys the dynamics of the music. I was not aware of how bad this is until copying a hi res 24/176 copy of Shelby Lynne's "Just a little lovin' onto my DX and for some reason it dumped all the tracts side by side to a prior CD rip of the work -- easily enough fixed when I got around to it -- but in the interim I could both hear (and see the output visually in Roon's playback display) the profound difference in compression between the two copies of each track. With the CD rip loud but boringly dynamically flat (visually a flat solid band of output in the Roon display) and the hi res version so much more alive, dynamic and emotional, visually in the display (without the emotional bit!), as well as most importantly, sonically to my ears, especially once the volume was turned up to compensate for the lower output on the majority of quieter parts. If all hi res was this less compressed, compared to CDs, it would be worth replacing all my 1000s of CD rips for the better dynamics alone!


----------



## gregorio

theorist said:


> [1] I assume that this variation in ADCs and DACs use  must also vary to some degree between tracks due to differences in mixing for each track on many albums.
> [2] Compression today really drives me spare, as while think I understand the commercial justifications for it: perceived louder is 'better', at least in the market, it so destroys the dynamics of the music.
> [3] If all hi res was this less compressed, compared to CDs, it would be worth replacing all my 1000s of CD rips for the better dynamics alone!



1. Generally, though not always, the various ADC/DACs used on one track will be the same on all the tracks on the album but not the number of round trips through those ADC/DACs, which could vary wildly between the different tracks. All MQA attempts to "fix" is one pass through the recording ADC and the pass through the consumer's DAC. Note that this mainly affects recording older than about 5-10 years. Today the typical workflow is ITB (in the box), meaning one pass through the recording ADC and then all processing is carried out in the DAW (digital audio workstation) without any further D to A  or A to D conversions for analogue processing. This isn't always the case though.

2. This isn't quite as simple an issue as it appears. To try and simplify, there's two parts to it:
A. High levels of compression (destroyed dynamics) is actually "better" in many situations. Many consumers listen to music while doing other tasks in extremely noisy environments, such as when working, travelling, exercising, doing chores, etc. Wide dynamic range recordings are completely useless in these situations because the quieter parts will be beneath the noise floor of the listening environment and inaudible. For example, I don't listen to classical music when driving because I could be sitting there for minutes not hearing anything at all during the quiet passages in the music and I don't want to be turning up and down the volume all the time as the music gets quieter and louder. So I just listen to popular music genres which are heavily compressed when driving and at least I can hear it all. Listening critically though, for example when I'm at home doing nothing else but listening, on a decent system in a moderately quiet listening environment, then destroyed dynamics is very annoying or at least far less preferable than wider dynamics. So, there is a good justification for two masters, a highly compressed one and a far less compressed one or if only one master, for it to be highly compressed because music is consumed by far more people in noisy environments than there are audiophiles. 
B. Economics! The problem with the CD container format (16/44) is that it's been around for a long time. That's a very serious problem economically because once a consumer has bought a decent 16/44 DAC/DAP/system there's no real need to buy another one until it wears out, and this isn't just an equipment problem but also a problem for content owners (record labels) and distributors. That's why "high-res" consumer distribution formats were invented, you had to buy new equipment to play "hi-res" and obviously you have to buy the content/music again or buy new content in a more expensive "high-res" format. The reason I put "high-res" in quotes is because in practise it's NOT higher resolution, "high-res" results in EXACTLY the same resolution as 16/44 within the audible range. This inconvenient fact can be overcome for some consumers with marketing, however, that marketing is far easier and the number of potential consumers is far greater if there is a real audible difference. This brings us back to the point above and the justification for two masters, release the highly compressed one in 16/44 format and the less compressed one in high-res, now we have a real, measurable and audible difference between high-res and 16/44 and in critical listening situations the high-res version should always sound superior! Of course, because there is no resolution difference, they could release both versions in 16/44 and the less compressed version would be audibly indistinguishable from a "high-res" version but economically that doesn't serve any section of the industry's best interests.
3. As just explained, you buying your entire music collection again is one of the main reasons hi-res exists. Record labels have literally billions of dollars worth of back catalogue content and they want/need to make money from it. Sometimes it's not technically possible to create a far less compressed version for "high-res" release, in which case you either have to add even more compression and/or create a new (or existing master) which is different in some other respect. Therefore, you cannot guarantee that repurchasing your collection in "high-res" will always get you a less compressed version.

We may be in danger of getting kicked out! Although arguably obliquely related, what we're discussing now is pretty far off topic.

G


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## theorist

gregorio said:


> We may be in danger of getting kicked out! Although arguably obliquely related, what we're discussing now is pretty far off topic.
> 
> G



Yes, perhaps it is, but it is really useful information, so I am sure everyone will bear with us. Thanks for sharing this with us. 

Just to keep it on topic, while we may still disagree about the value of audiophile USB cables (perhaps I need my delusions), thanks for contributing to the topic string, I have learnt from your posts!

On another related note check out http://antipodesaudio.com/articles.html . I received this link in a marketing email this morning to spend money on upgrading my music server. Of specific interest to this topic string are two links on this page to: 'Of Faith & Science' and 'Design Approach' (I could not get direct links to each specific topic article, so have to include the full marketing pitch -- sorry). Yes, it is marketing bumph, but I think this string's readership may find these two specific articles interesting, either in agreeing with what is put forth by Mark or in knocking holes in what has been stated, as you think is appropriate.


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## Cartma (Sep 12, 2017)

You know, I'm starting to get annoyed with some of these post. I'll admit, I too was skeptical about USB cables but I figured I would try some for myself and see. I was given the opportunity to try some higher-end familiar cables for free before I decided to make a purchase.... This is something that some posters here need to do before you start claiming we are all delusional when you haven't even tried a higher end USB cable. If you have tried some and still think it's nonsense,  I will admit not all of the higher end cables necessary offer better performance, but some do, you have to be careful.

Why would I go out and spend hundreds of dollars on a USB cable that made no difference? I find this offensive.


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## theorist

Cartma said:


> You know, I'm starting to get annoyed with some of these post. I'll admit, I too was skeptical about USB cables but I figured I would try some for myself and see. I was given the opportunity to try some higher-end familiar cables for free before I decided to make a purchase.... This is something that some posters here need to do before you start claiming we are all delusional when you haven't even tried a higher end USB cable. If you have tried some and still think it's nonsense,  I will admit not all of the higher end cables necessary offer better performance, but some do, you have to be careful.
> 
> Why would I go out and spend hundreds of dollars on a USB cable that made no difference? I find this offensive.



Cartma: I don't disagree with you indeed my Nordost USB cable cost rather more than your Heimdall 2 (I only use Heimdall 2 HP cables in my system, as that is as far as Nordost goes in HP cables). However, others do disagree, as gregorio has stated in considerable detail in numerous posts, but, importantly, we have to respect each others perspective and here I was simply acknowledging his in stating "perhaps I need my delusions" [which are that good USB cables do make an important difference].


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## Arpiben

Cartma said:


> *Why would I go out and spend hundreds of dollars on a USB cable that made no difference? I find this offensive*.



Why would I bet or spend hundreds of dollars on a USB cable in order to hope correcting:

source (DAP) impedance or any other deficiencies
load (DAC) impedance or any other deficiencies
source + load interoperability issues
etc...
A USB cable is a simple transmission line with dedicated specifications.Nothing more.
Are you buying 500 USD AC power cords in order to improve AC filtering?

Please do not take offense.
My approach is kind of like a doctor trying to find the proper cure.
Your approach is kind of not believing/knowing about possible cures and applying paralel ways.
We are free, both of us, to apply whatever medecine we feel like.


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## chef8489 (Sep 12, 2017)

Cartma said:


> You know, I'm starting to get annoyed with some of these post. I'll admit, I too was skeptical about USB cables but I figured I would try some for myself and see. I was given the opportunity to try some higher-end familiar cables for free before I decided to make a purchase.... This is something that some posters here need to do before you start claiming we are all delusional when you haven't even tried a higher end USB cable. If you have tried some and still think it's nonsense,  I will admit not all of the higher end cables necessary offer better performance, but some do, you have to be careful.
> 
> Why would I go out and spend hundreds of dollars on a USB cable that made no difference? I find this offensive.


1 there is a problem with the cable you are currently using and a proper in spec cable will work you just did not notice till you changed cables
2 there is a problem with your dac or source and you are trying to remedy it with an expensive cable instead of fixing it with the source or dac
3 you paid a lot of money and there really is no difference and would not notice a difference in a proper blind test or double blind test. It is all placebo.

And yes I have tried many expensive cables into the thousands of dollars. so your point is moot about me not trying them.


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## gregorio

Cartma said:


> You know, I'm starting to get annoyed with some of these post. .... Why would I go out and spend hundreds of dollars on a USB cable that made no difference? I find this offensive.



If you are referring to my posts then I don't understand what you are getting annoyed about because I am NOT saying that you (or anyone else) who hears a difference between USB cables is lying and not hearing a difference. What I am saying is that there are three fundamental steps to hearing. 1. The sound which enters your ears. 2. The information your ears then send to your brain and 3. How your brain then interprets that information. Unless (potentially) you have a faulty/broken/flawed DAC or are comparing against a faulty/broken USB cable, the differences you ARE hearing are occurring entirely in step #3 (there is no difference in step #1, the sound entering your ears).

G


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## Cartma

All USB cables I tried had their own sound signature as well as a sound signature that match their same line of cables. Same type of situation as digital coax cables carrying the same signature as the same line's power cables and interconnects. I think it's more than just doing it right or doing it wrong.


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## chef8489

Cartma said:


> All USB cables I tried had their own sound signature as well as a sound signature that match their same line of cables. Same type of situation as digital coax cables carrying the same signature as the same line's power cables and interconnects. I think it's more than just doing it right or doing it wrong.


A usb cable has no sound signature at all.


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## gregorio

theorist said:


> On another related note check out http://antipodesaudio.com/articles.html . I received this link in a marketing email this morning to spend money on upgrading my music server. Of specific interest to this topic string are two links on this page to: 'Of Faith & Science' and 'Design Approach' (I could not get direct links to each specific topic article, so have to include the full marketing pitch -- sorry). Yes, it is marketing bumph, but I think this string's readership may find these two specific articles interesting, either in agreeing with what is put forth by Mark or in knocking holes in what has been stated, as you think is appropriate.



Yep, I've seen this sort of thing numerous times before. It's nonsense but potentially it's not only nonsense, potentially it's very good marketing and it's very good marketing because it sounds entirely reasonable. In fact, to some/many who believe they hear differences, it probably sounds far more reasonable than the actual facts! However, with some basic factual knowledge and the application of some logic, it's really not very difficult to see that it's just nonsense. The author hopes that the reader either doesn't have that basic knowledge, isn't capable of simple logic or if they are, that they won't think to apply it. The basic arguments of this and similar articles are along the lines that digital audio is just a theory/model, models are not reality, theories are theories rather than absolute proof, science doesn't know everything and therefore it's just childish to accept on faith that there is no possibility of there being anything more than only zero's and one's (binary data bits). The reason this is nonsense is because these arguments do not matter, they are totally irrelevant! Let's pretend for a moment that the proven maths/science and demonstrated facts don't exist and assume hypothetically that there definitely is "something else", something other than just zero's and ones. A digital to analogue converter chip is by definition digital and therefore it's designed to accept only zeros and ones, as with all digital devices it's programmed (with zeros and ones) to perform instructions/calculations on other zeros and ones. Therefore, if we feed this "something else" into a DAC chip there are only two possible outcomes; either the chip is unaware of the existence of that "something else" and therefore completely ignores it or it throws an error/crashes because it only understands zeros and ones. In other words, this "something else" (regardless of what it is) either has absolutely no effect at all or causes there to be no output, no other options are possible. And of course, the same is true of all digital processing units, not just digital audio devices, zeros and ones or nothing.

Personally, I'm convinced by the proven math/science and the lack of any reliable evidence even hinting at the possibility of there being "something else". However, I cannot be absolutely certain there is not something else, all I can be absolutely certain of is that if there is something else, we'll need an entirely new technology for it, it can't be digital audio because digital audio by definition of being "digital" is only zeros and ones. So, whether or not there is "something else" or whether or not I or anyone else is open to the possibility of there being something else is completely irrelevant, as are all the other similar arguments about theories and what science might not know. 

The question about this and similar articles is; why was it written? Either the author is just an idiot who effectively doesn't know what "digital" means or we come right back to point #2B above: If we accept the science and facts, that there can be no audible difference and therefore no reason to buy a competent DAC capable of more than 16/44 and no reason to spend more than $10 on a competent USB cable, where does that leave the digital audio equipment manufacturing/retailing industry? They only have two options. 1. A race to the bottom (who can produce the cheapest competent 16/44 DAC or USB cable) or 2. Marketing! Either simply ignore the science and present some nonsense marketing claims, misrepresent the science to back-up nonsense marketing claims or discredit the science and then any nonsense could be "fact"! Along with other some other time-honoured basic marketing techniques; price point, appearance and testimonials, just to name a few, that's more than enough to exploit the difference between audible and perceivable.

The Design Approach article is basically "_The trouble with applying accepted science to music is we don’t have a reliable objective measurement of how well a piece of equipment conveys the emotion that was conveyed in the original performance._" Which again is complete nonsense! It's not the job of an audio reproduction system to convey or reproduce emotion, that would be the job of an emotion reproduction system (if there were such a thing)! It's the job of the artists and engineers who created the recording to make sure that the audio contains and elicits the desired emotions, then it's just a case of reproducing that audio as accurately as possible. To reproduce/convey the emotion perfectly, the audio reproduction system therefore does not even need any awareness of emotion and entirely contrary to the claim; we can very reliably objectively measure the accuracy of audio reproduction (and therefore the conveyance of whatever the recording contained). The very last thing I would want is an audio reproduction system which markets itself effectively as an emotion reproduction system because that implies it is not trying to accurately reproduce audio (and therefore the art and emotion put into that audio by the artists) but is somehow deciding what it thinks is emotion/art and changing the audio from what the artists intended. This falls under the "misrepresent the science" marketing ploy. And the opening sentence "_Our approach to product development is highly scientific, using blind testing to verify all findings_", is of course just a bold faced lie, as blind testing is not "highly scientific", it's not even lowly scientific! The minimum requirement for science is double blind testing and even then, only with certain provisos and conditions!

The author of the article writes reasonably eloquently, so most likely he/she is not an idiot but is simply employing marketing tactics. However, I can't completely discount the possibility that he/she is simply employing marketing tactics and is also an idiot! 

G


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## theorist

Cartma said:


> 1) All USB cables I tried had their own sound signature as well as a sound signature that match their same line of cables. Same type of situation as digital coax cables carrying the same signature as the same line's power cables and interconnects. I think it's more than just doing it right or doing it wrong.





chef8489 said:


> 2) A usb cable has no sound signature at all.



And we go around the circle again with someone asserting position 1) (which I more or less agree with) and then the same several people coming on the thread asserting position 2) based on their beliefs,  often I assume, derived from their own experiences of the failure of the hypothesis that there is a difference occurring between USB cables when a double-blind testing is used, or perhaps based of extensive other relevant experience, such as years spent in the recording/mixing studio. 

Can anyone suggest a way that we can respect that both positions are valid, at least to the individuals believing them, but in a way that we can continue this thread in a manner that moves the debate on by answer why both camps can have contrary positions. Perhaps this can start by addressing questions such as (one from each camp):

How significant is expectation bias eg marketing hype, self-justification, in forming our opinions/beliefs, or even how we mentally interpret what we hear 

Why double-blind testing has a lot of methodological issues in duplicating the emotional listening experience of reproduced music created by the artist (and skill of the recording engineer), eg the sense of relaxation involved in typical home listening experience versus being involved in  a 'test' situation, etc
Undoubtedly, we could make a pretty long list here from both camps!


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## chef8489

You are transmitting a 1 and a 0 not sound. There can not be any sound influenced from the cable that is the whole point of digital audio. If the cable is not malfunctioning there is no audio charismatics the cable can impart in the audio chain.  While we are at it. I have some beach front property available in Nevada for sale along the Pacific ocean. The purpose of digital audio is to not have anything be able to influence the music from the source to the dac and get as pure and perfect as to the source as possible. Again the only reason why you hear a difference is because you have not done a popper double blind test or your equipment is faulty. 

You know why we are asserting this. Because we have done the testing time and time again, which you all refuse to do thus you contuse to believe in the magical usb cable sound changes.


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## theorist (Sep 14, 2017)

chef8489 said:


> we have done the testing time and time again, which you all refuse to do thus you contuse to believe in the magical usb cable sound changes.



On the contrary, I would love to do a double-blind testing of USB cables in my system and see if I can find any differences to when I swap cables myself.

Accordingly, this weekend I have a friend coming over to swap USB cables in and out randomly for me when I am positioned out of sight of him and my system (although my isolation will be limited by the length of my HP cable) and to record my better/worse rankings. I will test the freeby that came with my Auralic DAC to my Nordost Valhalla 2 USB cable with a US list price of $3500. I will test the two cables against each other on the same track repeatedly (having my friend use the 430HA mute function button when changing the cables so as to not change volume). If I can hear a consistent better/worse difference between the cables, I will then test each of these two cables against a Tellurium Q Blue USB which has a UK retail list cost of 186 pounds. If anyone has any methodological suggestions/protocols  please post them in the next 24 hours and if they are not too difficult to implement I will use them provided they don't impinge on my personal privacy.


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## castleofargh

here is an idea for those who purchase various and expensive USB cables pretty often. do yourself a favor and go buy a soundcard with a real good input, or an audio analyzer for a few hundred bucks. so you can really see how one cable improves your sound, or pisses all over it. and measure the improvements on more than a graph with a dollar axis. I can't claim it will bring peace of mind to everybody, but it's an extra reference. not marketing, not forum hype. simple relative comparison between 2 cables while measuring various stuff at the output of the DAC. not specs done nobody knows how, real signal coming out of your system. if it measures good, you probably have a great system. how cool is that? it's very serious, very real information, the kind that would force @chef8489 to admit that your claims of audible difference aren't in your head so we could move on from doubting everybody, to looking into a specific case with clear information and maybe learn something. 

and if you prefer the "worst" cable after measuring it, look the audio analyzer right in the inputs an tell it "I do what I want!". a machine is not taking away free will(not yet).


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## chef8489

Yes please do, so we can figure out what is either wrong with your system and fix It, or maybe those that do see that there is no sonic difference in their cables as long as they are functing within spec and transfering perfect data without jitter. Cartma.


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## Cartma

chef8489 said:


> You are transmitting a 1 and a 0 not sound. There can not be any sound influenced from the cable that is the whole point of digital audio. If the cable is not malfunctioning there is no audio charismatics the cable can impart in the audio chain.  While we are at it. I have some beach front property available in Nevada for sale along the Pacific ocean. The purpose of digital audio is to not have anything be able to influence the music from the source to the dac and get as pure and perfect as to the source as possible. Again the only reason why you hear a difference is because you have not done a popper double blind test or your equipment is faulty.
> 
> You know why we are asserting this. Because we have done the testing time and time again, which you all refuse to do thus you contuse to believe in the magical usb cable sound changes.



The title of this thread is *Why do USB cables make such a difference?* Not *Do USB cables make a difference?* Titled this in effort to keep people like you out. Every time you post you are going off topic.


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## chef8489

Cartma said:


> The title of this thread is *Why do USB cables make such a difference?* Not *Do USB cables make a difference?* Titled this in effort to keep people like you out. Every time you post you are going off topic.


So your object is to keep the well experienced people out that have done the studies and tests so you can perpuatue the magic and nonesesce. Sorry doesn't work like that and that's why we keep these threads to the sound science sub forum for just that purpose.  one thing I love about head-fi is the community is pretty good about policing itself and calling out bs  audiophile trends that other audiophile groups go all gushy over. This community is pretty good about showing proof and refuting claims and going into great detail at explaining everything. Then the people that contually go down the same path usually don't last long around here. Saw it with power cords and other items. 

It's funny theorist is willing to do the tests and if he were local I would love to have him by and we can chat an run some tests together. But alas different countries. 
You on the other hand have nothing to back up anything you have posted. And by scientific standpoint and purpose of sub and digital audio, what you say makes no sense at all. 
Do something to back up what you say. Throw some evidence behind it other than I paid a lot more and now it sounds better.


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## Brooko

chef8489 said:


> So your object is to keep the well experienced people out that have done the studies and tests so you can perpuatue the magic and nonesesce. Sorry doesn't work like that *and that's why we keep these threads to the sound science sub forum for just that purpose*.  one thing I love about head-fi is the community is pretty good about policing itself and calling out bs  audiophile trends that other audiophile groups go all gushy over. This community is pretty good about showing proof and refuting claims and going into great detail at explaining everything. Then the people that contually go down the same path usually don't last long around here. Saw it with power cords and other items.
> 
> It's funny theorist is willing to do the tests and if he were local I would love to have him by and we can chat an run some tests together. But alas different countries.
> You on the other hand have nothing to back up anything you have posted. And by scientific standpoint and purpose of sub and digital audio, what you say makes no sense at all.
> Do something to back up what you say. Throw some evidence behind it other than I paid a lot more and now it sounds better.



Except that this actually is the "'Cables, Power, Tweaks, Speakers, Accessories (DBT-Free Forum)", and in this case Cartma is correct. This is the place where cable believers can discuss the topic without having to provide proof (ie completely subjective).  What makes me smile a bit though is the title.  By introducing the "why", then you're never going to get the answer unless you take it to Sound Science.  But for this particular forum (chef8489), the rules of engagement in Sound Science don't apply.  Its probably why I'm a bit surprised the thread has taken the turn it has.  And bravo to both theorist and gregorio for having such an informed and informative conversation without the usual escalations.


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## chef8489

I am greatfull theorist is truly open to explore other possibilities. He comes from a great deal of analogue audio knowledge and it shows and I would love to spend hours chatting and exploring audio and music with both with him and gregorio. We are all passionate about music and audio. I am sure we could learn something from each other about something, if not I am sure it would be a great night of conversation and expermitation. 

On the same side, I am willing to do the same and be proven wrong.


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## gregorio

theorist said:


> [1] And we go around the circle again with someone asserting position 1) (which I more or less agree with) and then the same several people coming on the thread asserting position 2) based on their beliefs,  often I assume, derived from their own experiences of the failure of the hypothesis that there is a difference occurring between USB cables when a double-blind testing is used, or perhaps based of extensive other relevant experience, such as years spent in the recording/mixing studio.
> [2] How significant is expectation bias eg marketing hype, self-justification, in forming our opinions/beliefs, or even how we mentally interpret what we hear


1. That (position 2) is not a fair characterization of my position. If it were only a case of my personal experience and the results of double blind tests then I would be far less certain of my position than I am. My personal experience and the results of reliable DBTs contribute to my position but there are a number of other, at least equally important factors; digital audio theory and the maths which supports it, what "digital" actually means and how it demonstrably works and the fact that every explanation of those with position #1 is irrational and contradicts the known, proven and demonstrated facts (with the exception of broken/faulty equipment). I thought I'd made the rationale for my position fairly clear?

2. Exactly how significant expectation bias is, depends on the individual, the efficacy of the marketing, etc. That it is significant (to some degree) is pretty much indisputable and self-evident. As virtually all music is dependent on expectation bias, why would audiophiles be willing to spend money on equipment to reproduce music which they are incapable of appreciating? There are a number of different types of expectation biases, some obvious, some sub-conscious, some which can be consciously changed, some which can change instantly, some which evolve over years and some which never change. Typically we do not have "an" expectation bias but a bunch of simultaneous different expectation biases.



chef8489 said:


> You are transmitting a 1 and a 0 not sound. There can not be any sound influenced from the cable that is the whole point of digital audio. If the cable is not malfunctioning there is no audio charismatics the cable can impart in the audio chain.



I entirely agree with your first and second sentences but not with the third one. The audio chain includes someone/people as the last link in that chain and there are a significant number of factors (of a non-malfunctioning) cable which can affect that link. I believe you are well aware of this and intended to say the digital audio equipment chain rather than just the audio chain. I agree with your point though, it is false to state that USB cables have a sound signature because that is a physical impossibility. However, they can have properties which will make some people perceive that they do (for a period of time). 



Cartma said:


> The title of this thread is *Why do USB cables make such a difference?* Not *Do USB cables make a difference?* Titled this in effort to keep people like you out. Every time you post you are going off topic.



Then you mis-titled the thread and your "effort" was wasted. We are making the point that USB cables do not make a difference to the sound, we are NOT saying that USB cables do not make a difference (for example to what you believe you are hearing). We are therefore NOT "going off topic" and I presume you are stating that we are, simply because you do not like some of the answers you're getting to you question. If you only wanted answers you like, rather than factual answers, you should have stated that in the title. Not sure how you could have done that, maybe something like "What magical properties do audiophile USB cables have?" or "Please post marketing materials from audiophile cable manufacturers/retailers" or "Why do USB cables make such a difference (no science, facts or logic please)?"



theorist said:


> If anyone has any methodological suggestions/protocols please post them in the next 24 hours and if they are not too difficult to implement I will use them provided they don't impinge on my personal privacy.



I commend your openness to try such a test. It's very difficult to do a scientifically valid test of this sort and for the vast majority of us, we don't really need to because we're trying to learn something about ourselves rather than prove something to others or the scientific community. In this respect you appear to be taking fairly reasonable steps to eliminate as many of the most obvious biases as practical but I have a couple of suggestions to remove a few more which shouldn't be too difficult: Try to eliminate any visual or verbal communication with the person switching the cables. You could do this by you both having a piece of paper, you writing down your observations for test 1, 2, etc., and the person switching the cables writing down which cable was used for test 1, 2, etc. Something else which is relatively simple, make sure the person switching the cable doesn't always switch to the different cable, some of the tests should be unplugging the cable and then plugging that same cable back in again (don't skip the uplugging and plugging back in again steps). Good luck.

G


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## canthearyou

I have a real nice USB cable and if I listen carefully I can hear a few "2's" along with the "1's" and "0's". That adds a lot to the soundstage.

Jk! But I am enjoying this thread.


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## gregorio

canthearyou said:


> I have a real nice USB cable and if I listen carefully I can hear a few "2's" along with the "1's" and "0's". That adds a lot to the soundstage. ... Jk! But I am enjoying this thread.



Ah, so you're listening in stereo and if the left channel is at 1 at the same time that the right channel is at 1, then everyone knows that 1 + 1 = 2, so you must be hearing some twos. I'm sure I've heard some sixes when listening to 5.1 surround. Obviously though, I use a USB cable which is six times more expensive than the one I use for mono recordings, just to be sure I'm getting bit perfect results! 

G


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## Cartma (Sep 17, 2017)

Hey *theorist*,

I keep losing the low end impact. Did you find this with your Nordost as they burned in? I noticed this with another Nordost system. Has to be the USB cable as it's the only thing I changed in quite some time.


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## Brooko

How exactly can a cable burn-in?  What electrical properties change?  You realise this is impossible right?


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## gregorio

Cartma said:


> [1] I keep losing the low end impact. Did you find this with your Nordost as they burned in?
> [2] Has to be the USB cable as its they only thing I changed in quite some time.



1. You really didn't think about that statement before you posted it. If you had, you would have very quickly realised why it cannot be true. Let me explain: A USB cable is a digital interconnect, so if there really were a difference in the sound (a loss of "low end impact") before and after burn in, it can only be because the cable is changing the digital data (zeros and ones) it is transferring before burn in compared to after burn in. If this really did occur with digital interconnects, think of the consequences. All mobile phones, tablets, laptops, computers, digital TVs, etc., would constantly crash when you first bought them until all the digital interconnects inside them had "burnt in" and became capable of transferring the digital data perfectly. There are billions of digital devices in the world, all packed with digital interconnects and all of them (with the exception of the odd broken one) work perfectly straight out of the box, none of them require a burn in period before they can transfer digital data between their internal components perfectly and therefore function.

2. It's good that you are using logic to work out what's going on (the logical device of deduction through a process of elimination). If you eliminate all the other variables (the items which have not changed), then whatever is left (that has changed) absolutely MUST be responsible for any differences you are hearing. Nothing wrong with that logic at all  ... but of course it's logical and only actually works if you really have eliminated all the other potential variables! Unfortunately though, you haven't, there's still one other variable remaining, your perception! Using your own process of logic, that whatever is left absolutely must be responsible, you are left with two possibilities, the digital interconnect changes or your perception does: The digital interconnect changing is addressed in point #1 above, the numerous digital interconnects in each of the billions of digital devices which obviously do not change. So what about the other possibility, of your perception changing? When you listen to a recording for the first time do you perceive absolutely all the details, or over time, as you listen to the recording several/numerous times do you perceive more details which you did not perceive on the first hearing? If it's the latter, then your perception is obviously changing. Applying your own logic to your own observations (of your perception changing and of countless digital interconnects in the digital devices you've owned/seen which do not need to "burn in" in order to function), the only thing that's left which absolutely MUST be responsible for any differences you are hearing is your changing perception! So, let's do a tally: On one side there's all the science, proven maths, engineering, demonstrated facts, your own observations and your own logic, while on the other side there's what, marketing materials and what a relatively small group of other audiophiles believe! Which side are you going to throw out?

G


----------



## castleofargh

Cartma said:


> Hey *theorist*,
> 
> I keep losing the low end impact. Did you find this with your Nordost as they burned in? I noticed this with another Nordost system. Has to be the USB cable as its they only thing I changed in quite some time.


so you really go believe in even the most controversial ideas so long as it might be cherry picked to support your feelings. and at the same time you play the offended card if someone suggests a logical fallacy. nice explosive combo and my cue to unsubscribe before I get hit. if someday you actually wish to answer your own questions instead of whatever game of "am I right or am I right?" you're playing now, just loop your DAC into your soundcard get some free RTA or whatever and check for real how much low end you lose over time with your next cable.


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## Cartma

Well I don't know how or why burn-in is real, but it's real. Real with even SPDIF digital cables, so why not USB? Like I said, the signature of this USB cable match's the signature of other Heimdall 2 cables. So I am treating the USB as any other cable be it power, speaker, or interconnects.


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## gregorio

Cartma said:


> Well I don't know how or why burn-in is real, but it's real.



I didn't ask if you knew why burn in was real, I asked if you were willing to ignore your own observations and your own logic (plus all the demonstrated facts) in favour of marketing and audiophile belief, guess you've given us your answer. The power of marketing is impressive but I couldn't imagine allowing it to dominate/override my own observations, my own logic and such demonstrated facts! That's just me though, there's all sorts of people in this world and I suppose there must be many like you and that's why companies spend the countless billions they do on marketing.

G


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## Cartma

gregorio said:


> I didn't ask if you knew why burn in was real
> G


You're right you didn't, I was replying to Brooko.


----------



## gregorio

Cartma said:


> You're right you didn't, I was replying to Brooko.



Your reply (to Brooko) also answers my question though, so thanks.

G


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## chef8489

Cartma said:


> Well I don't know how or why burn-in is real, but it's real. Real with even SPDIF digital cables, so why not USB? Like I said, the signature of this USB cable match's the signature of other Heimdall 2 cables. So I am treating the USB as any other cable be it power, speaker, or interconnects.


Burn in does not occure with spdif cables either. That also is ridiculous. First of all it is a digital signal, optical  is light passing through a clear plastic cable. No electricity is flowing so how can burn in occure?. Coaxial spdif is digital signal similar to a usb cable. If burn in occurred you would have errors from the start and the cable would be useless until burned in and they would do this at the factory before shipping and you would not notice a difference because who in there right mind would send out a cable that would not work from plugging in from the start, but that is not how it is and you get perfect transfers and no cable burn in as it is impossible for a digital cable to burn in as well as a digital cable to have a sound signature. The more you post the more you prove you have no credibility. You are driving away the people that were sticking up for you with your ridiculous posts and when people dont agree with you you just go deeper into your delusions and get butthurt when everyone does not agree.


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## Leo-

Unfortunately I don't have a mini to mini cable with me and i will be out on a business trip next week, otherwise I would record it for all to listen. Perhaps I can do it on the way back. As I suggested before, it is fairly easy to verify that USB cables don't carry only digital signals but they carry any electrical noise that is fed straight through the USB interface and DAC chip unles it's filtered out on the way. 

I have a liquid cooled PC with PWM fans and a pump. When I connect it to my Mojo via USB, I hear a high frequency clicking noise through the headphones. No digital signal whatsoever passing through the cables. The Mojo is dead silent when disconnected, when connected to my Android phone in airplane mode or through my ultraRendu+LPS1 combo (all without any audio stream through the USB). I also don't hear clicking noise when the PC is connected directly to my stereo DAC - the reason is that the stereo DAC does not connect the USB power. 

I don't see how one could explain this without acknowledging that USB cables carry more than "1s and 0s".


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## Cartma (Sep 16, 2017)

chef8489 said:


> Burn in does not occure with spdif cables either. That also is ridiculous. First of all it is a digital signal, optical  is light passing through a clear plastic cable. No electricity is flowing so how can burn in occure?. Coaxial spdif is digital signal similar to a usb cable. If burn in occurred you would have errors from the start and the cable would be useless until burned in and they would do this at the factory before shipping and you would not notice a difference because who in there right mind would send out a cable that would not work from plugging in from the start, but that is not how it is and you get perfect transfers and no cable burn in as it is impossible for a digital cable to burn in as well as a digital cable to have a sound signature. The more you post the more you prove you have no credibility. You are driving away the people that were sticking up for you with your ridiculous posts and when people dont agree with you you just go deeper into your delusions and get butthurt when everyone does not agree.



I'm not talking about optical/toslink. I'm talking about coax.


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## chef8489 (Sep 16, 2017)

Leo- said:


> Unfortunately I don't have a mini to mini cable with me and i will be out on a business trip next week, otherwise I would record it for all to listen. Perhaps I can do it on the way back. As I suggested before, it is fairly easy to verify that USB cables don't carry only digital signals but they carry any electrical noise that is fed straight through the USB interface and DAC chip unles it's filtered out on the way.
> 
> I have a liquid cooled PC with PWM fans and a pump. When I connect it to my Mojo via USB, I hear a high frequency clicking noise through the headphones. No digital signal whatsoever passing through the cables. The Mojo is dead silent when disconnected, when connected to my Android phone in airplane mode or through my ultraRendu+LPS1 combo (all without any audio stream through the USB). I also don't hear clicking noise when the PC is connected directly to my stereo DAC - the reason is that the stereo DAC does not connect the USB power.
> 
> I don't see how one could explain this without acknowledging that USB cables carry more than "1s and 0s".


You have serious issues then. I also have a liquid cooled pc, dual graphics cards about 13 fans in my system and using a 12.00 led Amazon sub cable and my dac is dead silent when I have hooked up several. But as far as data that the dac decodes it is only 1 and zeros. Everything else would be considered distortion if it is passed along. A digital cable does not burn in and carry sound characteristics. A usb cable carries 1 and zeros and if powered it carries a charge. If it does not then it only carries 1 and zeroes. Now with interference from systems that need to be isolated that you are referring to it comes down to the source and how well the dac is made.


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## Leo-

chef8489 said:


> You have serious issues then. I also have a liquid cooled pc, dual graphics cards about 13 fans in my system and using a 12.00 led Amazon sub cable and my dac is dead silent when I have hooked up several.



This is just to show that USB carries also noise, and does prove the point. The same is true for other noise sources such as from switching power supplies, however since they are high frequency you don't listen directly to them (the capacitors in your system will see this noise though). 

I don't use this PC for audio at all, I have a separate setup for the stereo.


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## chef8489 (Sep 16, 2017)

Leo- said:


> This is just to show that USB carries also noise, and does prove the point. The same is true for other noise sources such as from switching power supplies, however since they are high frequency you don't listen directly to them (the capacitors in your system will see this noise though).
> 
> I don't use this PC for audio at all, I have a separate setup for the stereo.


Yes I adjusted my post. In some circumstances there can be times where noise can be transferred. The solution would not be buy an expensive usb cable but fix the source. The noise is not a sound signature though for Just for Cartma reference. It is not supposed to be there. Usually would see this problem with a usb powered dac vs a externally powered dac by a wallwart.


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## Arpiben

Leo- said:


> Unfortunately I don't have a mini to mini cable with me and i will be out on a business trip next week, otherwise I would record it for all to listen. Perhaps I can do it on the way back. As I suggested before, it is fairly easy to verify that USB cables don't carry only digital signals but they carry any electrical noise that is fed straight through the USB interface and DAC chip unles it's filtered out on the way.
> 
> I have a liquid cooled PC with PWM fans and a pump. When I connect it to my Mojo via USB, I hear a high frequency clicking noise through the headphones. No digital signal whatsoever passing through the cables. The Mojo is dead silent when disconnected, when connected to my Android phone in airplane mode or through my ultraRendu+LPS1 combo (all without any audio stream through the USB). I also don't hear clicking noise when the PC is connected directly to my stereo DAC - the reason is that the stereo DAC does not connect the USB power.
> 
> I don't see how one could explain this without acknowledging that USB cables carry more than "1s and 0s".



The situation you are facing is not due to '0' and '1' being altered or modified but to 'noise' currants circulating through Vbus/Ground cables.


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## Leo-

Sure mate, noise is much more of an issue in AC powered systems. With battery powered it should not be a problem - therefore I wouldn't even bother with that with a portable DAP. From the other side, portable gear have RF issues since they have very little shielding compared to full sized equipment (the Mojo is particularly bad in this respect compared to my other gear). 

You're right that electrical issues are worse on USB powered DACs. Aside from getting good quality power from the USB, there is the problem of feeding a high current through the +5V rail which can be in the order of 1A. This current creates a magnetic field which in turn upsets the signal rails. I read from John Svenson (I think - quoting from memory) wrote that in theory this should be taken care by the USB design, since by design the USB signal is balanced but in practice it does not work so well. Self powered DACs are much better in this respect.


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## chef8489

Leo- said:


> Sure mate, noise is much more of an issue in AC powered systems. With battery powered it should not be a problem - therefore I wouldn't even bother with that with a portable DAP. From the other side, portable gear have RF issues since they have very little shielding compared to full sized equipment (the Mojo is particularly bad in this respect compared to my other gear).
> 
> You're right that electrical issues are worse on USB powered DACs. Aside from getting good quality power from the USB, there is the problem of feeding a high current through the +5V rail which can be in the order of 1A. This current creates a magnetic field which in turn upsets the signal rails. I read from John Svenson (I think - quoting from memory) wrote that in theory this should be taken care by the USB design, since by design the USB signal is balanced but in practice it does not work so well. Self powered DACs are much better in this respect.


Thats the whole reason I went with a dac for this system I was getting horrid noise out of the speakers through the sound card when I moved and had to get rid of my good speakers that were run off spdif. When I hook headphones into my speakers I hear so much noise from the pc and the motherboard. I had to have a seperate dac and amp to isolate the noise. Watercooling is a noisy environment. 


Arpiben said:


> The situation you are facing is not due to '0' and '1' being altered or modified but to 'noise' currants circulating through Vbus/Ground cables.


Yes and does not need burn in either. For Cartma benefit. Again something in the source needs to be fixed to prevent this or the cable is faulty and needs replaced but not with an expensive one.


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## Leo-

Again, this PC is not part of my audio setup is just my old gaming PC. 



Arpiben said:


> The situation you are facing is not due to '0' and '1' being altered or modified but to 'noise' currants circulating through Vbus/Ground cables.



If noise gets passed to the analog circuitry it may indeed alter the sound. There is also the problem of leaking currents through the ground connection, which is an audible effect transmitted by the cable however switching the cable should not change this as far as I understand. An excellent discussion is here:

https://uptoneaudio.com/pages/j-swenson-tech-corner

Another effect that I didn't see yet mentioned is the cable impedance. USB cables have nominally 90 Ohms impedance. As far as I understand, deviations from the spec may affect the signal rise time of the digital signal, which incurrs in jitter - the data itself should be quite robust to it, therefore you still get no errors in hte data transmission. The worst case is when there is differential impedance between the data paths which may completely mess up the timing of the signal. How exactly does this degrade the signal in an asynchronous USB setup I don't exactly understand, however as usual the devil is in the details. This is discussed for example here.


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## theorist

Cartma said:


> Hey *theorist*,
> 
> I keep losing the low end impact. Did you find this with your Nordost as they burned in? I noticed this with another Nordost system. Has to be the USB cable as its they only thing I changed in quite some time.



Sorry for my slow reply to you Cartma, but yesterday I was rather busy testing USB cables with a friend. I am yet to complete writing up my report which I will post later today on this thread, once finished. While the results will not surprise you, or others of our camp, they will put the cat among the pigeons for those who believe that all properly made to spec USB cables must sound identical, ie they can have no impact on the overall system sound. 

Anyhow, in the burn-in of my Nordost Valhalla 2 USB cable (Nordost recommended 200 hours of burn-in for that cable) back in February, I did experience some issues after about 50 hours of burn-in which I reported in post #32 of this thread at the end of last month. Of course, it set the usual band of our friends saying that what I reported, and could actually measure (crudely by using the clock bandwidth settings of my Vega DAC), cannot possibly happen with an USB cable, as there is no such thing of burn-in effects with digital cables. Anyhow, this was not a loss of 'low end impact', rather an issue of what I assumed was to do with increased jitter caused somehow by the cable (as this was the only factor of change in the system), and it did come good again after about another 50 hours of further burn-in.


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## Leo-

chef8489 said:


> Thats the whole reason I went with a dac for this system I was getting horrid noise out of the speakers through the sound card when I moved and had to get rid of my good speakers that were run off spdif. When I hook headphones into my speakers I hear so much noise from the pc and the motherboard. I had to have a seperate dac and amp to isolate the noise. Watercooling is a noisy environment.



The micro/ultraRendu is a nice option to power a DAC without external power supply. However, if you use your computer for videos or gaming it will not work nicely since there is some lag due to buffering. Probably a Regen would work well, not sure if it has appreciable delay. They are able to isolate the source and provide clean power to the DAC (as long as you power them with a good PSU). In the past, I used SPDIF from the computer, nowadays couldn't care less about the PC sound anymore - just rarelyI hook my RSA Predator to it.


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## chef8489 (Sep 16, 2017)

I use the Modi multibit and the vali 2 and works quite well when headphones are needed. I have spdif and usb hooked up and neither has any noise for my gaming pc.


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## theorist

*USB Cable Double-blind Shoot Out.*

First off, double-blind testing is exhausting work, if interesting!

I compared three USB A/B cables:

·      a generic Belkin 1.8 m cable that costs locally about US$12 (originally, I was going to use the ‘free’ one that came with my Auralic Vega DAC, but the one I had to hand that I thought this was turned out to be an A/Micro from one of my DAPs when I looked more closely at it);

·      a 1m Tellurium Q Blue with a UK list price of £186 (about US$250); and,

·      a 1m Nordost Valhalla 2 with a US list at US$3,500 (although I doubt if anyone ever pays near this, I certainly did not).

You can see my rig and set up below, its connected fully balanced. I used my Focal Utopias, which I find my best resolving of HPs for critical listening. To get as close to actual double-blind as possible (I could still hear my friend’s cable changing) I reversed my Eames lounge chair and ottoman facing away from my gear and sat about 1.5 metres away (as far as my 6 ft. Heimdall 2 balanced HP cable would permit). I did not look behind me for the over two hours of careful listening, except when taking a 10 minute break between each round of USB cable pairs (with the first cable being inserted for the next round only after I looked away). Following gregorio’s suggested protocol we agreed to not talk while testing, with my friend writing the cable in order of use for each pairing and me the decision whether the second cable was ‘better/worse’ than the first for each pairing, but we modified this while underway (see below).

Let’s call my friend Freud. I’m sure you can get the psychoanalytical reference, if not, google “Freud’s couch” (Freud intentionally sat out of sight of his patient to avoid giving visual facial clues) and think how my Eames chair/ottoman was now arranged. The only influence I was under during the listening was coffee. But, after we finished, believe me, we both deserved something stronger and accordingly had a nice dram of malt whisky!

I listen to the same track, or part of it, over and over, twenty times for each cable pairing round. This was Laura Marling’s ‘The Valley’ from Semper Femina (5:40).

At first, we followed the protocol suggested by gregorio, but modified it after the third pairing of the first round to avoid what proved to be unnecessary long listening times. In the first round’s first three pairings of listens with each cable, I went through the full track once with each cable before writing my decision down of better or worse after hearing the second cable. However, by the third pairing of the first Belkin/Nordost round, I pretty confidentially thought I knew very early in the listening of the track which cable was being used, and so, breaking the silence protocol, I stated which cable I thought was which at the end of this third pairing after writing down my better/worse answer. Freud confirmed that I was correct. So, we modified the protocol for the rest of the first round and then largely followed this in the subsequent two rounds, where we then played through the full track twice only for the first pairing of each round.    

Subsequently, I called out, which cable I thought it was and if it was the second cable, wrote down if it was better/worse, Freud then stopped the track and changed the cable over. In addition, following gregorio’s other protocol suggestion, rather than swapping each cable ten times in the 10 pair round, one after the other in random order; once for each cable in each round (but never the first pairing), Freud only pretended to change the cable, when he had not (while unplugging and then re-plugging it – since I could hear the sound of cable changing in my seat, similarly he did the unplugging/re-plugging if the cable order was changed for the next pairing, as the same cable played immediately again in the new paired test).

*Findings Round One – Belkin vs Nordost Valhalla 2:*

Better: Nordost 4, Worse: Belkin 4, Same cable: twice correctly identified

There were subtle but consistent differences between both cables that were readily apparent from the very first pairing. The guitar ‘E’ base string strum/thumb pick (I assume) at the start and then after 15 seconds every five or so seconds was almost without significant musical consequence with the Belkin, it was there but just part of the overall musical background, while with the Nordost, it stood out and gave a foundation and important structure to the rest of the music being presented. Further, and especially after about halfway through the track the Belkin, relatively speaking, presented the music sounding thicker, more like a treacle, with all the individual components merged/stuck together – with little palpability/separation – and there was especially little or no separation of the violins, in contrast to what I could hear distinctly with the Nordost cable. Put simply and metaphorically, the Nordost made me more relaxed when listen to the whole presentation and the musical bits and spaces between the musical notes within it, while the Belkin made me unconsciously tense-up at the lumpy undifferentiated mass being presented that was hard and unattractive to audibly digest. But despite this rather extreme way that I have expressed what I heard in trying to describe the differences I perceived between the two cables, these were actually pretty small differences of overall scale – hardly night and day – and unlikely to be noticed without concentrated attention and careful listening to the music of the same track with the two very different in price cables.

*Findings Round Two – Tellurium Q Blue vs Belkin:*

Better: Tellurium 4, Worse: Belkin 4, Same: twice correctly identified

A bit of non-blind corruption here, I already knew the ‘treacle-ly’ sound of the Belkin from the first dual pairing and the dynamic liveliness of the Tellurium (which is the Tellurium house sound for all their types of cables, including digital) just jumped out at me from the first few seconds of listening (even though I have not used this cable at all for a couple of years). Indeed, the differences were even more strongly initially apparent that the differences with the Nordost, with the Tellurium undoubtedly sounding better and more musically interesting.

*Findings Round Three – Tellurium Q Blue vs Nordost Valhalla 2:*

Better: Nordost 4, Worse: Tellurium 4, Same: twice correctly identified

Some expectation bias could easily be occurring here. I knew which cable was which from the first few seconds of listening to each. So, it is understandable to choose the one I dropped over ten times as much on as better, but ultimately the Nordost was, at least for me, just a more relaxed and enjoyable listen with greater palpability. While the Tellurium ‘sounded’ in some ways more musically dynamic, it was also a bit etched/outlined or leading-edged focused with the substance of the music notes themselves a bit shallow and hollow, at least compared to the Nordost, whose sound I clearly preferred.

*Discussion:*

Amazingly, despite the very clear result, I was surprised by how similar these very different in price cables actually were. I can see why people can say all USB cables sound the same to them. These were not in your face differences that I heard. Indeed, I would probably not care about them at all, if I could even hear them, when driving in my car with music shuffling MP3 mode from my old iPod to the car stereo. Rather, these differences are the kind of things you are looking for and hope to achieve with your rig in our hobby when seriously listening, in our impossible, hence endless search for some absolute ‘perfect’ sound (which we know can’t exist).

*Addendum:*

Understandably, Freud wanted a listen. He is no Head-Flyer or audiophile, his iPhone and buds are his thing when he does bother to listen to music (and he actually prefers watching YouTube videos). So, we swapped roles (and with malt in hand), he listed to the full track twice with the, unknown to him, first the Belkin cable followed by the Nordost. When asked if the second cable was better or worse, Freud replied they sounded exactly the same. I then suggested that he just listen to the effect of the base note at the very start and then repeated about 15 seconds later and then a few seconds later and so on and compare the two cables just based on the sound of those base notes. I played about the first minute of the track, changed cables, and replayed the first minute again. Freud said: ‘do it again’. After the third pairing he said: ‘the Nordost was the second cable, wasn’t it?’ I said: ‘yap’!

PS In an ideal world I wish I could have done this test with chef8489 also just to for the great discussion we would have had afterwards!


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## Arpiben (Sep 17, 2017)

Leo- said:


> Again, this PC is not part of my audio setup is just my old gaming PC.
> 
> 
> 
> ...



Keep in mind that data rates involved in USB audio vary from 1.4Mbps (44.1kHz/16bits) up to around 50Mbps (768kHz/32bits).
USB2.0 cables are able to carry rates up to 480Mbps (HS High Speed).
At audio data rates no use to worry.
A proper cable doesn't add jitter.
A proper cable doesn't reduce jitter.

A cable impedance only matters when it is associated with loads at both ends.
In our case, when looking at impedance matching you can not dissociate source (DAP/PC) , cable and load (DAC) impedances. Dealing with USB, there are specifications for all. The USB cable spec.,for example, is given at 90 Ohms +/-10% .
Again even with imperfections, data integrity is not in danger.
Again a perfect impedance cable will improve nothing if DAP and DAC have improper impedances.

I have no experience with expensive USB cables. I am also not denying that some may perceive differences with their systems without brain doing tricks.
But for such cases, I would like to look at DAC's analog large spectrum (0Hz-1GHz)
output.
Maybe such USB cables are tuned for BBC world radio (joke)?

Edited: Quote issues corrected


----------



## Leo-

Arpiben said:


> At audio data rates no use to worry.
> A proper cable doesn't add jitter.
> A proper cable doesn't reduce jitter.
> Edited: Quote issues corrected



Any digital transmission adds timing errors to the data, which perhaps doesn't matter for 99.9% of the applications other than audio, which relies on the data transmission synchronicity for timing information. 
All cables subject to noise at the right frequency bands will add jitter to the signal. 



Arpiben said:


> A cable impedance only matters when it is associated with loads at both ends.
> In our case, when looking at impedance matching you can not dissociate source (DAP/PC) , cable and load (DAC) impedances. Dealing with USB, there are specifications for all. The USB cable spec.,for example, is given at 90 Ohms +/-10% .
> Again even with imperfections, data integrity is not in danger.
> Again a perfect impedance cable will improve nothing if DAP and DAC have improper impedances.
> Edited: Quote issues corrected



The receiver circuit is the load, and those are mostly everybody uses the same circuits. Once the impedance is outside the ideal value, the receiver will still operate, but may not be as accurate in identifying the timings of the incoming data. This error can be bypassed if you buffer the data at the receiver or use master clocks, however in most cases the data is received "as is" and passed on. 

In other words, USB audio is _never_ transmitted perfectly and in theory there is _always_ some loss in timing information. If you're interested I may show you how it works.


----------



## Arpiben

Leo- said:


> Any digital transmission adds timing errors to the data, which perhaps doesn't matter for 99.9% of the applications other than audio, which relies on the data transmission synchronicity for timing information.
> All cables subject to noise at the right frequency bands will add jitter to the signal.
> 
> 
> ...



I am always interested in learning new things. For sure I don't know in details how XMOS/ATMEL/etc MCUs are dealing with priorities when dealing with USB PCM decoding.
As far as I know ( feel free correcting me), there is no clock recovery from USB signal as opposed with SPDIF(embedded).
Dealing with asynchronous transfer mode for controlling USB chips buffer size, I am expecting those to correct most of input jitter issues without need at all of expensive USB cables.
Dealing with output residual jitter from those chips and how it is interacting with other noises inside DAC it is a different matter at least for me.

Since I have more experience in digital transmission and network synchronisation issues I tend to get annoyed/sceptical when reading at audio manufacturers papers pretending improving timing issues but if you notice well they never quantify the improvements or tell you if it really matters.


----------



## Clive101

chef8489 said:


> Yes I adjusted my post. In some circumstances there can be times where noise can be transferred. The solution would not be buy an expensive usb cable but fix the source. The noise is not a sound signature though for Just for Cartma reference. It is not supposed to be there. Usually would see this problem with a usb powered dac vs a externally powered dac by a wallwart.


Ah So USB cables carry more than zeros and ones..!


----------



## Leo-

Arpiben said:


> I am always interested in learning new things. For sure I don't know in details how XMOS/ATMEL/etc MCUs are dealing with priorities when dealing with USB PCM decoding.
> As far as I know ( feel free correcting me), there is no clock recovery from USB signal as opposed with SPDIF(embedded).
> Dealing with asynchronous transfer mode for controlling USB chips buffer size, I am expecting those to correct most of input jitter issues without need at all of expensive USB cables.
> Dealing with output residual jitter from those chips and how it is interacting with other noises inside DAC it is a different matter at least for me.
> ...



It is good to exchange knowledge even when if we're not experts in a certain subject. What you said is almost correct, except... something that I also overlooked in the past. In reality, in an "asynchronous USB" normally it just means that it is the receiver clock which controls the data stream. There is no reclock whatsoever when the data is received, and the signal is passed as received to the DAC section. In order to get rid of this added jitter, you have to throw away the timing information from the signal and regenerate the stream from scratch. This is possible since USB has a constant sampling rate (the term asynchronous is just a catchy word), this can be done with a memory and a clock. That's basically what an Uptone Regen or other very few DACs do. I listened to the NAIM NDS and it is superb even playing from a junk source, however they use nothing less than 10 (!) clocks of different frequencies to regenerate the signal. Others like DCS have the option of using Master Clocks which are even more complicated (that's what recording studios use also to synchronise the times across all different recording equipment). 

Have a look at this paper from Naim, especially Figure 3 with simulated jitter - they're simply showing that with 3ns of jitter a complete new note (almost an A) appears in the sample! 

https://www.naimaudio.com/sites/def...files/dac-v1_asynchronous-usb_mwp_jan13_0.pdf


----------



## Triode User

Clive101 said:


> Ah So USB cables carry more than zeros and ones..!



Ah, yes. The knub of the problem. Nurse, please pass me another ferrite core.


----------



## Arpiben

For the pleasure of discussion only, I found that specific example a bit overexagerated since when looking at figure 4&5 jitter curves you would have noticed nothing.
I also prefer to see jitter curves covering the full frequency range rather than only +/-4kHz around Fs/4.

For a concrete example let's take a USB DAC 'A' oversampling 2048 times and having Nth order noise shaping applied. With such, DAC 'A' can show remarkable J-Test / Sin jitter curves with peaks under -130dB ( or even much better).
Let me connect DAC 'A' to my noisy desktop computer and perform again jitter. Then I have -70dB peaks due to AC harmonics...Is it my USB cable fault? Is it my USB cable altering the 'timing' accuracy?


----------



## Leo-

One cannot compare the charts. One is signal, the other is noise...



Triode User said:


> Ah, yes. The knub of the problem. Nurse, please pass me another ferrite core.



Ferrite prices just surged 0.9%


----------



## chef8489

This is not double blind testing for the record.


Clive101 said:


> Ah So USB cables carry more than zeros and ones..!


carries electricity.


----------



## Duy Le

theorist said:


> *USB Cable Double-blind Shoot Out.*
> 
> First off, double-blind testing is exhausting work, if interesting!
> 
> ...


Amazing test and clearly evidence.
If someone can't hear the different, he is very lucky and he should feel happiness.
If someone can hear the different, sorry to his wallet but he should feel more happiness.


----------



## Arpiben (Sep 22, 2017)

Leo- said:


> One cannot compare the charts. One is signal, the other is noise...



Agreed.
But does jittering an USB audio data input with a sinus 1us peak to peak at a frequency of 2 kHz make sense ?
Looking at USB2.0 specs 7.1.13 Source data jitter, 7.1.15 Receiver data jitter & 7.1.2 ...Eye pattern, I am not sure at all.
That is the reason I was finding it exagerated.

I admit that I am more comfortable with the AES3 input jitter template hereunder.
Wiith AES3 protocol, at 48kHz frame rate, one Unit Interval  U.I =163ns.
Jittering with 1us pp at 2kHz is well above input tolerances.







https://imgur.com/a/llAm2

Edited: *J-Test with USB/HDMI*

Since when dealing with USB (or HDMI) audio content is sent in packets and not as a synchronous continuous stream the J-Test signal can not induce jitter in such signals (USB/HDMI).
Because we can’t stimulate jitter at a particular frequency, unless there is a specific coherent interference source causing it, any jitter that is present may very likely be random and will just cause an increase in the noise floor with no visible spikes in the FFT.
In other words, J-Tests signals used for jitter characterization of USB/HDMI digital signals in manufacturers or audiophile papers/reviews is non sense not to say B.S.

For those interested in J-Test:
The J-test signal has two components. The first is an undithered sine wave at 1/4 the digital sample rate (12 kHz for a 48 kHz sample rate), with an amplitude of one half of full scale. The second component is an undithered low-frequency square wave with an amplitude of 1 LSB (least significant bit). The frequency is not critical, but for a sample frequency of 48 kHz, a rate of 250 Hz is normally used, as that makes the signal synchronous with the AES3 channel status block of 192 samples. At only 1 LSB, the 250 Hz signal is extremely small and only apparent when jitter is present.


----------



## gregorio

theorist said:


> *USB Cable Double-blind Shoot Out.*



If it were me, I would want to know what caused your results. The first thing I would do is loop the output of your DAC back into an ADC with each of the cables attached and compare the results. A simple null test would be enough to show if the differences are massive enough to be audible. If not, then your test was fatally flawed in some way, if they are, then your test was likely accurate and it's on to the next step, of finding out why. The most likely reason would be different USB cables providing differing levels of ground/power isolation and an incompetently designed/broken DAC. But that would be the next step, following a validation of your blind test.



theorist said:


> Amazingly, despite the very clear result, I was surprised by how similar these very different in price cables actually were. I can see why people can say all USB cables sound the same to them.



No, you can see ONE reason why some people might say all USB cables sound the same. There are others, for example; someone may not have an incompetently designed DAC and cannot hear a difference between USB cables because there is none. I'm sure, in the example of a faulty/incompetent DAC, with my reproduction equipment I could also hear a difference between some USB cables.



Duy Le said:


> [1] Amazing test and clearly evidence.
> [2] If someone can hear the different, sorry to his wallet but he should feel more happiness.



1. It's an unvalidated test and therefore we don't know if it's "amazing". I'm surprised you can be amazed by this single blind test, what would a controlled double blind test with a large sample size do to you? Even if we assume this is a valid test, that's one piece of clear evidence we have, what about all the other clear evidence?

2. How do you work that out? He should feel less happiness because the only reliable evidence for USB cables making a difference is in conjunction with a faulty DAC and how would knowing that you've bought a faulty DAC make someone feel more happiness? I suppose you could just refuse to accept or remain ignorant of the fact you've wasted your money on a faulty DAC. In which case, the old cliche "ignorance is bliss", could indeed bring more happiness!

G


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## Arpiben (Sep 22, 2017)

@theorist

Another test suggestion in case of ADC not available.
Using the same equipments listen to your test audio files when connecting source and DAC with *optical* (if possible).You will have three different settings:

Plug optical cable in between Source and DAC with no other cable connections between them.
Plug USB A cable at both ends ( Source & DAC). Keep listenning through optical and check if you notice differences.
Plug USB B cable at both ends ( Source & DAC). Keep listenning through optical and check if you notice differences.
If you notice differences with those three settings when listenning through optical then most probably as mentionned by @gregorio you may have cable induced noises.

Edited: added more details


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## Duy Le (Sep 22, 2017)

gregorio said:


> 2. How do you work that out? He should feel less happiness because the only reliable evidence for USB cables making a difference is in conjunction with a faulty DAC and how would knowing that you've bought a faulty DAC make someone feel more happiness? I suppose you could just refuse to accept or remain ignorant of the fact you've wasted your money on a faulty DAC. In which case, the old cliche "ignorance is bliss", could indeed bring more happiness!
> 
> G


The sound signature is the same but the soundstage is different because the better USB cable carries less noise and more exactly signal (I mean the signal does not loss or incorrect). And the better source you have (music server vs PC) or the shorter cable you have, the different is more subtle.


----------



## gregorio

Duy Le said:


> The sound signature is the same but the soundstage is different because the better USB cable carries less noise and more exactly signal (I mean the signal does not loss or incorrect). And the better source you have (music server vs PC) or the shorter cable you have, the different is more subtle.



No, it's got nothing to do with the data signal, there is no data loss or change in the data, digital data is immune to noise, that's why digital audio was invented and developed in the first place! If a USB cable or source really does cause a difference in your DAC's output, it's because you have a faulty/incompetently designed DAC!

G


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## Duy Le (Sep 22, 2017)

gregorio said:


> No, it's got nothing to do with the data signal, there is no data loss or change in the data, digital data is immune to noise, that's why digital audio was invented and developed in the first place! If a USB cable or source really does cause a difference in your DAC's output, it's because you have a faulty/incompetently designed DAC!
> 
> G


If the signal cannot be effected, why does cable manufacturer try to isolate electric line from signal line and many armors are applied? I think more jitters can be produced on the worst cable than the good cable. Do you mean the better cable should be used for the poorer quality DAC?
I'd like to notice that I don't recommend to buy the expensive USB cable, but the good designed and good built cable should be a good choice.
Sorry for my English skill, it is not my native language.


----------



## theorist

gregorio said:


> If it were me, I would want to know what caused your results.



If I had an ADC or Ariben's suggested optical cable (and equipment that could use an optical cable), I would certainly try both suggested methodologies, just to be fair, but I don't, so I cannot.

Further, with the only change in the system being the cables, I would suggest that logic dictates that the only cause of the results can be the variations in the cables themselves! 

There is a saying that 'I have seen the snow before'. I got into audio in the 1970s in North America. At that time the dominant (most read) magazine in stereo circles was _Stereo Review_. It was dominated by objectivists that said only measurements can count. Hence if an amp has very low measurable distortion, it therefore must sound the same as any other amp with similar low 'good' measurements. It was only when I took a  college course on audio engineering that I found out that this was not necessarily the case and while massive feedback, and other circuit tricks,  can make good for measurement, it can also make for a bad sounding amps.  Mags like _The Audio Amateur_ or even _Stereophile_ or _TAS_ existed then, but were very much out of the mainstream, so their calls that the objectivist view was false, was not really heard by most consumers. We now know that amps can and do sound very different and why measurement, at least in analogue, is only one perspective to understanding what is going on. Hence, I suggest that in digital this is also the case, and not-withstanding Shannon (1948) and everyone else, there is more to be learned in digital technology to provide enlightenment than we currently know and this includes the digital cables that stitches our digital systems together.


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## gregorio (Sep 23, 2017)

Duy Le said:


> [1]If the signal cannot be effected, why does cable manufacturer try to isolate electric line from signal line and many armors are applied?
> [2] I think more jitters can be produced on the worst cable than the good cable.
> [3] Do you mean the better cable should be used for the poorer quality DAC?



1. A DAC: Digital to Analogue Converter, must by definition have an analogue section and analogue audio most definitely can be affected by noise. Digital cannot be affected by noise, a 1 or a 0 is always just a 1 or a 0, a noisy or clean 1 or 0 does not exist in the binary world of digital data. The only point at which digital data can be affected by noise is when the noise is so severe that it effectively changes the values of the 1's and 0's but for that to happen requires a serious fault/flaw in the cable, source or DAC, a flaw which puts it outside the USB standards.

2. No it can't. If a cable is a USB cable, the signal must be within the USB specifications (otherwise it is not a USB cable). Likewise, a USB DAC has to be able to deal with a USB specification signal otherwise it is not a USB DAC..Therefore, it does not matter how much jitter there is in the signal, the DAC should perform flawlessly, providing it's not so much jitter as to be outside the USB specification. This of course is the whole point of a protocol such as USB, it means the manufacturer of any USB device does not need to know the specifics of every other individual device in order to communicate flawlessly with it, the manufacturer just assumes every other USB device will follow the USB specifications and therefore only has to engineer their device to operate flawlessly with a USB specification signal.

3. A "better" USB cable could only be better with a device which does not perform flawlessly with a USB specification signal, IE. A faulty DAC. If you do not have a faulty DAC then any cable which meets USB specifications will cause the DAC to perform perfectly and obviously, a "better" cable cannot cause a DAC to perform more than perfectly.

G


----------



## Triode User

gregorio said:


> 1. A DAC: Digital to Analogue Converter, must by definition have an analogue section and analogue audio most definitely can be affected by noise. Digital cannot be affected by noise, a 1 or a 0 is always just a 1 or a 0, a noisy or clean 1 or 0 does not exist in the binary world of digital data. The only point at which digital data can be affected by noise is when the noise is so severe that it effectively changes the values of the 1's and 0's but for that to happen requires a serious fault/flaw in the cable, source or DAC, a flaw which puts it outside the USB standards.
> 
> 2. No it can't. If a cable is a USB cable, the signal must be within the USB specifications (otherwise it is not a USB cable). Likewise, a USB DAC has to be able to deal with a USB specification signal otherwise it is not a USB DAC..Therefore, it does not matter how much jitter there is in the signal, the DAC should perform flawlessly, providing it's not so much jitter as to be outside the USB specification. This of course is the whole point of a protocol such as USB, it means the manufacturer of any USB device does not need to know the specifics of every other individual device in order to communicate flawlessly with it, the manufacturer just assumes every other USB device will follow the USB specifications and therefore only has to engineer their device to operate flawlessly with a USB specification signal.
> 
> ...



_"If you do not have a faulty DAC then any cable which meets USB specifications will cause the DAC to perform perfectly"_

Apart from issues caused by RF or other noise.


----------



## gregorio

Triode User said:


> _"If you do not have a faulty DAC then any cable which meets USB specifications will cause the DAC to perform perfectly"_
> Apart from issues caused by RF or other noise.



No!!! If a USB DAC is receiving a USB specification signal and is audibly affected by noise/interference then it is faulty. The only potential exception to this obvious rule could be in the case of an extreme environment. It seems to me that some audiophiles appear to be conditioned into a belief that an expensive consumer USB DAC should not perform perfectly as a USB DAC in a consumer environment and are then willing to spend further significant sums of money (on audiophile cables, USB regen/cleaning devices, etc) in order for it to operate as advertised. I'm baffled by this approach! If I'd bought a faulty DAC (or any other faulty product) I would demand it be fixed or my money refunded, the last thing I'd do is go and waste even more money on it. Do audiophiles approach everything they purchase in this way?

G


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## Clive101 (Sep 23, 2017)

Triode User said:


> Apart from issues caused by RF or other noise



Thought you had nailed the thread question, appears not..?

I guess that some USB cables are better with noise rejection than others unless we have all got faulty DACs...? as suggested by others on this thread..!

Edit Noise transfer is the problem as you suggest.


----------



## Triode User

Clive101 said:


> Thought you had nailed the thread question, appears not..?
> 
> I guess that some USB cables are better with noise rejection than others unless we have all got faulty DACs...? as suggested by others on this thread..!
> 
> Edit Noise transfer is the problem as you suggest.



Yep, it appears my DAC is faulty. Who would have thought it. I'll send it back on Monday. And the Blu2 because I won't have a use for that when the DAC goes back.


----------



## Duy Le

gregorio said:


> 3. A "better" USB cable could only be better with a device which does not perform flawlessly with a USB specification signal, IE. A faulty DAC. If you do not have a faulty DAC then any cable which meets USB specifications will cause the DAC to perform perfectly and obviously, a "better" cable cannot cause a DAC to perform more than perfectly.
> 
> G


I see it conflicts with your previous posts. You said that USB cable does not effect sound.


----------



## Clive101

http://hifipig.com/new-usb-cable-from-cad-at-indulgence/#more-34295

 It would seem noise can get transferred along the USB cable hence the a manufacture has tried to filter out the noise..?
See the above link


----------



## Arpiben

Clive101 said:


> Thought you had nailed the thread question, appears not..?
> 
> I guess that some USB cables are better with noise rejection than others unless we have all got faulty DACs...? as suggested by others on this thread..!
> 
> Edit Noise transfer is the problem as you suggest.



Again, I will remind that is not up to USB cable to filter noises created at Source ( Computer/DAP) or at DAC level.
Again the USB manufacturer is providing  very vague details dealing with which high frequencies its 'patented' cable is rejecting.
FPGA/USB MCU chips/ etc are generating EMI at their clock frequencies ( around 100MHz for example) and harmonics.
Properly filtered Ins&Outs will not require ferrite chokes on USB or for the more wealthy dedicated audiophile USB cable.

A properly designed DAP/DAC should take into account those well known issues.
For this reason we may consider those items faulty.


----------



## Clive101

Yes again I have a faulty DAC as others.
Noise from the source should not be present but it is to a greater or lesser extent depending on the source which is why some USB leads sound different as they deal with noise to greater or less extent depending on how they are made I guess.
The thread question is the main thing to consider not the DAC


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## Triode User

Clive101 said:


> Yes again I have a faulty DAC as others.
> Noise from the source should not be present but it is to a greater or lesser extent depending on the source which is why some USB leads sound different as they deal with noise to greater or less extent depending on how they are made I guess.
> The thread question is the main thing to consider not the DAC



Yeah, you and me with our faulty DACs! Funny that I don't give a flying fig. I'd much rather have my dac and some ferrites than any other dac I have come across.


----------



## Arpiben

Clive101 said:


> Yes again I have a faulty DAC as others.
> Noise from the source should not be present but it is to a greater or lesser extent depending on the source which is why some USB leads sound different as they deal with noise to greater or less extent depending on how they are made I guess.
> The thread question is the main thing to consider not the DAC



Unless you measure DAP/DAC digital/analog Outputs there is no way to characterise the eventual RFI/EMI.
Unless USB cable manufacturers provide patent reference or frequency range rejection there is no way to know if noises are at least reduced.
EMI/RFI may or may not be audible.
EMI/RFI may or may not create IMD Intermodulation in the audible range.
EMI/RFI may or may not significantly change/modulate Noise Floor.

At the end users are left with empirical or tatonnement procedures trying different ferrites or USB cables.

I am not judging your or anybody DAP/DAC. I only have mixed feelings when some manufacturers are suggesting to use ferrite chokes for interconnecting their own equipments...

Until USB cable manufacturers are showing tangible measurements the discussion will be useless.
Some will keep believing that '0' and '1' are altered, their choice.


----------



## Clive101

Arpiben said:


> Unless you measure DAP/DAC digital/analog Outputs there is no way to characterise the eventual RFI/EMI.
> Unless USB cable manufacturers provide patent reference or frequency range rejection there is no way to know if noises are at least reduced.
> EMI/RFI may or may not be audible.
> EMI/RFI may or may not create IMD Intermodulation in the audible range.
> ...



I am not technical so your post is a little wasted on me ( sorry ) however I do not believe the "0" and "1" are being altered by cheap or expensive cables ( if working correctly ).

What I am sure about is that different USB cables sound different with the same equipment, but I have found the difference to be smaller with the addition of a different source and the addition of a Tours Power supply.

The DAC should not be to correct noise although it would be nice, noise may come from the DAC as well but with Dave ( as this is the only one I have ) I think this is not possible if you look at the noise level spec.


----------



## Arpiben

Clive101 said:


> I am not technical so your post is a little wasted on me ( sorry ) however I do not believe the "0" and "1" are being altered by cheap or expensive cables ( if working correctly ).
> 
> What I am sure about is that different USB cables sound different with the same equipment, but I have found the difference to be smaller with the addition of a different source and the addition of a Tours Power supply.
> 
> The DAC should not be to correct noise although it would be nice, noise may come from the DAC as well but with Dave ( as this is the only one I have ) I think this is not possible if you look at the noise level spec.



If you are able to find differences one should be able to measure them.
Dealing with specifications, manufacturers are always providing those showing their strengths never their weaknesses.
On top of this, measurements are performed under the best possible environment.
Interoperability or interferences issues are not only found with audio equipment.


----------



## Clive101

Arpiben said:


> If you are able to find differences one should be able to measure them.
> Dealing with specifications, manufacturers are always providing those showing their strengths never their weaknesses.
> On top of this, measurements are performed under the best possible environment.
> Interoperability or interferences issues are not only found with audio equipment.



Yes measurements..! I have no tools to measure the difference apart from my ears (including the brain processing) simple but effective but not scientific as subjective but for me gets the job done.
The measurements of Dave are I believe the lowest for noise in the world for a DAC against one of the best machines to measure noise (read it somewhere).
"Under the best conditions" of course I would expect that its common practice for all products not only HiFi.


----------



## D2Girls

Sorry for the question but what exactly will the digital noise being carried over the USB cable sound like when a song is playing? Would this noise be the fault of the digital source or the cable?


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## theheadfier (Oct 3, 2017)

Why do USB cables make such a difference?

It's pretty simple, really.  *Because your brain tells you so.  *

There you have it.  No rocket science needed.

Now if you just bought an expensive "high-end" USB cable, and your brain tells you that it makes an improvement in the sound of your system, then good for you.  And good for the manufacturer, too.  The difference may be as real to you as it is imaginary to me, or vice versa, but isn't the point of buying audio equipment really is satisfying what our brain interprets as good sound?

But seriously now, if you read past this, I'll tell what I really think: 

Digital signals are transmitted as, guess what, "analog" waveforms, and as such the interpretation of 0s and 1s out of the discrete fluctuations of the waveforms are not error-free. 
Unlike the USB data connection used by computer peripherals such as external hard drives, printers, etc., USB audio unfortunately follows a rather *rudimentary transmission protocol* that does not have the sophisticated error corrections that PC data connections have. 
USB audio still uses the same old protocol used by the original digital audio products decades ago, you know when USB wasn't even invented yet.  
So that's why the high-end cables, which at different levels provide their solution to the transmission issues,* can make a difference* in sound quality.


----------



## Whazzzup

An external music server  running roon core has more impact than any usb, or isolator. So on the one hand the source of 1 and 0 are really important.


----------



## theorist

Whazzzup said:


> An external music server  running roon core has more impact than any usb, or isolator. So on the one hand the source of 1 and 0 are really important.


I agree, but having dropped several grand, if not more, on your Roon running music server, it makes sense to drop a bit more to replace the 'freebees' that comes with the server for both the power cord connecting it to the power supply and the digital cable (USB or other) connecting it to your DAC, provided you *believe* you hear a worthwhile improvement in musicality from your system having done so.


----------



## Whazzzup (Oct 3, 2017)

theorist said:


> I agree, but having dropped several grand, if not more, on your Roon running music server, it makes sense to drop a bit more to replace the 'freebees' that comes with the server for both the power cord connecting it to the power supply and the digital cable (USB or other) connecting it to your DAC, provided you *believe* you hear a worthwhile improvement in musicality from your system having done so.


 my unit comes with an odapi ps. It connects via USB audio quest diamond to chord TT HD USB port. The single biggest upgrade in sound is my streamer.  USB is more insurance something you pay for peice of mind less so functional improvement. So how those bits gets to your dac do matter. In what for what sq improvements is debatable.


----------



## theheadfier

I do believe USB cable makes a difference in sound quality.  However, I remember reading quite a few audio reviews of certain USB cables where the reviewer talks about how one USB cable gives bass more heft, or has better treble extension. Now that is just ridiculous. USB cable does not change sound quality in THAT way.  That's probably just the reviewer's brain playing tricks on him.


----------



## theorist

theheadfier said:


> I do believe USB cable makes a difference in sound quality.  However, I remember reading quite a few audio reviews of certain USB cables where the reviewer talks about how one USB cable gives bass more heft, or has better treble extension. Now that is just ridiculous. USB cable does not change sound quality in THAT way.  That's probably just the reviewer's brain playing tricks on him.



When I posted (#205) a blind test of USB cables on the this thread on Sept 17 (my time), I noted that the better cables allowed you to better perceive/separate out the different elements in the recording. Specifically on the musical sample being listened to, while the base notes structuring the musical presentation was there in the inexpensive generic USB cable, it did not stand out or particularly  appear to 'structure' the musical presentation, while with the more expensive dedicated USB cables, it certainly readily did so. It was not that the base had more heft, as such, rather that it had much more perceived presence and importance in the musical presentation.


----------



## Triode User

theorist said:


> When I posted (#205) a blind test of USB cables on the this thread on Sept 17 (my time), I noted that the better cables allowed you to better perceive/separate out the different elements in the recording. Specifically on the musical sample being listened to, while the base notes structuring the musical presentation was there in the inexpensive generic USB cable, it did not stand out or particularly  appear to 'structure' the musical presentation, while with the more expensive dedicated USB cables, it certainly readily did so. It was not that the base had more heft, as such, rather that it had much more perceived presence and importance in the musical presentation.



Again though, we have to be careful in possibly confusing analogue cable attributes and qualities to digital cables. 

It is possible that some digital cables act as filters and filter out RF and other noise. This noise (or its absence) can affect our perception of the music. This has nothing to do with the digital signal per se. 

Also, cables do not necessarily have to be expensive to sound good. As we are finding with the bnc cables between Blu2 and Dave some cheap ferrites can often fulfill the filter function.


----------



## Clive101

There are some interesting posts on the Dave thread which may shed some light on the USB cabling issue.

https://www.head-fi.org/threads/chord-electronics-dave.766517/page-613

One could deduct that noise not only comes through the source but through the cable as well, so perhaps different cables filter out the noise which makes the difference..?

Oh for the scientific people there is plenty of kit with measurements and video which helps.

In essence noise gets amplified in the amps and hence affects the music, zeros and ones not affected by the way.


----------



## Arpiben

Clive101 said:


> There are some interesting posts on the Dave thread which may shed some light on the USB cabling issue.
> 
> https://www.head-fi.org/threads/chord-electronics-dave.766517/page-613
> 
> ...


Hi Clive101,

People used to deal with EMI/RFI issues do not need at all such videos (wink+smile).

Cables can be tuned to be RF antennae.
You can tune your USB cable to receive FM radio frequencies and as such increase noise floor/ etc...Maybe some will like the result sound more (smile).

USB cable is not the only road/highway for EMI/RFI to reach your DACs/Amps/LS/Headphones ....

If your USB cable need to filter everything from 50Hz/60Hz (AC) up to 100MHz, at the end you will have no available data!


----------



## Clive101

Arpiben said:


> Hi Clive101,
> 
> People used to deal with EMI/RFI issues do not need at all such videos (wink+smile).
> 
> ...



Well made me smile but I am sure we all agree zeros and ones are not being changed and noise is an issue.

The burning question if we all agree the sound if different with different USB cables it must be noise that is affecting the sound. (on the same equipment with different USB cables ). Mind you some people my not have a noisy environment so another variable..?

If that is true surely each individual USB cable handles the noise if a different way because of shielding and perhaps secondly ( perhaps not ) some sort of filter ..?


----------



## gregorio

Clive101 said:


> [1] I am sure we all agree zeros and ones are not being changed and [2] noise is an issue.



1. If we are going to be even remotely logical/sensible about this, then we HAVE to agree this point. The alternative, that zeros and ones are being changed, must lead to the conclusion that the USB protocol does not/cannot work, that the perfect transfer of digital data is impossible and that the digital age does not and cannot exist, which of course would be patently ludicrous.

2. This is what I find bizarre. It would appear that some/many audiophiles do indeed agree/accept that noise is an issue but there's 2 problems with this: A. Audiophile DACs quote signal to noise ratios typically 100 to 1000 times greater than the signal to noise ratio which actually exists on pretty much any commercial recording. For this noise to be audible the manufacturers of these audiophile USB DACs must be lying massively about their signal to noise ratios. B. There are countless millions of non-audiophile DACs out there, pro-audio and mass produced consumer DACs, which do not suffer from noise. Take for example an iPhone, the component cost of DAC/amp/audio circuitry in an iPhone can't be more than about $20, those components are only an inch or so away from some pretty powerful EM/RF noise sources and yet there's no audible noise and, there are a number of pro-audio USB DACs (+ ADCs) costing less than $100 which are well enough designed to achieve their quoted noise floors (way below audibility) with any quality of USB signal/cable. Why do at least some audiophile DACs apparently fail to achieve these basics of electrical, EM/RF noise isolation and why do audiophiles appear to accept this? If I bought a car advertised as having say 400 hp, only to find out that it outputs much less horse power than a Ford Fiesta, unless I buy an expensive after-market accessory, I'd be demanding they automatically supply that accessory with the car or take the car back and give me a refund! So no, noise absolutely should not be an issue in ANY competently designed DAC and if a particular USB DAC requires a special/audiophile cable in order to operate optimally with any USB signal (and for any noise to be significantly below inaudibility) then it should be supplied with that cable in the first place!



Clive101 said:


> The burning question if we all agree the sound if different with different USB cables it must be noise that is affecting the sound.


 
I can agree that different USB cables could sound different, given the condition of a faulty/incompetently designed DAC, but this still doesn't solve our issue. As theheadfier pointed out, in anecdotal audiophile reviews/opinions of different USB cables what we see is flowery descriptions of bass heft, treble extension, better separation, etc. But little/no mention of noise! The are only two possible, sensible explanations for this: 1. The DAC being used is competently designed and any differences between USB cables exist only in the perception/biases of the listener, rather than in the actual audio being output being output by the DAC or 2. The DAC being used is incompetently designed (the power/grounding/interference is not adequately isolated from the DAC's components) and the resultant noise is mistakenly interpreted by the listeners' perception as a loss of bass heft, treble extension, separation, etc. In either case, listener perception/bias is playing a large (or entire) part in what they believe they are hearing! The alternative is the ludicrous/illogical belief that the zeros and ones ARE being changed by the audiophile cable and not just any random zeros and ones but very specific zeros and ones being changed to very specific values. For this to occur, the audiophile USB cable would need some sort of intelligence, software+processing capability or magic!

G


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## Clive101 (Oct 5, 2017)

gregorio said:


> 1. If we are going to be even remotely logical/sensible about this, then we HAVE to agree this point. The alternative, that zeros and ones are being changed, must lead to the conclusion that the USB protocol does not/cannot work, that the perfect transfer of digital data is impossible and that the digital age does not and cannot exist, which of course would be patently ludicrous.
> 
> 2. This is what I find bizarre. It would appear that some/many audiophiles do indeed agree/accept that noise is an issue but there's 2 problems with this: A. Audiophile DACs quote signal to noise ratios typically 100 to 1000 times greater than the signal to noise ratio which actually exists on pretty much any commercial recording. For this noise to be audible the manufacturers of these audiophile USB DACs must be lying massively about their signal to noise ratios. B. There are countless millions of non-audiophile DACs out there, pro-audio and mass produced consumer DACs, which do not suffer from noise. Take for example an iPhone, the component cost of DAC/amp/audio circuitry in an iPhone can't be more than about $20, those components are only an inch or so away from some pretty powerful EM/RF noise sources and yet there's no audible noise and, there are a number of pro-audio USB DACs (+ ADCs) costing less than $100 which are well enough designed to achieve their quoted noise floors (way below audibility) with any quality of USB signal/cable. Why do at least some audiophile DACs apparently fail to achieve these basics of electrical, EM/RF noise isolation and why do audiophiles appear to accept this? If I bought a car advertised as having say 400 hp, only to find out that it outputs much less horse power than a Ford Fiesta, unless I buy an expensive after-market accessory, I'd be demanding they automatically supply that accessory with the car or take the car back and give me a refund! So no, noise absolutely should not be an issue in ANY competently designed DAC and if a particular USB DAC requires a special/audiophile cable in order to operate optimally with any USB signal (and for any noise to be significantly below inaudibility) then it should be supplied with that cable in the first place!
> 
> ...



Well at least we agree the zeros and ones are not being changed.

Well an IPhone compared to the DACs we all use on the forum are a little different. Firstly we all use mains power ( well most IPhones I see are plugged in charging most of the time but that's a different issue ) and secondly the iPhone DAC may not produce a sound capable to show a difference with or without noise ( but I see you point ).

I have no doubt that all our DACs are not faulty and are working correctly.

When I connect my Torus Power supply the difference in the USB cables are closer which would seem to suggest noise and USB cable interaction ( as the cable is the other variable ).

If the DAC does not filter out noise do you suggest the DAC is faulty or the source of the noise...? Which may suggest why you think DACs may be faulty, I suppose it would be nice if they did filter out noise. If the DAC produces a lot of noise then I guess the DAC is to blame but in my case the Dave is a constant.

When the noise is reduced I get a clean sound no boom in the bass and no sharp treble.

I have no doubt as to noise entering though the mains and or into the USB cable ( poor shielding ) then into the DAC and being amplified on the analogue section and messing up the sound in someway.

Edit It could also be noise coming from the source ie server, laptop etc


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## gregorio

Clive101 said:


> [1] Well at least we agree the zeros and ones are not being changed.
> [2] Well an IPhone compared to the DACs we all use on the forum are a little different. Firstly we all use mains power ( well most IPhones I see are plugged in charging most of the time but that's a different issue ) and [2a] secondly the iPhone DAC may not produce a sound capable to show a difference with or without noise ( but I see you point ).
> [3] When I connect my Torus Power supply the difference in the USB cables are closer which would seem to suggest noise and USB cable interaction ( as the cable is the other variable ).
> [4] If the DAC does not filter out noise do you suggest the DAC is faulty or the source of the noise...? Which may suggest why you think DACs may be faulty ...
> ...



1. Yes indeed. However, specific ones and zeros being changed in a specific manner is the only explanation which could account for many of differences typically described between USB cables. Unless of course those differences are not actually in the sound output but only in the listeners' perception.

2. It's not a different issue, it's all part of the same issue. Why would using mains power be different from using battery power? Yes, I've heard some audiophile explanations for why but those explanations are nonsense. Somehow, many audiophiles seem to have been convinced that handling mains power adequately is near impossible. This is simply untrue! It's untrue not just because science says so, it's untrue because competent electrical engineers say so and because there are a whole range of audio products, which have been on the market for many years, that actually demonstrate/prove this fact!
2a. Nope, iPhones have a very clean and linear output. The only potential drawback of iPhones is that they're not designed to power many of the bigger full size headphones.

3. Yes, I entirely agree! However, that observation misses the real point/question, which is: Why should a mains power supply and any USB cable interaction have any effect whatsoever on the output of a device advertised as a mains powered USB DAC? ...

4. I wouldn't put it quite that way but essentially yes, that's my position. I wouldn't put it that way because it's not really a question of a DAC actively filtering out noise, it's simply a question of competent design. The design of power supply handling, USB signal handling, grounding and isolation if done competently eliminates the possibility of noise anywhere near audibility getting through to a DAC's output. This brings us back to point #2 and how difficult it is to achieve this "competent design" or rather, how is it that many audiophiles seem to have been convinced that it's very difficult or virtually impossible? And, that DACs which do not achieve this level of competency are acceptable and furthermore, that it's then somehow acceptable to spend hundreds/thousands of dollars on USB purifiers, audiophile grade cables, audiophile grade power cables and power conditioners to cure the problems that any competent DAC design should have already eliminated.
4a. Case in point! If mains power is causing audible noise in your DAC's output, your DAC is either broken or has been incompetently designed. Likewise, if you need more shielding than is provided by a standard USB cable, it's because the isolation in your DAC is faulty or has been incompetently designed! So how difficult is this "competent design" really? Sure, at one time it was near impossible, then later it became possible but at a high price but today it's trivial, cheap and completely standard and expected ... except apparently in a segment of the audiophile world! If I bought a pro-audio DAC, advertised as mains powered, I would expect it to work optimally with mains power. If it didn't, if it required conditioned power to perform optimally (if conditioned power improved the output massively enough to be an audible improvement) I'd be straight on the phone asking for a replacement non-faulty unit or my money back if all their units are similarly faulty and, if it were the latter, I'd then be on the pro-audio forums warning others that it's a pile of junk to be avoided! Likewise with USB, if it required an audiophile USB cable and/or "purifier" to isolate from any audible USB power, computer or EM/RF noise, rather than the no brand USB cable it was probably supplied with. Just to be clear, I'm not talking about multi-thousand dollar pro-audio DACs, I'm talking about cheap $100 or so units, which have far higher component costs than audiophile DACs because they are also ADCs, include mic pre-amplifiers and have balanced and unbalanced outputs! So why can some/many audiophile DAC manufacturers apparently not achieve the level of competency achieved by pro-audio manufacturers for years, at a fraction of the price and which the pro audio community takes for granted? And why do many in the audiophile community apparently have such vastly different expectations of "competent design"? Ultimately the answer comes down to marketing, the desire/need of audiophile manufacturers to avoid the standard, proven solutions and attempt exotic designs which provide marketing opportunities/implications but fail to solve the already solved issues of isolation, power handling, etc.
4b. Another case in point. Any competently designed DAC should be isolated from server/laptop/source noise. Isn't the whole point of an external DAC to isolate from computer noise? All computers, servers and laptops produce significant noise, isn't your DAC designed to be connected to a standard computer, laptop or server? Can it only perform optimally with silent computers, servers or laptops, which don't actually exist in the real world? How is such a DAC not faulty or incompetently designed?

G


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## Clive101

Thank you for the detailed reply and I sort of now see where your coming from ( an ideal world ) and if I may say I sort of agree on most of what you say ...! Surprisingly

Your talking about an idea theoretical world, I guess by the tone of your post...? If you think the ideal DAC should be immune from noise from computers servers I with you on that but unfortunately it is not the case, the designer of Dave has gone a long way to do exactly this, according to his posts at HeadFi and in the feed back by people using Dave. My experience is with better power supply and server the Sound Quality was cleaner, USB cables changed to a greater extent without the Power supply and server but perhaps I have more noise than others ..!

I suppose in the future we will see DACs and Servers immune to noise but for the moment I have yet to find one.



gregorio said:


> 2a. Nope, iPhones have a very clean and linear output. The only potential drawback of iPhones is that they're not designed to power many of the bigger full size headphones.


Well this may be the case but I very much doubt that the iPhone can compete with Dave if the iPhone was connected to an amplifier but that's a different issue perhaps a different thread..?



gregorio said:


> Why would using mains power be different from using battery power?


You can get a bad electrical shock from mains electric. ( see my tech knowledge is not that great )


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## oldthor

Take two of the same cables and price one at 150 dollars and I'll bet  the experts will find better sound out of the more expensive of the two. I've long suspected that most buyers would NEVER admit being duped into paying some of the outragious prices I've seen being offered for superior sounding USB cables. makes as much sense to me as tying a knot in your USB cable to slow down the ones' and zeros so they don't crash into each other or running your cable uphill.I imagine that with proper high end monitoring equipment you could see something, maybe better noise isolation because of better shielding but I doubt there is any real difference you can actually hear


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## gregorio

Clive101 said:


> [1] Your talking about an idea theoretical world, I guess by the tone of your post...? If you think the ideal DAC should be immune from noise from computers servers I with you on that but unfortunately it is not the case ... [1a] the designer of Dave has gone a long way to do exactly this ...
> [2] You can get a bad electrical shock from mains electric. ( see my tech knowledge is not that great )



1. Ah but it is the case! I'm not talking about an ideal theoretical world, I'm talking about the real world of actual products which have been on the market for years and achieve exactly that level of immunity as standard and for peanuts! Again, ANY pro-audio DAC (ADC/DAC) which did not achieve that level of immunity would be instantly slammed/shunned by the pro audio community and for that reason no manufacturer would even bother releasing a DAC to the pro audio community which doesn't achieve that level of immunity.
1a. But apparently, from what you describe, the "long way" you mention is not nearly as long a way as pro audio DAC manufacturers achieved years ago and for a tiny fraction of the price! How come you believe that this "long way" to achieving audible immunity really is a long way and that actual audible immunity is only some sort of "ideal theoretical" concept, rather than an already solved issue in practise, to the point of it being a standard expectation even in very cheap pro audio units? Maybe there's another explanation but the one that jumps out at me is audiophile marketing.

2. We can look at this issue the other way around. If the use of mains power really is so unsolvably problematic but these problems don't exist with battery power, then why don't audiophile DAC manufacturers simply put a battery in their DACs? Buffer the mains power through a battery and hey presto all the problems vanish! Likewise with your power conditioner, if a DAC performs so much better with conditioned power then why doesn't the manufacturer simply put that power conditioning circuitry in their DAC in the first place, the trade price for that circuitry is peanuts?! That's effectively what pro audio ADC/DACs do and hence why feeding conditioned power to such a DAC does not make any difference.

G


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## Triode User

gregorio said:


> 2. We can look at this issue the other way around. If the use of mains power really is so unsolvably problematic but these problems don't exist with battery power, then why don't audiophile DAC manufacturers simply put a battery in their DACs?



It's called a Hugo.


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## Triode User

gregorio said:


> 1. Ah but it is the case! I'm not talking about an ideal theoretical world, I'm talking about the real world of actual products which have been on the market for years and achieve exactly that level of immunity as standard and for peanuts! Again, ANY pro-audio DAC (ADC/DAC) which did not achieve that level of immunity would be instantly slammed/shunned by the pro audio community and for that reason no manufacturer would even bother releasing a DAC to the pro audio community which doesn't achieve that level of immunity.
> 1a. But apparently, from what you describe, the "long way" you mention is not nearly as long a way as pro audio DAC manufacturers achieved years ago and for a tiny fraction of the price! How come you believe that this "long way" to achieving audible immunity really is a long way and that actual audible immunity is only some sort of "ideal theoretical" concept, rather than an already solved issue in practise, to the point of it being a standard expectation even in very cheap pro audio units? Maybe there's another explanation but the one that jumps out at me is audiophile marketing.
> 
> 2. We can look at this issue the other way around. If the use of mains power really is so unsolvably problematic but these problems don't exist with battery power, then why don't audiophile DAC manufacturers simply put a battery in their DACs? Buffer the mains power through a battery and hey presto all the problems vanish! Likewise with your power conditioner, if a DAC performs so much better with conditioned power then why doesn't the manufacturer simply put that power conditioning circuitry in their DAC in the first place, the trade price for that circuitry is peanuts?! That's effectively what pro audio ADC/DACs do and hence why feeding conditioned power to such a DAC does not make any difference.
> ...



I am not familiar with these pro audio dacs and I would find it easier to understand the differences between pro audio and consumer if you could give some examples of typical Pro Audio DACs?


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## gregorio (Oct 6, 2017)

Triode User said:


> I am not familiar with these pro audio dacs and I would find it easier to understand the differences between pro audio and consumer if you could give some examples of typical Pro Audio DACs?



A typical DAC used in commercial studios would be the AVID HD I/O or the Apogee Symphony. However, these are typical big ADC/DAC units with 16/32 ins and outs, all the bells and whistles, price tags well into the 4 figures and not really applicable to audiophiles. However, there is a large range of pro audio ADC/DACs which are designed for musicians and smaller project studios, fewer ins and outs and great value for money. A typical one would be the (apparently) best selling USB audio interface in the world, the Focurite Scarlett but surprisingly competently designed for the price is the Behringer UMC204HD, actually it's performance is almost shocking considering the quality of conversion and the amount of functionality you get for just $80.

G


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## theorist

gregorio said:


> All computers, servers and laptops produce significant noise



Some interesting points raised on both sides of the debate in the last day or so. Perhaps one 'component' of this debate , since Gregorio agrees that USB inputs of DACs need to address noisy data sources in the digital reproduction of recordings is the standards to which this issue has to be addressed. Perhaps a certain amount of noise and the impact that it has on the latter data chain can be pragmatically  ignored (hence it is not even 'heard') in a professional studio environment as it has no significant eventual impact on, or is not even retained, in  the finished digital product  -- the recording -- while for audiofiles and their interests in the actual immediate reproduced very detailed sound of the performance (live or 'created' in and by the studio) created by this data stream in real time, playing back the clean studio recording, the impact of this in-home computer/server noise on the downstream reproduction system equipment (analogue output circuit of the DAC, HP amp, etc) is much more important.


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## gregorio

theorist said:


> [1] Perhaps a certain amount of noise and the impact that it has on the latter data chain can be pragmatically  ignored (hence it is not even 'heard') in a professional studio environment as it has no significant eventual impact on, or is not even retained, in  the finished digital product  -- the recording -- [2] while for audiofiles and their interests in the actual immediate reproduced very detailed sound of the performance (live or 'created' in and by the studio) created by this data stream in real time, playing back the clean studio recording, the impact of this in-home computer/server noise on the downstream reproduction system equipment (analogue output circuit of the DAC, HP amp, etc) is much more important.



1. I'm not sure I understand exactly what you're saying/asking. Noise is certainly not something that can be "pragmatically ignored" and can/does have a significant impact in the finished product but it depends on where in the chain we're talking about. In the analogue days, even with no signal, just having an open channel on an analogue mixing desk would add noise, each processor employed (such as EQs, compressors, etc.) on each of those channels added it's own noise and sub-mixing and bouncing added still more noise. Admittedly we're talking very small amounts of noise with top of the line analogue mixing equipment but it's cumulative and typically we were dealing with 24 channels + sub-mix channels and at least one or more processors on each of those channels. Today's 64bit digital mixing environments means that all those sources of noise present in analogue mixing, even the cumulative noise from many hundreds of channels with multiple processors on each, is maintained way below what any reproduction system could resolve (even in theory) and way below audibility. So yes, today we can effectively ignore this source of noise, which is virtually the opposite to the days of analogue mixing, when noise from the mixing process was often the most significant noise in the entire chain and a constant worry/battle. However, before we can start mixing, we obviously have to record something to mix and that means dealing with acoustic noise, the noise floor which exists in every environment (studio live room, concert venue, etc.) and analogue noise from the equipment before we enter the digital realm (microphones and mic pre-amps) and this noise we do have to concern ourselves with. While we're getting insignificant "self" noise from the digital processing itself, the recorded acoustic and analogue noise is ever present throughout the rest of the production chain and completely dwarfs (by a factor of at least 100) any noise from the conversion of the digital data, by our DACs, for monitoring. So we are very mindful of noise, even during mixing because many of the mixing processes will exacerbate that recorded acoustic and analogue noise.

2. No, not even close, in fact almost the exact opposite of what you're suggesting! I know that what you're suggesting forms the basis of most/much audiophile marketing and is the firmly held belief of many audiophiles themselves but in reality it's nonsense. As implied in the point above, professionally we're very carefully considering and prioritising the sources of noise, the areas and parts of the entire chain (from performer to listener) where the most significant noise occurs/exists and spending our money according to those priorities. This is typically NOT the case in the audiophile world, in fact audiophiles often do the exact opposite, spend very significant sums of money dealing with the least significant issues and sources of noise, while spending very little or completely ignoring the most significant! If we're talking about high fidelity reproduction in it's true sense, then the priority is noise floor and acoustic response of the listening/monitoring environment, then comes the positioning of the transducers (speakers) within that environment, then comes the transducers themselves and their amplification and then there's a very large gap to the DAC, so big a gap that the differences between modern pro audio DACs is completely insignificant in all but the finest monitoring environments and even then, the differences between very cheap and most expensive are relatively tiny. Differences between USB cables, power cables and other types of cables do not even figure on this list because we're assuming competently designed DACs and other equipment and therefore no differences even vaguely close to audible in even the best monitoring environments. The end result of all this is pretty much the opposite of what you appear to be suggesting, we are hearing details significantly more accurately than any audiophile system is capable of, details which few, if any, audiophiles are even consciously aware exist and we're not just hearing those details but actively working/processing/manipulating them!

G


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## Clive101 (Oct 7, 2017)

gregorio said:


> 1. Ah but it is the case! I'm not talking about an ideal theoretical world, I'm talking about the real world of actual products which have been on the market for years and achieve exactly that level of immunity as standard and for peanuts! Again, ANY pro-audio DAC (ADC/DAC) which did not achieve that level of immunity would be instantly slammed/shunned by the pro audio community and for that reason no manufacturer would even bother releasing a DAC to the pro audio community which doesn't achieve that level of immunity.
> 1a. But apparently, from what you describe, the "long way" you mention is not nearly as long a way as pro audio DAC manufacturers achieved years ago and for a tiny fraction of the price! How come you believe that this "long way" to achieving audible immunity really is a long way and that actual audible immunity is only some sort of "ideal theoretical" concept, rather than an already solved issue in practise, to the point of it being a standard expectation even in very cheap pro audio units? Maybe there's another explanation but the one that jumps out at me is audiophile marketing.
> 
> 2. We can look at this issue the other way around. If the use of mains power really is so unsolvably problematic but these problems don't exist with battery power, then why don't audiophile DAC manufacturers simply put a battery in their DACs? Buffer the mains power through a battery and hey presto all the problems vanish! Likewise with your power conditioner, if a DAC performs so much better with conditioned power then why doesn't the manufacturer simply put that power conditioning circuitry in their DAC in the first place, the trade price for that circuitry is peanuts?! That's effectively what pro audio ADC/DACs do and hence why feeding conditioned power to such a DAC does not make any difference.



So we disagree.
Dave used at Metropolis Studios so they have that wrong ..?  Noise does exist in studios  http://www.toruspower.com/torus-power-videos/ oh yes it does. Never seen a battery power source for HiFi although the Hugo TT is battery powered, I had one, still noise got though it from the source and USB cable which makes the battery no use at all, apart from the DAC it's self. Again a faulty DAC..! ( Dave responded better than Hugo TT but on mains )
http://www.toruspower.com/gallery/p...os-into-showrooms-with-help-from-torus-power/



theorist said:


> Some interesting points raised on both sides of the debate in the last day or so. Perhaps one 'component' of this debate , since Gregorio agrees that USB inputs of DACs need to address noisy data sources in the digital reproduction of recordings is the standards to which this issue has to be addressed. Perhaps a certain amount of noise and the impact that it has on the latter data chain can be pragmatically ignored (hence it is not even 'heard') in a professional studio environment as it has no significant eventual impact on, or is not even retained, in the finished digital product -- the recording -- while for audiofiles and their interests in the actual immediate reproduced very detailed sound of the performance (live or 'created' in and by the studio) created by this data stream in real time, playing back the clean studio recording, the impact of this in-home computer/server noise on the downstream reproduction system equipment (analogue output circuit of the DAC, HP amp, etc) is much more important.



Interesting had the same theory "Audio Studio" people listen in a different way and for different reasons..? I have a very long and detailed discussion with high end manufacture that make monitors for studio and consumer use, long story short same speakers tweaked for different reasons, end story the studio grade and consumer grade sound different. Then went onto cables Studio Grade for my system £200.00 Consumer Grade £16,000.00. Both Studio and Consumer departments of the company were correct, which left me quite puzzled..!

I wanted to purchase the studio equipment as thought it would be best after all it's what the professionals use and cheaper and with the £200.00 cables music to my ears ( no pun intended ) but it lead to the above conversation demo etc.

Consumer product did sound better to my ear.

So perhaps Studio People listen for a different sound..?


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## gregorio

Clive101 said:


> [1] Dave used at Metropolis Studios so they have that wrong ..?  [2] Noise does exist in studios  http://www.toruspower.com/torus-power-videos/ oh yes it does.



I don't believe you thought through your response very carefully!

1. You're joking right? Are you really saying that Metropolis studios do all their tracking and mixing on headphones (through a Dave) and don't use studio monitors? I don't doubt that Metropolis have the odd bit of consumer hifi equipment which is occasionally used for reference purposes, most decent studios do. I have some Senn HD650s for exactly the same reason but all my work is done on my studio monitors and I plug in the HD650s at the end, just to quickly check that typical higher end consumer cans are not doing anything too unexpected to my mix.

2. Again, you seem to have missed the point. I too have UPS/Conditioner in my studio and so do pretty much all the commercial studios I've worked in but it's to protect against lost work from a total power cut or brown out, it's got nothing to do with noise!



Clive101 said:


> Never seen a battery power source for HiFi although the Hugo TT is battery powered ...



You seem to be missing the point again. I'm not suggesting that a battery actually be used, there's better ways to achieve that end result without actually using a battery. I was just using that example to demonstrate some simple logic regarding the audiophile claims/marketing; that mains power issues are unsolvable but battery power doesn't suffer those issues.



Clive101 said:


> Consumer product did sound better to my ear. ... So perhaps Studio People listen for a different sound..?



Yes, us "studio people" are listening for a different sound compared to many/most audiophiles! The sound we're after is the highest fidelity attainable but that's NOT what the vast majority of audiophiles are after. If that sounds strange it's because many audiophiles don't really understand what the term "hifi" means, which is largely due to deliberate audiophile marketing practises. The term "HiFi" is typically used in the audiophile world to mean an expensive bit of audio kit which sounds good but the word "fidelity" actually means faithfulness. Therefore, a "high fidelity" reproduction system is a system which very accurately/faithfully reproduces a input signal ... and whether or not a system or piece of equipment "sounds better to your ear" is irrelevant, as is it's price!

Over the years I've had a number of audiophiles in my various studios, a few of them hardcore audiophiles with over 6 figure systems. A summary of their collective impressions would be something along the lines of: "Yes, quite impressive but far too clinical/analytical, I prefer my system". Although typically they'd have a slightly troubled expression while delivering that verdict! In reality, descriptions such as too clinical or analytical are effectively meaningless, my various studios have been very accurate/high fidelity and therefore have a faithful amount of "clinical" or "analytical". What they're really saying is that they are used to/prefer a system with a less faithful amount of "clinicality", a less accurate/lower fidelity system, although of course they'd never put it that way because they're totally convinced they own a "hifi" system. I want to make it clear that I'm not making any judgement about this fact, many people for example like a bit more bass, there's nothing at all wrong with that preference, but of course that's lower fidelity (less faithful) reproduction, not higher fidelity just because they like it better with additional bass!

G


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## theorist

gregorio said:


> If we're talking about high fidelity reproduction in it's true sense, then the priority is noise floor and acoustic response of the listening/monitoring environment, then comes the positioning of the transducers (speakers) within that environment



Thanks Gregorio for your detailed and, as always, very informative post. I do note however that I only listen to music at home with HPs, so perhaps in doing so I am largely negating this area you identify at most in need of adequate audiophile address.



Clive101 said:


> So perhaps Studio People listen for a different sound..?



As Gregorio actually implies in his post. He is listening as a skilled crafts-person/engineer to produce the best finished product that he can -- for the needs of his client -- so he is paying great attention to all the details, even those that may be below our noise floor. We, on the other hand, have the luxury to simply listen to music for our enjoyment and pleasure, so indeed, we may not necessarily be seeking the same sound, particularly if, as audiophiles, we are listening for particular aspects in our music, such as lots of dynamic range, that that vast majority of the listening market, ie MP3 streaming listeners or in-car listeners, actually don't want -- as Gregorio pointed out in a prior post -- hence the need for compression as well as other production effects wanted by the non-audiophile listener incorporated in many recordings.

I look forward to both your responses, in these regards.


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## Clive101

gregorio said:


> I don't believe you thought through your response very carefully!
> 
> 1. You're joking right? Are you really saying that Metropolis studios do all their tracking and mixing on headphones (through a Dave) and don't use studio monitors? I don't doubt that Metropolis have the odd bit of consumer hifi equipment which is occasionally used for reference purposes, most decent studios do. I have some Senn HD650s for exactly the same reason but all my work is done on my studio monitors and I plug in the HD650s at the end, just to quickly check that typical higher end consumer cans are not doing anything too unexpected to my mix.
> 
> ...



No Joking and well thought through.
1. I was Told Dave was used, I assumed it was to play music what Dave was designed for.
2. Tours power supply was used in a Studio for noise read the link, if you have no issue with noise good. ( Note Torus is not a UPS and hence used for noise only )



gregorio said:


> You seem to be missing the point again. I'm not suggesting that a battery actually be used, there's better ways to achieve that end result without actually using a battery. I was just using that example to demonstrate some simple logic regarding the audiophile claims/marketing; that mains power issues are unsolvable but battery power doesn't suffer those issues.



Well that was the point I was making.!



gregorio said:


> Yes, us "studio people" are listening for a different sound compared to many/most audiophiles! The sound we're after is the highest fidelity attainable but that's NOT what the vast majority of audiophiles are after. If that sounds strange it's because many audiophiles don't really understand what the term "hifi" means, which is largely due to deliberate audiophile marketing practises. The term "HiFi" is typically used in the audiophile world to mean an expensive bit of audio kit which sounds good but the word "fidelity" actually means faithfulness. Therefore, a "high fidelity" reproduction system is a system which very accurately/faithfully reproduces a input signal ... and whether or not a system or piece of equipment "sounds better to your ear" is irrelevant, as is it's price!
> 
> Over the years I've had a number of audiophiles in my various studios, a few of them hardcore audiophiles with over 6 figure systems. A summary of their collective impressions would be something along the lines of: "Yes, quite impressive but far too clinical/analytical, I prefer my system". Although typically they'd have a slightly troubled expression while delivering that verdict! In reality, descriptions such as too clinical or analytical are effectively meaningless, my various studios have been very accurate/high fidelity and therefore have a faithful amount of "clinical" or "analytical". What they're really saying is that they are used to/prefer a system with a less faithful amount of "clinicality", a less accurate/lower fidelity system, although of course they'd never put it that way because they're totally convinced they own a "hifi" system. I want to make it clear that I'm not making any judgement about this fact, many people for example like a bit more bass, there's nothing at all wrong with that preference, but of course that's lower fidelity (less faithful) reproduction, not higher fidelity just because they like it better with additional bass!





theorist said:


> As Gregorio actually implies in his post. He is listening as a skilled crafts-person/engineer to produce the best finished product that he can -- for the needs of his client -- so he is paying great attention to all the details, even those that may be below our noise floor. We, on the other hand, have the luxury to simply listen to music for our enjoyment and pleasure, so indeed, we may not necessarily be seeking the same sound, particularly if, as audiophiles, we are listening for particular aspects in our music, such as lots of dynamic range, that that vast majority of the listening market, ie MP3 streaming listeners or in-car listeners, actually don't want -- as Gregorio pointed out in a prior post -- hence the need for compression as well as other production effects wanted by the non-audiophile listener incorporated in many recordings.
> 
> I look forward to both your responses, in these regards.




The goal, One word    "Transparency" .


----------



## gregorio

Clive101 said:


> No Joking and well thought through.
> 1. I was Told Dave was used, I assumed it was to play music what Dave was designed for.
> 2. Tours power supply was used in a Studio for noise read the link, if you have no issue with noise good. ( Note Torus is not a UPS and hence used for noise only )
> 3. The goal, One word "Transparency" .



1. I'm sure a Dave is used on occasion, for the purpose I described. Another example of this sort of thing (reference use) would be the Auratone speaker. The Auratone was a truly horrendous speaker, hence why we affectionately called them horror-tones and at one time most commercial studios had one, for reference purposes. Auratone advertised them as being used by many/most of the top recording studios but of course they didn't mention that we only used them for reference purposes precisely because they were so bad! Over a decade ago they updated it and improved the design, so we all stopped using them! I'm not saying the Dave is equally as horrendous, just pointing out that being told something is used by a top studio (and the term "reference") does not necessarily mean what you think it means, it could mean anything, from world class to the absolute opposite!

2. I did read the link, did you? The whole thing is of course marketing but you seemed to have missed this:
"_The studio included a 16-channel Neve 5088 console, a Burl Mothership, Lynx Aurora, and a substantial amount of outboard equipment, all running on a 20 amp circuit that came dangerously close to overloading on a regular basis. In addition, the studio experienced a lot of noise on the power lines, resulting in less than optimal sound quality for recordings. Kelm recommended a Torus Power AVR-45, Toroidal Isolation power transformer with automatic voltage regulation to protect equipment against voltage sags, brownouts, and surges._"
I assume that you don't know what a Neve console is or how it worked? The Neve consoles (along with one or two others, such as SSL) were really the epitome of analogue mixing desk design but they had very demanding power supply requirements and came with a massive power supply unit which had to be located in another room. You had to turn them on and let them warm up for half an hour or more before you could use the desk and many studios never turned them off for that reason. This is all a completely different scenario from the relatively minuscule power requirements of a consumer DAC!

3. Yes, and an interesting word it is, considering how it's often misused in the audiophile world! ...



theorist said:


> I do note however that I only listen to music at home with HPs, so perhaps in doing so I am largely negating this area you identify at most in need of adequate audiophile address.



Yes, the substantial reduction of environmental listening noise and acoustic issues is of course the great advantage of HPs, but along with that great advantage comes a great disadvantage! I went to considerable lengths to explain what "fidelity" means in my last post and even in the post you quoted, I chose my words carefully when I said "_high fidelity reproduction in it's true sense_". In it's true sense, HPs are incapable of high fidelity reproduction! Virtually all commercial music is mixed and mastered on speakers (studio monitors) and obviously therefore in the presence of room acoustics. HPs have little/no room acoustics interaction and are therefore not being "faithful" (do not have high fidelity) in their reproduction of what was intended. The only time when HPs could be high fidelity is when reproducing a mix/master specifically made for headphones (such as a binaural recording for example) but those are few and far between. Again, I'm not talking about preference here but about fidelity. I know that some/many prefer the exaggerated soundstage and other consequences of headphone presentation and that's absolutely fine but an exaggerated soundstage is exaggerated, not a faithful, transparent, accurate or therefore high fidelity reproduction. There have been moves to compensate for this, the development of HRTFs for example but it's not quite there yet IMO and the take up of the technology hasn't been great and maybe it never will be, especially among those who prefer traditional HP presentation.



theorist said:


> ... we may not necessarily be seeking the same sound, particularly if, as audiophiles, we are listening for particular aspects in our music, such as lots of dynamic range, that that vast majority of the listening market, ie MP3 streaming listeners or in-car listeners, actually don't want -- as Gregorio pointed out in a prior post -- hence the need for compression as well as other production effects wanted by the non-audiophile listener incorporated in many recordings.



Although true within a certain context, there's rather more to it, as is often the case with music/audio, due to the advances in technology and the billions per year up for grabs for those who employ it artistically. While compression is certainly used (and sometimes abused) for the purpose you are quoting, in the 1960's it started being used as an artistic transient sculpting tool. Without going into too much detail and too far off topic, you absolutely do want compression! For example the sound of the rock kit by the 1970s is quite different to what a drum kit really sounds like and the use compression as a sculpting tool is largely responsible for that. Pretty much all modern popular music genres rely on compression to a significant extent and would not exist as they do without it.

G


----------



## theorist

gregorio said:


> Virtually all commercial music is mixed and mastered on speakers (studio monitors) and obviously therefore in the presence of room acoustics. HPs have little/no room acoustics interaction and are therefore not being "faithful" (do not have high fidelity) in their reproduction of what was intended.



Thanks as always for the insightful knowledge you impart in your posts! Agree with your comments about the limitations of HPs and the compromises that go with them, but they can still provide a very hi-quality playback, perhaps sound stage imagining aside, for relatively small expenditure, at least compared to 5 or 6 figure amps/speaker stereo systems. Not to mention, much more easily accommodating the 'spousal-turn-down-that-noise-factor'.

While you undoubtedly strive for the highest fidelity in your recordings -- thank you -- is this really the case for all studio recordings? Even if mixing is no longer done on the ubiquitous Yamaha NS10 (showing my age here), a lot of mixing still appears to be being done based on near-field monitoring and with a core concern for translation so as to sound as good as possible on mass-market playback platforms, with a resultant reduction in "_high fidelity reproduction in it's true sense_".


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## Clive101 (Oct 9, 2017)

gregorio said:


> 1. I'm sure a Dave is used on occasion, for the purpose I described. Another example of this sort of thing (reference use) would be the Auratone speaker. The Auratone was a truly horrendous speaker, hence why we affectionately called them horror-tones and at one time most commercial studios had one, for reference purposes. Auratone advertised them as being used by many/most of the top recording studios but of course they didn't mention that we only used them for reference purposes precisely because they were so bad! Over a decade ago they updated it and improved the design, so we all stopped using them! I'm not saying the Dave is equally as horrendous, just pointing out that being told something is used by a top studio (and the term "reference") does not necessarily mean what you think it means, it could mean anything, from world class to the absolute opposite!



Yes I assumed this from the start, I assumed you would as you are used to Studio practices more so than me, but at least we agree.



gregorio said:


> 2. I did read the link, did you? The whole thing is of course marketing but you seemed to have missed this:
> "_The studio included a 16-channel Neve 5088 console, a Burl Mothership, Lynx Aurora, and a substantial amount of outboard equipment, all running on a 20 amp circuit that came dangerously close to overloading on a regular basis. In addition, the studio experienced a lot of noise on the power lines, resulting in less than optimal sound quality for recordings. Kelm recommended a Torus Power AVR-45, Toroidal Isolation power transformer with automatic voltage regulation to protect equipment against voltage sags, brownouts, and surges._"
> I assume that you don't know what a Neve console is or how it worked? The Neve consoles (along with one or two others, such as SSL) were really the epitome of analogue mixing desk design but they had very demanding power supply requirements and came with a massive power supply unit which had to be located in another room. You had to turn them on and let them warm up for half an hour or more before you could use the desk and many studios never turned them off for that reason. This is all a completely different scenario from the relatively minuscule power requirements of a consumer DAC!



Marketing, the world is full of it.

The amount of Power has nothing to do with noise, the studio had noise ( quoted "_In addition," ), I raised the issue to demonstrate that a Studio had noise and how they dealt with it.

Edit  A low powered DAC will still be affected by noise._



gregorio said:


> 3. Yes, and an interesting word it is, considering how it's often misused in the audiophile world! ...



Well many words are often miss quoted nothing new there, but I was asked I replied.


----------



## gregorio

theorist said:


> Agree with your comments about the limitations of HPs and the compromises that go with them, but they can still provide a very hi-quality playback, perhaps sound stage imagining aside, for relatively small expenditure, at least compared to 5 or 6 figure amps/speaker stereo systems.



With HPs, sound stage issues is a relatively severe problem for stereo width and depth, and indeed pretty much every aspect of stereo positioning. In addition we have a problem with the amount of reverb and lastly, low frequency reproduction which even when correctly balanced has no physical impact with HPs, often leading to a requirement/desire to over-balance low freqs. None of this means that HP reproduction cannot be enjoyable, just that it cannot be high fidelity. BTW, I myself sometimes use HPs and IEMs for enjoyment. I also agree that there is significant audible variation between different HPs and therefore there most certainly can be very low and very high quality HPs. I directly implied that previously with the position I gave transducers in general in my list of most important factors. I would though dispute the 5 or 6 figure requirement for amp/speaker systems. Following my list of issue prioritisation, a 4 figure system will almost certainly out perform (provide higher fidelity) than most/all 5 or 6 figure audiophile systems. However, I agree that HPs are relatively cheap in comparison, although a direct comparison is impossible, except in terms of individual preference, because effectively we're trying to compare completely different "infidelities".



theorist said:


> [1] While you undoubtedly strive for the highest fidelity in your recordings -- thank you -- is this really the case for all studio recordings? [2] Even if mixing is no longer done on the ubiquitous Yamaha NS10 (showing my age here), a lot of mixing still appears to be being done based on near-field monitoring and with a core concern for translation so as to sound as good as possible on mass-market playback platforms, with a resultant reduction in "_high fidelity reproduction in it's true sense_".



1. Woah, hold your horses! Certainly I strive for high fidelity in my studio reproduction/monitoring, so I can hear exactly what's going on but not so much with the final product itself. This brings us back to the true definition of "hifi" and you rather falling into the impression which has been marketed to audiophiles for decades. As I mentioned previously, you really don't want me to strive for high fidelity in it's true sense, you do not want a faithful representation of what a drum kit really sounds like and you certainly don't want to hear the pathetic twang that an electric guitar really makes, you want to hear it with the tons of added distortion. In fact, this is always true, to a greater or lesser extent, of pretty much all recordings of all music genres, even classical music recordings!

2. True to an extent, although typically in commercial studios the nearfeilds are used some of the time and some of the time the main monitors. Additionally, once mixing is complete that final mix would be typically sent for mastering, in an exceptionally high fidelity monitoring environment. However, while technology has been advancing and quality should have been improving, over the last 15 years or so we have not really seen this and if anything, in general, quality has been static or even reducing. This is effectively what consumers have (unwittingly) demanded! How consumers now expect to consume and how much they are willing to pay for that consumption has resulted in the investment in making music recordings being a fraction of what it once was. The amount of time, expertise and quality of facilities used to create a recording are all greatly reduced and indeed, the vast majority of world class recording facilities have ceased to exist over the last 20 years and much of the music production process, if not all in most cases, is carried out in project studios. All this is an inevitable consequence of consumers choosing lower cost over higher quality. Maybe the situation will turn around at some point but for the foreseeable future those world class facilities are gone, along with their many decades of accumulated equipment and expertise and it seems likely that history's highest quality recordings are in the past rather than the future.



Clive101 said:


> I raised the issue to demonstrate that a Studio had noise and how they dealt with it. ... Edit A low powered DAC will still be affected by noise.



Yes it will, as I mentioned, acoustic and analogue noise are unavoidable. And therefore both a studio and a consumer DAC will always have noise, that's not in question, what's in question is how difficult it is to manage that noise! The answer to that question is entirely different for a studio running a large format analogue mixing console vs running a consumer DAC, surely you can appreciate that fact? As per the quote, does a consumer DAC get anywhere near overloading a 20 amp circuit? Hardly, it probably doesn't require much more than a hundred or so milli-amps! In this age of micro-electronics, managing power and noise issues and keeping noise below audibility is cheap and relatively trivial! Which is not the case with analogue recording/mixing studios, and is essentially why digital audio was invented in the first place!

G


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## Clive101 (Oct 9, 2017)

gregorio said:


> Yes it will, as I mentioned, acoustic and analogue noise are unavoidable. And therefore both a studio and a consumer DAC will always have noise, that's not in question, what's in question is how difficult it is to manage that noise! The answer to that question is entirely different for a studio running a large format analogue mixing console vs running a consumer DAC, surely you can appreciate that fact? As per the quote, does a consumer DAC get anywhere near overloading a 20 amp circuit? Hardly, it probably doesn't require much more than a hundred or so milli-amps! In this age of micro-electronics, managing power and noise issues and keeping noise below audibility is cheap and relatively trivial! Which is not the case with analogue recording/mixing studios, and is essentially why digital audio was invented in the first place!



I have no idea regarding an acoustic or analogue noise or studio equipment for that matter.

I would assume more equipment, more noise, more power used with regard to mains noise (and other noise for that matter) in the case of studio equipment it all adds up I guess, as I said before I am no expert and not technical but it makes sense. I am aware why digital was invented thank you. I still do not think the problem is with the how much power being used rather than the amount of equipment being used, either way I am only interested in a DAC and Server not a studio setup.

I only know that my mains electric carries noise and impacts my DAC and Server and found if I treat for noise on the mains electric the noise is reduced and hence the music sounds cleaner.

Certain USB cables reduce this noise to a greater or lesser extent ( for me ), and when I treated for noise the USB cables have less of an effect ( no comments on the placebo effect please had that one before )

I also found noise to come from the server via cat5e although Melco has an isolated port ( go figure, perhaps not ) all getting though the chain.

Low power, a number of people are spending quite a lot of money to reduce server and DAC ( combined systems ) with power supplies perhaps you could enlighten them ( not me I have found my own solution ).

Now back I thread I hope and no more about studios however interesting it may be.

I conclude in my experience mains noise is causing my USB cables to sound different, although shielding may play a role ( I have no easy way of testing for shielding ) which possibly explains why they still sound different ( less so ) when the mains is being treated.

It's my experience and posted to help people, consider my experience or not, either way, no issues with me.


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## gregorio

Clive101 said:


> [1] I would assume more equipment, more noise, more power used with regard to mains noise (and other noise for that matter) in the case of studio equipment it all adds up I guess, as I said before I am no expert and not technical but it makes sense.
> [2] ... either way I am only interested in a DAC and Server not a studio setup.
> [3] It's my experience and posted to help people, consider my experience or not, either way, no issues with me.



1. Broadly, yes this is the case. However, in reality mains power doesn't have any noise, it is after all just power not an audio signal but it does have the potential to cause noise if it isn't properly/competently handled by any particular device. Even if it is competently handled there will still always be some noise but it should be well below audibility. The important part of your statement is: "it all adds up", which is absolutely true. In an analogue studio with a large format desk we're drawing hundreds of times more mains power than your DAC and even though the resultant noise is below audibility we were typically "adding up" 24 or more channels of that noise and each of those channel had at least one if not several processors (such as EQ, etc.), each of which adds more inaudible noise. By the time we're finished we could easily have: inaudible noise  x 100 (or more) and the noise is no longer inaudible! ...

2. Absolutely agreed! The situation in an analogue mix studio, of inaudible noise being multiplied many times over, is simply not applicable to consumer playback. Indeed, it's not even applicable to studios, because the vast majority now mix digitally! So, you are completely right not to be "interested" in an analogue studio setup, which begs the question of why you decided to quote an analogue studio setup to support your argument in the first place?! Unfortunately, this happens frequently in the audiophile world, inapplicable studio practises being used to justify/market something to consumers. That's why for example we now have 24bit consumer audio and so called HRA.

3. I've got no problem with you posting your experiences to help people. In fact, you've helped me! Not that I'm currently in the market for a Dave but if your experiences are accurate, then your Dave is either faulty or incompetently designed and I now wouldn't consider getting one without considerable testing. However, your statement is not exactly true, you haven't just posted your experience, you've posted your assumptions/conclusions of those experiences, along with the implication that audiophile USB cables make a difference and are therefore valid. This is, albeit contrary to your intent, the very opposite of helping people!

G


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## Triode User

gregorio said:


> 1. Broadly, yes this is the case. However, in reality mains power doesn't have any noise, it is after all just power not an audio signal but it does have the potential to cause noise if it isn't properly/competently handled by any particular device. Even if it is competently handled there will still always be some noise but it should be well below audibility. The important part of your statement is: "it all adds up", which is absolutely true. In an analogue studio with a large format desk we're drawing hundreds of times more mains power than your DAC and even though the resultant noise is below audibility we were typically "adding up" 24 or more channels of that noise and each of those channel had at least one if not several processors (such as EQ, etc.), each of which adds more inaudible noise. By the time we're finished we could easily have: inaudible noise  x 100 (or more) and the noise is no longer inaudible! ...
> 
> 2. Absolutely agreed! The situation in an analogue mix studio, of inaudible noise being multiplied many times over, is simply not applicable to consumer playback. Indeed, it's not even applicable to studios, because the vast majority now mix digitally! So, you are completely right not to be "interested" in an analogue studio setup, which begs the question of why you decided to quote an analogue studio setup to support your argument in the first place?! Unfortunately, this happens frequently in the audiophile world, inapplicable studio practises being used to justify/market something to consumers. That's why for example we now have 24bit consumer audio and so called HRA.
> 
> ...



G, I hope you will not mind paraphrasing.

YOU SAY - You are professional sound engineers and you know what you are doing. If there was any RF or EMF noise issue you would have noticed it in the studio playback.
I SAY - Really? Are you sure? It can be subtle and the music still sounds pretty good. Fantastic even. My Dave sounds fantastic. I just happen to think it sounds even better if I put RF filters on the input cables. When you are listening to playback I am assuming you have a job in hand concerning the mixing etc and if truth be told, the absolute quality of the sound is not going to affect your ability to do that job. I am sure the sound in your studio sounds magnificent but are you sure it is not a case of near enough is good enough?

YOU SAY - designing a DAC to be RF noise tolerant is ridiculously easy and cheap to do and any competently designed DAC should cope with this. You therefore say the professional DACs are not affected by any RF noise coming into them.
I SAY - How do you know this is the case with the DACs you use? In any case is it not better practice to filter out the RF noise before it gets into a DAC or other equipment?

YOU SAY - If the Dave is affected by RF on it's inputs then it is either broken or badly designed.
I SAY - It would be interesting to take one of the professional DACs you mention and see if filtering the inputs for RF noise makes any difference.


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## Clive101 (Oct 10, 2017)

gregorio said:


> 1. Broadly, yes this is the case. However, in reality mains power doesn't have any noise, it is after all just power not an audio signal but it does have the potential to cause noise if it isn't properly/competently handled by any particular device. Even if it is competently handled there will still always be some noise but it should be well below audibility. The important part of your statement is: "it all adds up", which is absolutely true. In an analogue studio with a large format desk we're drawing hundreds of times more mains power than your DAC and even though the resultant noise is below audibility we were typically "adding up" 24 or more channels of that noise and each of those channel had at least one if not several processors (such as EQ, etc.), each of which adds more inaudible noise. By the time we're finished we could easily have: inaudible noise  x 100 (or more) and the noise is no longer inaudible! ...
> 
> 2. Absolutely agreed! The situation in an analogue mix studio, of inaudible noise being multiplied many times over, is simply not applicable to consumer playback. Indeed, it's not even applicable to studios, because the vast majority now mix digitally! So, you are completely right not to be "interested" in an analogue studio setup, which begs the question of why you decided to quote an analogue studio setup to support your argument in the first place?! Unfortunately, this happens frequently in the audiophile world, inapplicable studio practises being used to justify/market something to consumers. That's why for example we now have 24bit consumer audio and so called HRA.
> 
> ...



Analogue quoted to represent my situation. The Analogue part of my chain is amplifying the mains noise !
Noise is often used but it's a term that is misleading as you cannot technically hear the noise but you notice when it has been reduced.
I am surprised you had not realised this coming from a Studio background.

Quote  "It's my experience and posted to help people, consider my experience or not, either way, no issues with me." does not imply what you suggest.


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## gregorio (Oct 11, 2017)

Triode User said:


> YOU SAY - You are professional sound engineers and you know what you are doing. If there was any RF or EMF noise issue you would have noticed it in the studio playback.
> [1] I SAY - Really? Are you sure? It can be subtle and the music still sounds pretty good. Fantastic even. My Dave sounds fantastic. I just happen to think it sounds even better if I put RF filters on the input cables. [1a] When you are listening to playback I am assuming you have a job in hand concerning the mixing etc and if truth be told, the absolute quality of the sound is not going to affect your ability to do that job. [1b] I am sure the sound in your studio sounds magnificent but are you sure it is not a case of near enough is good enough?
> 
> YOU SAY - designing a DAC to be RF noise tolerant is ridiculously easy and cheap to do and any competently designed DAC should cope with this. You therefore say the professional DACs are not affected by any RF noise coming into them.
> ...



1. I frequently have to take a signal or part of a signal from my ADC/DAC and amplify it by 50dB or even more, then it goes through the usual round of further amplification for the speakers and out into an exceptionally quiet and accurate listening environment. So yes, I am pretty sure!
1a. It depends on the exact circumstances but "truth be told" a considerable amount of the time, the absolute quality of sound is going to seriously affect my job and is of paramount importance!
1b. My studio is not designed to sound magnificent, it's designed to accurately reproduce an audio signal. Whether or not someone thinks that sounds magnificent is down to personal preference and in my experience some/many audiophiles do not. It is though, always a case of near enough is good enough, as even spending tens of millions does not result in a perfect monitoring environment. Incidentally, my job sometimes requires me to manipulate/generate/manufacture the background noise/ambience of numerous different real life environments. It's for this reason that my monitoring environment needs to be exceptionally quiet, otherwise I wouldn't be able to tell what I'm actually putting into the audio files I'm creating and what is just the background noise of my monitoring environment.

2. I refer you to my response above, plus, I often have to take recordings from other pro ADC/DACs, recorded in a variety of non-optimal locations and do the same thing, massively amplify the signal or part of it. This amplification + my monitoring environment should make any interference (RF, EM or other noise) particularly noticeable or at the least, way more so than in any consumer scenario.
2a. A DAC has just one job, to convert digital audio data into an analogue signal as accurately as possible, and that obviously means without ANY audible interference (noise, distortion, interference). That could be achieved by the best pro audio ADC/DACs at least 25 years ago, today it can be achieved in any pro audio ADC/DAC, even the very cheap ones. Therefore, in a modern ADC/DAC, filtering out RF noise before it gets to the DAC should make absolutely no difference and if it did, it could only be because the ADC/DAC has defective isolation from RF noise.

3. It's one thing to have signal to noise ratio specs from a manufacturer in whatever controlled environment they did their testing and another to use one or an entire bank of ADC/DACs day in and day out in the interference rich and demanding conditions of pro studios. Any deficiency or susceptibility to interference would quickly be identified and that piece of equipment replaced or not purchased in the first place. This is true of any piece of studio equipment and has been for decades! So no, it wouldn't be an interesting experiment, it would be pointless. Even if there were any difference, it would have to be many, many times below audibility otherwise it would have already been identified.



Clive101 said:


> [1] Analogue quoted to represent my situation. The Analogue part of my chain is amplifying the mains noise !
> [2] Noise is often used but it's a term that is misleading as you cannot technically hear the noise but you notice when it has been reduced.
> I am surprised you had not realised this coming from a Studio background.
> [3] Quote  "It's my experience and posted to help people, consider my experience or not, either way, no issues with me." does not imply what you suggest.



1. Quoting a whole studio worth of equipment, with hundreds of simultaneous audio paths which are summed together, is hardly "representative" of a single piece of audio equipment with just one (stereo) path. What you've quoted does not support your argument, it contradicts it! If the individual audio paths in any studio were to amplify mains noise to anywhere near audibility, then the cumulative effect would be utterly horrendous amounts of "mains noise" and a completely unusable, seriously defective product!

2. I've no idea where you got that from, it's completely backwards! It's because I work in a studio that I DO know that noise can be heard. In fact, as I stated above, I often have to manipulate/process or create environmental noise floors, which would obviously be impossible if I couldn't actually hear what I was doing!

3. Again, you did not just post your experience/observations, you posted your assumptions on the cause of them!!

G


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## Clive101

gregorio said:


> 1. I frequently have to take a signal or part of a signal from my ADC/DAC and amplify it by 50dB or even more, then it goes through the usual round of further amplification for the speakers and out into an exceptionally quiet and accurate listening environment. So yes, I am pretty sure!
> 1a. It depends on the exact circumstances but "truth be told" a considerable amount of the time, the absolute quality of sound is going to seriously affect my job and is of paramount importance!
> 1b. My studio is not designed to sound magnificent, it's designed to accurately reproduce an audio signal. Whether or not someone thinks that sounds magnificent is down to personal preference and in my experience some/many audiophiles do not. It is though, always a case of near enough is good enough, as even spending tens of millions does not result in a perfect monitoring environment. Incidentally, my job sometimes requires me to manipulate/generate/manufacture the background noise/ambience of numerous different real life environments. It's for this reason that my monitoring environment needs to be exceptionally quiet, otherwise I wouldn't be able to tell what I'm actually putting into the audio files I'm creating and what is just the background noise of my monitoring environment.
> 
> ...



Again you quote studio equipment again I have no interest so will not respond.
I quoted Torus as it was used to treat for mains noise as I had  noise.
I have nothing more to add and no longer wish to respond to your posts.


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## gregorio

Clive101 said:


> Again you quote studio equipment again I have no interest so will not respond. ... I have nothing more to add and no longer wish to respond to your posts.



Sorry, but you sound like you've lost your marbles! You state "_I quoted Torus as it was used to treat for mains noise as I had  noise._" - Yes indeed, you quoted the use of Torus with a whole bunch of STUDIO EQUIPMENT! You are the one who quoted the studio equipment and used it to "represent" your situation/DAC and now you're saying you have no interest and will not respond to what you yourself stated/quoted?!

In any event, it's a wise decision to not respond any further and dig an even deeper hole yourself.

G


----------



## castleofargh

arrrgh. Y U do dis, admin? now that it moved to sound science I have to care again.  
 most arguments are based on unreliable listening tests and at best anecdotal evidence used to jump to conclusions. it makes the heart of the debate pretty much irrelevant for this sub section's tentative standards of objective based arguments. I can't just tolerate fallacies and "I know what I heard" as evidence, just to keep the general tone of the topic. but if everybody becomes accountable for what they claim overnight, some will be very frustrated because it's not what they signed for when joining the topic(where was it initially, cable section?). I've been given a poop sandwich. ^_^


----------



## Ike1985 (Oct 11, 2017)

Can someone give me an answer, yes or no.  I have Hugo2 and I'm running Zeus XR and A18 with it.  I currently just use a cheap cable to micro-b to usb-c cable to connect it to my phone.  Would I benefit from dropping coin on some audiophile style cable if I'm just using it in this manner?


----------



## bigshot

No need for a fancy cable. If a USB cable is bad, you know it. It either works or it doesn't. If you aren't getting skipping and dropouts, your current cable is as good as any other cable, regardless of price.


----------



## Leo-

@castleofargh, not sure if I get the whole of your cryptic post but...



bigshot said:


> No need for a fancy cable. If a USB cable is bad, you know it. It either works or it doesn't. If you aren't getting skipping and dropouts, your current cable is as good as any other cable, regardless of price.



here we go again


----------



## castleofargh

Ike1985 said:


> Can someone give me an answer, yes or no.  I have Hugo2 and I'm running Zeus XR and A18 with it.  I currently just use a cheap cable to micro-b to usb-c cable to connect it to my phone.  Would I benefit from dropping coin on some audiophile style cable if I'm just using it in this manner?


it's easy to reply something, but you must realize that nobody has what it takes to make a confident reply. we don't know your circumstances, we don't know the state of the cable you're using, we don't even know if you have any significant issue to begin with. 
so just dropping a "yes" or a "no" answer would be irresponsible. I get the insecurity and desire to be reassured by definitive answers, but the real world isn't that simple. also "benefit" can be interpreted anyway we like from hardly measurable improvement on a variable, to clearly audible improvement. can a better cable marginally improve something, yes, of course. does it matter? that's subjective. will it be audible? well we'd first need to know what's going on right now and we don't.


----------



## bigshot

I'll take responsibility. I've had bad USB cables in the past. I knew I had them. Errors that cause audible artifacts are generally huge and obvious. If it sounds OK, it probably is OK. No need to worry about it.


----------



## Strangelove424

I bet a person could make a lot of money selling giant Faraday cages to audiophiles. And the same business could also cater to the celebrity "safe room" market.


----------



## theorist

Strangelove424 said:


> I bet a person could make a lot of money selling giant Faraday cages to audiophiles. And the same business could also cater to the celebrity "safe room" market.



Makes sense, any ideas how best these Faraday cages be properly grounded and isolated from the RF/EMI noise of mains power?


----------



## castleofargh

theorist said:


> Makes sense, any ideas how best these Faraday cages be properly grounded and isolated from the RF/EMI noise of mains power?


get some of Elon Musk's big batteries for solar stuff, and put it inside the Faraday cage with the rest of the system and yourself. with some mean to disconnect the battery from it's power source when listening to music. I would suggest doing that underground in a bunker for better sound isolation. it can also serve for other paranoia and survival concepts.
but I'm afraid even the batteries will have measurable noise. it's really hard to make perfect stuff even for irrelevant reasons.


----------



## theorist

castleofargh said:


> but I'm afraid even the batteries will have measurable noise. it's really hard to make perfect stuff even for irrelevant reasons.



What about putting some solar panels on top of the bunker then? Do solar flares cause noise?


----------



## castleofargh

the charging process probably does and the panel could act as an antenna I guess. I have a fair amount of imagination but not a lot of actual knowledge on solar panels. ^_^


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## JaeYoon (Oct 11, 2017)

I think it's very important to have Digital Data classes possibly implemented in U.S Educational system in future.

It will at least help reduce level of scamming on audiophile USB cables. We don't even know if audiophile usb cables conforms to the USB Standards. What if they intentionally drifted away from the standard to add noise or some junk to make the consumer think because it sounds different from a bitperfect cable you can get from Amazon Basics for 99c, "it's better cuz it's audiophile"

The minute I see "audiophile" labelled on any product, I avoid.

Edit: lol. I meant the second I see it. Don't need to think twice before I think something is wrong with the product.


----------



## pinnahertz

Triode User said:


> G, I hope you will not mind paraphrasing.
> 
> YOU SAY - You are professional sound engineers and you know what you are doing. If there was any RF or EMF noise issue you would have noticed it in the studio playback.
> I SAY - Really? Are you sure?


As another professional, one who's worked around lots of RF of all kinds...yes, he's sure, and so am I.  RF and EM noise is easy...very, very easy...to detect through test and measurement.  It's not subtle.


Triode User said:


> It can be subtle and the music still sounds pretty good.


No, it's not subtle at all, very easy to detect with the correct test and measurement.


Triode User said:


> My Dave sounds fantastic._* I just happen to think it sounds even better if I put RF filters on the input cables.*_


I've bolded and italicized your answer.


Triode User said:


> When you are listening to playback I am assuming you have a job in hand concerning the mixing etc and if truth be told, the absolute quality of the sound is not going to affect your ability to do that job. I am sure the sound in your studio sounds magnificent but are you sure it is not a case of near enough is good enough?


Seriously?  You must be under the delusion than we're all deaf to the problems noise causes.  Any professional who has been involved in studio design has chased noise down to death.  Again, I can assure you, we know it, we hear it if it's there, and we eradicate it at the source, not put some pseudoscientific band-aid not it.  There's an entry point or a cause for any and all noise.  You find it, you fix it, eliminate badly designed gear, or it's thermal and part of working in the real world of electronics.  

I'd have to say with complete confidence that audio professionals are hyper-sensitive to noise of all kinds, as it's something highly undesirable in our lives that most of us have worked hard to get rid of.


Triode User said:


> YOU SAY - designing a DAC to be RF noise tolerant is ridiculously easy and cheap to do and any competently designed DAC should cope with this. You therefore say the professional DACs are not affected by any RF noise coming into them.
> I SAY - How do you know this is the case with the DACs you use? In any case is it not better practice to filter out the RF noise before it gets into a DAC or other equipment?


Measurement.  It's not hard to do.  Instrumentation sensitive enough to detect any and all forms of noise has been around in many forms for many, many decades.  RF noise is no exception.  Every engineer working with signals of the kind and frequency found in computers knows RFI quite well.  We look for it, and deal with it. 


Triode User said:


> YOU SAY - If the Dave is affected by RF on it's inputs then it is either broken or badly designed.
> I SAY - It would be interesting to take one of the professional DACs you mention and see if filtering the inputs for RF noise makes any difference.


And I SAY it would be easy to test for, and if I found RF in inputs bothering Dave I assume bad design.  It's hard for something to "break" and cause that problem.  Again, test and measurement would do it quickly and easily.  As far as a Pro DAC, RF immunity is central to pro audio design.  A good many studios are located in high RF environments.  Radio stations are clearly obvious, but many recording studios are in urban areas where TV and radio transmitters abound.  That stuff can get in anywhere, so well designed gear must take that situation into account.  In the cost of design, RF proofing is relatively painless especially when compared to the customer support issues the lack of it causes.


----------



## Arpiben

Strangelove424 said:


> I bet a person could make a lot of money selling giant Faraday cages to audiophiles. And the same business could also cater to the celebrity "safe room" market.



Add conic foams inside for it to become an anechoic chamber...Lot of options indeed.
The positive for those outside: no noise, no EMI/RFI from inside audiophile and its equipment.
The negative for audiophile insider is that he may still need dedicated USB/BNC cables or ferrites in order to reduce EMI/RFI generated by its own equipment.


----------



## gregorio

It's a real shame this thread has been moved from the cables forum where it might actually have provided some helpful, informed knowledge to the users of that forum. Moving it here is pointless because pretty much all the users here already know the answers to the thread's question. I assume it was moved here because "informed knowledge" is contrary to the benefits which head-fi gains from having a cables forum, shame!

G


----------



## Triode User

Some of the discussion in this thread has centred around whether particular 'high end' DACs are properly designed and implemented if they suffer when RF enters them via their inputs. In particular the DAC that I and others use, the Chord Dave, has jokingly been referred to as 'broken' because we have found that RF filtering ferrites on the input USB cable do improve the sound. 

A reminder of a summery post of the Dave's designers comments has just resurfaced on the Dave thread and it might be enlightening in the context of this USB cable thread. The discussion regarding the Dave's USB inputs and RF is slightly buried but persevere it is in there.

https://www.head-fi.org/threads/chord-electronics-dave.766517/page-94#post-12262339


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## Clive101 (Oct 12, 2017)

Triode User said:


> Some of the discussion in this thread has centred around whether particular 'high end' DACs are properly designed and implemented if they suffer when RF enters them via their inputs. In particular the DAC that I and others use, the Chord Dave, has jokingly been referred to as 'broken' because we have found that RF filtering ferrites on the input USB cable do improve the sound.
> 
> A reminder of a summery post of the Dave's designers comments has just resurfaced on the Dave thread and it might be enlightening in the context of this USB cable thread. The discussion regarding the Dave's USB inputs and RF is slightly buried but persevere it is in there.
> 
> https://www.head-fi.org/threads/chord-electronics-dave.766517/page-94#post-12262339





romaz said:


> If the Zenith was comparable to the Antipodes DX in sound quality, that's saying a lot and it gives me some point of reference I can relate to as I hold the DX in very high regard.  I have heard the Melco also and while SQ was very good (also better than the microRendu), I agree, lack of Roon was a deal breaker, especially since Melco's interface options are so archaic in comparison.
> 
> You are correct, technology in the area of music servers is advancing quickly and rapidly becoming less expensive which is good for all consumers.  There is no longer any justification for buying something like a $17k Aurender W20 as I long ago surpassed the SQ I was getting from a W20 at a fraction of the cost.  Having opened up and taken apart several of these well-regarded servers and as I have assessed the individual impact of various components, I have drawn the conclusion that it boils down to 3 things:  low noise, low latency and low impedance -- but this is easier said than done.
> 
> ...





Thank you Triode I had also added a quote from Romaz in particular,

  "I believe the benefits heard by applying ferrite filters to cables proves very well DAVE's galvanic isolation is not 100 percent, and it's not just noise in the ground plane that's the issue but more importantly, noise that gets permanently imbedded into the signal that can't be removed because at some point, I believe, this noise becomes part of the signal."

It may explain ...?


----------



## gregorio

Triode User said:


> In particular the DAC that I and others use, the Chord Dave, has jokingly been referred to as 'broken' because we have found that RF filtering ferrites on the input USB cable do improve the sound.



I was not joking, I was being absolutely serious! In fact, if your observation is to be believed, that is the only logical conclusion!! ...


romaz said:


> So the solution to the above problems is galvanic isolation. This means that RF noise from the source can't get into Dave, and small correlated currents can't get in too.



According to you the above is Dave's designer and he's saying that RF noise "can't get into Dave". If you have found that filtering RF noise changes the sound from Dave, there are only two possibilities: 
1. There is no change in the sound, you are imagining it. or
2. RF noise _IS_ getting into Dave, Dave's galvanic isolation is not functioning as stated/designed and is therefore "broken"!!

G


----------



## Triode User

Clive101 said:


> Thank you Triode I had also added a quote from Romaz in particular,
> 
> "I believe the benefits heard by applying ferrite filters to cables proves very well DAVE's galvanic isolation is not 100 percent, and it's not just noise in the ground plane that's the issue but more importantly, noise that gets permanently imbedded into the signal that can't be removed because at some point, I believe, this noise becomes part of the signal."
> 
> It may explain ...?



But not to me as I haven't a clue what Romaz means by the possibility of permanently imbedded noise but then it would not be the first time I was clueless.


----------



## Clive101

Triode User said:


> But not to me as I haven't a clue what Romaz means by the possibility of permanently imbedded noise but then it would not be the first time I was clueless.



I am some what puzzled as well  ( not lost my marbles ) I assume "all" realise I am not technical in the field of Audio.

I assumed ( guessed ) I had mains noise and tried a Torus Power supply, SQ improved and the gap in SQ between USB cables got closer. ( please no placebo  comments from anyone ).

Personally IMO ( and that's all it is ) it could be Audiophile people some how pick up on the noise issue however small and it's very small which got me wondering, do Studio people listen for it in a domestic situation, I guess they do but are they that bothered in tiny detail that perhaps we are, which might explain..?

"permanently imbedded noise" some how the conversion of zeros and ones to analogue noise gets added...?

I guess we have gone full circle again back to a faulty DAC perhaps we should get one of $80.00 pro dac and sell DAVE..?


----------



## gregorio (Oct 12, 2017)

Clive101 said:


> Personally IMO ( and that's all it is ) it could be Audiophile people some how pick up on the noise issue however small and it's very small which got me wondering, do Studio people listen for it in a domestic situation, I guess they do but are they that bothered in tiny detail that perhaps we are, which might explain..?



That and similar statements is a common assumption by some audiophiles, presumably to avoid the two options I posted in my previous post! We do indeed listen for noise in a domestic situation but more importantly, we listen for it in a studio which has been specifically designed to be far quieter than a domestic situation and which therefore reveals noise which would be inaudible beneath the much higher noise floor of any domestic situation! And, not only do we listen for noise, we often actively create or process/manipulate it! I've mentioned all this before, in prior posts. I've also mentioned that: "_we are hearing details significantly more accurately than any audiophile system is capable of, details which few, if any, audiophiles are even consciously aware exist and we're not just hearing those details but actively working/processing/manipulating them!_". I do not accept your assumption, I guarantee that I can aurally dissect any recording and identify numerous details you don't even know exist. This isn't because my hearing is intrinsically any better than yours but because I have decades of training/experience in focusing my attention on different elements of what I'm hearing and because I know the details of what has been done to create a recording.



Triode User said:


> I haven't a clue what Romaz means ...



I started reading the post you linked to and while there are some accurate facts in there, they're often misrepresented and others are just completely wrong. It was so full of nonsense that I gave up and just scrolled down to the part about RF. There were a couple of parts which I loved though, for example "_As you can see, the jitter subject can get complicated and its often abused by marketing..." - _IMO, this one of the greatest achievements in human history, in the field of irony!

This is another beauty: "_The FPGA uses a digital phase lock loop (DPLL) and a tiny buffer. This re-clocks the data and eliminates the incoming jitter from the source. This system took 6 years to perfect, and means that the sound quality defects from source jitter is eliminated." - _Alternatively, he could have gone to Alibaba and bought a hundred re-clocking circuits (which do exactly what he describes), for about a buck each and not wasted 6 years solving a problem which was solved many years ago! And, what did he do during those 6 years before he managed to (re-)invent the wheel, sell DACs with faulty re-clocking circuitry?

G


----------



## Arpiben (Oct 12, 2017)

First of all since we can't measure your DAC's noise susceptibility I will not coment on its design.
What I have been finding interesting & strange when reading its thread is that owners seem to use ferrite chokes with USB inputs and also with BNC digital Ins/Outs when DAC is connected to BlueMk2. Apparently the designer suggested the use of chokes suited for 300MHz (BNC I guess). Now people keep trying their luck with more or less ferrites in serial without any indication at all of their value!
As mentioned by @pinnahertz it would be very easy to measure and take only a couple of minutes....
Without it, we keep dealing with assumptions.
Your DAC is oversampling & noise shaping at frequencies around 100MHz.
Is it a reason for it to be more sensitive to RF, no idea?
Designer is suggesting ferrites for a LP at 300MHz with BNC digital. Is it because Dave or BlueMk2 generates too much EMI,no idea either?


----------



## Triode User

gregorio said:


> That and similar statements is a common assumption by some audiophiles, presumably to avoid the two options I posted in my previous post! We do indeed listen for noise in a domestic situation but more importantly, we listen for it in a studio which has been specifically designed to be far quieter than a domestic situation and which therefore reveals noise which would be inaudible beneath the much higher noise floor of any domestic situation! And, not only do we listen for noise, we often actively create or process/manipulate it! I've mentioned all this before, in prior posts. I've also mentioned that: "_we are hearing details significantly more accurately than any audiophile system is capable of, details which few, if any, audiophiles are even consciously aware exist and we're not just hearing those details but actively working/processing/manipulating them!_". I do not accept your assumption, I guarantee that I can aurally dissect any recording and identify numerous details you don't even know exist. This isn't because my hearing is intrinsically any better than yours but because I have decades of training/experience in focusing my attention on different elements of what I'm hearing and because I know the details of what has been done to create a recording.
> 
> I started reading the post you linked to and while there are some accurate facts in there, they're often misrepresented and others are just completely wrong. It was so full of nonsense that I gave up and just scrolled down to the part about RF. There were a couple of parts which I loved though, for example "_As you can see, the jitter subject can get complicated and its often abused by marketing..." - _IMO, this one of the greatest achievements in human history, in the field of irony!
> 
> ...



You've convinced me that Rob Watts doesn't know what he is talking about and his DACs are broken. Well at least life will be less expensive now.

OK, I'm out of this now.


----------



## Clive101

gregorio said:


> That and similar statements is a common assumption by some audiophiles, presumably to avoid the two options I posted in my previous post! We do indeed listen for noise in a domestic situation but more importantly, we listen for it in a studio which has been specifically designed to be far quieter than a domestic situation and which therefore reveals noise which would be inaudible beneath the much higher noise floor of any domestic situation! And, not only do we listen for noise, we often actively create or process/manipulate it! I've mentioned all this before, in prior posts. I've also mentioned that: "_we are hearing details significantly more accurately than any audiophile system is capable of, details which few, if any, audiophiles are even consciously aware exist and we're not just hearing those details but actively working/processing/manipulating them!_". I do not accept your assumption, I guarantee that I can aurally dissect any recording and identify numerous details you don't even know exist. This isn't because my hearing is intrinsically any better than yours but because I have decades of training/experience in focusing my attention on different elements of what I'm hearing and because I know the details of what has been done to create a recording.
> 
> 
> 
> ...



Thanks for the reply but you went back into studio mode.
Perhaps I should had been more detailed with my question, in a domestic situation when you listen with your trained ear and expertise you would notice noise to a greater extent than for example me. Buy what you say it's a yes !


----------



## pinnahertz

gregorio said:


> I was not joking, I was being absolutely serious! In fact, if your observation is to be believed, that is the only logical conclusion!! ...
> 
> 
> According to you the above is Dave's designer and he's saying that RF noise "can't get into Dave". If you have found that filtering RF noise changes the sound from Dave, there are only two possibilities:
> ...


I think part of the confusion here is that galvanic isolation is all that is required for perfect RF immunity.  It's one method, a good one, you just can't use it for everything, and there are many possibly entries for RF.  A circuit could employ galvanic isolation and still be susceptible to RFI because it enters the circuit via another path.  For example, have they galvanically isolated the output?  Is the case fully shielded?  You can't galvanically isolate the power input, so there's another.  The term is kicked around like it's the be-all/end-all, it's good at what it does, just not the whole story.   And it is possible to make a circuit RF immune without GI.


----------



## bigshot (Oct 12, 2017)

gregorio said:


> It's a real shame this thread has been moved from the cables forum where it might actually have provided some helpful, informed knowledge to the users of that forum. Moving it here is pointless because pretty much all the users here already know the answers to the thread's question. I assume it was moved here because "informed knowledge" is contrary to the benefits which head-fi gains from having a cables forum,



I think it's more akin to throwing the Christians to the lions.



Clive101 said:


> Audiophile people some how pick up on the noise issue however small and it's very small which got me wondering, do Studio people listen for it in a domestic situation?



I've worked a bit in production sound and when I get home, I listen to music.


----------



## pinnahertz

Clive101 said:


> I am some what puzzled as well  ( not lost my marbles ) I assume "all" realise I am not technical in the field of Audio.
> 
> I assumed ( guessed ) I had mains noise and tried a Torus Power supply, SQ improved and the gap in SQ between USB cables got closer. ( please no placebo  comments from anyone ).


What? No placebo comments?  But....but....I....trying....to....hold....back....ARRGG!


Clive101 said:


> Personally IMO ( and that's all it is ) it could be Audiophile people some how pick up on the noise issue however small and it's very small which got me wondering, do Studio people listen for it in a domestic situation, I guess they do but are they that bothered in tiny detail that perhaps we are, which might explain..?


It's hard for me not to be analytical in casual listening, but if the music is good I tend to relax and push that stuff to the background.  If there's something wrong that should not be there, I'll hear it.


Clive101 said:


> I guess we have gone full circle again back to a faulty DAC perhaps we should get one of $80.00 pro dac and sell DAVE..?


What's an "$80 Pro DAC" look like?


----------



## Leo-

@pinnahertz very good words, RF is definitely the issue that gets transmitted through digital inputs. It's bad with USB, typically not that much with Ethernet (although badly constructed cables with shorted shields can ruin them) and optical inputs are typically immune to it (but one needs to watch out for bad transmitters problems though). I don't know much about Coax though, seems to be quite a mixed bag.

Regarding noise interference, there are basically two types of noise. I've already hinted at this before in the thread, which got lost in the noise (sic) of some other forum members who don't grasp the basic concepts of signal transmission. There is signal-independent noise - like mains hum that is basically AC signal that "leaks" due to magnetic effects on transformers and is of constant level and is simply amplified by the system. If you play jazz, classical or rock it will always be there with same intensity. This type of noise is not a big real issue since our brains are quite efficient in filtering out this sound, and the signal is not affected at all.

The bad noise is signal-correlated noise, which means that the analog signal gets affected by the noise injected in the system. This is typical of RF noise, which interfere with components like capacitors which get discharged at very high frequencies and this does indeed affect the signal. The RF noise itself is inaudible, however _in the presence of RF noise_ the analog components will produce an altered signal which is then perceived as altered sound.

When you put a choke on a USB cable feeding a Dave, you reduce some RF frequencies that reach either Dave's PS or other analog parts. Dave should be insensitive to timing changes in the digital signal, however in theory the chokes affect the raise times of the digital signal (remember that the choke affects any current changes in the cable) which can adversely affect the timings of the signal, so folks avoid chokes if you can.


----------



## castleofargh

the Odac measures slightly better with ferrite(and it's not limited to mine). the cable provided had some, so is it considered part of the design, or does it need to be inside the box to count? ^_^
 the fact that it's a cheap old usb powered device makes it more forgivable to me than when talking about a 10k$ DAC. I guess I'm a subjectivist in that way.

*warning, crazy person ranting!*

 I trust evidence over people and find discussing noise without any measurement completely ludicrous. just like assuming a causation from a sighted test about fooling around with cables. could be right, could be wrong, it doesn't matter because we have no control to help checking if anything is legit. pure waste of time. even if we were to admit that some impression is real(not yet established), and somehow accept that the correlation is in this specific case, causation(not established and often false). how do we know that it's relevant for another DAC or even the same DAC in a different house with a different computer? how do we know when what the dude heard as better, was really better or personal taste and assumptions?
I'm amazed that anybody can be satisfied after reaching conclusions that way. we're discussing stuff like digital cables and how they somehow should filter a noise which apparently we don't want measured in any way for some reason. because you know, fidelity, that stuff defined entirely by measurements compared to a reference, it's not as good as subjective impression from a super flawed listening "test".
I can't help but being sarcastic, the all thing make no sense.

a few years back all the rage was jitter, everybody was hearing it and how much better the sound was when the anti jitter whatever was stamped on the box. turns out humans are probably not able to notice jitter at the levels often found in consumer gears(while playing music content). in the end, most people don't have a clue what jitter sounds like or how different sorts of jitter might sound different. it's all made up, the marketing guy told us to fear jitter and everybody started "hearing" it.
next comes ringing and dac filters, the time smearing jokes. so now I buy the DAC with the anti time smearing written on the box and anything I notice as a difference (or anything I make up in my head) is thanks to the reduced ringing. and no matter how controlled experiments suggest we don't hear the ringing at 20-something khz from the band limiting. "hermaggerd! ringinrgg! it sounds so bad on those DACs that don't market anti time smearing tech. "
when did technical issues become fashionable? "oh dear you still focus on jitter? poor thing, it's been 3 years since anybody famous cared about jitter. were you living in a cave? now it's all about noise from the computer. it's completely different, but also the same."

I have no doubt that some gears are better than others and that some DACs are better at blocking particularly bad noises from unreasonably bad computers, and power grids, and leaky microwave we keep turned on for some reason. but paranoia and taking all the drugs in advance in case we might have one sickness, well it's not clever. proper diagnostic is what leads to a good treatment, if needed. and proper diagnostic, that's not a sighted test. never was, never will be.


----------



## Leo-

castleofargh said:


> I trust evidence over people and find discussing noise without any measurement completely ludicrous. just like assuming a causation from a sighted test about fooling around with cables. could be right, could be wrong, it doesn't matter because we have no control to help checking if anything is legit. pure waste of time. even if we were to admit that some impression is real(not yet established), and somehow accept that the correlation is in this specific case, causation(not established and often false). how do we know that it's relevant for another DAC or even the same DAC in a different house with a different computer? how do we know when what the dude heard as better, was really better or personal taste and assumptions?
> I'm amazed that anybody can be satisfied after reaching conclusions that way. we're discussing stuff like digital cables and how they somehow should filter a noise which apparently we don't want measured in any way for some reason. because you know, fidelity, that stuff defined entirely by measurements compared to a reference, it's not as good as subjective impression from a super flawed listening "test".
> I can't help but being sarcastic, the all thing make no sense..



This is true, and one hint that typically can be seen is when "detail" and "brightness" are noticed not only when assessing digital cables. Some sound artifacts can be created e.g. due to excessive capacitance in analog path that may induce people to perceive sound as brighter or more detailed when in reality the signal is actually being distorted on the way. We have that sometimes what may sound more pleasant to the ears may actually be due to a degradation in the sound quality.


----------



## theorist

pinnahertz said:


> What's an "$80 Pro DAC" look like?



If an $80 Pro DAC, regardless of how it looked, sounded as good as a mega-dollar DAC, like a Dave, don't you think that market rationality would prevail, at least for most of us, and we would all be using these $80 Pro DACs! But of course we don't because the (likely) accurate analytical sound the $80 Pro DAC produces, while fine for commercial studio mixing, etc, does not sound anywhere near as 'good' to the consumer's ears for enjoyable musicality as does the Dave. This similar logic applies to generic and dedicated audio USB cables as well. They do sound different and this is readily apparent in blind listening testing as my post #205 in this thread confirmed.


----------



## Clive101

pinnahertz said:


> What? No placebo comments?  But....but....I....trying....to....hold....back....ARRGG!
> It's hard for me not to be analytical in casual listening, but if the music is good I tend to relax and push that stuff to the background.  If there's something wrong that should not be there, I'll hear it.
> 
> What's an "$80 Pro DAC" look like?



Ok you made me smile about the placebo.
Below is the $80.00 in answer to Triode but looking at the product it may not be a DAC...?



gregorio said:


> A typical DAC used in commercial studios would be the AVID HD I/O or the Apogee Symphony. However, these are typical big ADC/DAC units with 16/32 ins and outs, all the bells and whistles, price tags well into the 4 figures and not really applicable to audiophiles. However, there is a large range of pro audio ADC/DACs which are designed for musicians and smaller project studios, fewer ins and outs and great value for money. A typical one would be the (apparently) best selling USB audio interface in the world, the Focurite Scarlett but surprisingly competently designed for the price is the Behringer UMC204HD, actually it's performance is almost shocking considering the quality of conversion and the amount of functionality you get for just $80.
> 
> G


----------



## ev13wt

21 pages, eh?

Wow.


----------



## pinnahertz

Leo- said:


> @pinnahertz very good words, RF is definitely the issue that gets transmitted through digital inputs. It's bad with USB, typically not that much with Ethernet (although badly constructed cables with shorted shields can ruin them) and optical inputs are typically immune to it (but one needs to watch out for bad transmitters problems though). I don't know much about Coax though, seems to be quite a mixed bag.
> 
> Regarding noise interference, there are basically two types of noise. I've already hinted at this before in the thread, which got lost in the noise (sic) of some other forum members who don't grasp the basic concepts of signal transmission. There is signal-independent noise - like mains hum that is basically AC signal that "leaks" due to magnetic effects on transformers and is of constant level and is simply amplified by the system. If you play jazz, classical or rock it will always be there with same intensity. This type of noise is not a big real issue since our brains are quite efficient in filtering out this sound, and the signal is not affected at all.
> 
> ...


I'd add a few to your two types.  Demodulated RFI can be audible on its own.  I live 5 miles from a 50kW directional AM station in the main lobe, for example.  That RF gets demodulated everywhere that's not had some form of RFI protection, and you get to hear the station in full fidelity.   FM signals (broadcast or 2-way)can also be demodulated when the coupling forms a slope detector.  RFI can also intermod with internal clocks forming new audible signals that are not related to audio.  So add that in with your description of noise.

I think by "choke" you're referring to the ferrite bead/chunk on some USB cables.  A few points on that.  It's not actually a simple "choke", but rather it contains R, L and C, and is a resonant circuit.  Every bead has a peak impedance frequency, in and of itself.  However, it also interacts with the rest of the circuit it's installed on, the result being a particular impedance response curve that may or may not help with a particular RFI situation. In fact, there are some conditions where the bead actually makes things worse.  It wouldn't be correct to say that the bead affects any current change in the cable, though, and it doesn't necessarily adversely affect timing or signals. It entirely depends on how the entire circuit is tuned.   It's not that ferrites should be avoided, it's that they should be properly applied to the total design.  Proper application requires full knowledge of the entire circuit.  I'm not sure how carefully that's done on a USB cable. 

You mentioned Ethernet...an Ethernet interface is essentially a set of balanced line receivers with common-mode filter.  It has to be, most Ethernet cables are unshielded twisted pair, so for that sort of interconnect to transmit uncorrupted data it must have extensive CMRR.  Using shielded Cat5/6 may help, but may also create a ground loop if the shield is grounded at both ends.  Typically the switch should be grounded, the devices not.  It's still a point of RFI entry, but probably minimal.  Coax would be a ground loop possibility too because the shield grounded at both ends and the signal is carried unbalanced.


----------



## gregorio

Clive101 said:


> Perhaps I should had been more detailed with my question, in a domestic situation when you listen with your trained ear and expertise you would notice noise to a greater extent than for example me. Buy what you say it's a yes !



Probably but you're missing the point! Both of us would hear the noise on the recording and/or from the audio system far more clearly in a well isolated studio. The higher the noise of the listening environment, the less you will notice and be able to identify the noise from your system, hence why we spend so much time and money isolating our studios in the first place! This is the exact opposite of what you have suggested, that somehow system noise would be more noticeable in an environment with a higher noise floor.



pinnahertz said:


> I think part of the confusion here is that galvanic isolation is all that is required for perfect RF immunity.  It's one method, a good one, you just can't use it for everything, and there are many possibly entries for RF.



Your knowledge of EE is obviously superior to mine but my point throughout much of this thread has been the marketed implication and understanding of some audiophiles that within a DAC, RF/EM and system/source noise is effectively impossible to isolate against to levels below audibility. My knowledge of EE and the specific designs of audiophile DACs is insufficient to counter this understanding with technical arguments and probably wouldn't help any way, as those I've been communicating with would not appreciate it, so I've attempted to use simple logic instead. Namely, how come pro audio DACs, even cheap ones, routinely manage a level of isolation which is apparently impossible for audiophile DACs costing far more? In many/most cases, I believe the differences heard by some audiophiles between USB cables is purely the result of a perception bias but there are some audiophile devices out there which are poorly enough designed to allow interference through to audible levels. In fact, I myself have heard an audiophile DAP which produced audible noise when positioned within a few inches of a laptop, noise which was rendered inaudible by an audiophile USB cable (or by moving it further away from the laptop). My response to this scenario is not that audiophile USB cables are therefore valid but that some audiophile devices are effectively faulty, designed with inappropriate isolation. If an audiophile USB cable really does make an audible difference, it's because it's providing a level of isolation which the DAC itself should be providing.

G


----------



## gregorio

theorist said:


> If an $80 Pro DAC, regardless of how it looked, sounded as good as a mega-dollar DAC, like a Dave, don't you think that market rationality would prevail ... But of course we don't because the (likely) accurate analytical sound the $80 Pro DAC produces, while fine for commercial studio mixing, etc, does not sound anywhere near as 'good' to the consumer's ears for enjoyable musicality as does the Dave ... This similar logic applies to generic and dedicated audio USB cables as well.



An unfortunately typical argument. If an $80 pro DAC produces accurate sound then it is high fidelity, if you are looking for a system which produces a different sound then you're looking for a less accurate system with lower fidelity. If we apply "this similar logic" to USB cables, you have or are going to spend a large sum of money on an audiophile USB cable in order to lower the fidelity of your system?! Regardless of any technical details/issues, the logic or "market rationality" you mention is neither logical nor rational! And, if we do consider the technical details/issues, the situation becomes even more nonsensical because to achieve this more "enjoyable musicality" would require the USB cable to contain either: A more "enjoyable musicality" algorithm (which doesn't exist) and the processing power to execute it. OR, A "musicality" pixie or some other magical/inexplicable property.

G


----------



## Leo-

pinnahertz said:


> I'd add a few to your two types.  Demodulated RFI can be audible on its own.  I live 5 miles from a 50kW directional AM station in the main lobe, for example.  That RF gets demodulated everywhere that's not had some form of RFI protection, and you get to hear the station in full fidelity.   FM signals (broadcast or 2-way)can also be demodulated when the coupling forms a slope detector.  RFI can also intermod with internal clocks forming new audible signals that are not related to audio.  So add that in with your description of noise.
> 
> I think by "choke" you're referring to the ferrite bead/chunk on some USB cables.  A few points on that.  It's not actually a simple "choke", but rather it contains R, L and C, and is a resonant circuit.  Every bead has a peak impedance frequency, in and of itself.  However, it also interacts with the rest of the circuit it's installed on, the result being a particular impedance response curve that may or may not help with a particular RFI situation. In fact, there are some conditions where the bead actually makes things worse.  It wouldn't be correct to say that the bead affects any current change in the cable, though, and it doesn't necessarily adversely affect timing or signals. It entirely depends on how the entire circuit is tuned.   It's not that ferrites should be avoided, it's that they should be properly applied to the total design.  Proper application requires full knowledge of the entire circuit.  I'm not sure how carefully that's done on a USB cable.
> 
> You mentioned Ethernet...an Ethernet interface is essentially a set of balanced line receivers with common-mode filter.  It has to be, most Ethernet cables are unshielded twisted pair, so for that sort of interconnect to transmit uncorrupted data it must have extensive CMRR.  Using shielded Cat5/6 may help, but may also create a ground loop if the shield is grounded at both ends.  Typically the switch should be grounded, the devices not.  It's still a point of RFI entry, but probably minimal.  Coax would be a ground loop possibility too because the shield grounded at both ends and the signal is carried unbalanced.



I mostly agree with you indeed. Audible RF noise to me could also fall into these two categories. It may be audible in itself and additionally it may change the signal by affecting the circuits, but also may be signal independent. Example is a guy who lived near a powerful radio antenna and his vinyl tonearm was a perfect antenna which let him listen to the radio while listening to vynil. Neat, isn't it?

Yes I meant ferrites and I also meant it affects all current changes. It is correct that they have optimal frequencies, however it doesn't mean that there are no induced currents in other cases (they're just not efficient filters for these conditions). You're absolutely right about ethernet cables, Im using a 5e and haven't noticed differences with respect to unshielded cable but some have noticed the shields shorted and generating ground loops.


----------



## Arpiben (Oct 13, 2017)

Shielded cables have typically both ends connected.
In some circumstances it may create ground loops.
If the shield is removed at one end only ( either at cable level or at device level ) you solution the ground loop but on the other hand you create an antenna.
When dealing with cables in the 1m length range you basically have an FM radio receiver.Then it may help increasing the length, etc....
Therefore there is no perfect solution until one understands which interferer is audible....

I found the following Jim Brown's document quite helpful: http://audiosystemsgroup.com/RFI-Ham.pdf


----------



## JaeYoon

gregorio said:


> An unfortunately typical argument. If an $80 pro DAC produces accurate sound then it is high fidelity, if you are looking for a system which produces a different sound then you're looking for a less accurate system with lower fidelity. If we apply "this similar logic" to USB cables, you have or are going to spend a large sum of money on an audiophile USB cable in order to lower the fidelity of your system?! Regardless of any technical details/issues, the logic or "market rationality" you mention is neither logical nor rational! And, if we do consider the technical details/issues, the situation becomes even more nonsensical because to achieve this more "enjoyable musicality" would require the USB cable to contain either: A more "enjoyable musicality" algorithm (which doesn't exist) and the processing power to execute it. OR, A "musicality" pixie or some other magical/inexplicable property.
> 
> G


So from what Theorist is saying does this mean if I buy a "Audiophile USB cable" and use it for connecting my laptop for company presentations, the sound will be musical! And the entire powerpoint will glitter and glow with musicality and warmth!!! 



Maybe if I also transfer a word document through these usb cables for work there might be some magic that will get the entire management to give me a raise on salary.


----------



## Niouke

I found this thread funny at first....at first.

Living In the current information age how is it possible to believe that bit perfect transmission is not possible over a pair of iron cords, or a cheap USB cable?
Just to put in perspective if you still use regular DSL line to access the internet, the HiRez FLAC files you download probably go througt a cabling that looks like this:







And yet they are bit perfect from the original, and you can probably also stream them on the fly, and they will still be bit perfect.

Also I ticked at the "noisy" computers assertion I've read here. If you think the noise inside a computer is big enough to corrupt a mere 5mb/s PCM stream, please consider that the typical modern volatile memory (RAM) in a computer is able to transfer  ten *Gibabyte per second*, and bit perfect of course. If it's not bit perfect your get a nice blue screen (in windows at least). For reminder 10Gb represents > a single blueray layer.


----------



## Leo-

That's because you despite being in the information age you still don't get it mate 

There is no data corruption involved, and no audible noise as some members have suggested. In simple terms, changes due to radio frequency interference and current leakages that are transmitted through cables are the ones which affect the analog circuits in your system, the "bit perfectness of the information" is not an issue however the timings of the information packet transmissions do affect the sound too, since in digital audio time is also information, not only the bits!



Niouke said:


> I found this thread funny at first....at first.
> 
> Living In the current information age how is it possible to believe that bit perfect transmission is not possible over a pair of iron cords, or a cheap USB cable?
> Just to put in perspective if you still use regular DSL line to access the internet, the HiRez FLAC files you download probably go througt a cabling that looks like this:
> ...


----------



## bigshot

Like grounding issues, RF interference usually isn't subtle. If you don't experience any obvious problems, there isn't any reason to worry about it. If you do have these sorts of problems, you're unlikely to solve it by just going out and buying an audiophile cable. You've got to go further than that.


----------



## Arpiben

Since this thread is now in sound science let me try to correct a few things even if I risk to confuse some a bit more.
*Bit Perfect:*
In Digital Audio terminology it is only meaning that the original audio file data bits have not been modified by any process (EQ/Volume/Up or Down sampling/Etc...).
It does not mean or guarantee that the original digital audio file is delivered to DAC without any bit corruption at all.

*USB Digital Transmission:*

When transfering *non real time* digital files from A to B bulk transfer with CRC check is used. In case of true or false error detection the packet is resent.
With such the probability to have a corrupted bit is extremely low let us say around 1 out of 10exp15.

When transfering* real time* digital files isochronous transfers are used. In case of true or false error detection the packet *is not resent.*
With such the probability to have a corrupted bit is still extremely low but higher compared to bulk transfer.

When dealing with *USB compliant cables*, at worst (with minimum specifications) the probability to have a corrupted bit at maximum rate is around 1 out of 10exp12 (Terabit).


*A bulk transfer* is used to _reliably_ transfer data between host and device. All USB transfers carry a CRC (checksum) that indicates whether an error has occurred. On a bulk transfer, the receiver of the data has to verify the CRC. If the CRC is correct the transfer is acknowledged, and the data is assumed to have been transferred error-free. If the CRC is not correct, the transfer is not acknowledged and will be retried.

*Isochronous transfers* are used to transfer data in _real-time_ between host and device. When an isochronous endpoint is set up by the host, the host allocates a specific amount of bandwidth to the isochronous endpoint, and it regularly performs an IN- or OUT-transfer on that endpoint. For example, the host may OUT 1 KByte of data every 125 us to the device. Since a fixed and limited amount of bandwidth has been allocated, there is no time to resend data if anything goes wrong. The data has a CRC as normal, but if the receiving side detects an error there is no resend mechanism.

In conclusion no use to worry at all with data integrity whatever protocol is used for transfering. But in absolute there are differences how data is treated.
*


*


----------



## Niouke

wait are we speaking about digital or analog there cause in digital "radio interference" and "current leakage" is a non issue if the receptor received the bit issued...I believe that what you are saying is that a "dirty" digital signal will impact the analog output like a defective ground? Nonsense, the DAC chip will never in any case use the power from the DATA channel to perform the conversion, it will use a dedicated power line that should be of course clean fora good conversion.

the PCM experts will correct me but the timing information is contained in the data, and not the actual spacing of the bit transmission? in any case an audiophile cable will not provide a more stable frequency transmission, as any normal cable does not change characteristics from one second to another.


----------



## pinnahertz

gregorio said:


> Your knowledge of EE is obviously superior to mine but my point throughout much of this thread has been the marketed implication and understanding of some audiophiles that within a DAC, RF/EM and system/source noise is effectively impossible to isolate against to levels below audibility. My knowledge of EE and the specific designs of audiophile DACs is insufficient to counter this understanding with technical arguments and probably wouldn't help any way, as those I've been communicating with would not appreciate it, so I've attempted to use simple logic instead. Namely, how come pro audio DACs, even cheap ones, routinely manage a level of isolation which is apparently impossible for audiophile DACs costing far more? In many/most cases, I believe the differences heard by some audiophiles between USB cables is purely the result of a perception bias but there are some audiophile devices out there which are poorly enough designed to allow interference through to audible levels. In fact, I myself have heard an audiophile DAP which produced audible noise when positioned within a few inches of a laptop, noise which was rendered inaudible by an audiophile USB cable (or by moving it further away from the laptop). My response to this scenario is not that audiophile USB cables are therefore valid but that some audiophile devices are effectively faulty, designed with inappropriate isolation. If an audiophile USB cable really does make an audible difference, it's because it's providing a level of isolation which the DAC itself should be providing.
> 
> G


I agree that audiophile devices may be poorly designed, and that they may indeed produce audible noise from various sources.  Sure, if a USB cable produces a positive difference it's providing a solution, albeit a band-aid that shouldn't have been necessary in the first place.  I was simply objecting the blanket "chokes are bad" statement.  Chokes/ferrites are not bad or good, they are a circuit element that needs to be properly applied if the goal is improvement.  

A also firmly believe that most percieved improvements are the result of expectation bias.  I have yet to see a properly performed, bias controlled test with sufficient statistical data, though I have little desire to search deeply.


----------



## Leo-

Niouke said:


> wait are we speaking about digital or analog there cause in digital "radio interference" and "current leakage" is a non issue if the receptor received the bit issued...I believe that what you are saying is that a "dirty" digital signal will impact the analog output like a defective ground? Nonsense, the DAC chip will never in any case use the power from the DATA channel to perform the conversion, it will use a dedicated power line that should be of course clean fora good conversion.
> 
> the PCM experts will correct me but the timing information is contained in the data, and not the actual spacing of the bit transmission? in any case an audiophile cable will not provide a more stable frequency transmission, as any normal cable does not change characteristics from one second to another.



Well... many DACs ARE powered by USB, and a fairly high current (1A or more) has to pass through the same cable which in itself creates interference. Best practice is to completely remove the +5V from the cable, but how many people do this? 

USB has no timing information. In theory the time signal information can be reconstructed at the DAC end knowing that the data packets are supposed to be synchronous, however again very very few DACs do this (requires buffering, a processor, good clocks, a little bit of engineering, etc). Typically the signal is either received "as is" from the source clock or the clocking can be slaved to the DAC, however the packet is then sent for decoding without further corrections.

It's the "should be" that kills it all... reality is more deceiving than theory would suggest.


----------



## bigshot

In practice USB works perfectly unless something is wrong with the basic design. I push music across my wifi network and theoretically that creates timing error, but in practice, it's totally inaudible.


----------



## Leo-

How do you know?


----------



## bigshot

I did A/B comparison between the source CD and the output over my Airport network.


----------



## castleofargh

Niouke said:


> wait are we speaking about digital or analog there cause in digital "radio interference" and "current leakage" is a non issue if the receptor received the bit issued...I believe that what you are saying is that a "dirty" digital signal will impact the analog output like a defective ground? Nonsense, the DAC chip will never in any case use the power from the DATA channel to perform the conversion, it will use a dedicated power line that should be of course clean fora good conversion.
> 
> the PCM experts will correct me but the timing information is contained in the data, and not the actual spacing of the bit transmission? in any case an audiophile cable will not provide a more stable frequency transmission, as any normal cable does not change characteristics from one second to another.


what some people fear here is noise somehow creeping in the circuit board and whatever impact that could have. delayed trigger of the 0/1 switch, noise passing into the analog circuit, like when coming from the the power source... pretty much all the stuff that are expected to be crazy small even in consumer level systems. except that here we're discussing with people who strive to get the very best possible. or at least like to think they do, because once again pretending to incrementally improve fidelity without measuring anything, that's one hell of a concept. one I don't get. 
in any case, the mentality is different because instead of thinking "low enough not to bother" like I would do, some are thinking "can it be improved, no matter how low it already is?"  it's a different world view and a different quest. there is nothing wrong with people who wish to achieve excellence. too bad audiophiles rarely wish to achieve excellence in logical reasoning, fact checking, and measurements. then this topic might lead somewhere.


----------



## Leo-

castleofargh said:


> pretty much all the stuff that are expected to be crazy small even in consumer level systems. except that here we're discussing with people who strive to get the very best possible. or at least like to think they do, because once again pretending to incrementally improve fidelity without measuring anything, that's one hell of a concept. one I don't get.
> in any case, the mentality is different because instead of thinking "low enough not to bother" like I would do, some are thinking "can it be improved, no matter how low it already is?" .



I think I will disagree with the "low enough" bit. Some equipment will never show differences between sources, bad and good recordings, swapping out equipment, audio formats and so on. In others, the differences jump to the listener's ears. The listening test is the ultimate one if the differences are sufficiently evident - one may not be able to tell which one is better, but at least can identify that a change is there. Measurements of currents, jitter, ground voltages... those things are incredibly difficult to measure, and how much do they tell you quantitatively? Sometimes not much. 

Just to illustrate? I have the same file in different formats, all from the same studio master (and provided by the studio man himself). I play them in one DAC, they all sound the same. I play them in the second DAC - night and day difference. Does this mean it makes audio formats make a difference of not? What's the answer to the question "do audio formats matter?" Finally, is that a measurement? Just food for thought...


----------



## pinnahertz (Oct 13, 2017)

castleofargh said:


> ...the mentality is different because instead of thinking "low enough not to bother" like I would do, some are thinking "can it be improved, no matter how low it already is?"  it's a different world view and a different quest.


What science is attempting to define is the threshold of "low enough not to bother".  It is, unfortunately, not just a threshold or a number but a complex multi-dimensional array that is in some cases not yet fully defined.


Leo- said:


> I think I will disagree with the "low enough" bit. Some equipment will never show differences between sources, bad and good recordings, swapping out equipment, audio formats and so on. In others, the differences jump to the listener's ears. The listening test is the ultimate one if the differences are sufficiently evident - one may not be able to tell which one is better, but at least can identify that a change is there.


*All part of the above.  The listening conditions affect the audibility threshold.  True enough, but that doesn't mean there isn't one. 
*


Leo- said:


> Measurements of currents, jitter, ground voltages... those things are incredibly difficult to measure, and how much do they tell you quantitatively? Sometimes not much.


Huh?  Currents, jitter, ground voltages, noise, distortion, response, temporal response...all are now easily measured and quantified.  The task, as I've said, is correlation to the audible.  The error is to try to assign a single figure or two-axis data point. That doesn't mean audible correlation is impossible, just a much bigger task.  But measurement itself is a done deal.


Leo- said:


> Just to illustrate? I have the same file in different formats, all from the same studio master (and provided by the studio man himself). I play them in one DAC, they all sound the same. I play them in the second DAC - night and day difference. Does this mean it makes audio formats make a difference of not? What's the answer to the question "do audio formats matter?" Finally, is that a measurement? Just food for thought...


Not much food for thought, though, other than....it's another example of an opinion with zero information and no statistics.  No equipment specified, no information on playback conditions, hardware, connection, environment, and it's the fully sighted and biased opinion of one guy.

I'm not trying to invalidate the above as your opinion, it is valid as such, but it's not an indication of anything other than your opinion, one that does not invalidate or validate anything about formats, interconnects, or system performance.  It's an opinion, not a data point.


----------



## bigshot (Oct 13, 2017)

Leo- said:


> Just to illustrate? I have the same file in different formats, all from the same studio master (and provided by the studio man himself). I play them in one DAC, they all sound the same. I play them in the second DAC - night and day difference. Does this mean it makes audio formats make a difference of not? What's the answer to the question "do audio formats matter?"



Well, that is really easy to figure out. If what you say is true and assuming all the formats should be audibly transparent, one DAC is properly presenting all of the formats as the same sound, and the other isn't presenting some of them properly. There are a million ways to mess up sound, but only one way to get it right. Audibly transparent should be audibly transparent. As long as it is, it's fine for the purposes of listening to music in the home. If it was me, I'd send the one that is making them all sound different back for a refund. It's clearly defective.


----------



## Leo-

Huh?  Currents, jitter, ground voltages, noise, distortion, response, temporal response...all are now easily measured and quantified.  The task, as I've said, is correlation to the audible.  The error is to try to assign a single figure or two-axis data point. That doesn't mean audible correlation is impossible, just a much bigger task.  But measurement itself is a done deal.

Not much food for thought, though, other than....it's another example of an opinion with zero information and no statistics.  No equipment specified, no information on playback conditions, hardware, connection, environment, and it's the fully sighted and biased opinion of one guy[/QUOTE]

It is certainly easy to take measurements, to make meaningful ones it is not so much. I'll disagree with you on that one. Anyways, how many here have access to lab grade oscilloscopes and know how to get meaningful ffts and so on? Not so many I'd guess.

Anyhow, don't take my comment as nothing more than a data point. In reality I mentioned this because it's something I'm working on but I still need to do comparisons, take measurements and eliminate variables, but I'll be happy to share the link when it's done. However, if done carefully it's a data point. My conclusions may or may not apply to you, but according to the scientific method seeing no difference in something doesn't prove that no difference may exist - only if you rule out all possibilities you can claim that. On the other hand, to prove that a difference may exist it is enough to find one and only one case!


----------



## pinnahertz

Leo- said:


> It is certainly easy to take measurements, to make meaningful ones it is not so much. I'll disagree with you on that one.


You must be working with a unique and individual definition of "measurement" then.  We work with standard units, volts, amps, watts, dB ratios, Hz, seconds...what about that is not meaningful?


Leo- said:


> Anyways, how many here have access to lab grade oscilloscopes and know how to get meaningful ffts and so on? Not so many I'd guess.


I'm not going to guess, but anyone trying to make a scientific statement at least can reference someone's work who does have access to that equipment.  (I am smiling...just a bit...about "lab grade oscilloscopes"...funny.)


Leo- said:


> ...according to the scientific method seeing no difference in something doesn't prove that no difference may exist - only if you rule out all possibilities you can claim that.


ok....


Leo- said:


> On the other hand, to prove that a difference may exist it is enough to find one and only one case!


Nope! That would closer to trying to define "margin of error".


----------



## bigshot

Leo- said:


> On the other hand, to prove that a difference may exist it is enough to find one and only one case!



And the validity would depend on how badly you wanted that result and what kind of slack controls you employed to allow you to reach your goal.


----------



## castleofargh

Leo- said:


> I think I will disagree with the "low enough" bit. Some equipment will never show differences between sources, bad and good recordings, swapping out equipment, audio formats and so on. In others, the differences jump to the listener's ears. The listening test is the ultimate one if the differences are sufficiently evident - one may not be able to tell which one is better, but at least can identify that a change is there. Measurements of currents, jitter, ground voltages... those things are incredibly difficult to measure, and how much do they tell you quantitatively? Sometimes not much.
> 
> Just to illustrate? I have the same file in different formats, all from the same studio master (and provided by the studio man himself). I play them in one DAC, they all sound the same. I play them in the second DAC - night and day difference. Does this mean it makes audio formats make a difference of not? What's the answer to the question "do audio formats matter?" Finally, is that a measurement? Just food for thought...


I'm not against listening feedback, I wouldn't waste my time learning and discussing ABX and other listening methods and the best way to volume match some gears if I saw no value in listening impressions. if anything listening impressions are a very good to notice if something seems wrong. it will gives the idea to investigate and make sure.  I'm only against mistaking listening impressions for a high fidelity measurement tool. most variables can be checked for fidelity magnitudes better than what hearing could hope to achieve, it's plain wrong to assume that they're equivalent methods or worst, that hearing is superior. and that's even before bringing up all the biases, preconceptions and placebo effects.

and to be clear, I was talking about people who aim at getting better *fidelity*. the tuning of music with USB cable is crazy talk to me I don't even want to participate in such a conversation. and all those who only care about their personal preferences need nobody else to make a decision. different approaches for different purposes.

about anecdotes, let's go straight to the top, you can find anecdotes about how some famous DAC designers were hearing something but couldn't find any issue in measurements. much more credible than some noname guy on the web. the advantage with anecdotes, you only need for things to happen once by accident to have some impressive stories for the rest of your life. even Shiit has one of those stories. but realistically, how often do you figure that happens, something clearly noticeable(under controlled listening!!!!!!!!!) but eluding measurements completely? and what do you think it leads to? the guy going "ok so my hearing is superior I don't need measurements", or the guy trying to develop a reliable procedure to confirm objectively what's potentially a problem he didn't think about? you know like how every single measurement method was born. ^_^ 
those anecdotes that people love to misuse as evidence that human hearing is important in testing, IMO they are all testimonies to the lack of proper measurement and methods(for various reasons, laziness, rig too expensive, pioneering in a domain and having to make the tools as we advance...). but they do not convince me that I should trust my ears more.
because how easy is it to fool people into making up impressions of audible differences in sighted tests, simply by changing the price tag, the look, or the marketing of the same cable? we can fool pretty much anybody and we know it for we tried so many times. fidelity assessment through sighted test... yeah funny. and expecting others to just trust someone's impressions and conclusions based on those impressions without any sort of evidence, IMO that's not funny, that's gullibility. but I guess that's why I hang out mostly in this section of the forum(aside from doing bad police job from time to time).


----------



## Leo-

pinnahertz said:


> You must be working with a unique and individual definition of "measurement" then.  We work with standard units, volts, amps, watts, dB ratios, Hz, seconds...what about that is not meaningful?
> I'm not going to guess, but anyone trying to make a scientific statement at least can reference someone's work who does have access to that equipment.  (I am smiling...just a bit...about "lab grade oscilloscopes"...funny.)
> ok....
> 
> Nope! That would closer to trying to define "margin of error".



Funny that you chuckle on the oscilloscope reference but then suggests that a measurement is a measurement. Before taking any measurement you have to be sure that you're doing the right thing, which requires that you actually understand what you're doing. Like those kids who take a $40 oscilloscope and measure the THD of a $20 class D amp. They measure 0.00001% and conclude it's perfect! But their oscilloscope have 20MHz bandwith and the amp they're trying to measure uses 1.5MHz pulses. The _minimum_ error of their measurement is about 2%! There are plenty of rubbish measurements posted on the internet even by professional reviewers. In another forum, someone noticed something strange on the results of reclockers published in a popular website. When inquired, the author explained what he did and it turned out it was all complete nonsense. On the other side, there are some very good people out there publishing good things. So you have to do your own due diligence before believing in any results. 

ps. you're probably not familiar with the concept of proof by contradiction of absurd. If you want to prove that a statement is right (e.g. all blonde people are dumb) and you find ONE sound case where the statement doesn't hold (e.g. Einstein was blonde and hell yeh he was intelligent), then your premise MUST be wrong (i.e. most blonde people may be dumb, but some are intelligent). 

ps2. I've only seen Einstein photos with white hair. How intelligent is Pamela Anderson? 

@castleofargh agreed, especially about _fidelity _(and honestly, I've seen something about these expensive "tuning" audio cables - utter rubbish). That's something hard to tell especially in light of the sound artificts that I mentioned before. My comment was intended to be on the side of logic (i.e. assume that this is correct -> then what happens?), I didn't imagine that would decrease the S/N ratio in the discussion but it seems it did.


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## pinnahertz

Leo- said:


> Funny that you chuckle on the oscilloscope reference but then suggests that a measurement is a measurement. Before taking any measurement you have to be sure that you're doing the right thing, which requires that you actually understand what you're doing. Like those kids who take a $40 oscilloscope and measure the THD of a $20 class D amp. They measure 0.00001% and conclude it's perfect! But their oscilloscope have 20MHz bandwith and the amp they're trying to measure uses 1.5MHz pulses. The _minimum_ error of their measurement is about 2%! There are plenty of rubbish measurements posted on the internet even by professional reviewers. In another forum, someone noticed something strange on the results of reclockers published in a popular website. When inquired, the author explained what he did and it turned out it was all complete nonsense. On the other side, there are some very good people out there publishing good things. So you have to do your own due diligence before believing in any results.


Um....well, you're not going to measure THD at all with any oscilloscope, not to .00001%, or even 2%....wrong tool.  And pulses aren't THD anyway, though they could be lumped into a THD+N measurement, we're pretty careful about separating that stuff now.   THD analyzers generally have a bandwidth of 0-100kHz, so, according to your comments above, even a lab-standard THD analyzer from the likes of Tektronix, HP/Agilent or AP would be wrong.  I don't think so.... 

But a lowly 20mHz scope would reveal any of the 1.5mHz pulses dribbling out of the output.  I'm not sure what your point is, other than even you are suggesting the wrong tools.  

My chuckle was at "lab grade oscilloscopes"...like it's even possible to buy a scope so awful that it wouldn't be useful for audio.  The $300 Chinese stuff at Fry's is just fine, and the $1000+ Tektronix stuff is also great (though the best deals on Tek gear is on the used market).  Mine's a Tek 100mHz  analog/DSO...but I couldn't possibly measure THD with it.  No one could. Wrong tool.


Leo- said:


> ps. you're probably not familiar with the concept of proof by contradiction of absurd. If you want to prove that a statement is right (e.g. all blonde people are dumb) and you find ONE sound case where the statement doesn't hold (e.g. Einstein was blonde and hell yeh he was intelligent), then your premise MUST be wrong (i.e. most blonde people may be dumb, but some are intelligent).


I don't think I know of any scientist who would be caught making the absurd argument to begin with.  We're all pretty familiar with the danger of making sweeping absolute statements, and other such things as margin of error.  

Now, marketing people...that's quite another story.


Leo- said:


> ps2. I've only seen Einstein photos with white hair. How intelligent is Pamela Anderson?


Poor kid.  Has all her hair gone white now?


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## theorist (Oct 14, 2017)

There is in no high fidelity, or absolute sound, in reproduced music. There may be a crude, so called ‘high fidelity’, defined by positivists and that you can crudely and pragmatically measure as sound by frequency response and a few other relatively easy to measure characteristics, but that does not truly measure the difficult to quantify characteristics of nuance, timing, timbre, ‘space between the notes’ and everything else that comprises the beauty of music. An $80 DAC or cheap generic USB cable may well fit in that positivistic paradigm of commercial recording of ‘high fidelity’, but most of us can readily hear this falsehood of its reproduction of so call perfect ‘high fidelity’ sound, hence we spend our hard-earned funds to buy better and more musically enjoyable equipment.


Moreover, so called expectation bias cuts both ways. If you believe that $80 DACs are perfect, or that $12 USB cables make no difference to a dedicated audiophile cable in transmitting the bits and all the parasitical noise that tries to goes with them, then your expectation bias will not hear any difference in DACs or USB cables that do so much better in conveying nuance, timing, timbre, ‘space between the notes’ and everything else that comprises the beauty of music. However, if you are not biased and have open ears/minds, and using reasonably quality equipment, perhaps you might hear this important difference.


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## pinnahertz

theorist said:


> There is in no high fidelity, or absolute sound, in reproduced music. There may be a crude, so called ‘high fidelity’, defined by positivists and that you can crudely and pragmatically measure as sound by frequency response and a few other relatively easy to measure characteristics, but that does not truly measure the difficult to quantify characteristics of nuance, timing, timbre, ‘space between the notes’ and everything else that comprises the beauty of music. An $80 DAC or cheap generic USB cable may well fit in that positivistic paradigm of commercial recording of ‘high fidelity’, but most of us can readily hear this falsehood of its reproduction of so call perfect ‘high fidelity’ sound, hence we spend our hard-earned funds to buy better and more musically enjoyable equipment.
> 
> 
> Moreover, so called expectation bias cuts both ways. If you believe that $80 DACs are perfect, or that $12 USB cables make no difference to a dedicated audiophile cable in transmitting the bits and all the parasitical noise that tries to goes with them, then your expectation bias will not hear any difference in DACs or USB cables that do so much better in conveying nuance, timing, timbre, ‘space between the notes’ and everything else that comprises the beauty of music. However, if you are not biased and have open ears/minds, and using reasonably quality equipment, perhaps you might hear this important difference.


So you're choosing to ignore a few things then? Like how it's impossible not to be biased even if we might think we have open minds, or that the recordings we all listen to via DACs of all sizes, shapes and costs, were made with unknown quality ADCs (some pretty cheap), in studios using unknown (but likely generic) cables in high noise environments?  You don't seem to be complaining of more than half the signal path, even though it's unknown and possibly the worst link of the chain relative to the short length of USB cable in a relatively noise-free home.  Or that, aside from your statement that, "There is in no high fidelity, or absolute sound, in reproduced music.", it can be readily shown that it is impossible for a trained listener to discern the difference between a live performance monitored on speakers vs the same mix passed through ADC and DAC of very rudimentary quality. 

I wonder what you might say to a true double-blind ABX test of...well, anything (not a single-blind test without significant data) where expectation bias is in fact actually removed.

But, since,"There is in no high fidelity, or absolute sound, in reproduced music", I guess the entire argument is moot. 

We can all give up now and go home.  Those of us in the pro audio business can just shoot ourselves and rid the world of our pervasive blight of low fidelity sound.  

(...or thus would I respond to the troll, if I were to respond to a troll....)


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## gregorio

Leo- said:


> [1] Measurements of currents, jitter, ground voltages... those things are incredibly difficult to measure, and how much do they tell you quantitatively?
> [2] ... according to the scientific method seeing no difference in something doesn't prove that no difference may exist - only if you rule out all possibilities you can claim that.
> [3] I have the same file in different formats, all from the same studio master (and provided by the studio man himself). I play them in one DAC, they all sound the same. I play them in the second DAC - night and day difference. Does this mean it makes audio formats make a difference of not? What's the answer to the question "do audio formats matter?"



Oh dear, so much audiophile myth in just a couple of posts, it's difficult to know where to start. I'll just deal with a few points which, with just a small amount of factual knowledge, should be obvious but do not seem to be, presumably due to marketing designed to take advantage of audiophile ignorance/assumption. 

1. How much do they tell you quantitatively? Effectively everything or, to put it another way, if there is something we can't measure/quantify then it's irrelevant. Just think about it logically for a moment, the audio recording/reproduction process is effectively the measuring/quantifying of sound wave properties, the conversion of those quantified values into other forms (electrical, magnetic, mechanical or in the case of digital, data) and then the conversion back again for reproduction. Therefore, even if audiophiles are correct and there is something we cannot measure or quantify, it's utterly irrelevant anyway because if we can't measure or quantify it, then we cannot record it in the first place and it does not exist on the recordings to which audiophiles are listening!!

2. While your statement is true, you are unfortunately lacking a vital piece of information/knowledge which means that it is INAPPLICABLE! There is a very old and widely used test, it's widely used precisely because it satisfies the scientific method and does exactly what you suggest, it rules out all other possibilities. It's called the "Null Test" and it does not require an oscilloscope, just basic (even free) audio software. If the result of a Null test is a null, then there definitively is no difference between two audio files/signals, with NO other "possibilities"! If the result is not null, then what we're left with is the difference between the signals/files and the magnitude of that difference can often easily be dismissed as below audibility. It's only when the magnitude of the difference (if there is one) reaches a level which *might* be audible that a listening test could be worthwhile.

3. Your two questions are an example of a very widely used audiophile marketing tool, the correlation fallacy. "I hear an audible difference when playing different formats therefore there must obviously be an audible difference between formats". At least in your case you are asking the question rather than making absolute statements of fact, which is a  very good start (!) but still, your questions indicate a correlation fallacy and additionally, contradicts other statements you have made (for example the statement quoted in point #2). Why are you asking if audio formats make a difference, have you "ruled out all [the other] possibilities" that the "night and day" difference you heard has anything directly to do with different audio formats in the first place? For example, have you ruled out the possibility that simply seeing that one audio format is marketed as "high definition" is causing you to perceive a difference where there is none or that the device you are using to playback those different formats is creating an audible difference when there is none?

The audiophile world is rife with the assertion that measurements (and science) doesn't tell us everything. When/If science is quoted, it's typically done so out of context, with missing information (which invalidates it in that context), is only applied to confirm an audiophile assumption and is conveniently ignored or dismissed when that exact same science is applied consistently and contradicts audiophile assumption.

Much of the above could imply that most audiophiles are just exceptionally stupid, gullible morons but that implication is not my intention! Sure, audiophiles are ignorant and have gaps in their factual knowledge but then so does everyone, music recording/reproduction covers a very wide range of scientific, engineering and artistic fields and no one is without some level of ignorance. The difficulty for audiophiles is that there is a great deal of money to be made from filling those "gaps in their factual knowledge" with marketing BS and little/no money to be made from filling them with the actual facts! With today's marketing techniques, one doesn't have to be a gullible moron to fall for it, it can be difficult to resist even for the highly intelligent but nevertheless, many of the audiophile beliefs, myths and assumptions break down quite quickly if one is willing to learn some actual facts and apply some logic.

G


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## Leo-

pinnahertz said:


> Um....well, you're not going to measure THD at all with any oscilloscope, not to .00001%, or even 2%....wrong tool.  And pulses aren't THD anyway, though they could be lumped into a THD+N measurement, we're pretty careful about separating that stuff now.   THD analyzers generally have a bandwidth of 0-100kHz, so, according to your comments above, even a lab-standard THD analyzer from the likes of Tektronix, HP/Agilent or AP would be wrong.  I don't think so....
> 
> But a lowly 20mHz scope would reveal any of the 1.5mHz pulses dribbling out of the output.  I'm not sure what your point is, other than even you are suggesting the wrong tools.
> 
> ...



Very funny. So you're saying it's impossible to measure distortion with an oscilloscope and the foundations of logic are flawed. That's why this thread is going nowhere.


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## sandab (Oct 14, 2017)

Arpiben said:


> *Isochronous transfers* are used to transfer data in _real-time_ between host and device. When an isochronous endpoint is set up by the host, the host allocates a specific amount of bandwidth to the isochronous endpoint, and it regularly performs an IN- or OUT-transfer on that endpoint. For example, the host may OUT 1 KByte of data every 125 us to the device. Since a fixed and limited amount of bandwidth has been allocated, there is no time to resend data if anything goes wrong. The data has a CRC as normal, but if the receiving side detects an error there is no resend mechanism


The main problem is that the sampling rate requires transmitting 1kB every 125us, but no clock is perfect.  The host might send every 124.75us.  A naive receiver which simply buffers and clocks out at 125us (which might be, say 125.10us) will eventually find itself starved with an empty buffer and you get a skip as it paused to let the host catch up.  This is why formats like AES/EBU embed the sample clock in the data stream, so the downstream component is effectively clocked by the upstream.  (This is also required to maintain lip sync for video.)  With the latter though clock recovery (the act of looking at the stream and locking a PLL to the embedded clock) is quite feasible, but how do you expect to recover clock from USB data packets?  There is no way for the receiver to know the actual sample playback rate is slightly high.  You can't lock a PLL to USB packets.  Clock recovery becomes MUCH more complicated and the only realistic method is to maintain a buffer and clock according to its fill rate.  Of course, larger buffers add latency and any algorithm used to recover the host clock based on a USB receive buffer is bound to have a bunch of pathological failure modes.  In reality of course timebases move around, and an hour later it could be the host sending packets every 125.10us and the device trying to clock it out effectively at 124.75us thinking it's actually doing so at a rate of 125.00us per 1kB.  This will result in buffer overrun, unless the receiver has an infinite buffer, and overrun will invariably result in some audible artifact.  Clock recovery in USB playback is simply an intractable problem.  Asynchronous playback solves this with flow control; the receiver plays at whatever actual rate it wants and simply tells the host when it reaches a low-water mark, asking it to refill to high-water.  The host doesn't clock anything at all.  This, though, in turn makes video lip sync a challenge.


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## Arpiben

sandab said:


> The main problem is that the sampling rate requires transmitting 1kB every 125us, but no clock is perfect.  The host might send every 124.75us.  A naive receiver which simply buffers and clocks out at 125us (which might be, say 125.10us) will eventually find itself starved with an empty buffer and you get a skip as it paused to let the host catch up.  This is why formats like AES/EBU embed the sample clock in the data stream, so the downstream component is effectively clocked by the upstream.  (This is also required to maintain lip sync for video.)  With the latter though clock recovery (the act of looking at the stream and locking a PLL to the embedded clock) is quite feasible, but how do you expect to recover clock from USB data packets?  There is no way for the receiver to know the actual sample playback rate is slightly high.  You can't lock a PLL to USB packets.  Clock recovery becomes MUCH more complicated and the only realistic method is to maintain a buffer and clock according to its fill rate.  Of course, larger buffers add latency and any algorithm used to recover the host clock based on a USB receive buffer is bound to have a bunch of pathological failure modes.  In reality of course timebases move around, and an hour later it could be the host sending packets every 125.10us and the device trying to clock it out effectively at 124.75us thinking it's actually doing so at a rate of 125.00us per 1kB.  This will result in buffer overrun, unless the receiver has an infinite buffer, and overrun will invariably result in some audible artifact.  Clock recovery in USB playback is simply an intractable problem.  Asynchronous playback solves this with flow control; the receiver plays at whatever actual rate it wants and simply tells the host when it reaches a low-water mark, asking it to refill to high-water.  The host doesn't clock anything at all.  This, though, in turn makes video lip sync a challenge.



Correct.  Most DACs nowadays, if not, at least those involved in the current discussion, are working in USB Asynchronous Transfer Mode.
Dealing with latency issues (lip sync), the main contributor is the multitap interpolation FIR (when used) rather than the input data buffer size, no?


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## gregorio

theorist said:


> There is in no high fidelity, or absolute sound, in reproduced music. There may be a crude, so called ‘high fidelity’, defined by positivists and that you can crudely and pragmatically measure as sound by frequency response and a few other relatively easy to measure characteristics, but that does not truly measure the difficult to quantify characteristics of nuance, timing, timbre, ‘space between the notes’ and everything else that comprises the beauty of music.



You've made this argument before, it's typical audiophile nonsense based on the confusion between quantity and quality. That confusion is forgiveable in many audiophiles, especially with so much marketing material deliberately designed to propagate and benefit from that confusion but it is INCONCEIVABLE in someone who claims to be a university professor in the field of the philosophy of science?!

Quantity is the amount or number of something, in the case of audio; frequency and amplitude, which can be very accurately measured (and quantified) using universally accepted units designed specifically for the task; Hertz (Hz), cycles per second and dB, decibels, for example. Quality on the other hand is not a physical property, it is a purely human perception/judgement, it cannot be measured or quantified, there is no unit of measurement for it and the very best which can be achieved is a very vague, general consensus of human judgement/opinion. As I explained to @Leo-, we can only record what we can measure/quantify, if we can't measure or quantify it then we cannot record it! Nuance and "everything else that comprises the beauty of music" are *qualities*, they cannot be measured/quantified and therefore CANNOT be recorded! The only thing we can record is frequency and amplitude but of course we can choose which frequencies and amplitudes we record and, as we are human beings, we can base our choice of frequencies and amplitudes on what we perceive (judge to have quality, nuance and beauty) or, in the case of professionals, on what we believe other human beings will hopefully perceive.

In short, your descriptions of nuance, beauty and even the term "music" itself are quality judgements of human perception, not physical properties of sound and therefore not properties of recordings or the reproduction of them! Nowhere is this confusion between quantity and quality more evident in the audiophile world than in the term "Fidelity". Fidelity is the faithfulness/accuracy of a piece or pieces of equipment to reproduce an input signal (frequencies and amplitudes), effectively a comparison of input frequencies and amplitudes vs output frequencies and amplitudes which can of course be measured and quantified. However, many in the audiophile world seem to think that "fidelity" is a quality rather than a quantity, that if some bit of kit is perceived as sounding good or better than an equivalent bit of kit then it has higher fidelity. There is no direct correlation between quantity and quality and this is why we often see the exact same (or even lower) fidelity being perceived by audiophiles as better and then erroneously describing it as higher fidelity. Vinyl vs digital being just one of numerous such examples.

The opening sentence that I've quoted above is therefore not just nonsense, it's the exact opposite of reality. There is high and low fidelity (different degrees of accuracy) and absolute sound is the ONLY thing in recorded and reproduced music! How you've arrived at your conclusion and state it so absolutely and confidently is, I suppose, testament to the effectiveness of audiophile marketing!

G


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## pinnahertz

Leo- said:


> Very funny. So you're saying it's impossible to measure distortion with an oscilloscope and the foundations of logic are flawed. That's why this thread is going nowhere.


It IS impossible to measure distortion with an oscilloscope!  If you think otherwise, then state your method!

I didn't say anything about the foundations of logic in general, I said YOUR logic is flawed.


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## gregorio

sandab said:


> This is why formats like AES/EBU embed the sample clock in the data stream, so the downstream component is effectively clocked by the upstream. (This is also required to maintain lip sync for video.)



While I agree with most of your post, it's not related to video/audio sync. A/V sync can be quite a complex subject but to massively simplify; there is no AES/EBU sample clock in video and therefore no direct way to sync audio to video. The most common/accurate method of achieving it in the first place is to have an external master-clock generating a video speed reference (black-burst or tri-sync). This clock signal is fed into the video card which regulates it's clock accordingly and into a sync unit which, using PLL or similar schemes, regulates a sample clock for use by the ADC/DACs, we now have picture and sound regulated to exactly same speed by use of exactly the same clock source. In addition, we have SMPTE Time-Code which provides the positional reference and the end result is hopefully what is called "frame-edge sync-lock". Once sync-locked during creation, something fairly serious has to go wrong during consumer playback in order loose lip-sync. Clocking inaccuracies in any vaguely competent DAC would not be enough to account for the loss of lip-sync.

G


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## Leo-

pinnahertz said:


> It IS impossible to measure distortion with an oscilloscope!  If you think otherwise, then state your method!
> 
> I didn't say anything about the foundations of logic in general, I said YOUR logic is flawed.



Sure, that's basic stuff. THD is simply the relative power of the harmonics of the reference signal. Inject the signal at the input, add up the power of the harmonics, measure the RMS power of the signal itself and calculate the ratio between the equivalent RMS voltage of the harmonics to the RMS voltage of the signal itself. This way the influence of noise is also elliminated. I found a neat old school manual to illustrate how to do that with an old school oscilloscope (the cover is a piece of art in itself  ):

http://lcweb2.loc.gov/master/mbrs/r...ektronix Cookbook of Standard Audio Tests.pdf

Now why is my blonde logic flawed aside from the fact that Eistein may not have been blonde after all (maybe all white haired people are intelligent by definition)?


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## pinnahertz

Leo- said:


> Sure, that's basic stuff. THD is simply the relative power of the harmonics of the reference signal. Inject the signal at the input, add up the power of the harmonics, measure the RMS power of the signal itself and calculate the ratio between the equivalent RMS voltage of the harmonics to the RMS voltage of the signal itself. This way the influence of noise is also elliminated. I found a neat old school manual to illustrate how to do that with an old school oscilloscope (the cover is a piece of art in itself  ):
> 
> http://lcweb2.loc.gov/master/mbrs/recording_preservation/manuals/Tektronix Cookbook of Standard Audio Tests.pdf


Yes, I understand what THD is.  That's never been the question.  _Now tell me how to measure it with an oscilloscope._


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## Leo- (Oct 14, 2017)

I just did?

ps. I hope you're not nitpicking about the semantic difference between oscilloscopes vs. spectrum analysers. I've never used an old style 'oscilloscope' that doesn't have FFT mode, but then I don't know how old are you...


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## pinnahertz (Oct 14, 2017)

Leo- said:


> I just did?


Ah.  I see the problem now. You don't understand what an oscilloscope is and what it does.  It presents a graphical representation of _voltage vs time, _but that's all.  It will display the complete waveform, voltage on the Y axis, time on the X axis.  Unless you have some superhuman ability to perform a visual FFT on that waveform there is no way you can determine the relative power of the harmonics, or the RMS value of the waveform.
The manual you linked to came with the Tek 5L4N, a low frequency spectrum analyzer plugin.  I know the device quite well, used it extensively in it's heyday.  It's NOT an oscilloscope at all, it just uses one to present its results.   You can't actually buy that device in any form today.  It used a rather complex means to sweep a narrow bandwidth filter across portions or all of the audio band, and presented a logged dB display.  The part of the scope that was essential was it's analog storage capability.  The spectrum analyzer took many seconds to sweep the entire band, presenting its results as frequency on the X axis, and signal amplitude on the Y axis. But, since the process took time (if you learn the theory of swept spectrum analysis, bandwidth vs time response, this becomes clear) the scope only presents a slowly moving do the dot on the front of the CRT wouldn't end up showing you anything unless the scope had storage capability.  That scope used a very old analog method to do that.  The resulting display was ok, but lacked contrast, and you had to take a Poloroid photo of the screen with one of the Tek scope cameras (yes, had that too), to maintain a record of your results.  It had issues too, like the internal log amp drifted, the extreme low frequency resolution was poor, and 20Hz calibration drifted with temperature.  It was still useful, but for THD it was surpassed by Tek's AA501 THD analyzer (look that one up and learn some more), which let us input a sine wave and get an actual THD+N figure in a second or so, also providing weighting and band limiting filters and an output that you could monitor to see if the reading was made up of harmonics or contained noise.

The 5L4N is a Low Frequency Spectrum Analyzer, _*not an oscilloscope!*_  Study up, know the difference.

Now, I think perhaps someone needs to stop making sweeping technical statements about things of which he lacks any clear understanding, like audio measurement, for example.

edit: nice edit you made while I was typing this.  It doesn't matter, if you actually knew the difference you'd never have claimed you can measure THD with a scope. So you read your link, huh?  The difference between a scope and spectrum analyzer is hardy semantic.


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## Leo-

Well, ok - at least now I understand you're picking up on the semantics not the physics. No need to be unapologethic though - I've said it wrong in the past and I'm sure it's not the last time. I already said this to our instrumentation guys at work and they get quite pissed off too ("don't call my expensive instrument a freaking oscilloscope you uneducated person!" is a classic one). Thanks for the stories nevertheless, I actually work with very complex and expensive instrumentation but not on the electronics side. 

However I've never seen people taking pictures of SA screens, definitely not something from my time. Oldest SA that I've operated was from the 70's in an old analog flight simulator but it was quite easy to read the numbers off the screen. Not that easy was to convert the aircraft stability modes to circuit gains - at university I actually had an enthusiast professor who teached us how to make these electronic analogies, but that's another lost art that nobody will ever need anymore. 

What were we talking about?


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## bigshot (Oct 14, 2017)

theorist said:


> There is in no high fidelity, or absolute sound, in reproduced music.



A philosopher!

I read your post three times trying to figure out what kind of DAC I should buy, and I couldn't parse anything out of it except "There are more things in heaven and Earth than are dreamt of in your philosophy." That really doesn't help me much. Some specific technical info and objective tests might help me make a better decision. Philosophers don't make the best advisors when it comes to putting together a stereo system. Poets don't make great audio equipment reviewers either, but a lot of them seem to be taking up the trade. I'll stick with scientists for judging electronics.

I'm curious why this thread was moved to Sound Science. There are people in it who aren't talking at all about Sound Science. If it was veering off topic at one time for the woo woo cable forum, I think we can agree it's veering off topic for Sound Science now. Maybe the thread should be marked "return to sender".


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## Arpiben

Good methodology and a basic oscilloscope is enough to track eventual audible interferers.
No use of any Tektronix/Keysight (Agilent before) digital scope sampling at 5GSps with all options (FFT/Spectogram/etc...).
Those may be use by designers for tracking EMI.
In some cases 'old analog' measurements are more efficient in tracking defects, VSWR in waveguides for example.
@pinnahertz is perfectly right and this applies not only to audio.


----------



## Leo-

Just few months ago I found an even more basic issue. Some guys came by to complain about some strange "vibrations" which I had never noticed before. Their results looked physically impossible to me, so I compared the output of the software to my routines for some perfect example signal. Bingo - turns out the instrumentation software had a gross bug that was never noticed before. Scary stuff - dozens of companies use the same software. 

@pinnahertz  actually there may would be a way to get RMSs from old oscilloscopes using your pre-historic method. In the old times before computers were widespread, people would get integral estimates by plotting graphs in heavy paper, carefully cut around the silhouettes and weigh them with a precise scale against a reference. This could be done with the polaroid of the output signal - knowing the amplifier gain and doing the same for the input signal, the fundamental frequency could be subtracted. Useless but funny.


----------



## Arpiben

Leo- said:


> Just few months ago I found an even more basic issue. Some guys came by to complain about some strange "vibrations" which I had never noticed before. Their results looked physically impossible to me, so I compared the output of the software to my routines for some perfect example signal. Bingo - turns out the instrumentation software had a gross bug that was never noticed before. Scary stuff - dozens of companies use the same software.
> 
> @pinnahertz  actually there may would be a way to get RMSs from old oscilloscopes using your pre-historic method. In the old times before computers were widespread, people would get integral estimates by plotting graphs in heavy paper, carefully cut around the silhouettes and weigh them with a precise scale against a reference. This could be done with the polaroid of the output signal - knowing the amplifier gain and doing the same for the input signal, the fundamental frequency could be subtracted. Useless but funny.



In old times people used to have better physical idea or knowledge of what they were talking about.
Nowadays too much un correlation between different departments and cost saving issues may lead to what you describe.
Famous brand digital spectrum analyzers 0-110GHz suffering with unacceptable aliasing issues for example.
Too much software and not enough testing.No magic RF cables for correcting a 100 kEuros test equipment.


----------



## pinnahertz

Leo- said:


> @pinnahertz  actually there may would be a way to get RMSs from old oscilloscopes using your pre-historic method. In the old times before computers were widespread, people would get integral estimates by plotting graphs in heavy paper, carefully cut around the silhouettes and weigh them with a precise scale against a reference. This could be done with the polaroid of the output signal - knowing the amplifier gain and doing the same for the input signal, the fundamental frequency could be subtracted. Useless but funny.


Talk about a ridiculous solution.  The amount of time consumed and lack of precision would disqualify that method on those criteria alone.  There have been distortion analyzers in the world for 70 years for sure, likely longer. Manually tuned and nulled Wien bridge beasts from the 1940s...yes, I've used one of those too...got the answer more quickly and with far greater precision.    

You are technically correct, but practically ridiculous.


----------



## gregorio

Leo- said:


> Well, ok - at least now I understand you're picking up on the semantics not the physics.



Why does this happen? Why is it so common during a discussion/disagreement with audiophiles that they will bring up some irrelevant point, stated as applicable fact or science and then, when someone demonstrates it's clearly wrong, they accuse that person of picking up on semantics rather than the science or applicable facts, of doing exactly what the audiophile himself is actually guilty of?! It's so common that this isn't even the first time it has occurred in this thread; I had a series of exchanges with @Clive101 who quoted a bunch of analogue studio equipment to support his argument and when I explained why the studio equipment he quoted was inapplicable, he accused me of quoting studio equipment in which he had no interest. Again, why does this happen, what's the point of it, how does it benefit the audiophile or his argument? How does accusing others of exactly what they themselves initiated and are guilty of extricate them from the hole they've dug for themselves by making irrelevant and erroneous statements in the first place?

As I explained in post #335 (which you've apparently not read or conveniently ignored), irrespective of your irrelevant and erroneous statements regarding oscilloscopes, your statement ("_It is certainly easy to take measurements, to make meaningful ones it is not so much._") is nonsense at a far more fundamental level: The process of recording and reproducing audio is itself a process of measurement/quantification, so if we cannot take meaningful measurements/quantifications we cannot make meaningful recordings in the first place! Are you saying that audiophile USB cables take un-meaningful audio recordings and turns them into meaningful music? The problem with trying to argue for an audiophile myth is that following the argument through to it's logical conclusion typically results in having to contradict relatively simple, obvious facts and make not just erroneous but utterly ludicrous claims/statements/conclusions. But even this is not the end of the road though, because of course one can always just accuse everyone else of contradicting basic facts and making utterly ludicrous claims! The circular (il)logic world of audiophilia can be fascinating to witness.

G


----------



## Leo-

pinnahertz said:


> Talk about a ridiculous solution.  The amount of time consumed and lack of precision would disqualify that method on those criteria alone.  There have been distortion analyzers in the world for 70 years for sure, likely longer. Manually tuned and nulled Wien bridge beasts from the 1940s...yes, I've used one of those too...got the answer more quickly and with far greater precision.
> 
> You are technically correct, but practically ridiculous.



It does serve an important point which is to show again what a proof by absurd is. We found that there is at least one way (impractical or imprecise it doesn't matter at all) to measure something with the oscilloscope, therefore the assertion "it is impossible to measure thd with an oscilloscope" is false, thereby closing a big parenthesis and supporting my argument that if in at least one situation USB cables do make a difference, then the assertion that all USB cables are the same is false.


----------



## Clive101 (Oct 15, 2017)

gregorio said:


> Why does this happen? Why is it so common during a discussion/disagreement with audiophiles that they will bring up some irrelevant point, stated as applicable fact or science and then, when someone demonstrates it's clearly wrong, they accuse that person of picking up on semantics rather than the science or applicable facts, of doing exactly what the audiophile himself is actually guilty of?! It's so common that this isn't even the first time it has occurred in this thread; I had a series of exchanges with @Clive101 who quoted a bunch of analogue studio equipment to support his argument and when I explained why the studio equipment he quoted was inapplicable, he accused me of quoting studio equipment in which he had no interest. Again, why does this happen, what's the point of it, how does it benefit the audiophile or his argument? How does accusing others of exactly what they themselves initiated and are guilty of extricate them from the hole they've dug for themselves by making irrelevant and erroneous statements in the first place?
> 
> As I explained in post #335 (which you've apparently not read or conveniently ignored), irrespective of your irrelevant and erroneous statements regarding oscilloscopes, your statement ("_It is certainly easy to take measurements, to make meaningful ones it is not so much._") is nonsense at a far more fundamental level: The process of recording and reproducing audio is itself a process of measurement/quantification, so if we cannot take meaningful measurements/quantifications we cannot make meaningful recordings in the first place! Are you saying that audiophile USB cables take un-meaningful audio recordings and turns them into meaningful music? The problem with trying to argue for an audiophile myth is that following the argument through to it's logical conclusion typically results in having to contradict relatively simple, obvious facts and make not just erroneous but utterly ludicrous claims/statements/conclusions. But even this is not the end of the road though, because of course one can always just accuse everyone else of contradicting basic facts and making utterly ludicrous claims! The circular (il)logic world of audiophilia can be fascinating to witness.
> 
> G



Well that's your opinion of which your entitled, I used the example to demonstrate that Torus ( power conditioner ) work for me and for a studio.


----------



## pinnahertz

Leo- said:


> It does serve an important point which is to show again what a proof by absurd is. We found that there is at least one way (impractical or imprecise it doesn't matter at all) to measure something with the oscilloscope, therefore the assertion "it is impossible to measure thd with an oscilloscope" is false, thereby closing a big parenthesis and supporting my argument that if in at least one situation USB cables do make a difference, then the assertion that all USB cables are the same is false.


Wow, someone who is actually more pedantic than I am!


----------



## pinnahertz

Leo- said:


> It does serve an important point which is to show again what a proof by absurd is. We found that there is at least one way (impractical or imprecise it doesn't matter at all) to measure something with the oscilloscope, therefore the assertion "it is impossible to measure thd with an oscilloscope" is false, thereby closing a big parenthesis and supporting my argument that if in at least one situation USB cables do make a difference, then the assertion that all USB cables are the same is false.


The only thing you have actually proven, though, is how you can apply proof by absurd.  That's fine, but it has no bearing on the reality we will encounter reality.  So, at extreme risk of being absurdly logic'd to death...using a scope to "measure" distortion would be an extremely rare case, and actually the misuse of a tool.  It's as ridiculous as saying that because you actually can hammer a nail with a wrench you could build a house without a hammer.  True in the absolute, but ridiculous. 

Perhaps the statement "All USB cables sound the same" is false in the absolute, but it's correct in general and on average in practice.  If you're going to live life in the absolute, they you must die.  Why?  LOGIC!  Everyone who drinks water dies!  And, sooner or later, everyone must drink water.  That means to avoid dying you must stop drinking water, which in turn will  cause your death.   The same principle applies to a far, far greater extent with prescription drugs.  Ever check those side effects?  Many include, in the long list, "death".  If you then applied absolute logic, you'd never take any of them, even if they could actually extend or save your life.  

Wouldn't it be far more beneficial to study the "why" of the anomaly?  If 100 different USB cables were tested in a true ABX/DBT, and with a significant number of tests with a significant number of people we came out with a clear statistical fallout that one cable in 100 did, in fact, present a difference in sound quality where no others did, would it be most relevant to study why that one creates a difference rather than to dogmatically declare, "See!  The statement that "all USB cables sound the same" is FALSE!  One way is research, science and engineering, the other is technically correct, but ridiculous.  If you can discover why the one cable is audible, wouldn't you contribute the the collective knowledge of the science of data transmission?  The other way you contribute to...well, really nothing other than to declare your own rightness. 

Real science recognizes that true absolutes are rare, and many so called absolutes are actually a bit fuzzy.  Engineering embraces that fuzzyness and works with it.   By clinging to the assertion that the statement "all USB cables are the same" is false, you've embraced the world of the barrister, and left the world of science and engineering behind.  You are, as I've said before, both correct and ridiculous.  

How do  we know, for example, that the USB cables that "sound the best" don't degenerate over time?  Is cable rot possible?  Sure it is, I've seen it first hand. In USB cables? No, but in cables in general, yes, old cable with cracked insulation, oxidized conductors, discolored outer jacket, etc.  So then by your logic you should replace your $1000 rotting USB cable periodically because you can't absolutely say they don't rot!  

Can you say, absolutely, that sound itself doesn't cause some physical degeneration?  Hearing loss? Death?  Nope.  So then, stop listening to music!   It's sound, and therefore can cause death.  How about an equipment failure causing electrocution?  You can't even turn you system off without risking that!

Aren't you worried about how many people get struck by lightning?  Or killed by meteors?

Can you say, absolutely, that posting in a forum cannot result in physical degeneration such as RSI as one example? How about some other sickness? Death?  Think carefully now, and take appropriate action.


----------



## bigshot

Leo- said:


> It does serve an important point which is to show again what a proof by absurd is. We found that there is at least one way (impractical or imprecise it doesn't matter at all) to measure something with the oscilloscope, therefore the assertion "it is impossible to measure thd with an oscilloscope" is false.



Congratulations. You've gone from accusing others of semantic arguments to making one yourself, and all in the space of just a couple of posts!


----------



## Leo-

It is funny that I do agree with you in principle, but I admit I'm kinda tired of going around this point in circles. Perhaps we don't have to spend so many bits discussing phylosophy - I'm sure that in person this could render an interesting conversation, but forum discussions somehow tend to reverberate little arguments and turn them into large signal distortions. 

Coming back to where this discussion started, originally I wanted to make a point the few colleagues who stated rather categorically that "USB cables must all sound the same since they only carry bits", and the fact that they don't only do that (electrical noise aside, they also carry power for USB powered DACs), and if different cables are able to isolate the effects of high currents passing through the power cable from the signal ones, then not all cables sound the same in all circumstances if these currents can have a deletereous effect on the signal (timing at the receiver, increased noise, etc). 

And yes, I was almost struck by a lightning once.


----------



## theorist

bigshot said:


> Congratulations. You've gone from accusing others of semantic arguments to making one yourself, and all in the space of just a couple of posts!



All uses of language in a discourse have an effect/affect on the Other, so they are inherently a semantic argument (Lacan 2007).


----------



## bigshot

There's no lack of contentless semantic arguments in internet forums. In fact, lousy debating is the fuel that runs the whole engine.

Unfortunately, I don't have much interest in argumentativeness. I'm more interested in working on improving the sound of music.


----------



## gregorio (Oct 16, 2017)

Clive101 said:


> Well that's your opinion of which your entitled ...



What's my opinion, that you quoted an entire analogue studio as representative of the analogue section of your DAC, that an analogue studio drawing so much power that it trips a 20 amp circuit is not representative of your DAC or that in response to me explaining this, you stated you had no interest in studio equipment and therefore wouldn't respond any further?



Leo- said:


> ... if different cables are able to isolate the effects of high currents passing through the power cable from the signal ones, then not all cables sound the same in all circumstances if these currents can have a deletereous effect on the signal (timing at the receiver, increased noise, etc).



Firstly, that's *IF* a particular audiophile cable does actually provide better isolation and secondly, what "high currents passing through the power cable"? Sure, the studio setup you quoted was drawing a high current but your DAC is not, it's probably drawing no more than a few hundred milli-amps!

No one is saying electrical, source, jitter or other causes of noise does not or should not exist in the analogue section of a DAC. No one is saying a DAC should be able to eliminate all noise, that it should have zero noise and an infinite dynamic range. I'm saying that a DAC can relatively easily and cheaply isolate itself from USB power and other forms of transmitted noise well enough to reduce that noise to levels well below audibility. This is not an opinion, it's a fact and it's a fact not only because science and electrical engineering indicates it should be the case, it's a fact because there are cheap DACs on the market which actually demonstrate it! If cheap DACs can achieve this feat, why can't more expensive or very much more expensive audiophile DACs? Which brings us back to the two options of why we might hear a difference between ordinary and audiophile USB cables:
1. There is no actual difference, the difference heard is not in the actual sound output by the DAC but in the perception/imagination of the listener OR
2. That the DAC is incompetently designed, flawed or broken.

There is a third potential option, the case of an extreme environment but exceedingly few consumers, if any at all, will routinely encounter such circumstances. In the vast majority of cases I assume the first option to be the explanation but that IS an opinion because I have not measured or seen reliable measurements for the vast majority of audiophile DACs.

G


----------



## pinnahertz

Leo- said:


> Coming back to where this discussion started, originally I wanted to make a point the few colleagues who stated rather categorically that "USB cables must all sound the same since they only carry bits", and the fact that they don't only do that (electrical noise aside, they also carry power for USB powered DACs), and if different cables are able to isolate the effects of high currents passing through the power cable from the signal ones, then not all cables sound the same in all circumstances if these currents can have a deletereous effect on the signal (timing at the receiver, increased noise, etc).


USB 1.0 and 2.0 cables are made of 4 unshielded wires.  The 4 wires are: GND, +5, and two data wires operated as a *differential pair.*  USB 3.0 adds two additional *differential pairs *(internally individually shielded or using twin-ax cable).  The point of the differential data pairs is noise immunity.  The device that receives the data looks for a difference between each wire of the pair and ignores any signal that is common. A noise signal from an external source that is coupled to the wires, either inductively, capacitively, or electromagnetically arrives on all wires equally, making that noise signal common mode, and easily rejected by the use of differential data signals.  Noise that may be on the Gnd or +5 wires that may couple to the data pairs is also coupled equally to all wires, also making that signal common mode, and easily rejected.  When an overall shield is added to some cables (not part of the USB 1 or 2 spec), and grounded, it provides electrostatic and electromagnetic shielding against external signals, reducing coupling, except for the inductive component for which the shield is useless.  However, should an external noise signal be inductively coupled, or manage to penetrate the shield since no shield is perfect, the coupling would still be common mode to the data pairs.  USB 3/Superspeed cables have by specification their data pairs internally shielded to maximize noise immunity and minimize data crosstalk.

When a differential pair is used and applied to a differential receiver, the common mode rejection ratio should be at least 50dB, but 70dB is not atypical. Assuming worst case of 50dB, that means that if you could (and you can't!) induce a noise voltage into a USB cable equal in amplitude to the 5V peak data signal, common mode rejection would see it as a .016V noise signal. However, considering the actual strength of an external noise source and coupling losses, induced noise voltages are far, far below that.  The integrity of the data is ensured by the differential pair technique. 

The single biggest problem with USB of all flavors is that a ground is carried end to end, which presents the strong possibility of a ground loop if the devices being connected have a difference in ground potential.  That difference in ground potential is a problem, a design flaw, that can be remedied in other ways. But because when USB cables include an overall shield, and that shield is grounded at both ends, the resistance of the device to device ground connection is reduced, and both devices are brought closer to the same ground potential.  This may in some circumstances reduce ground loop noise.  But it doesn't affect the data because it's already immune, being differential.  Again, ground loop noise is the result of a device design flaw, or a flaw in installation, it's not supposed to be there in the first place, and could be remedied without the use of a special USB cable. 

The USB interface was designed to transmit data between devices without corrupting the data.  That's why differential data pairs are used.  The chance that actual data corruption is occurring because of coupled noise is extremely unlikely. 

When audiophiles "listen to USB cables", and hear things they describe as more "open", or "better detail", these are not qualities that can be achieved by altering the data path.  Problems in the data path only result in corruption of data, which only can result in increased noise.  Any of the changes described by illustrative or analogous terminology could only occur if data were altered via some form of DSP that could affect a change without corruption.

One last thing, the capability to provide bus power over USB has a number of well defined specifications and different levels of power/current.  However, the thing to note here is that devices must tolerate a 5% voltage fluctuation, and in the case of USB 3, operate down to 4V.  That implies power conditioning and regulation at the device, making that device immune to noise on the power wire.  This doesn''t eliminate the ground loop problem, but does reduce the possibility that noise induced into the 5V line would inject itself into the device that way.


----------



## Arpiben (Oct 16, 2017)

pinnahertz said:


> .......... When an overall shield is added to some cables (*not part of the USB 1 or 2 spec*).....



Just a detail but USB 2.0 specifies outer shield and a drain wire for H.S/F.S cables. When dealing with L.S it is only recommended. (cf abstract hereunder)
Micro USB cables are sharing the same mechanical specs with the exception of Quad Type Micro-USB ( power&data pairs twisted) where no drain wire is allowed.
Let's note that Micro-USB cables are limited to 2 meters length (10ns latency).


*Abstract USB 2.0  Specification*

*High-/full-speed cable* consists of one 28 to 20 AWG non-twisted power pair and one 28 AWG twisted data

pair with an aluminum metallized polyester inner shield, 28 AWG stranded tinned copper drain wire,
> 65% tinned copper wire interwoven (braided) outer shield, and PVC outer jacket.

*Low-speed cable* consists of one 28 to 20 AWG non-twisted power pair and one 28 AWG data pair (a twist
is recommended) with an aluminum metallized polyester inner shield, 28 AWG stranded tinned copper
drain wire and PVC outer jacket. A > 65% tinned copper wire interwoven (braided) outer shield is
recommended.

Edited: electrical specs replaced by mechanical specs + added picture


----------



## pinnahertz

Arpiben said:


> Just a detail but USB 2.0 specifies outer shield and a drain wire for H.S/F.S cables. When dealing with L.S it is only recommended. (cf abstract hereunder)
> Micro USB cables are sharing the same mechanical specs with the exception of Quad Type Micro-USB ( power&data pairs twisted) where no drain wire is allowed.
> Let's note that Micro-USB cables are limited to 2 meters length (10ns latency).
> 
> ...


Good catch, so USB differential data pair is always shielded, and the outer shield is at least recommended, and specified for high speed cables.  

Now somebody detail how any of this can be "improved" upon by exotic cables to the extend that there's less data corruption caused by noise signal coupling.


----------



## Niouke

they even specify the materials to use, that leaves litle room for improvement, except if you want to put gold anywhere you can


----------



## pinnahertz

Niouke said:


> they even specify the materials to use, that leaves litle room for improvement, except if you want to put gold anywhere you can


You don't have to look very long to find exotic cable manufacturers extolling the "benefits" of their use of special materials and metals. Of course there are no specifications or test results...because there can't be.


----------



## Leo-

Exotic materials won't do anything for USB, sorry to disappoint you. A nominal impedance of 90 Ohms is needed between the transmitter and the receiver, so departing from the nominal can only degrade things. I'll quote John Svenson's tech corner which sheds some light in what should influence the signal transmission (note: SI - signal integrity, PHY - physical layer):

"
_Remember that SI consists of rise/fall time, noise, and jitter. The jitter in the SIGNAL is determined by the transmitter PHY, which can be significantly influenced by the clock IT gets and the noise on its PG planes. USUALLY noise is low on the signal as it exits the PHY. The cable (and connectors) cause an increase in raise/fall times, added noise (EMI and crosstalk from power and ground wires) and decreased amplitude of the signal. Any decent receiver will have an automatic gain control (AGC) which compensates for this effect, but that raises the noise on the signal, so I'm lumping the amplitude decrease into noise. The cable by itself rarely adds jitter to the signal, BUT the increased rise/fall times and extra noise cause the received data to have increased jitter in the PHY. This is one of the big issues that all that extra processing is designed to deal with._
"
full link here 

His words are in agreement with USB spec. The specification is rather loose in terms of transmit rise/fall times (max. 25% of mismatch), however it clearly states the following:

_To get better system performance try to match termination impedance as close as possible_

So aside from the connectors, what else affects the signal quality? Cable resistance reduces signal strength and so S/N ratio, so keep cables as short as possible. What affects rise/fall times? One thing would be if noise rejection is not really negligible (I'm speculating here). Just to be on the safe side, one can simple disconnect the +5V line if not needed. Matching the 90 Ohms impedance as per the spec. What else?

Those details seem far from exotic to me, however I wouldn't be surprised if the bulk of cables sold out there are outside the nominal parameters. At least with Ethernet, the percentage of cables outside specs is surprisingly high - and very few manufacturers actually test them before shipping.


----------



## bigshot

You shouldn't have to test a cable before shipping it. If it's properly designed and manufactured, it's going to work properly... and it isn't rocket science to design and manufacture a USB cable. I can see how errors might occur in theory, but I don't see errors as being at all likely in practice. If the Chinese can't make a USB cable that functions properly, how are they possibly going to be able to make a 50 inch flatscreen TVs that works properly?


----------



## ev13wt (Oct 16, 2017)

The philosopher said it best.

Sound reproduction is an illusion.

Have fun with you percentages of sound differences, but please leave bull like "digital cable sound" out of this subforum.

The people who invented it (edit: USB) are laughing at you.

How can a person be so delusioned? You come to a science forum and seriously claim to be able to "help"?

Wow.


I am amazed at the stupidity of people daily, why do I even bother responding?

Its worth it.


----------



## Harry Manback

ev13wt said:


> The philosopher said it best.
> 
> Sound reproduction is an illusion.
> 
> ...



You say digital signal cables, as if there is a difference between analog electrons and digital electrons.  "Digital" is the way that the signal transmitted through the cable is interpreted.


----------



## castleofargh

ev13wt said:


> The philosopher said it best.
> 
> Sound reproduction is an illusion.
> 
> ...


well this topic was only recently moved in this section, so please be a tiny bit more accepting of people who got dragged here unwillingly. if the same thing happened in reverse I would feel so trapped.


----------



## theorist (Oct 16, 2017)

The name of this thread is: Why do USB cables make such a difference?

I was under the understanding that this was the 'DBT free part of the forum', at least according to the Moderator:



Brooko said:


> this is the DBT free part of the forum.  .



Yet now this appears to be moved to the  science DBT subforum section. We all have are entitled to our believes, but mine certainly are not belonging here where positivism reigns as the only possible one correct and absolute truth.



ev13wt said:


> please leave bull**** like "digital cable sound" out of this subforum.
> 
> The people who invented it are laughing at you.
> 
> ...



If someone has hijacked this thread and moved it, can it be pleased put it back where it belongs, so we don't have to put up with dogmatically offensive and derogatory comments of this kind.


----------



## bigshot (Oct 16, 2017)

WELCOME TO SOUND SCIENCE! Sorry about your preconceived biases!

I think they periodically move really dumb threads into sound science just to entertain us. We're actually a lot of fun if you get to know us.


----------



## theorist

bigshot said:


> WELCOME TO SOUND SCIENCE! Sorry about your preconceived biases!
> 
> I think they periodically move really dumb threads into sound science just to entertain us. We're actually a lot of fun if you get to know us.



No thanks, I think I would rather go to dinner at the White House, at least the conversation there would be more intellectually stimulating.


----------



## bigshot (Oct 16, 2017)

Well then, I'll present you your check and you can pay at the door. Thanks for playing! We have some lovely parting gifts for you...

Oh! One last thing... I really like the photo of the vole you use as your avatar!


----------



## theorist

bigshot said:


> We have some lovely parting gifts for you...



What a free bit-perfect USB cable?


----------



## bigshot

MADE OF THE FINEST UNOBTANIUM!


----------



## theorist

bigshot said:


> MADE OF THE FINEST UNOBTANIUM!



What, shipped all the way from Pandora?


----------



## bigshot

Shipped all the way from the land of magical thinking where there's no science-- just phoolosophy!


----------



## theorist

Its not magical thinking, its simply the better music created by the audiophile ethernet connections to the Tree of Souls. Which, by the way, is made out of unobtainium.

PS I see how you can easily run up 15k+ posts in 13 years!


----------



## bigshot

I usually find that better musicians make better music. Wires usually have nothing to do with that.

Well.... are you leaving now?


----------



## theorist

bigshot said:


> Well.... are you leaving now?



Only when the discussion thread goes back to the sub-forum area where it correctly belongs, but you as everyone else are most welcome to come along, because discussion on this threat does not foreclose diverse beliefs and perspectives. Also, you have also demonstrated a sense of humour, as well as a love of beautiful little voles (we call it a dog in my part of the world).


----------



## Brooko

theorist said:


> The name of this thread is: Why do USB cables make such a difference?
> 
> I was under the understanding that this was the 'DBT free part of the forum', at least according to the Moderator:
> Yet now this appears to be moved to the  science DBT subforum section. We all have are entitled to our believes, but mine certainly are not belonging here where positivism reigns as the only possible one correct and absolute truth.
> If someone has hijacked this thread and moved it, can it be pleased put it back where it belongs, so we don't have to put up with dogmatically offensive and derogatory comments of this kind.



Not my call - was done by one of the Admins (personally I would have left it where it was - I thought some of the insights gained there were quite good).  You can PM axelcloris if you feel it should be moved back (I think it may have been his call to move it).

And FWIW I do think it would be far more constructive for some SS members to take the same approach as Gregorio, and try to work explaining things rather than ridiculing.  But ultimately you guys will need to work that out.


----------



## bigshot

If it gets moved back, give them all my love!


----------



## bigshot

Brooko said:


> FWIW I do think it would be far more constructive for some SS members to take the same approach as Gregorio, and try to work explaining things rather than ridiculing.



You haven't seen Gregorio when he gets on a roll!

All of us are happy to explain and share. The problem is that if someone is dug in deep with audiophoolery, they don't want to learn. They just want validation. And when we don't give them the validation they want, they get mean... That's my cue to stop trying to explain and turn to just trying to have fun with their pompousness.


----------



## theorist

bigshot said:


> All of us are happy to explain and share. The problem is that if someone is dug in deep with audiophoolery, they don't want to learn.



Not necessarily, Gregorio and others, suggested that I double blind test USB cables which I did, even following (until it became too tedious) his detailed protocol. See: 


theorist said:


> *post #205.*



Guess what? Right from the start of the DBT I could readily and repeatedly hear and identify the difference between the three USB cables that I and my cable swapper tested. Interestingly, the generic cable and the rather expensive one had less immediate difference than the intermediate priced cable, although my overall preference correlated with the price order.

Yes, I have seen all the explanation as to why this _must_ be 'impossible', and courtesy of Gregorio and others I now understand much of the theory pertaining to this position starting from Shannon (1948) onwards, but these differences in USB cables are still perceptually there somehow. Hence my interest to understand why in this thread. I would be interested in your contribution to my understanding, not to mention humour and cool picture(s), but really don't find ev13wt's post, even though not directly aimed at me, helpful or constructive, as there is no need for that kind of negativity.


----------



## castleofargh

theorist said:


> No thanks, I think I would rather go to dinner at the White House, at least the conversation there would be more intellectually stimulating.


maybe you can show your dissatisfaction without having to insult everybody here. you know this forum has rules right?  I should delete this post but then I should probably remove about 15 of the latest posts. me being pro free speech really has a heavy cost on the SNR of a topic. 
until now you've been more reasonable than most of the proponents of expensive cables, please keep doing so. or indeed leave, the forum is big enough. I did just that by unsubscribing before the topic was dumped in here, and my life was very fine.


----------



## bigshot (Oct 17, 2017)

theorist said:


> Guess what? Right from the start of the DBT I could readily and repeatedly hear and identify the difference between the three USB cables that I and my cable swapper tested.



How about introducing us to your "cable swapper" we would love to meet him!


----------



## pinnahertz

theorist said:


> Not necessarily, Gregorio and others, suggested that I double blind test USB cables which I did, even following (until it became too tedious) his detailed protocol. See:
> 
> Guess what? Right from the start of the DBT I could readily and repeatedly hear and identify the difference between the three USB cables that I and my cable swapper tested. Interestingly, the generic cable and the rather expensive one had less immediate difference than the intermediate priced cable, although my overall preference correlated with the price order.
> 
> Yes, I have seen all the explanation as to why this _must_ be 'impossible', and courtesy of Gregorio and others I now understand much of the theory pertaining to this position starting from Shannon (1948) onwards, but these differences in USB cables are still perceptually there somehow. Hence my interest to understand why in this thread. I would be interested in your contribution to my understanding, not to mention humour and cool picture(s), but really don't find ev13wt's post, even though not directly aimed at me, helpful or constructive, as there is no need for that kind of negativity.


I read through all of that the first time you linked to it and decided to withhold comment, but since you brought it up again...

Your test was certainly NOT a DBT, and absolutely did not follow the ABX protocol.  There were uncontrolled biases, an nowhere near enough data was collected to draw a valid statistical conclusion, yet conclusions were drawn, and firmly presented as if they were conclusive.  They were anything but.


----------



## bigshot

Pin, can I post the sad trombone again?


----------



## pinnahertz

bigshot said:


> Pin, can I post the sad trombone again?


By all means, knock thyself out.


----------



## Clive101

gregorio said:


> What's my opinion, that you quoted an entire analogue studio as representative of the analogue section of your DAC, that an analogue studio drawing so much power that it trips a 20 amp circuit is not representative of your DAC or that in response to me explaining this, you stated you had no interest in studio equipment and therefore wouldn't respond any further?



No, I had noise and I treated for it in the same way that's all.


----------



## Clive101 (Oct 17, 2017)

Thought I may a post link which some may find of interest.

https://www.head-fi.org/threads/watts-up.800264/page-24#post-13787487 post #356.

Happy reading.


----------



## ev13wt

theorist said:


> Not necessarily, Gregorio and others, suggested that I double blind test USB cables which I did, even following (until it became too tedious) his detailed protocol. See:
> 
> 
> Guess what? Right from the start of the DBT I could readily and repeatedly hear and identify the difference between the three USB cables that I and my cable swapper tested. Interestingly, the generic cable and the rather expensive one had less immediate difference than the intermediate priced cable, although my overall preference correlated with the price order.
> ...



The negativity is simply because currently "you" are in the science forum, and crap like this doesn't fly here. 

*I apologize if I stepped on anyones toes.* But if you hear differences between USB cables, then its either a broken or not built correctly cable, broken or not built correctly equipment - or its your head. There is no room for debate here. Not in a science forum, you know SCIENCE - the people who invented the audio and digital and USB you are trying to hobbanalyze...

Simply no. 




*Bu the s304 cagain, ma be I am simply u2ing the wrong e4hernet cabl4 again... damn! I am. Whew, that was close - now it works better.*


----------



## ev13wt (Oct 17, 2017)

Clive101 said:


> Thought I may a post link which some may find of interest.
> 
> https://www.head-fi.org/threads/watts-up.800264/page-24#post-13787487 post #356.
> 
> Happy reading.




I would accept his marketing slideshow if there are samples to download. But alas, there is nothing but words.  Nice words too. First he established credibility, then he talk with big words, coming to an obvious conclusion, pimping / selling his noise shaping math and solving main and interconnect sound differences with a single shot!





Harry Manback said:


> You say digital signal cables, as if there is a difference between analog electrons and digital electrons.  "Digital" is the way that the signal transmitted through the cable is interpreted.



You are very correct. I used an over-simplification. Not good.

And this is in essence why digital transmission will either work or not. Either the other side can see a peak as a "1" or not. How the peak looks like is almost secondary.


----------



## Brooko

ev13wt said:


> The negativity is simply because currently "you" are in the science forum, and crap like this doesn't fly here.
> 
> *I apologize if I stepped on anyones toes.* But if you hear differences between USB cables, then its either a broken or not built correctly cable, broken or not built correctly equipment - or its your head. There is no room for debate here. Not in a science forum, you know SCIENCE - the people who invented the audio and digital and USB you are trying to hobbanalyze...
> 
> ...



And what you are missing is the fact that the thread was moved from the cable DBT free forum by an admin - where the actual debate was quite civil and respectful.  It comes in here (not by theorist's choice either), and you get on your hobby horse, and immediately attack the guy.  And what happened to trying to see the other persons point of view, find out where he may have gone wrong, and teach rather than ridicule.

Honestly - putting things in large text and mispelling like that is a child's approach.  If that is all you have, then why did you even bother replying?

For the record - I don't know why the thread was moved - but it was done by an Admin, and they trump a mere Moderator.


----------



## ev13wt (Oct 17, 2017)

Brooko said:


> And what you are missing is the fact that the thread was moved from the cable DBT free forum by an admin - where the actual debate was quite civil and respectful.  It comes in here (not by theorist's choice either), and you get on your hobby horse, and immediately attack the guy.  And what happened to trying to see the other persons point of view, find out where he may have gone wrong, and teach rather than ridicule.
> 
> Honestly - putting things in large text and mispelling like that is a child's approach.  If that is all you have, then why did you even bother replying?
> 
> For the record - I don't know why the thread was moved - but it was done by an Admin, and they trump a mere Moderator.




I saw it was moved.
I thought about what I will post.
Big text for big heads / egos / missing education

I am not attacking anyone, but sometimes it makes sense to "explain" a subject in the language and style of the person that "aren't getting it".
Explaining did not work.
Explaining it again did not work.
Explaining it in technical detail did not work.

Its time to smack words into heads.

I think I am not very good at social skills and "fine lines".
I speak how it is. In. Very. Simple. Words.



USB "cable sound differences" is like building square tires and proclaiming that "it works" and "rides better".


----------



## ev13wt

Think about it. Someone invents a pretty complicated gizmo.
Shows it to the worlds.
People who seriously have no clue how it works start threads about how they "pimped" the unit to make it work better.
Again, they do not know how it works.
The maker comes in and tells them that it doesn't work and they are imagining things.
The thread goes 100 pages.

Fuel magnets.
Oil changes making the car faster / better / more efficient
Cold air intakes that kill bottom end "are moar fasterer"
Huge exhausts that build back pressure or don't deliver enough - more HP. Always.



The irony is, that we are using digital transmission in this forum. All the letters are correct. How can this be? It IS. As such, digital transmission is "perfect" if it works, the end. I don't even understand how these threads go so crazy.


----------



## ev13wt

This sums it up for all things audio. And more.

The smaller the difference, the more it is discussed and seemingly relevant. Why?


----------



## Brooko (Oct 17, 2017)

I'll put it in an easy sentence for you to understand then.

Person has preconceived ideas, but expresses willingness to at least listen, and genuinely makes an attempt to run tests.  First person (gregorio) takes the time to explain the science, and work through the why and to counter the preconceived ideas, and give answers that refute the fallacies and at the same time informs.  its a slow process - but worth the investment in time, because the message is slowly being taken in.

Second person comes along (you), clearly doesn't want to help and simply wants to show their own superiority (in their own mind).  Instead of a conversation you get a lecture.

if you don't want to help, then why do you bother even engaging?

Its exactly this sort of attitude that currently has me looking to other forums at the moment.  Head-Fi used to be better than this.


----------



## gregorio

theorist said:


> Not necessarily, Gregorio and others, suggested that I double blind test USB cables which I did, even following (until it became too tedious) his detailed protocol.



As well as boldly heading your post #205 "*USB Cable Double-blind Shoot Out.*", you continue to refer to it as a double-blind test, despite the fact it's obviously a single-blind test. How is it even remotely possible that as a (self proclaimed) uni professor in the philosophy of science you apparently do not know the difference between single and double blind testing? How is it possible even for an under-grad, let alone a professor?



theorist said:


> I was under the understanding that this was the 'DBT free part of the forum'



Really? Then why did you conduct and post your conclusions of a test which you boldly described as DBT while this thread was in the DBT free part of the forum?



theorist said:


> Yes, I have seen all the explanation as to why this _must_ be 'impossible', and courtesy of Gregorio and others I now understand much of the theory pertaining to this position starting from Shannon (1948) onwards, but these differences in USB cables are still perceptually there somehow. Hence my interest to understand why in this thread.



We've spent a considerable portion of this thread discussing grounding and other potential electrical, EM/RF isolation issues which could cause noise in a poorly designed DAC. However, even if it were the case that you and others are using seriously flawed/faulty DACs, resulting in audible noise, this would still NOT explain what you and others are describing. You (plural) are not just saying you can detect a difference, you are stating that you can consistently detect specific differences. Specific differences not in the amount of noise/the noise floor but differences such as improved separation, improved soundstage, improved bass extension, heft or palpability and/or improvements in other frequency bands. These specific differences require differences to the digital data bits themselves and, not just changes to random bits but to very specific bits AND to the exact same very specific bits every time you play the recording! This is plainly ridiculous unless you claim that a USB cable contains digital signal processing software + processing power to execute it or some sort of magic which achieves the same result. However, you've already accepted that USB cables do not change the bits, so, *what are you left with*? ... Even if you believe that human perception/bias is a highly improbable explanation (which it is not), it would still rationally/logically HAVE to be the correct explanation as every other explanation is impossible!

G


----------



## ev13wt (Oct 17, 2017)

Brooko said:


> I'll put it in an easy sentence for you to understand then.
> 
> Person has preconceived ideas, but expresses willingness to at least listen, and genuinely makes an attempt to run tests.  First person (gregorio) takes the time to explain the science, and work through the why and to counter the preconceived ideas, and give answers that refute the fallacies and at the same time informs.  its a slow process - but worth the investment in time, because the message is slowly being taken in.
> 
> ...




You see, I have done the explaining and the hand holding. I have built DBTs for members to participate in even. At a certain point the love is enough, and reality must be shown for what it is. Some people don't like it, but hey. They might thank me later.

It has zero to do with my "superiority" about anything.


Other forums? Here we can at least debate and discuss anything. In any context.I know what forum you should look at:

Hydrogenaudio: All DBT, you post about non proveable sound differences you will be reminded once and then you get banned the end.

Most audiophile boards: Say anything along the lines of "can't be" or "prove it with a DBT" and, well, you simply get banned without a warning. Its a reach around fest of "listen to my expensive USB cable BS"


I love this forum. It HAS turned into a snake oil, high end, cable sound board over in General Headphones, with each new product being hyped to the heavens. But maybe it will balance itself out. But then again, we don't have 20K power cables yet.

I predict the end is 20K headphones that people MUST HAVE to get the best sound.
Where is it now? 2000 USD for great high end sound? More?

What about a Beyer 880? Are headphones costing 8 times as much really 8x better? 2x better? Nope. 5% different. Do I want a Layla or Stax or Fostex or Hifiman? Well hell yea!!!! (Not hifiman, cannot stand the name)


----------



## Brooko (Oct 17, 2017)

You didn't answer my point - you don't even see it.  You didn't need to engage at all - its just a "superiority trip" for you.  And why the sudden off-topic crap?  It has nothing to do with the topic at hand

Are you this way when you're not behind a keyboard?

I'm out of here.


----------



## ev13wt

gregorio said:


> However, you've already accepted that USB cables do not change the bits, so, *what are you left with*? ...
> G



Some people cannot help themselves. They see the idea, even believe it, but will NEVER publicly change their mind for the fear of being seen as "wishy washy" or "without a standpoint". 

In essence, this is why in real life, people are sorted out into groups. You know - blue collar tradesman, scientists, certain education level. Its why we have degrees and such. All they say is: "This person can analize ideas and write about them and combine them and come to conclusions" a bit of "can talk about this stuff on a level where all other relevant parties will understand - and all can work together".

Disclaimer: I do not put any weight into any profession being "better" than another. Trades are probably worth more in my book!  But stick a audio engineer ultra geek and a street smart bricklayer into a room and try discussing ... anything.

In forums we do not have this. We don't even know the AGE of the other person. This information alone could really help.


----------



## ev13wt (Oct 17, 2017)

Brooko said:


> You didn't answer my point - you don't even see it.  You didn't need to engage at all - its just a "superiority trip" for you.  And why the sudden off-topic crap?  It has nothing to do with the topic at hand
> 
> Are you this way when you're not behind a keyboard?
> 
> I'm out of here.




I am this way in real life too. We really should have a beer. Off topic can sometimes be helpful.

Here is another off topic for you, I hope you enjoy it. https://xkcd.com/1901/






Do you get what I am doing yet?



edit: I can't get over the "superiority complex" accusation. Really. I am saying: "The sun comes up in the morning". You can argue all you want from the inside of a cave. The sun comes up. Nothing superior about this information.

Sometimes you need to physically drag a person FROM the cave. Hard with words and some people..


----------



## Triode User (Oct 17, 2017)

Yeah, OK that's all fun and we appreciate the sniggers and fun that you are having but no one is actually saying that the digital transmission is not perfect.
After all, we get music out of the other end with no clicks or other noise so we agree the digital signal must be fine and unaltered.
But when a designer of a well respected DAC (Rob Watts, designer of the Dave DAC) regularly discusses the impact that RF noise in a digital cable can have on the sound of the DAC, it is at that point that I do not think it is particularly helpful to met by yet more sniggers on here and for people to say that either his design or his DAC must be broken.
The condescending and mocking tone of posts by the guardians of science on here regarding Rob Watts' description of his designs is also unhelpful and does not show those posters in a good light.


----------



## castleofargh

a radicalized point of view is always at least partially false and they exist on both sides. sadly I'm often one of them.  I blame it all on how forum members are still mostly made of people in 2017, and how the sound science section is open to non Nobel prize winners. 
IMO this topic ended the moment if was moved here. it's obviously pissing off both sides of the argument and will only achieve to get someone banned.


----------



## JaeYoon

But you gotta give it to headfi to allow people to spread their ideas.

On hydrogenaudio people will be gone without any test logs/DBT done.

Oh you hear RF affecting your cables. We eagerly await your test logs or you will have breached the TOS when you signed up.


----------



## bigshot

Brooko said:


> And what you are missing is the fact that the thread was moved from the cable DBT free forum by an admin



I think there was a reason for it. Someone was probably getting tired of something or someone in the thread and wanted to teach them a lesson. I think the folks from the cable forum should take a moment and try and figure out what that was. All of us here in Sound Science are just doing what we do in Sound Science. We're nice and stay inside our box. We don't venture out. That isn't true of non-science people. We get a steady stream of logical fallacies and magical thinking coming into this group. We give every opinion the respect it deserves.


----------



## Triode User

castleofargh said:


> a radicalized point of view is always at least partially false and they exist on both sides. sadly I'm often one of them.  I blame it all on how forum members are still mostly made of people in 2017, and how the sound science section is open to non Nobel prize winners.
> IMO this topic ended the moment if was moved here. it's obviously pissing off both sides of the argument and will only achieve to get someone banned.



Agreed. It would have been better to close the thread rather than move it. Personally I’m out of this thread now as I will eventually get pissed off enough to say something and get banned and I rather like the discourse in other threads so that would be cutting my nose off to spite my face. 

See ya.


----------



## theorist

pinnahertz said:


> I read through all of that the first time you linked to it and decided to withhold comment, but since you brought it up again...
> 
> Your test was certainly NOT a DBT, and absolutely did not follow the ABX protocol.  There were uncontrolled biases, an nowhere near enough data was collected to draw a valid statistical conclusion, yet conclusions were drawn, and firmly presented as if they were conclusive.  They were anything but.



Agree it was not a DBT or follow the ABX protocol, but I did not wish to rub the Science Forum supporters noses the wrong way who were contributing to the thread (before it was re-located) by pointing this out, when they suggested the methodology, or at least did not raise this as an issue within it. Of course, it would only be double-blind if the cable swapping itself was appropriately 'black boxed', and this is far from easy to do in a home environment especially with different in physical appearance cables. However, the test was sufficient to convince me that there was a repeatable material difference in the reconstituted sound correlated with each particular cable, not one solely constructed by my expectation or other mentally induced biases. 

Further, with 100% correlation there is statistical validity even when the N is quite small.

Now I'm done and will let you get on with your 'science'.


----------



## bigshot (Oct 17, 2017)

Sighted tests don't do anything to prevent bias from creeping in. And the first thing we suspect when someone says some cables sound better than others is bias. The only thing you confirmed was your bias. You still haven't proved that the cables actually do sound different. That's really easy to test for, but you have to actually want to know the answer, even if it doesn't match your bias.


----------



## JaeYoon

bigshot said:


> Sighted tests don't do anything to prevent bias from creeping in. And the first thing we suspect when someone says some cables sound better than others is bias. The only thing you confirmed was your bias. You still haven't proved that the cables actually do sound different. That's really easy to test for, but you have to actually want to know the answer, even if it doesn't match your bias.


This why DBT are hard to do. Someone has to want to do it.

Say for instance you really like this cable. You compare it to a bland regular cable off amazon basics. Already the owner will have this preference for their favorite cable to win.

Someone like rollswindowsdownmanually used an abx switcher to compare amps and headphones with the help of his wife to hide the amps from view or so.

So he couldn't see which product was which.

It's understandable many people choose not to use this method. If you like a piece of equipment. You don't want to see it being compared to other products and either being same or losing.

It can part of human psyche in general depending on person.

I'm not against people who believe in cable differences here. Just open to people sharing their views too.


----------



## gregorio

Triode User said:


> But when a designer of a well respected DAC (Rob Watts, designer of the Dave DAC) regularly discusses the impact that RF noise in a digital cable can have on the sound of the DAC, it is at that point that I do not think it is particularly helpful to met by yet more sniggers on here and for people to say that either his design or his DAC must be broken. The condescending and mocking tone of posts by the guardians of science on here regarding Rob Watts' description of his designs is also unhelpful and does not show those posters in a good light.



Right there we have a large part of the problem, a part which I've mentioned numerous times but which is consistently ignored, the BS marketing pervasive in the audiophile world and the reason it's employed, to create biases which hopefully will affect audiophile's perception. You've obviously have substantial respect for Rob Watts but based on his posts (this one quoted previously, for example), I have no respect for him at all, in fact quite the opposite! All it takes to realise this, as I've said before, is a few basic facts and the application of a little logic. I could go through his post point by point demonstrating it to be nonsense but let's just take the main point, that of noise/distortion down to -200dB (and beyond) being audible. The basic fact to know is that if 0dB is equivalent to the sound level of a truck driving past a few meters away, then the approx -144dB limit of 24bit would be roughly equivalent to the to the sound level of two hydrogen atoms colliding! This should raise a couple of questions:

1. Assuming you realise that a sound wave is a pressure wave which travels through air, how would the tiny pressure produced by two hydrogen atoms colliding be enough to move the billions of air molecules necessary to propagate a sound wave in the first place? - Answer - It couldn't, there is no way that could be achieved. In theory, the noise created by just the sub-atomic particles (electrons) colliding inside resistors and other electrical components in a DAC limits the lowest noise floor achievable to about -132dB but in practise no one has achieved this. The lowest noise floor of any DAC on the market that I'm aware of is about -124dB, roughly 10 times higher than the theoretical limit of 24bit. In practise we don't have to be even slightly concerned about this, as your speakers or headphones have a much higher noise floor and there are no commercial recordings I'm aware of with a noise floor lower than -60dB, which is 100-1,000 times higher than even relatively cheap DACs!
2. Watts is going on about noise/distortion far lower than the sound of two hydrogen atoms colliding though, 1,000 - 100,000 times lower! What in the real world could even create such a ridiculously low sound pressure level? Maybe a quark scratching it's nose? You think it's even possible that a sound pressure wave at that level could be propagated, that your speakers/headphones have anywhere even vaguely near that resolution or that the billions of molecules which make up your eardrum could be in any way affected by it? 

Out of curiosity, what is the claimed signal to noise ratio of a Chord Dave? That alone is enough to demonstrate Watts is talking utter, laughable nonsense, provided of course you know what "signal to noise ratio" means! And you wonder why we're using a condescending and mocking tone?

G


----------



## bigshot

That logical fallacy is called "Appeal to Authority".


----------



## JaeYoon

bigshot said:


> That logical fallacy is called "Appeal to Authority".



Just imagine if Jim Jones was in control of a massive amount of audiophiles. Told them to drink the kool aid and it will bring them to audio nirvana.

In fact that kool aid would make cables sound every audiophiles dream. Just imagine a 3D soundstage where you are suspended in midair with all the notes flying around you.

In fact imagine drinking this kool aid and you wouldn't hear any jitter or EMI or anything that could possibly affect your audio listening experience.

Now sit down, plug in those expensive cables, get a nice jug of audio nirvana kool aid. Drink it down real deep!

Bigshot how many audiophiles do you think would drink it down if Rob watts told them to.


----------



## Arpiben

gregorio said:


> Right there we have a large part of the problem, a part which I've mentioned numerous times but which is consistently ignored, the BS marketing pervasive in the audiophile world and the reason it's employed, to create biases which hopefully will affect audiophile's perception. You've obviously have substantial respect for Rob Watts but based on his posts (this one quoted previously, for example), I have no respect for him at all, in fact quite the opposite! All it takes to realise this, as I've said before, is a few basic facts and the application of a little logic. I could go through his post point by point demonstrating it to be nonsense but let's just take the main point, that of noise/distortion down to -200dB (and beyond) being audible. The basic fact to know is that if 0dB is equivalent to the sound level of a truck driving past a few meters away, then the approx -144dB limit of 24bit would be roughly equivalent to the to the sound level of two hydrogen atoms colliding! This should raise a couple of questions:
> 
> 1. Assuming you realise that a sound wave is a pressure wave which travels through air, how would the tiny pressure produced by two hydrogen atoms colliding be enough to move the billions of air molecules necessary to propagate a sound wave in the first place? - Answer - It couldn't, there is no way that could be achieved. In theory, the noise created by just the sub-atomic particles (electrons) colliding inside resistors and other electrical components in a DAC limits the lowest noise floor achievable to about -132dB but in practise no one has achieved this. The lowest noise floor of any DAC on the market that I'm aware of is about -124dB, roughly 10 times higher than the theoretical limit of 24bit. In practise we don't have to be even slightly concerned about this, as your speakers or headphones have a much higher noise floor and there are no commercial recordings I'm aware of with a noise floor lower than -60dB, which is 100-1,000 times higher than even relatively cheap DACs!
> 2. Watts is going on about noise/distortion far lower than the sound of two hydrogen atoms colliding though, 1,000 - 100,000 times lower! What in the real world could even create such a ridiculously low sound pressure level? Maybe a quark scratching it's nose? You think it's even possible that a sound pressure wave at that level could be propagated, that your speakers/headphones have anywhere even vaguely near that resolution or that the billions of molecules which make up your eardrum could be in any way affected by it?
> ...



What people are missing is that some designers are also salesmen. Some are  even gifted and empathic...
Dealing with measurements most of them are simulated/calculated ones and in digital domain: Noise shaping, Complex Power relative to Carrier,etc...
As an audio layman with alive background in digital transmission it took me quite some time and curiosity for making up my mind. Therefore I perfectly understand why some headfiers may become hard believers.
Nonetheless, I value a lot feedbacks from users even if biased since they are quite informative at different levels.
I also value a lot this science forum since it has been opening my eyes. Thanks


----------



## Triode User

gregorio said:


> Right there we have a large part of the problem, a part which I've mentioned numerous times but which is consistently ignored, the BS marketing pervasive in the audiophile world and the reason it's employed, to create biases which hopefully will affect audiophile's perception. You've obviously have substantial respect for Rob Watts but based on his posts (this one quoted previously, for example), I have no respect for him at all, in fact quite the opposite! All it takes to realise this, as I've said before, is a few basic facts and the application of a little logic. I could go through his post point by point demonstrating it to be nonsense but let's just take the main point, that of noise/distortion down to -200dB (and beyond) being audible. The basic fact to know is that if 0dB is equivalent to the sound level of a truck driving past a few meters away, then the approx -144dB limit of 24bit would be roughly equivalent to the to the sound level of two hydrogen atoms colliding! This should raise a couple of questions:
> 
> 1. Assuming you realise that a sound wave is a pressure wave which travels through air, how would the tiny pressure produced by two hydrogen atoms colliding be enough to move the billions of air molecules necessary to propagate a sound wave in the first place? - Answer - It couldn't, there is no way that could be achieved. In theory, the noise created by just the sub-atomic particles (electrons) colliding inside resistors and other electrical components in a DAC limits the lowest noise floor achievable to about -132dB but in practise no one has achieved this. The lowest noise floor of any DAC on the market that I'm aware of is about -124dB, roughly 10 times higher than the theoretical limit of 24bit. In practise we don't have to be even slightly concerned about this, as your speakers or headphones have a much higher noise floor and there are no commercial recordings I'm aware of with a noise floor lower than -60dB, which is 100-1,000 times higher than even relatively cheap DACs!
> 2. Watts is going on about noise/distortion far lower than the sound of two hydrogen atoms colliding though, 1,000 - 100,000 times lower! What in the real world could even create such a ridiculously low sound pressure level? Maybe a quark scratching it's nose? You think it's even possible that a sound pressure wave at that level could be propagated, that your speakers/headphones have anywhere even vaguely near that resolution or that the billions of molecules which make up your eardrum could be in any way affected by it?
> ...



I have unsubscribed to this thread but just popped in to look at the general tone.

My respect for Rob Watts is primarily because I like the sound of his Blu2 and Dave combined MScaler/DAC. You of course will be of the persuasion that any decent in spec DAC does the job fine and if a DAC sounds different it is because someone has fiddled with sound signature or because the output levels have not been correctly matched. I have suggested you listen to a Blu2 with Dave and you have merely been scornful and piled on more condescending mockery. A more adult response might be to say that if the opportunity arises you would be interested to hear the Blu2/Dave combo and that you would do so with an open mind. But, well, hey ho, the open mind bit means that will never happen.

The published spec of the Dave is :-

*Frequency Response:*
20Hz to 20kHz +/- 0.1dB
*THD +N:*
127.5dB (AWT)
*Channel Separation:*
>125dB @ 1kHz
*Dynamic Range:*
127.5dB (AWT)


----------



## ev13wt

Ya, my soundcard can do that. 

Frequency response: <10Hz–90kHz, –3dB (96kHz sampling). THD at –3dB: 0.0003%, line out; 0.001%, headphone out. Signal/noise: 124dBA, line out; 110dBA, headphone out. A/D input S/N: 118dBA. A/D input THD at –3dBFS: 00002%.
Read more at https://www.stereophile.com/content...soundcards-specifications#ZhualMpJv0UHI1AH.99

See, my card goes up to 90KHz, so I have you beat on that alone. 






Its that careful line that must be treaded. Ya know, the one between sales and supporting companies that pay money to this site. Some people don't want to lose that money. Maybe a reason this thread ended up here where nobody looks.


The people that form the "headphone market" public opinion can choose what they want - all the money and all the snake oil, or they put their foot down and throw out snake oil in general. Its a problem of motivation for people new to the market. Would you join up to a site where BS flies, is supported and recommended? Where you as a newb cannot see anything different to the 27 reviews you just read? Its very close to "beats by dre" being the "best thing ever".

If you read this site as a newb, you NEED 5K in gear, including ... special power cords and high end interconnects to have good sound. I mean, people actually believe and spread the BS all over the internet, reviews, blogs... So sad. (I have no problem with wanting expensive gear.)


This is the reason I argue so emotionally when BS is on the table; Kids or newbs need about 150 to 500 bucks to get 95% of high fidelity sound. The should know this. Without having to sort through cable sound bs.

But I am only a simple man, what do I know about big business?


----------



## gregorio (Oct 18, 2017)

Arpiben said:


> [1] What people are missing is that some designers are also salesmen. Some are  even gifted and empathic...
> [2] Dealing with measurements most of them are simulated/calculated ones and in digital domain: Noise shaping, Complex Power relative to Carrier,etc...



1. Absolutely! The other problem is that in today's world, where digital audio technology was effectively perfected beyond the limits of audibility quite a few years ago, boutique audiophile manufacturers have no where to go, no upgrade path which brings us closer to audible perfection because that's not only already been achieved but is now achieved routinely at a tiny cost. At bulk trade prices, an audibly perfect DAC chip costs about $1.50! Pretty much the only direction audiophile manufacturers can go, if they are to stay in business and charge more than a very modest amount for their digital audio products, is to lie, to misrepresent or dispute the facts, science and engineering. The result is an audiophile product which, in it's attempt to differentiate itself from cheap products, does something differently and ends up either not achieving the basic standards of engineering that cheap products achieve or, actually improves upon the basic standards but those improvements are inaudible.

2. Yep, the problem so often in the audiophile world is one of relative scale. What does say -200dB really mean and how does it relate to the real world? In the digital realm we can have and calculate any arbitrary low level down to minus infinity dB but back in the real world, where we have to convert those numeric values into an analogous electrical current and then an acoustic sound wave, those digital numbers/values are completely un-convertable even in theory! Sure, we use 64bit processing for mixing audio but there's two good reasons for that: 1. Pretty much all CPU chip manufacture today is based on a 64bit architecture, so it's cheaper to employ 64bit for the significant processing required when mixing than some lower bit depth which would still be sufficient. 2. Again scale! A consumer DAC has 2 channels of digital audio, relatively modest processing requirements for those two channels and therefore digital noise artefacts which should be well below audibility (assuming basic competent design), even at relatively low bit depths. 64bit processing maintains digital noise artefacts well below audibility in any commercial mixing eventuality and any commercial mixing eventuality includes some feature film workflows which can employ up to 1,200 or so digital audio channels/paths, plus numerous processors on many of them. Distortion/Noise artefacts down at silly numbers (-200dB and beyond) are therefore valid in commercial mixing as we could be compounding those artefacts many thousands of times but of course, this is an entirely different scale to stereo consumer playback!!



Triode User said:


> [1] A more adult response might be to ....
> [2] *Dynamic Range: *127.5dB (AWT)
> [3] I have unsubscribed to this thread ...



1. IMHO, a "more adult response might be to" learn some basic facts and apply some simple logic rather than swallowing hook, line and sinker whatever nonsense an audiophile product designer come up with to get you to buy that product.

2. Unweighted, that DR figure equates to or is poorer than the 124dB I mentioned above. This means, as 0dB is the highest possible value in digital audio, that the Dave is potentially capable of resolving down to somewhere around -124dB. But, that -124dB limit of the Dave is roughly 6,300 times higher than the -200dB noise/distortion Rob Watts claims to be hearing. So, in order for him to even potentially be hearing what he claims, he must obviously be using some other DAC with a massively better dynamic range than the Dave! Oh dear, to admit that is not great from a Chord marketing perspective is it? Not to worry though, there is no DAC which is 6,300 times better than the Dave, there's probably none even 2 times better and that's why what he claims to be hearing is utter nonsense. Note that we arrived at this obvious conclusion with just a basic fact or two (the DR spec of Dave plus an understanding of what it means) along with some simple logic. Nothing which is beyond even an average school child, let alone an adult!

3. The more "adult response" might have been to try and understand why you found some of the comments offensive and why they were posted. At the very least, an "adult response" IMHO, would have been to ignore those particular comments/posters but still open your mind to some of the others and some actual facts, rather than steadfastly remaining close minded to anything other than marketing BS and a demonstrably false belief in the accuracy of your perception. However, you're obviously unable to open your mind and/or unwilling to face the uncomfortable truths that those actual facts represent, which incidentally is another classic example of what I mentioned previously; accusing others of what audiophile themselves are most guilty of. So while you unsubscribing from this thread is not IMO an "adult response", it is somewhat understandable, if somewhat lamentable.

G


----------



## Triode User

gregorio said:


> 1. Absolutely! The other problem is that in today's world, where digital audio technology was effectively perfected beyond the limits of audibility quite a few years ago, boutique audiophile manufacturers have no where to go, no upgrade path which brings us closer to audible perfection because that's not only already been achieved but is now achieved routinely at a tiny cost. At bulk trade prices, an audibly perfect DAC chip costs about $1.50! Pretty much the only direction audiophile manufacturers can go, if they are to stay in business and charge more than a very modest amount for their digital audio products, is to lie, to misrepresent or dispute the facts, science and engineering. The result is an audiophile product which, in it's attempt to differentiate itself from cheap products, does something differently and ends up either not achieving the basic standards of engineering that cheap products achieve or, actually improves upon the basic standards but those improvements are inaudible.
> 
> 2. Yep, the problem so often in the audiophile world is one of relative scale. What does say -200dB really mean and how does it relate to the real world? In the digital realm we can have and calculate any arbitrary low level down to minus infinity dB but back in the real world, where we have to convert those numeric values into an analogous electrical current and then an acoustic sound wave, those digital numbers/values are completely un-convertable even in theory! Sure, we use 64bit processing for mixing audio but there's two good reasons for that: 1. Pretty much all CPU chip manufacture today is based on a 64bit architecture, so it's cheaper to employ 64bit for the significant processing required when mixing than some lower bit depth which would still be sufficient. 2. Again scale! A consumer DAC has 2 channels of digital audio, relatively modest processing requirements for those two channels and therefore digital noise artefacts which should be well below audibility (assuming basic competent design), even at relatively low bit depths. 64bit processing maintains digital noise artefacts well below audibility in any commercial mixing eventuality and any commercial mixing eventuality includes some feature film workflows which can employ up to 1,200 or so digital audio channels/paths, plus numerous processors on many of them. Distortion/Noise artefacts down at silly numbers (-200dB and beyond) are therefore valid in commercial mixing as we could be compounding those artefacts many thousands of times but of course, this is an entirely different scale to stereo consumer playback!!
> 
> ...



G,  We are unlikely to reach common ground on many items as I think we both have an element of closed minds relating to it. You might not believe it but I do have an effective BS filter and all of my cables are standard no phool copper from a reel cut and made by me. Likewise there is not a single non stock power cable anywhere in my system. However, on a different thread on Head-Fi, Rob Watts has been explaining what he is doing. I readily admit I do not have the knowledge to follow it. You may well say that many existing chips can do the same or better and you can either splutter with laughter or whatever if you read these two posts, but his devices do sound different (to me, not in level matched tests, just through typically 9 hours per day of listening, so I accept the fallibility of that statement from your perspective). 

www.head-fi.org/threads/watts-up.800264/page-24#post-13787487

www.head-fi.org/threads/watts-up.800264/page-24#post-13787531


----------



## Darren G

About the only thing I feel like adding ...

Spending some $ on hearing live music is an ear-opener.  Odds are the event is amplified, mics, cables galore, and nobody is fretting about the purity of the copper in the wires.

There is at least one key difference.  It really is a large room, and a related second... we can turn our heads up, down, left, right.  HPs don't recreate this.  Speakers in small rooms in homes, not entirely either.  There are some other psychological differences as well, like crowd energy, and that we enjoy the music and don't obsessive over the noise floor of the amps, mixers, etc. at a live event, but anyway...

Personally I'll just bank some of my $ for live music and am content with my good old cheap USB cables.


----------



## Don Hills

Triode User said:


> ...  I do have an effective BS filter ... Rob Watts has been explaining what he is doing. I readily admit I do not have the knowledge to follow it....



The effectiveness of your BS filter is determined by your level of knowledge of the subject being BSed. 
Again taking the Rob Watts "200 dB" example:
(a) He's talking about something else entirely and was misquoted
(b) He's exaggerating for effect and hasn't stopped to think how dumb it sounds
(c) He's deliberately BSing. 
Personally, if I don't know enough about a subject to determine which is the most likely answer, I just say "Uh huh" to myself and wait for someone to explain it in small enough words that I can understand it. 
You've had a couple of good explanations of why hearing noise at 200 dB below the signal is nonsensical. I've just read through the referenced presentation and I agree, the best that can be said about it is that it is misleading.


----------



## Clive101

May I ask a scientific question...?


----------



## ev13wt

Clive101 said:


> May I ask a scientific question...?



Not in the science forum! /joking


----------



## gregorio

Triode User said:


> [1] You might not believe it but I do have an effective BS filter ...
> [1a] ... Rob Watts has been explaining what he is doing. I readily admit I do not have the knowledge to follow it.
> [2] www.head-fi.org/threads/watts-up.800264/page-24#post-13787487
> [3] www.head-fi.org/threads/watts-up.800264/page-24#post-13787531



1. Of course we'd all like to believe that, none of us want to believe we can be easily duped/scammed. The problem is that music recording/reproduction covers a number of fields all of which can be pretty complex when we dig a bit deeper. This provides almost endless marketing BS opportunities which no one who hasn't dug deeply would be able to filter. In which case all you can do is try and judge if the person (in this case Rob Watts) is a nice man who is not deliberately trying to dupe you. Alternatively, you could actually dig a bit deeper and base your filter on some actual facts, rather than just intuition. And that's largely why this sub-forum exists.
1a. Case in point, without that knowledge your BS filter is a wide open door. Instead of facts, all you have is intuition and assumption, both of which are prime marketing targets and have been pretty much since modern marketing was invented over a century ago.

2. As I said, I can go through that post point by point, provide some real facts/context and demonstrate why most of them are complete BS but I've already done that with the main point so I'll move on to the next one, unless you've got a specific point or two you'd like me/us to pick up on?

3. The points in the first pane "Measurements" are actually all pretty accurate, shame his subsequent panes go on to ignore/pervert some these initial points! The second pane - "Some Examples - Noise floor modulation" - is nonsense. It breaks the penultimate point in his Measurements pane, a distortion product at -150dB could not possibly correlate with any reliable listening test because a signal at -150dB is about 20 times lower than the lowest signal his DAC is even capable of outputting in the first place (according to the dynamic range specs you posted) and incidentally, at least 31,000 times below the noise floor any commercial recording! The "Dave Noise-Shaper Performance" is equally nonsense, actually that's not true, in an absolute sense it's even more nonsensical because that -301dB is about 700 million times below what his DAC can actually output and even noise-shapers many millions of times higher in level can "perfectly reproduce the amplitude" of even the very smallest reproducible signal. I've no issue with the "Jitter Test" pane, except to mention that even cheap DACs reduce jitter artefacts to well below the limit of Dave's ability to reproduce. And the same is true of the next pane. The next pane, "16-bit -90.3dB", I'm not quite sure what this is trying to prove, what the actual test is or how this result would stack up against a much cheaper DAC. The last pane - no, I've got no questions, I think I can work out for myself why he's quoting signal levels which cannot even be output by his DAC, let alone be audible.

G


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## pinnahertz

Triode User said:


> G,  We are unlikely to reach common ground on many items as I think we both have an element of closed minds relating to it. You might not believe it but I do have an effective BS filter and all of my cables are standard no phool copper from a reel cut and made by me. Likewise there is not a single non stock power cable anywhere in my system. However, on a different thread on Head-Fi, Rob Watts has been explaining what he is doing. I readily admit I do not have the knowledge to follow it. You may well say that many existing chips can do the same or better and you can either splutter with laughter or whatever if you read these two posts, but his devices do sound different (to me, not in level matched tests, just through typically 9 hours per day of listening, so I accept the fallibility of that statement from your perspective).
> 
> www.head-fi.org/threads/watts-up.800264/page-24#post-13787487
> 
> www.head-fi.org/threads/watts-up.800264/page-24#post-13787531


The problem is that when someone makes several statements that are not true, or not backed by anything but their own "theory", it erodes their authority and credibility.  This guy Watts is a treasure-trove of that sort of thing.

But when you say things like, "I readily admit I do not have the knowledge to follow it." ...and..."but his devices do sound different (to me, not in level matched tests.....)" it makes some of us wonder you'd bother trying to support Watts and put yourself in the same line of fire.


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## Triode User (Oct 18, 2017)

gregorio said:


> 1. Of course we'd all like to believe that, none of us want to believe we can be easily duped/scammed. The problem is that music recording/reproduction covers a number of fields all of which can be pretty complex when we dig a bit deeper. This provides almost endless marketing BS opportunities which no one who hasn't dug deeply would be able to filter. In which case all you can do is try and judge if the person (in this case Rob Watts) is a nice man who is not deliberately trying to dupe you. Alternatively, you could actually dig a bit deeper and base your filter on some actual facts, rather than just intuition. And that's largely why this sub-forum exists.
> 1a. Case in point, without that knowledge your BS filter is a wide open door. Instead of facts, all you have is intuition and assumption, both of which are prime marketing targets and have been pretty much since modern marketing was invented over a century ago.
> 
> 2. As I said, I can go through that post point by point, provide some real facts/context and demonstrate why most of them are complete BS but I've already done that with the main point so I'll move on to the next one, unless you've got a specific point or two you'd like me/us to pick up on?
> ...



Thanks for taking the trouble and time to reply.


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## ev13wt

My BS filter is only an indicator. I adjust the BS filter all the time.

I am easy to dupe in some areas, not so easy in others.


----------



## gregorio

ev13wt said:


> My BS filter is only an indicator. I adjust the BS filter all the time.



Try this:







G


----------



## Triode User

I have had a lucky escape. No one warned me about Sound Science when I joined Head-Fi. But I have amassed some points collected elsewhere and have used them in exchange for the code for the secret door out of Sound Sciece. 

I am blinking slightly in the daylight as I adjust to being back in the real world. 

Take care and never forget that although you think you know what you are talking about it might just turn out that you don’t. 

See ya guys.


----------



## pinnahertz

Triode User said:


> I have had a lucky escape. No one warned me about Sound Science when I joined Head-Fi. But I have amassed some points collected elsewhere and have used them in exchange for the code for the secret door out of Sound Sciece.
> 
> I am blinking slightly in the daylight as I adjust to being back in the real world.
> 
> ...


Well, maybe he's really gone and won't see this.  But anyway, a real "sound scientist" takes the audiophile "observations" seriously, tries to learn about them, and explain where they come from.  We often find out that we don't fully know what we thought we knew, but it's all about learning.  What we don't do is accept a belief without proof that it even exists.  

And thanks, but I think the light of truth is brighter.


----------



## bigshot

Return to Plato's cave, Triode!

It was nice to have a little philosophy for a brief while.


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## JaeYoon

pinnahertz said:


> Well, maybe he's really gone and won't see this.  But anyway, a real "sound scientist" takes the audiophile "observations" seriously, tries to learn about them, and explain where they come from.  We often find out that we don't fully know what we thought we knew, but it's all about learning.  What we don't do is accept a belief without proof that it even exists.
> 
> And thanks, but I think the light of truth is brighter.


Here's the thing too everyone in these debates for cables and such wants to win. Regardless of the outcome of the debate. He thinks he won.

But most important thing is the one who debates to learn and to share information.

I honestly like this thread as I learned a lot from people here. Including those who support robb watts. Honestly rarely read stuff like this on regular headfi.

"Just bro you gotta listen to the dac with the effect audio thor II in balanced to hear the difference dude!!".

I applaud you all and you too @gregorio for taking the time to put out posts with lots of information to gain.

I honestly did not come into this thread to win battles against audiophiles or the like. Just to learn from each side.


----------



## JaeYoon

@gregorio found another post one of Mr.Watts post. But this time he posted that he set an "Non-Audiophile" Audio Engineer. Keep in mind folks he specifically worded Non-Audiophile engineer. Into a single blind testing for RF Interference affecting the sound.

For those of you interested check this out!







I would also be very very eager to see if Mr.Watts can do a DBT on a properly ripped 320 K (freaking overkill) QAAC encoded AAC. No cherrypicking FAAC encodes. To a 16 bit FLAC file.
Pass the test consistently in Foobar with ABX plugin, and upload these beautiful log files. He can use his BluDave if he wants to too! Feel free to hook that baby up! I'm eager to see his log files as well!
See if his bold claim is up to par.


----------



## castleofargh

not sure the bashing and rounds of victory are helping anything. what's important is getting our facts right, holding a rational until the end, and no claiming anything without actual knowledge that it is true. 

Watts markets his product, even if everything he believes in is true, he's going to exaggerate the subjective side of things. not that I like it, but most people do exactly that all year long in the industry. I personally find how he sees correlations between digital theory and subjective impressions to be out of this world on occasion. but because he's clearly someone who knows his digital theory, I'm tempted to think that maybe things get partially weird because he's addressing us informally, so he lets things slip that he himself probably wouldn't let pass in an actual research paper for example. how he's usually answering newbie questions is also in a factor in how much simplification he's going to apply. can't really blame him for that. the same way I don't find it in me to blame those who say that USB cables make no difference, despite how obviously it's untrue when claimed in such a categorical way. I let it go because those guys are trying to explain signal transmission to people who understand neither wave theory, electrical laws, digital theory, or clearly themselves, given how they believe impressions of sound is sound, and sighted test is a reliable proof. so aside from sending them to school for a month or 2 and then giving the proper answer, we have to use simplified views and over-generalizations. no other way TBH. 
it's the wrong with good intentions. still wrong and ultimately it would be nice to deal with it. but given the choice between "all USB cables sound the same, use your money on more relevant parts of the playback system" on one hand. and someone saying that a 600$ usb cable was needed to get good fidelity, with close to zero solid evidence and more than shaky rational based on poorly controlled anecdotes and jumping to conclusion. the lesser evil is obvious.


as for measurements, when something changes at -140dB everybody with half an understanding of human hearing knows for a fact that it is not the cause of a change in soundstage or whatever.  so *if* there is indeed change in the sound at an audible level(and a proper demonstration of that is required before claiming anything), it seems obvious to look instead at what reaches audible levels in the altered implementation. which means doing more measurements, and perhaps double checking the listening test. 
and here I use my clairvoyance skill to say that if a change is audible and not imagined, something will show up in the 0 to -90dB area on some variable at some point.

it would be way more relevant to those discussions to look for and find those variables instead of making crap rationalizations to justify how a cable changed sound(maybe). 

so it goes like this:
1/notice a change
2/ use any relevant method to make sure it's not bias or placebo, but indeed sound and only sound that's changing.
3/ measure stuff and look for anything that could be within human threshold of audibility while listening to music(so not pretending like -200dB bull crap is significant). when found, congrats we have demonstrated and defined an objective change susceptible to be the cause of the audible difference.
4/ for the warriors only: try to consider the means to test those found variables independently, maybe improve on them without ruining everything else, and help understand what was wrong and how to avoid it in the future. then maybe draw conclusions about what cable specs we need. 


and the lazy dysfunctional version for those who wish to feel right a lot more than they wish to actually find out the truth:
1/ notice a change
2/ get any idea
3/ cherry pick anything vaguely objective that could probably agree with my idea
4/ conclude that I was right all along. 

let it be known that I have very little love or respect for that second "method".


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## gregorio (Oct 19, 2017)

JaeYoon said:


> ... found another post one of Mr.Watts post



Good catch! This one statement explains/encapsulates pretty much everything: "*I on the other hand, have consistently heard errors that are much smaller than the ear's ability to detect from the threshold of audibility POV, and the reason these small errors are audible is down to the brain's processing of the data from the ear, and the threshold of audibility tests do not cover processing*". - Very broadly speaking, I agree with this statement ... BUT, I say "very broadly" because he's been very imprecise and confused some of the terms he's used and it's extremely hard to believe this is not a tactic deliberately designed to mislead for his personal profit! At the very least, it's very misleading/misinformed with the very happy coincidence that it benefits him financially. If we change his wording slightly and correct his confused terminology, then what he's saying entirely agrees with the science and known facts:

_ "I on the other hand, have consistently heard *perceived* errors that are much smaller than the ear's ability to detect from the threshold of audibility POV, and the reason these small errors are audible *perceivable* is down to the brain's processing of the data from the ear *[+ other senses and memory]*, and the threshold of audibility tests do not cover processing." _

In other words, if we know there are errors it's entirely possible to perceive a difference regardless of whether the difference is audible and even regardless of whether those errors cause any difference in the actual sound waves themselves. We've had proof of this quirk of perception for at least 40 years due to the McGurk Effect (here's an example), which demonstrates "night and day" differences in perception even when there are none. In other words, we don't need to change a USB cable, a DAC or indeed make even the tiniest of changes to the actual sound entering the ear for "night and day" differences to be perceived. The only change required to potentially perceive this difference is a change in knowledge (visual information in the case of the McGurk Effect) which is completely unrelated to sound.

Rob Watts is effectively agreeing with us, there is no audible difference, the difference is purely down to the listener's "brain processing"/perception/imagination, although he's worded it to imply the exact opposite and thereby created the knowledge/bias which by itself could influence the "brain's processing"!! Clever (or beneficially coincidental if you wish to be particularly charitable).



Triode User said:


> But I have amassed some points collected elsewhere and have used them in exchange for the code for the secret door out of Sound Sciece.
> I am blinking slightly in the daylight as I adjust to being back in the real world.



You've "amassed" some marketing BS points collected elsewhere, completely eliminated or even inverted your "BS filter" and are "blinking slightly" from the powerful artificial light which you seem to fervently believe is real daylight. Your "real world" is actually just a small sub-group of people who believe they are superhumans, capable of identifying differences at the individual sub-atomic particle level (which are not even being produced by your sound systems in the first place). To everyone else, your "real world" is a fantasy world and the actual real world is quite different from a superhuman populated Marvel comic! I understand, the real world and actual daylight indicates that you've effectively purchased a surprisingly cheap DAC housed in a shockingly expensive case and if I'd been so duped out of so many thousands then I too might be tempted to close my mind to the real world and escape to a fantasy world!

G


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## Clive101 (Oct 19, 2017)

Ok here comes my question but I feel some of you scientists have touched on this over night.

Is it possible for inaudible noise ( mains, RF, computer- server noise or any noise interference ) to affect the Sound Quality we perceive to hear ( with our ears and or brain )...?


----------



## Darren G

gregorio said:


> ...We've had proof of this quirk of perception for at least 40 years due to the McGurk Effect (here's an example), which demonstrates "night and day" differences in perception even when there are none...



I saw that, and makes me want to bang my head on a table 

First, I own several concerts on blu ray, for the very reason that I'm 100% aware that engaging the visual side of my brain affects my auditory experience.  I.e., Yea, I enjoy music in a different way when I can see the performers at the same time.  Hardly news!

Second, it makes me want to bang my head on the table, taking one fact, and because it's true, using it as the gateway to try and prove something else, because there is an apparent (even if only weak) similarity.

Third, it's also well understood that if someone is shown a visual that triggers a belief it's going to sound better, that it often does.  We could replace this with medicine.  If it has a medical sounding name, looks like medicine, if someone is told this medicine will do x, y, z, etc., it can affect their perception, which is exactly why the need for DBT's.  The placebo effect is hardly news either.

/sigh


----------



## Clive101

Darren G said:


> I saw that, and makes me want to bang my head on a table
> 
> First, I own several concerts on blu ray, for the very reason that I'm 100% aware that engaging the visual side of my brain affects my auditory experience.  I.e., Yea, I enjoy music in a different way when I can see the performers at the same time.  Hardly news!
> 
> ...



Yes I agree, no need to bang your head on the table please. I was waiting for that answer you may have missed my point. 

Please let me rephrase the question if it were a blind person listening to the music..?


----------



## Darren G (Oct 19, 2017)

Clive101 said:


> Please let me rephrase the question if it were a blind person listening to the music..?



Hi Clive,

Not sure you are going to get any definitive answer, but if something is inaudible, then well ya know, it's inaudible.

Off hand that leaves -

1.) If something is affecting your mood, distracting your brain, and so on, sure, it may affect your focus and perceptions in general, including enjoyment of music.  Drinking too much can affect your perception 
2.) Air pressure on the ears affects your ears, even if it's just a case of being in an airplane and that ear pop experience.


----------



## Clive101 (Oct 19, 2017)

Darren G said:


> Hi Clive,
> 
> Not sure you are going to get any definitive answer, but if something is inaudible, then well ya know, it's inaudible.
> 
> .



That's the issue I looking for the scientists in this forum to give one ( an answer to the question ) yes no or maybe...? If possible


----------



## JaeYoon

Clive101 said:


> That's the issue I looking for the scientists in this forum to give one ( an answer to the question ) yes no or maybe...? If possible


No one in here is a scientist (from what I know) They use science as a tool to gauge decisions.

A blind person listening to music will still hear what the limits of their ear can hear.


----------



## Clive101

JaeYoon said:


> No one in here is a scientist (from what I know) They use science as a tool to gauge decisions.
> 
> A blind person listening to music will still hear what the limits of their ear can hear.


MMM no scientists that's a shame I am sure there are one or two hiding somewhere but thank you for the information we have non scientists using science as a tool to gauge decisions.

My question also included the brain perception of inaudible noise and if that affected Sound Quality perceived.


----------



## Arpiben (Oct 19, 2017)

@Clive101 ,

1. An inaudible noise can be heard/perceived if it interacts with other frequencies and

creates a new frequency in the audible range: IMD intermodulation,frequency beating (mixing),
modulates in amplitude or frequency the existing signal,
etc (certainly more cases I don't know)
2. Dealing with neuroscience and sound cues you may have a look at C.Mendonça paper:
_*A review on auditory space adaptations to altered head-related cues.*_
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4110508/pdf/fnins-08-00219.pdf


----------



## Darren G

Clive,

There are some here that have deep backgrounds in sound science.  I don't claim to be one, so just IMHO's from me, but...

Still, I think it's fair to say that some people lean more toward the side of 'I don't entirely trust my own perception, I know I can be fooled, I'm aware of the placebo effect, etc.'   It's a different starting point than the lean toward 'I trust my own perception until proven otherwise' (with the caveat that on the extreme end of the scale, there is no proof that would alter the belief).


----------



## JaeYoon

Darren G said:


> Clive,
> 
> There are some here that have deep backgrounds in sound science.  I don't claim to be one, so just IMHO's from me, but...
> 
> Still, I think it's fair to say that some people lean more toward the side of 'I don't entirely trust my own perception, I know I can be fooled, I'm aware of the placebo effect, etc.'   It's a different starting point than the lean toward 'I trust my own perception until proven otherwise' (with the caveat that on the extreme end of the scale, there is no proof that would alter the belief).


Yeah once we know the marketing and how audio companies including high end ones operate to stay in business.

The ones who know they can be fooled if they buy. Tend to be the ones who save a lot of money.

Audiophile boutique companies are seeking out customers who already know in their mind, they know what they hear and they read the marketing packaging and in their minds they are hearing what they read.

For the ones here who have experience and knowledge on audiophoolery. You can't fool them, hence the audio companies are not targetting them. They are targetting those who trust their perception and ones who believe their ears.

All those companies with low volume sales need to make money somehow. Getting customers to believe what they read is key. The McGurk effect that gregorio posted.


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## ev13wt (Oct 19, 2017)

Clive101 said:


> Ok here comes my question but I feel some of you scientists have touched on this over night.
> 
> Is it possible for inaudible noise ( mains, RF, computer- server noise or any noise interference ) to affect the Sound Quality we perceive to hear ( with our ears and or brain )...?



Yes, no, depends. This could be its own thread.

You said "inaudible". So it must be negative dB. So you cannot hear it.
Can it influence the sound quality? Depends on everything from how the PSU section is setup, amp topologies etc. If it is built "correctly", then none of the things you mentioned should influeze SQ.
But in the real world, there are "mistakes" and "cost factors" to consider; I have a little USB adapter DAC (Logitech) and everytime I move it in the USB port, I can hear "scratching" in the headphones. So I don't move it...

If the noise is high enough in level, but still being "masked" by other, higher amplitude sounds - It does enter your brain and gets analyzed, but you cannot actively hear the noise, but it is there and can affect other things. What type of noise? What frequencies does the noise cover? Are there frequencies that are in the noise also in the signal?


There are around 7 different distortion "factors" says Douglas Self.
https://www.eetimes.com/document.asp?doc_id=1274876

Start here?

Then, we learn about the noise that ICs themselves make and more!
http://www.electronicdesign.com/analog/what-was-noise


----------



## castleofargh

Clive101 said:


> That's the issue I looking for the scientists in this forum to give one ( an answer to the question ) yes no or maybe...? If possible


"yes no, maybe, IDK, can you repeat the question? ...." 

warning/!\ not a scientist!!!!! not even a world leading specialist in shrimps, so maybe my post isn't relevant. 

 to try and clarify your question, do you believe that if you send a signal at -10dB SPL in your room for 1000 hours, it will have an impact on your life or your general experience of music? and will you be able to tell if it is a positive or negative impact? given how we humans perceive anything thanks to levels of energy with the appropriate sensor, ludicrously small energy could have ludicrously small impact(so night&day claims coming from that would be silly), or simply not register at all if too small. given that a "quiet" room will probably still have many noises around maybe 25 to 40dB, how relevant can the -10dB signal be? and same question when you're listening to music at 80 or 90dB. one banana may be relevant alone, but in a pile of thousands of bananas, how much impact can we expect from adding or removing 1? who would notice if they aren't told or don't see us taking the banana?
on the other hand, if I keep telling a guy that there is a banana thief, how much do you wanna bet that he'll start to doubt if the pile changed, and that at some point he might even become convinced even if the bananas were left alone? 
why look for weirdo explanations when human preconceptions are proved to lead to exactly the symptoms you try to justify? that's like having a traffic accident, and looking only for cues that a vehicle had a malfunction when we know that statistically, it's almost always a human error. sure a tire could have blown up or the break were bad or the CIA sent a signal via a super satellite to create the accident. endless possibilities, but in the long run when looking into accidents, human error is still the leading cause by a good margin, and it would be strange/dishonest to pretend like it's not even a thing.  


another idea would be strong energy, but out of the audible frequency range. that could and can have a physiological impact. like how really high level ultrasounds can be felt on the skin, and also damage your ear while if the frequency is high enough, you won't actually "hear" it. the same way ultra violets can burn your skin but you don't feel or see them, at least not instantly. 

so the answer to your question is obviously yes. of course many things can have an impact that will become conscious despite not being noticed when we try to. like high level of radiations that will kill us in the long run, or eating something that will at some point destroy our liver. or simply listening to something without any cue, then listening again after being told what to listen for(there are some funny games about speech recognition like that, when the sound is garbage distorted stuff, but if you get to listen to the text once in a clear intelligible way, afterward you can't help but notice the sentence inside the garbage noise sequence.  so yes something could go unnoticed despite existing and potentially at some point having an effect depending on ... stuff. now does the possibility of such a thing happening in music, means that you can use it as an excuse to justify any mistaken impression when failing a blind test? sorry it doesn't work that way.


----------



## bigshot

Arpiben said:


> @Clive101 ,
> 
> 1. An inaudible noise can be heard/perceived if it interacts with other frequencies and
> 
> ...




Super audible frequencies can only distort audible sound. They don't add anything to the audible fidelity of recorded music. As the sound attacks in Cuba show, they can also be quite dangerous.


----------



## ev13wt

Maybe asking a different question: (To figure out what Clive is actually tring to figure out)

What type of noise, introduced to the system via connected ground or through the grid power affects the frequency response in such a way that audible IMD is created? What needs to happen that its does affect the response? (For instance, the smoothing caps after the diodes in the power supply section are way too small?)

Can a -40dB noise signal srew with the frequency response? A -20dB noise signal? Or is it just noise and the signal - both are heard "equally correct" and don't affect each other? (Not taking any other things like speaker response into account)? Can it somehow affect the amplitudes of the actual signal?

Basically, what needs to happen so that something like a *sigh* power cord can make an audible difference?


----------



## Darren G

ev13wt said:


> Basically, what needs to happen so that something like a *sigh* power cord can make an audible difference?



Credits to Schiit Audio manuals -

Question: Can I use an Audiophile Grade power cord with your gear?
Answer: Yes you can, but what about the thousands of feet crap wiring in your walls?

If we want to convince ourselves of something, we can.


----------



## Arpiben

bigshot said:


> Super audible frequencies can only distort audible sound. They don't add anything to the audible fidelity of recorded music. As the sound attacks in Cuba show, they can also be quite dangerous.



I was not considering those extreme cases such as ELF (extremely low frequencies) used in submarine communication or even some high SPL ultrasounds used purposely to provoke nausea and to avoid crowd in public places for instance.
Take a DAC with MCU running at 96MHz  an FPGA at 104MHz, Noise shaper frequencies,a PC noise, etc.. All frequencies may be inaudiblle but they may create audible frequencies in the audible range by combining (beating) each other.


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## gregorio (Oct 19, 2017)

Clive101 said:


> Is it possible for inaudible noise ( mains, RF, computer- server noise or any noise interference ) to affect the Sound Quality we perceive to hear ( with our ears and or brain )...?



Once you introduce the word perceive, then potentially anything is perceivable. The McGurk Effect demonstrates that we can hear a significant difference with two absolutely identical sounds. If we can perceive a difference when the actual difference is zero, then obviously we can also perceive a difference when the actual difference is higher than zero. If we remove the word "perceive" though, then we can talk about actual sound differences and what the ears can actually respond to, rather than about SOLELY imaginary perceptions. In which case, the answer is generally "no", it is not possible. There are some some potential exceptions to this general rule but it requires the inaudible noise to be very close to the audible threshold. However, this isn't the case with the discussions about Rob Watts or any competently designed DAC (at almost any price), as we are talking about noise many dozens, hundreds, thousands or even hundreds of millions of times below audibility. In fact, surprisingly often in audiophile discussions it's got absolutely nothing to do with audibility or inaudibility, because we're often talking about noise/signals which are too low in level to even be reproduced in the first place and obviously, if there's zero signal, there's zero difference and zero ability to affect any other sound! That's why we sometimes dismiss listening tests, because if we're talking about signals below reproducibility, then any difference heard can ONLY be due to our perception being fooled.

G

Edit: As per the previous posts in this thread, I am talking about "audibility" in terms of a threshold of signal level or loudness, not in terms of frequencies which are inaudible because they're beyond the freq range of human hearing and which would be audible if transposed.


----------



## bigshot

Arpiben said:


> I was not considering those extreme cases such as ELF (extremely low frequencies) used in submarine communication or even some high SPL ultrasounds used purposely to provoke nausea and to avoid crowd in public places for instance.
> Take a DAC with MCU running at 96MHz  an FPGA at 104MHz, Noise shaper frequencies,a PC noise, etc.. All frequencies may be inaudiblle but they may create audible frequencies in the audible range by combining (beating) each other.



I don't know if you happened to see the news reports on the Cuban sound weapon, but they had a recording of what it sounded like. It was described as sounding like crickets and the spectrum of the recording showed a mass of noise right around 6-8kHz. My guess is that the sound that was recorded was some sort of harmonic noise that accompanied the actual dangerous sound. Probably 2 or 3 octaves between them. The recording device they used likely wasn't able to record the actual frequencies that were doing the damage.


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## dzasta

What a thread! Took me a couple days but I read every post and finally all caught up now. The ignorance and stubbornness in this thread can be cut with a knife!

As a practicing EE (embedded system design), a few posts in I was already rolling up my sleeves..







But the patience of gregorio (how do you do it man), pinnahertz, arpiben, et al really made this thread a page turner (I learned so much personally). Of course you need the theorist's, clive's, cartma, et al to keep stoking the flame (discussion). The bottom line is this, one has to be open minded and needs to view things from the viewpoint of "I know nothing". 

*The #1 takeaway here is that there is no subjectively in a USB cable*. It either works, or it doesn't. Yes or No. 1 or a 0. Welcome to the digital world!!!

If you spend $500 on a USB cable, more power to you if that makes you _feel _better. Will it sound better? Nope. Placebo is such a powerful thing. Anyone heard of Monster Cable?

Men will be men. Pride, ego, ignorance, and even plain denial will always come into play. Frankly, a real man would accept that they were wrong and use that opportunity to learn and become better/smarter. But then this thread would have lasted only 10 posts tops. What fun is that?

Thanks again to everyone on this thread! Sure made me sign up (long time lurker)!


----------



## JaeYoon

dzasta said:


> What a thread! Took me a couple days but I read every post and finally all caught up now. The ignorance and stubbornness in this thread can be cut with a knife!
> 
> As a practicing EE (embedded system design), a few posts in I was already rolling up my sleeves..
> 
> ...


Welcome!! Enjoy your stay too
That's the thing. One of the "I know I hear differences" peoples left the thread thinking he won. But learned nothing.

The ones who truly win are ones who take advantage of the information that others share for those willing to learn.

The ones who share knowledge and information do have a lot of patience as we are going through various posts.

This is exactly why high end audio boutique companies are still alive. Because they look for people who's egos are about "I have golden ears and can hear the differences" ones who read the packaging and believe exactly what it is and defend the companies unethical business practices in selling products that do not solve any issues they claim too.

These audio companies feast and live off of audiophiles. In actual market they would not survive well with modern smartphones that also play audio.

I know every audiophiles spits at that idea. But in reality how many people worry about EMI and Jitter and other audiophile beliefs in better quality cables? The average middle class worker and below have no such time on their hands and use apple earbuds or even an entry level one and a smartphone.


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## castleofargh

dzasta said:


> What a thread! Took me a couple days but I read every post and finally all caught up now. The ignorance and stubbornness in this thread can be cut with a knife!
> 
> As a practicing EE (embedded system design), a few posts in I was already rolling up my sleeves..
> 
> ...


one of the issues with your point of view is that a guy somewhere has 2 cables and is sure they sound different(and maybe they do for some weird and probably extreme reason that could have nothing to do with the digital signal at all. who knows?). so to him what you talk about with 0 and 1 is plain ignorance as he holds the "proof" of the opposite in his hand.
it's like we discuss nominal playback chain with gear and cables to spec, but he discusses the one off exception in an exotic and possibly dysfunctional scenario. 
so at the start it's a pretty simple misunderstanding.

then it gets out of hand because the power of investigation and deduction wasn't fairly distributed among people. and there is nobody more confident than the guy who's just ignorant enough to see no reason to doubt(AKA most people most of the time). 
personally I'm ok to drop the statistical approach and look at one sample in specific conditions. I'm not ok to draw fantastic conclusions on the top of my head like many do, but I'm fine with observing one specific event or at least get data from one.  but somehow the most adamant advocates of expensive audiophile cables(all cables), are mostly people who don't measure stuff and don't setup rigorous listening protocols(so the type of people you can trust the least). that certainly doesn't help their cause. as a result, most of the time I'm left to test my own stuff which doesn't demonstrate anything as I would never spend 500$ on a 1meter wire. I'd sooner spend it on Nutella to try and bath in it. although I'd need maybe 100 to 150L and have no idea how I would ever get to the end of cleaning that.


----------



## pinnahertz

I used a cable on a job this summer that could handle 85kW (peak), had about .15 ohms resistance per 100', would work well up to 5gHz, lost no more than
0.345 dB/100ft at 100mHz, could handle up to 3000 volts continuous, and was made from solid high purity copper.  It wasn't an audiophile cable, it wasn't even an audio cable (but could certainly be used for audio, including speakers), but all of that cost about $2/ft, plus connectors (I used about 400ft, it's slightly more for shorter lengths).  

Here's the cut sheet:
http://www.rfsworld.com/WebSearchECat/datasheets/pdf/?q=LCF78-50JA-A7

Now, I grant you, it wasn't a USB cable, but if you can do all of that for $2/ft, why would anyone pay $170/ft for a USB, RCA, XLR, speaker  or any audio-related cable?  Or even $17/ft? Or even $7/ft? 

I guess there will always be a few things I don't understand.

BTW, the cable sounded great in a fully-sighted, uncontrolled non-A/B listening test.


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## gregorio

dzasta said:


> But the patience of gregorio (how do you do it man) ...



Welcome to the sub-forum! To answer your question, there's two reasons: Firstly, I was a uni lecturer for about 5 years and you can't verbally flog a student or expel them just because they can't grasp a relatively simple concept. So you develop great patience or you're out of a job. Secondly, I treat it like an exercise in logic, as this thread was started in a sub-forum which is particularly ant-science, just quoting laws of physics, facts and figures isn't likely to work, if they had a head for facts and figures they wouldn't believe the audiophile cable nonsense in the first place. So instead I've tried to use just the most obvious/observable facts and logic. 

Having said all the above, I don't always manage to maintain my patience here, as other frequenters of this forum will attest, and I've been officially warned on several occasions and had posts deleted for loosing my rag and getting too personal.

G


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## bigshot

i think we sometimes spend so much time talking about the rare exceptions that the rare sounds more common than the typical.


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## gregorio (Oct 20, 2017)

bigshot said:


> i think we sometimes spend so much time talking about the rare exceptions that the rare sounds more common than the typical.



Much of audiophile marketing is entirely based on the fear of the rare exception or even on the fear of an exception which is never applicable to audio/sound. Not only do we have to respond to these exceptions but in order to avoid being hypocrites and being guilty of what we accuse audiophiles of, we also have to be much more precise with our statements of fact by not making sweeping statements of absolute fact (without just cause) and being honest about the context of the facts and therefore the exceptions. 

I entirely agree with your statement though, as the above places much of the discussion and emphasis on the rare exceptions, giving the impression they're far more common than they really are. In this respect we're playing right into the hands of the marketeers and maybe we expect audiophiles to have a far more rational perspective than they've been conditioned to have and are capable of?

G


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## Clive101

Dear All,

Thank you for the answers and time taken to reply to my question it is greatly appreciated.

If I may ask another question.

Is it possible for inaudible noise ( mains, RF, computer- server noise or any noise interference ) to be affected by the design ( separate power wire, soldered joints, crimped joints, terminated ends, shielding, insulation etc ) and or the materials used ( copper, silver, plated copper, gold, terminated ends, shielding or insulation etc) within a USB cable...?

Thank you.


----------



## gregorio

Clive101 said:


> Is it possible for inaudible noise ( mains, RF, computer- server noise or any noise interference ) to be affected by the design ( separate power wire, soldered joints, crimped joints, terminated ends, shielding, insulation etc ) and or the materials used ( copper, silver, plated copper, gold, terminated ends, shielding or insulation etc) within a USB cable...?



Yes, most of those things can make some measurable difference in the output of the cable. Again though, there are two very serious problems with taking this fact as an isolated fact and out of context, as at the end of the day, a cable has to be connected to something. If we take for example RF noise, then a cable with more shielding will measure less signal interference at it's output than a cable with less shielding. HOWEVER, we plug a USB cable into a USB receiver circuit which removes that interference (due to CMR, as explained by Pinnahertz). So, the performance of the cable in this respect is effectively irrelevant to the sound which actually gets output, assuming: 1. The USB receiver unit is functioning correctly and 2. No extreme RF environment (very extreme and virtually unheard of in a consumer situation!). 

In other words, it depends on where we measure the performance of the cable, do we just measure the output of the cable itself or the output of whatever the cable is supposed to be plugged into and then compare those measurements to other cables plugged into exactly the same device? If it's the former, then we should get measurable differences, if it's the latter then differences from what you've listed should not only be inaudible, they should be un-reproducible! (with the same two caveats above; basic competency of DAC design and not a ridiculously extreme environment).

G


----------



## Clive101

gregorio said:


> Yes, most of those things can make some measurable difference in the output of the cable. Again though, there are two very serious problems with taking this fact as an isolated fact and out of context, as at the end of the day, a cable has to be connected to something. If we take for example RF noise, then a cable with more shielding will measure less signal interference at it's output than a cable with less shielding. HOWEVER, we plug a USB cable into a USB receiver circuit which removes that interference (due to CMR, as explained by Pinnahertz). So, the performance of the cable in this respect is effectively irrelevant to the sound which actually gets output, assuming: 1. The USB receiver unit is functioning correctly and 2. No extreme RF environment (very extreme and virtually unheard of in a consumer situation!).
> 
> In other words, it depends on where we measure the performance of the cable, do we just measure the output of the cable itself or the output of whatever the cable is supposed to be plugged into and then compare those measurements to other cables plugged into exactly the same device? If it's the former, then we should get measurable differences, if it's the latter then differences from what you've listed should not only be inaudible, they should be un-reproducible! (with the same two caveats above; basic competency of DAC design and not a ridiculously extreme environment).
> 
> G



Thank you for the reply

I have particular interest in the in measurable differences of inaudible noise which can pass though the USB cable (if that's possible) and how the design and materials of the USB cable could affect this inaudible noise.


----------



## Darren G

Clive101 said:


> Thank you for the reply
> 
> I have particular interest in the in measurable differences of inaudible noise which can pass though the USB cable (if that's possible) and how the design and materials of the USB cable could affect this inaudible noise.



There are some good posts earlier in this thread that emphasize a key point.  That cables pick up noise isn't news.  It's precisely the motivation behind digital signaling, to transfer the information while filtering the noise.  There were also comments made about the wires in the cable, the purpose of each, including why there are two data lines, reverse signals, so that common noise can be rejected (a common and well understood technique).  

There were also comments about the slight possibility of a ground loop, and maybe a comment about noise from the +5 volt line, with emphasis that any competent design should isolate. 

Still, if any of that concerns you, check out the Schiit Eitr.  For < $200 it will isolate all 4 wires from the source (usually a computer), including outputting it's own +5 volts. Even so, Schiit still just recommends using a good old (i.e, meets spec) USB cable in, and likewise a good old (meets spec) coax cable out.


----------



## Clive101

Darren G said:


> There are some good posts earlier in this thread that emphasize a key point.  That cables pick up noise isn't news.  It's precisely the motivation behind digital signaling, to transfer the information while filtering the noise.  There were also comments made about the wires in the cable, the purpose of each, including why there are two data lines, reverse signals, so that common noise can be rejected (a common and well understood technique).
> 
> There were also comments about the slight possibility of a ground loop, and maybe a comment about noise from the +5 volt line, with emphasis that any competent design should isolate.
> 
> Still, if any of that concerns you, check out the Schiit Eitr.  For < $200 it will isolate all 4 wires from the source (usually a computer), including outputting it's own +5 volts. Even so, Schiit still just recommends using a good old (i.e, meets spec) USB cable in, and likewise a good old (meets spec) coax cable out.



So your saying no noise can pass though a USB cable because it is filtered, OK as that was why digital was invented.

 Could possibility inaudible noise have been missed because as it is inaudible no manufacturer bothered to filter for it...?

Sorry about so many questions.


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## ev13wt (Oct 20, 2017)

Clive101 said:


> So your saying no noise can pass though a USB cable because it is filtered, OK as that was why digital was invented.
> 
> Could possibility inaudible noise have been missed because as it is inaudible no manufacturer bothered to filter for it...?
> 
> Sorry about so many questions.




Imagine a beach. There are the big sets of waves coming in, plus a huuuge amount of tiny waves all around. Lets call the big waves the audio signal, and all the small waves "noise".
You are a wave creator. You send big waves to the beach. One per 5 seconds. The height of the wave symbolizes the loudness of the signal. Wave, 5 sec pause, wave, 5 sec, 5 sec, wave, wave = 1010011

In analog ocean, your friend the amp counts all waves and makes them bigger. It does not care about noise or signal, it simply amplifies the entire scene. Big waves, small waves, cross waves. Its now a storm!

In a digital ocean, your other friend Mr. dac input counts all the waves coming in, but only looks for 2 things: Is the wave bigger than "x", and is there a space of 5 seconds where no wave comes in?
It converts the information back to "real waves" and shows the amp the perfect ocean, smooth everywhere but for the clearly visible and smooth rollers coming in. Amp is happy, listener is happy.
Wave, 5 sec pause, wave, 5 sec, 5 sec, wave, wave = 1010011

If the other waves, that represent the noise, are as big as the factor X, digital transmission will "fall apart". Otherwise, you always get a perfect beach scene. The noise waves are simply disregarded entirely.

So as long as the usb cable transmits the signal waves at a "higher volume" than the noise waves, the signal is perfectly recontructed by the DAC.

Any noise smaller than the peak of a "1" is simply a non issue. It disappears. Long version: https://en.wikipedia.org/wiki/Entropy_(information_theory)


----------



## Darren G

@Clive101 - For the data lines, the receiver's job is to take those two data lines, detect the high/low state of the lines, and what comes out the other side really is just 1 or 0.  It's worth reading an article or two on the details, but the high/low signals occur at a frequency, and frequencies above/below those don't trigger the 1 or 0 out decision.  What comes out is not music, it's not what you are going to hear either, and you aren't listening to the 1 or 0s.  Later, the DAC converts those 1s and 0s to analog, and that's what you hear, so the answer really is the noise is filtered.

Some people still worry about voodoo noise slipping through, but can't explain how that happens either.  There is something to concerns of ground loops, but the solution to that is isolation (some other outputs, like AES require isolation as part of the spec) or sometimes re-arranging the wall sockets you plug your gear into.   Already commented on the +5V, which some DACs don't use anyway.  There there is that the DAC has a case to shield it, but anyway...

If someone is having issues, spending more on a USB cable isn't going to solve it.  Something like the Schiit Eater actively can address isolation, but the USB cable, I'm in the save my $ camp and spend it on something else.


----------



## Clive101

ev13wt said:


> Imagine a beach. There are the big sets of waves coming in, plus a huuuge amount of tiny waves all around. Lets call the big waves the audio signal, and all the small waves "noise".
> You are a wave creator. You send big waves to the beach. One per 5 seconds. The height of the wave symbolizes the loudness of the signal. Wave, 5 sec pause, wave, 5 sec, 5 sec, wave, wave = 1010011
> 
> In analog ocean, your friend the amp counts all waves and makes them bigger. It does not care about noise or signal, it simply amplifies the entire scene. Big waves, small waves, cross waves. Its now a storm!
> ...



Thank you, yes I get point, thought I was on holiday for one moment..!

Yes aware of that but..... can the inaudible noise go though the USB cable though Mr Dac and somehow affect the SQ when it gets into Mr Amp...?


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## Clive101 (Oct 20, 2017)

Darren G said:


> Some people still worry about voodoo noise slipping through, but can't explain how that happens either



Yes can that be the cause, the voodoo effect, well could the noise travel though the electrical circuits of the Dac..? Sort of by passing the processing, it is all interconnected ..?

If the answer is no I have finished with my questions, but thank you all for your patience I will continue to stay and see what happens ...

Edit @gregorio has answered this in the next post thank you


----------



## gregorio

Clive101 said:


> [1] So your saying no noise can pass though a USB cable because it is filtered, OK as that was why digital was invented.
> 
> Could possibility inaudible noise have been missed because as it is inaudible no manufacturer bothered to filter for it...?
> 
> Sorry about so many questions.



1. No, he's saying no noise (except in very exceptional/rare circumstances) can affect the digital data. Noise can and does affect analogue signal circuits, that's why all DACs have a noise floor.
2. No, manufacturers publish noise specifications for their DACs, signal to noise ratio and dynamic range specs for example. Both of these specs are beyond the limits of audibility and to publish those specs they obviously have to measure them. So inaudible noise is routinely measured and reduced even further, to provide impressive looking specs. Noise floors of DACs today, even relatively cheap ones, are commonly at least 30 times lower than the threshold of audibility and at least 100 times below the noise floor on the recordings themselves.

G


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## ev13wt (Oct 20, 2017)

Clive101 said:


> Thank you, yes I get point, thought I was on holiday for one moment..!
> 
> Yes aware of that but..... can the inaudible noise go though the USB cable though Mr Dac and somehow affect the SQ when it gets into Mr Amp...?



You haven't defined "inaudible noise". Frequency spectrum? Amplitude? Light is inaudible noise, but it doesn't affect the amp.



Yes, if it is present on the recording and the audio is not saved in a lossy compresson of sorts. 

Otherwise, if there are no ground problems, no. (This to your "it is all connected" reference.)


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## gregorio (Oct 20, 2017)

Clive101 said:


> [1] Yes can that be the cause, the voodoo effect, [2] well could the noise travel though the electrical circuits of the Dac..? Sort of by passing the processing, it is all interconnected ..?



1. The voodoo effect is imaginary and we have not yet learned how to pass imagination down a cable, even an audiophile cable! 
2. Noise can and does pass through the electrical, analogue circuits of the DAC, as explained previously. Yes, it is all connected and it's quite complex, which is why circuit designers go to university and study it, but it's all problems which were sorted out years or decades ago and any vaguely competent designer should keep the noise way below audibility.

G


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## Clive101

gregorio said:


> 1. The voodoo effect is imaginary and we have not yet learned how to pass imagination down a cable, even an audiophile cable!
> 2. Noise can and does pass through the electrical, analogue circuits of the DAC, as explained previously. Yes, it is all connected and it's quite complex, which is why circuit designers go to university and study it, but it's all problems which were sorted out years or decades ago and any vaguely competent designer should keep the noise way below audibility.
> 
> G


Thank you.


----------



## Arpiben

Clive101 said:


> Thank you for the reply
> 
> I have particular interest in the in measurable differences of inaudible noise which can pass though the USB cable (if that's possible) and how the design and materials of the USB cable could affect this inaudible noise.



Let me try this way starting with some basics.

A *transmission line, *a pair of wire in our case is nothing more than:






dx: unit length

When dealing with USB certified cables  there are constraints for R/L/G and C. You may change material and it will slightly change thoses values but they must be kept within specifications.
A transmission line is greatly dependant on the load or characteristic impedance at entry  Port A and output Port B. A will be the load from player and B the input load from DAC



 .

USB also provides specifications for transmitters (Port A ) and receivers (Port B)

In order to cancel electromagnetic interferences from* external* sources data is transmitted in differential mode and very often through a twisted cable pair.
The USB receiver will eliminate the EMI by Common Mode Rejection ( CMR cf @pinnahertz posts)
USB20 specifies twisted pairs for Full Speed and High Speed Rates.

*Twisted pairs:* https://en.wikipedia.org/wiki/Twisted_pair

There are different ways to twist the pairs for increasing the noise rejection. Data pairs or even power pairs may be shielded for improving not only EMI but also for reducing their own radiation. Shielding provides an electrically conductive barrier to attenuate electromagnetic waves external to the shield, and provides a conduction path by which induced currents can be circulated and returned to the source, via ground reference connection.
Then again some shields/foils are more efficient when dealing with Low Frequencies some with High Frequency.

Anyhow in normal environment, a compliant USB cable is more than enough for dealing with those external interferences.

Things can become more complicated when facing unproper grounding connections or management at DAC or Source level.
We may add more complexity by adding that* external interferences are not only *entering DAC via its USB cable/receptable or plug parts. In fact all Ins/Outs may act as entry point even your own body when listenning through headphones or touching metallic parts of your listenning chain...
We may still add more complexity by adding that *interferences* may be *internaly* generated inside player or DAC and then cable may carry those noises through ground/power wires.

That is the reason why, we keep saying, that it is not to USB cable to deal with design issues from players or DACs. 

Adding inductance L to USB cables via ferrite chokes or beads in order to reject HF will in most cases reduce the SNR (Signal to Noise Ratio) of the data signal at the risk of having data integrity issues. Hereunder eye patterns examples ( left correct / right not compliant)





With 'specialized' audiophie USB cables, we have not the chance to have access to any measurement: eye patterns at various audio PCM rates for example, EMI rejection,AC rejection, etc....

Hope it helps


----------



## ev13wt

Thank you  very much for the time!

I feel like I understood a lot now, but a new area has opened up with so much more complexity. I love a challenge. Eye diagram. Seen it before, no idea what it actually shows. More googling for papers is in order!


----------



## Arpiben

ev13wt said:


> Thank you  very much for the time!
> 
> I feel like I understood a lot now, but a new area has opened up with so much more complexity. I love a challenge. Eye diagram. Seen it before, no idea what it actually shows. More googling for papers is in order!



Try this application note:
https://dl.cdn-anritsu.com/en-us/te...cation-Notes/Application-Note/11410-00533.pdf


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## bigshot

The important thing that always seems to get overlooked is the just detectable difference threshold for human ears. It's great to talk about noise in cables in theory, but it doesn't mean anything if you can't hear it. And the kinds of noise being discussed here is so far below the threshold of perception it isn't even worth talking about. As long as a cable is designed and manufactured without any glaring errors, it's as good for the purposes of transferring signals representing music as any other cable.

Audiophiles waste most of their energy worrying about things that aren't even an issue. There are much more important things to attend to that actually will improve the sound of their system. And perhaps even more importantly, there are much more elegant ways of arriving at the same place that don't require a bunch of expensive equipment and complete lack of ergonomics.


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## Darren G (Oct 21, 2017)

Two key facts are so well explained above -

1.) The whole point of digital data transfer is to transmit information reliably, while filtering out analog noise on the wire.
2.) ALL electronic gear has a noise floor, and that noise floor is never 0.  This is nothing new, it's well understood, and the goal of most manufacturers is to lower that floor well below the level of what us humans can hear (that is what the word 'inaudible' means).

--

If anyone is still having nervousa about USB, there is the Schiit Eitr, though even then, those who have it write about a 1-2% difference (i.e., minuscule), and not in blind, or double blind testing, 1-2% subjective impressions.  Schiit says up front, USB Nervousa solved (in their usual joking manner).  It checks these nervousa boxes -

USB processing moved outside of the DAC?  Check.
Ground isolation? Check (Coax out to your DAC is transformer coupled).
+5 volt isolation? Check (it doesn't even connect the source +5, and uses it's own linear power-supply).
Do you fret over jitter?  Check (uses 44.1K and 48K on-board crystals to emit a well-clocked SPDIF stream out over coax).

But again, Schiit is good about making no claims you will hear any difference.


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## Leporello

^ Couldn't we also say the that noise is not actively filtered out but - instead - gets filtered out? This is because in the digital world neither the sender nor the receiver can tell the difference between a noisy 1 (or 0) and a clean one.


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## mandrake50

Maybe better than "filtered" is to say it is simply ignored. Noise can be mixed with the signal, but the receiver  does not pay any attention to it. It does not know how.
The only time noise would play a part is if it is so strong that the receiver can no longer discriminate the 0 and 1 transitions.


----------



## Darren G

mandrake50 said:


> Maybe better than "filtered" is to say it is simply ignored. Noise can be mixed with the signal, but the receiver  does not pay any attention to it. It does not know how.
> The only time noise would play a part is if it is so strong that the receiver can no longer discriminate the 0 and 1 transitions.



That was what gregorio wrote.  The exception, yes it's possible, but in real use such noise never happens.  No cable is gonna save anyone if there is such an overload of noise that the receiver cannot differentiate.


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## Clive101

http://madscientist-audio.com/husb.html
http://www.madscientist-audio.com/magictubes.html
Since the thread has stalled, thought I would add these links.


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## Clive101

Hang on guys these are my favourites
http://www.madscientist-audio.com/blackdiscus.html
There is a competition to win a set..!

Some sort of placebo or filtering ..?...!


----------



## Niouke

Clive101 said:


> http://madscientist-audio.com/husb.html
> http://www.madscientist-audio.com/magictubes.html
> Since the thread has stalled, thought I would add these links.



Haha I've started to read the first link, but that's just too much for me 

"The Heretical-USB uses a seperately screened pair that is capable of 10x the USB 2.0 data rate (5Gbits/sec). It also uses some tuning to adjust the characteristics of the cable - it's this tuning that gives 90% of the benefit of this cable."

Good old "more is better" 

I stopped just after this gem:

"A strange thing happened during late testing of the Heretical USB - it became apparent that the 2 meter length sounded better than other lengths. This is not magic; it's due to the capacitance of the cable. 3 meters sounds better than 1 meter but not as good as 2 meters.  So it was decided to make 2 meters the minimum length."

What really?????? Are they building FM radio antennas or USB cables? base price is 200$   there's an email address at the end I'm tempted to just flame them, but they probably already know their product is dog poop.


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## Niouke

why did I click the magic tubes link?


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## Clive101 (Oct 31, 2017)

Niouke said:


> why did I click the magic tubes link?


 I dare you to click on the black discus link..!

http://www.madscientist-audio.com/blackdiscus.html


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## Niouke

Hilarious!! they even admit it's bull yet sell it for 30$


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## bigshot

Looks like someone putting reese's peanut butter cups all over their stereo system.


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## amirm (Oct 31, 2017)

Leporello said:


> ^ Couldn't we also say the that noise is not actively filtered out but - instead - gets filtered out? This is because in the digital world neither the sender nor the receiver can tell the difference between a noisy 1 (or 0) and a clean one.


The receiver that extracts the digital data doesn't care (up to a point).  Question is what happens to that noise with respect to the rest of the DAC.  If allowed to bleed into the DAC reference, clock or analog output, it would show up there.

Fortunately vast majority of DACs -- even the ultra cheap ones -- are immune to this to great extent.  And certainly below threshold of audibility.

There are exceptions such as the horribly designed Schiit Modi where if you cough next door, its output changes.    Using that and Sonore MicroRendu I did a bunch of measurements of USB cables:  Here is an example outcome, comparing the TotalDAC d1 "audiophile" USB cable to generic but long one:











But if you make the generic cable short (yellow), it handily beats the TotalDAC cable (red):





Switching the DAC to Behringer we see that even the long cable does the same thing as TotalDAC:









I did bunch more tests of USB cables including "stub" rigid connectors from likes of Uptone:






Here we see that with sensitive DACs, shorter USB cables is better.  But again with half decent DACs, that doesn't matter either:






I let you read the article for the rest.  Bottom line, if you worry about USB cables, just keep their lengths short.  Better yet, get a DAC that is insensitive to such things which per above, includes vast majority of DACs.


----------



## amirm

Gosh, I can't get all of those measurements to show up correctly no matter what I do.  So please read the articles for the data.


----------



## bigshot

Amirm, does any of that cause audible distortion? It looks to me like every one of those would perform the same for all intents and purposes.


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## amirm

bigshot said:


> Amirm, does any of that cause audible distortion? It looks to me like every one of those would perform the same for all intents and purposes.


Definitely not if you put the Schiit aside.  Even on the Schit it may be hard or impossible to tell.  Then again, there is so much schiit going on there, it is hard to find the music within.  

My reason for posting the data was to show that we can measure it and effects can be there.  They bother the eye but the ear is just fine....


----------



## bigshot

Perhaps I'm reading it wrong. The highest spike in any of those charts appears to be -126dB. I can't imaging that being even close to audible.


----------



## gregorio

bigshot said:


> Perhaps I'm reading it wrong. The highest spike in any of those charts appears to be -126dB. I can't imaging that being even close to audible.



True but the schiit Modi results indicate it's susceptible to noise through the USB cable, get a several meter USB cable and a very noisy source and you could be up into audible territory.

G


----------



## bigshot

He should try testing it with a longer cable and find out. If it comes out below the threshold, it probably doesn’t matter


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## amirm

bigshot said:


> He should try testing it with a longer cable and find out. If it comes out below the threshold, it probably doesn’t matter


I will put it on my TODO list.


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## Arpiben

The AES3 Jitter test signal used in the measurements (12kHz -3dBFS/ 1LSB 250Hz) is not the most appropriate for [DAP+USB cable + DAC+Audio Out cable] system noise characterization when dealing with USB Audio.

With USB (or HDMI) audio content is sent in packets and not as a synchronous continuous stream the J-Test signal can not induce jitter.
Because we can’t stimulate jitter at a particular frequency, unless there is a specific coherent interference source causing it, any jitter that is present may very likely be random and will just cause an increase in the noise floor with no visible spikes in the FFT.

At the end, by switching USB cables in the system you end up measuring differences among: Noise floor variations and spurious/spikes from coherent interference sources . 

Nevertheless if we expand the actual frequency range of observation to 20Hz-20kHz ( not only fs/4 +/- 2kHz) or at the hundred MHz range we should be able to have a better view. The difficulty will always be how to interpret the results.

That said, I agree that the J-Test even if not used in its context allows to detect part of the design flaws.


----------



## mandrake50

@bigshot
Nor, perhaps more important, interfering with the transmission of the digital signal. Even if someone believes that somehow this is passed on through the DAC and into the audio stage (not likely if even possible) it is insignificant.


----------



## amirm

mandrake50 said:


> @bigshot
> Nor, perhaps more important, interfering with the transmission of the digital signal. Even if someone believes that somehow this is passed on through the DAC and into the audio stage (not likely if even possible) it is insignificant.


Actually all of my measurements are through the DAC.  I mentioned the DAC models in my post/links.  I could care less what happens upstream on USB bus.


----------



## amirm

Arpiben said:


> The AES3 Jitter test signal used in the measurements (12kHz -3dBFS/ 1LSB 250Hz) is not the most appropriate for [DAP+USB cable + DAC+Audio Out cable] system noise characterization when dealing with USB Audio.
> 
> With USB (or HDMI) audio content is sent in packets and not as a synchronous continuous stream the J-Test signal can not induce jitter.
> Because we can’t stimulate jitter at a particular frequency, unless there is a specific coherent interference source causing it, any jitter that is present may very likely be random and will just cause an increase in the noise floor with no visible spikes in the FFT.


J-Test actually remains quite relevant in our tests of USB DACs.  It is dither free, high-frequency and toggles all the data bits.  All of this has a way of causing jitter components to become visible far, far more than they would with music.  Imagine the last time you saw near 0 dBFS music content at 12 Khz!  You would go deaf listening to that to say nothing of your tweeter cooking good.    I plan to write a more detailed article on this in a future as there is a lot of confusion in this regard.

As to noise, we actually pay attention to noise floor rising and as a result, the amount of random jitter there. So by your own notion, it works there.

On packetization of USB, that actually shows up nice too at its packet timing if it bleeds into either Vref or Clock signal.



> At the end, by switching USB cables in the system you end up measuring differences among: Noise floor variations and spurious/spikes from coherent interference sources .


Isn't that what the question was?  That there is more than "1s and 0s" here?



> Nevertheless if we expand the actual frequency range of observation to 20Hz-20kHz ( not only fs/4 +/- 2kHz) or at the hundred MHz range we should be able to have a better view. The difficulty will always be how to interpret the results.
> 
> That said, I agree that the J-Test even if not used in its context allows to detect part of the design flaws.


There is no difficulty here: we can't hear the ultrasonics so easy to interpret.    I have done wide-bandwidth measurements at times.    See example of my review of Uptone LPS-1 supercap power source: https://audiosciencereview.com/foru...ar-power-supply-review-and-measurements.1849/







As you see here, there was no reduction of noise as claimed by the manufacturer at higher frequencies higher.

Be careful of frequencies well above this as in Mhz you ask about.  High-speed ADCs running at these speeds have much lower dynamic range than the 24-bit converters in my analyzer.  And at any rate, things like probing matters as otherwise you pick up a bunch of common mode noise you can confuse as DUT output.

Anyway, the key here that J-Test signal was plenty to show differences here.  Indeed this has caused the designers of a number of products to go back to the drawing board and rethink what they had assumed.  In the case of UPtone ISO Regen for example, it showed mains AC leakage due to switchmode supply which has nothing to do with jitter:https://audiosciencereview.com/foru...so-regen-review-and-measurements.1829/page-18


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## bigshot

I really don’t see the point of discussing inaudible things. It just justifies the snake oil.


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## Arpiben

amirm said:


> J-Test actually remains quite relevant in our tests of USB DACs.  It is dither free, high-frequency and toggles all the data bits.  All of this has a way of causing jitter components to become visible far, far more than they would with music.  Imagine the last time you saw near 0 dBFS music content at 12 Khz!  You would go deaf listening to that to say nothing of your tweeter cooking good.    I plan to write a more detailed article on this in a future as there is a lot of confusion in this regard.
> 
> As to noise, we actually pay attention to noise floor rising and as a result, the amount of random jitter there. So by your own notion, it works there.
> 
> ...



Thanks for your detailed answer as well as the measurements provided.
Making it short, I am not arguing about Julian's Dunn J-Test being relevant for DAC' s charcaterization of various jitters: intrinsic/sampling/cable induced/etc...
Dealing with packets remove the 1 LSB/250Hz composant and keep only the fs/4 since it is not inducing any Packet Delay Variation or in other words any data jitter.

Now by swaping USB cables and comparing the different spectrum/FFT you need to assume that your Digital Audio Player used during testing is always sending the data with same PDV and same internal noise. You are also assuming that the EMI/RFI in your testbench area is constant or neglectable It is probably what you are already doing.

Now as an audio layman, I am also wondering like @bigshot and others if all this is audible?
In my short experience, I have been more bothered by AC components than anything else.
Rgds.


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## bigshot (Nov 2, 2017)

I don't understand why someone would say that one DAC is better or worse than another because it measures higher or lower while still being well beyond the threshold of transparency. I judge equipment by its ability to do the job of playing music for human ears. I haven't run across any player or DAC or cable or amp in the past 20 years that doesn't fit the bill on that score. Sound Science people can sometimes be just as prone to focus on stuff that doesn't matter as audiophools. If they enjoy the mental exercise, that's fine. But I sure hope no one takes this stuff into account when they make buying decisions. It's a waste to spend money on things you can't hear. Better to focus on features and usability.


----------



## reginalb

bigshot said:


> ...I haven't run across any player or DAC or cable or amp in the past 20 years that doesn't fit the bill on that score....



You're clearly knowledgeable, and have mentioned in the past that you're pretty careful in your selection of gear. I have definitely run across a couple items that don't fit the bill. I had a Hifiman DAC/amp that was very susceptible to noise, and it got really audible at times even with (quiet) music playing. I had a "Viper" (the company isn't around any more I don't think) amplifier for subwoofers in my car when I was teen (yeah, I was one of those kids) that produced so much distortion it was just awful to listen to. I had to fight with the local car audio store to take a return on the thing. 

Those were the only audio devices that I've owned with clearly audible issues, but I'm just saying, they're out there for sure.


----------



## bigshot (Nov 2, 2017)

They were probably defective from crappy manufacturing. Did you return them for your money back? I sure would. I had a laptop with a defective mother board, it wouldn't even boot up properly. And I bought an amp once that ran for fifteen minutes and made a popping sound and it was dead. Those both got packed back up and exchanged.


----------



## reginalb

bigshot said:


> They were probably defective from crappy manufacturing. Did you return them for your money back? I sure would. I had a laptop with a defective mother board, it wouldn't even boot up properly. And I bought an amp once that ran for fifteen minutes and made a popping sound and it was dead. Those both got packed back up and exchanged.



As I mentioned, the amp for the car I did for sure, but it took a fight with the store. 

I didn't return the Hifiman, it was $20, I think, and I did use it. It was better at home where there were fewer sources of interference than my office. I eventually sold it. 

But I think that at least in the case of the Hifiman, it was a design flaw. Couldn't tell you on the amp.


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## bigshot

I guess you can't expect much for $20.


----------



## amirm

bigshot said:


> I don't understand why someone would say that one DAC is better or worse than another because it measures higher or lower while still being well beyond the threshold of transparency. I judge equipment by its ability to do the job of playing music for human ears. I haven't run across any player or DAC or cable or amp in the past 20 years that doesn't fit the bill on that score. Sound Science people can sometimes be just as prone to focus on stuff that doesn't matter as audiophools. If they enjoy the mental exercise, that's fine. But I sure hope no one takes this stuff into account when they make buying decisions. It's a waste to spend money on things you can't hear. Better to focus on features and usability.


There are good number of reasons why we need to measure and get insight into DACs and make purchase decisions based on that:

1. Measurements are repeatable and reliable.  This is far cry from someone saying this and DAC sound the same.  How would I verify that?

2. Our goal should be for a DAC that is transparent for all people and all content.  Again having someone test a few samples of music and their ears alone is not sufficient.

3. Where possible we need to reward best in class engineering as opposed to sloppy ones.  Yes, this is a philosophy but there are thousands of DACs in the market these days.  Many are put together by incompetent designers.  We need to weed them out and give our money to those that know what they are doing.  Why reward bad work?  Would you buy a car that has some paint chips on it just because it drives the same as other that doesn't at the same price?

4. I have examples of DACs with audible problems: Schiit BiFrost.  

5. For any technology, it is good to have a margin of safety.  Well designed equipment goes beyond mere threshold of detection for distortion.

6. I have tested a ton of digital products in the last year in ASR Forum and there are some real dogs there that are only identified when we measure them.  I like to see us avoid these products even if in casual listening we can't hear such problems.  Why throw good money after bad?

7. We need to check our assumptions.  Far too often as objectivists we throw our weight around that such as can't possibly be measureable or audible.  Well, it is good to have data behind the former.  My experience is that in many cases our dogma is incorrect.  Take the example of USB cables making a measureable difference.  As a group, we need to have data behind our conclusions than just saying, this and that is the same.

8. Another point is learning.  By measuring and looking at the data, we learn more about our audio systems and can figure out how to better test them audibly.  How would we know what type of music to use for audibility test if we lack such data?

So while in summary I agree that if two products are truly the same audibly, we should buy either one, that doesn't translate into real world where we can't really ascertain that in a reliable manner.


----------



## bigshot (Nov 2, 2017)

I only want a unit that works and is transparent. If it's 2X transparent or 5X transparent it makes absolutely no difference to me. I wouldn't label something a dog unless it had audible noise. I've never run across anything that does. When I get a new piece of equipment, I rack it up against other stuff I have and make sure it sounds the same. That works fine for my purposes, and I don't see much point spending a lot of money for something that sounds exactly the same to me, Honestly, I think features and user interface are much more important for most players. I don't have any need for an external DAC though. My phone and computer have great sound built in.

By the way, what aspect of the Schiit BiFrost should I be looking at for audible noise? I've found a couple of tests of it and offhand I don't see anything that looks audible. I don't know why it doesn't upsample though. Most everything does now. Is this some sort of DAC aimed at misguided purists or something?


----------



## amirm

bigshot said:


> I only want a unit that works and is transparent. If it's 2X transparent or 5X transparent it makes absolutely no difference to me. I wouldn't label something a dog unless it had audible noise.


I just reviewed the $30 Behringer UCA220.  Here is its output performance when feeding it 24-bit, -90 db sine wave as compared to Behringer UMC204HD ($79):







Red/yellow is the UMC204 HD which shows a clearly defined sine wave.  The blue+green that is jumping all over the place is the UC222.  Would you go for the UC222 regardless knowing that it can't even reproduce 16 bits cleanly?


----------



## bigshot (Nov 2, 2017)

What about sine waves up where I can hear them- like say -40dB? I really don't think I can hear anything at -90dB in music. If I put on my CD of Beethoven's 9th and played it fairly loud, how would it sound compared to any other DAC? It would be nice to have it be clean to the edge of Redbook, but for Behringer and for 30 bucks, I don't know if I would even expect that.


----------



## amirm

bigshot said:


> What about sine waves up where I can hear them- like say -40dB?


-40 db?  Your ears have 106 db SPL dynamic range.   If you start at -40, you would be throwing a good chunk of that away.

I can hear -90 db sine wave using headphones without problems.  It is the last couple of bits of 16 bit audio.  If you want to throw away that much performance, you and I can't be friends!  

I think you said you produce music?  If so, go and create the -90 db tone and see if you really can't hear it.

Regardless, if people deliver 16 bits of music to you on CD, explain to me why you think you shouldn't get something that produces all of that.


----------



## gregorio

amirm said:


> Regardless, if people deliver 16 bits of music to you on CD, explain to me why you think you shouldn't get something that produces all of that.



Do people deliver 16 bits of music to you? AFAIK, there are exceedingly few recordings with more than about 60dB of dynamic range, so people deliver about 10 or so bits of music to you. Nevertheless, I agree that we should be looking for DACs which can easily achieve at least 90dB of dynamic range, noise no higher than -100dB, just to be safe.



amirm said:


> 1. Measurements are repeatable and reliable.  This is far cry from someone saying this and DAC sound the same.  How would I verify that?
> 3. Where possible we need to reward best in class engineering as opposed to sloppy ones.



1. There are very few here and none of the regulars, who would disagree with the notion of taking/using accurate measurements.
3. This is where things get a bit murky for me. A decent, fairly inexpensive DAC might achieve say -120dB of jitter noise, while a relatively expensive, best in class model may reduce that significantly, down to say -140dB or even lower. At any vaguely sensible playback level we're never going to hear the jitter noise with the inexpensive model. What is the point then of the expensive model? In this case, isn't "best in class" essentially just a marketing exercise; Impressive looking numbers on paper which don't even affect what comes out of the speakers/headphones, let alone are audible, numbers which essentially exist for no tangible benefit other than to help justify it's higher price? Should we be rewarding or condemning that "best in class"?

G


----------



## castleofargh

amirm said:


> -40 db?  Your ears have 106 db SPL dynamic range.   If you start at -40, you would be throwing a good chunk of that away.
> 
> I can hear -90 db sine wave using headphones without problems.  It is the last couple of bits of 16 bit audio.  If you want to throw away that much performance, you and I can't be friends!
> 
> ...


that's way too misleading. even if I set my output to 106dB which I personally never do to listen to headphones, this would get me a 16dB SPL test tone. so sure that can be audible, standing quietly below the noise floor of my room that's about twice as loud. but of course this has nothing to do with instantaneous dynamic range, because even with quiet music at the same time I would likely lose the tone from masking, and with anything coming close 70 or 80dB SPL(whatever my own trigger level is), the Stapedius(called that way from latin expression "music what are u doin? music stap!") would reduce the sensitivity of the ear, which would likely stop me from hearing anything anymore at 16dB SPL.

I'm not saying it's wrong or useless to measure -90dB, but hearing those levels in music playback is not IMO why those measurements are relevant.


----------



## ev13wt

I can't even hear the darn 70dB door bell when I'm jamming out


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## bigshot (Nov 3, 2017)

amirm said:


> -40 db?  Your ears have 106 db SPL dynamic range.   If you start at -40, you would be throwing a good chunk of that away.



Human ears can only hear about 40dB of dynamic range at a time. If you play loud music for a few minutes, then someone tries to whisper to you, you aren't going to hear it. Give yourself a few minutes in a quiet room and your ears will acclimate and you will be able to hear quieter things. But a sound back up in the loud range will make you jump out of your chair.

It's fine to say "I paid for 16 bit and I want all of it dammit!" but the fact is that most music averages a dynamic range of 40dB and even the most dynamic music doesn't get higher than 55 or 60dB. Down at -90dB on a CD,assuming a super clean DAC and recording, all you will hear is the air conditioning running in the recording booth and ambient room tone.

The problem with numbers is that it is very easy to get seduced into the "bigger numbers are always better" fallacy. We don't listen to numbers. And we don't listen to sine waves. We listen to music, and ultimately that's the context we should be focusing on.

I do agree that a DAC should perform to Redbook spec. But every reasonably competent DAC does that. Pointing to a single $20 or $30 DAC with bad specs well below the range where it really makes any difference in practical application isn't proving the point that we need to be very careful to thoroughly test DACs in general. The truth is, you have to really dig to find a DAC that doesn't perform up to 16/44.1 standards. Finding one with audible noise at normal listening levels is virtually impossible. And no, you can't hear a -90dB sine wave at a normal listening level. You only can hear it if you crank the volume or adjust your ears to near silence. For the purposes of listening to music, a -70dB noise floor is perfectly adequate. It might offend sensibilities and create OCD anxiety in some audiophiles, but the music will still sound fine at a normal listening level.


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## castleofargh

the Adel papers were referring to about 60dB, then the ear reduces its sensitivity when reaching a trigger level, giving a global range beyond 100dB but with only one setting available at a time. low gain/high gain each providing about 60dB at once.


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## amirm

bigshot said:


> Human ears can only hear about 40dB of dynamic range at a time. If you play loud music for a few minutes, then someone tries to whisper to you, you aren't going to hear it. Give yourself a few minutes in a quiet room and your ears will acclimate and you will be able to hear quieter things. But a sound back up in the loud range will make you jump out of your chair.


At this rate, if this were food, you would be convincing yourself that you could live on 100 calories.  

No, it doesn't work that way.  I can be listening to music that has momentary peaks to -30 db and decay down.  I don't go deaf listening to 10 msec of that peak.  It is a silly objectivists argument to talk about loudness that way.  We are not listening to pure tones at 100+ db.  We are listening to music that can have peaks above that.  But since TTS and hearing damage are functions of time, none of that becomes a concern here.  And when listening to quiet passages, you don't need the help of OHC to change the dynamic range.

Ultimately you have to decide who you are.  Are you the one that washes his hands every time you leave the bathroom or every other time?  Or every fourth time?  Because after all, no one can prove that you can get sick if you didn't wash your hand every time.

As an engineer, I aspire to see excellence in designs that my peers in the industry put out.  I don't want to see people who have spent thousands if not tens of thousands of dollars on music content, buy non-performant products based on word arguments.  We can find the good and separate it from bad.  And make sure that we have a reproduction system that is transparent for all people and all content.  You personally can deviate from this but it is not a credible argument to sell to others.

The total dynamic range that need to aspire to produce is about 120 db.  That is what it takes to have a totally transparent system.  For reasons why, see this article I wrote for WSR magazine: https://audiosciencereview.com/forum/index.php?threads/dynamic-range-how-quiet-is-quiet.14/

Anything else would require putting limitations on content, person, room, etc. which I am not about to do in order to advance the cause of objectivity.


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## amirm

castleofargh said:


> hat's way too misleading. even if I set my output to 106dB which I personally never do to listen to headphones, this would get me a 16dB SPL test tone. so sure that can be audible, standing quietly below the noise floor of my room that's about twice as loud. but of course this has nothing to do with instantaneous dynamic range, because even with quiet music at the same time I would likely lose the tone from masking, and with anything coming close 70 or 80dB SPL(whatever my own trigger level is), the Stapedius(called that way from latin expression "music what are u doin? music stap!") would reduce the sensitivity of the ear, which would likely stop me from hearing anything anymore at 16dB SPL.


Please read my article that I just post.  You cannot use single number SPL values like that.  You need to a spectrum analysis.  Much of the room noise comes at low frequencies where our hearing is insensitive but a dumb meter is not.  The test tone in question was at 1 Khz.  Sitting in my living room with AC and fridge running, I have no trouble hearing -90 dbSP tone that I used in that measurement using either my Etymotic IEM ER4SR or my cheap over the ear Sennheiser conferencing headset.  And this is with my laptop headphone output and not any kind of external amplifier.  Yet an SPL meter will likely show 50+ db of noise making you think it swamps the tone when it cannot.

There are also advanced psychoacoustics here in how we can hear directional tones (i.e. what comes out speaker/headphones) over diffused noise all around us.

And no masking is no help at all unless you put restrictions on what I listen to.  An acoustic guitar pick decay has nothing to mask that reverb trail.

These arguments go back to putting assumptions and restrictions on content and people again.  That is not the proper way to look at this.  The goal again should be to achieve transparency for even the most critical listener.  Otherwise your advice is not generic enough to apply to everyone who comes here.  Settle for less than excellence if you want.  Just don't tell me about it.    It doesn't cost a lot of money to get there and we as people dedicated to the hobby need to go after it with data, not assumptions.


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## amirm

bigshot said:


> It's fine to say "I paid for 16 bit and I want all of it dammit!" but the fact is that most music averages a dynamic range of 40dB and even the most dynamic music doesn't get higher than 55 or 60dB. Down at -90dB on a CD,assuming a super clean DAC and recording, all you will hear is the air conditioning running in the recording booth and ambient room tone.


Most?  How do you know what most of my music looks like?  What if that is true but I listen to the rest of such music?  I am supposed to solly the low order bits on them for what reason again?

On the air conditioning, again see my article and remember we are talking headphones here.


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## bigshot (Nov 3, 2017)

amirm said:


> I can be listening to music that has momentary peaks to -30 db and decay down.  I don't go deaf listening to 10 msec of that peak.



I wasn't talking about damaging your hearing I was talking about perception of sound. You can't hear really loud or really quiet at the same time. The ears need time to acclimate to a particular range. That range corresponds to the comfortable dynamic range of music- average of 40dB, maximum 55 to 60dB. If the music is loud, the quiet stuff below that range fades away into the background. If the music is soft, loud peaks above that range blast and aren't clear.

If you're recording, by all means use higher data rates and use the best equipment you can. But for listening to music in the home, the standard is different. Apples and oranges. For listening to music in the home, the human ear is the final technical limitation, and better specs beyond the point of audible transparency is overkill. The listener is hearing everything through human ears at a fixed listening level in a real living room with a real living room's noise floor. 16/44.1 is well beyond what is absolutely necessary for good sound.

By the way, when I referred to air conditioning, I was talking about the recording studio. The best recording studio in the world has a noise floor higher than Redbook. You'd have to record in Carlsbad Caverns to get that kind of range.


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## amirm

bigshot said:


> By the way, when I referred to air conditioning, I was talking about the recording studio. The best recording studio in the world has a noise floor higher than Redbook. You'd have to record in Carlsbad Caverns to get that kind of range.


That's also covered in my article.  Did you read it?  Noise is not the same as tones.  And SPL numbers are useless in this type of analysis as it is devoid of psychoacoustics.

And CD is not sufficient unless noise shaping is used and that is not remotely a guarantee in produced music.

Regardless, CD is yesterday's story.  There is no reason whatsoever we should comply with its specifications when we are downloading or streaming digital content.


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## castleofargh (Nov 4, 2017)

amirm said:


> Please read my article that I just post.  You cannot use single number SPL values like that.  You need to a spectrum analysis.  Much of the room noise comes at low frequencies where our hearing is insensitive but a dumb meter is not.  The test tone in question was at 1 Khz.  Sitting in my living room with AC and fridge running, I have no trouble hearing -90 dbSP tone that I used in that measurement using either my Etymotic IEM ER4SR or my cheap over the ear Sennheiser conferencing headset.  And this is with my laptop headphone output and not any kind of external amplifier.  Yet an SPL meter will likely show 50+ db of noise making you think it swamps the tone when it cannot.
> 
> There are also advanced psychoacoustics here in how we can hear directional tones (i.e. what comes out speaker/headphones) over diffused noise all around us.
> 
> ...


 you're the one who threw that 106dB of dynamic up in the air. so we agree on not using a single number like that .
I wasn't trying to reinvent humans, or reject the idea that music could have entire quiet passages where low levels are the music. or even that a single tone alone in a quiet environment could be heard. I only reacted to that number because I was already imagining someone reading that and going "see! 16bit isn't enough for music, I always knew it!". or other mental shortcuts of the same sort.

by chance I've spent last week playing with my new fake(but cheap!!!) IEC711 pretend compliant coupler, calibrating and testing stuff in REW using the ER4SR as double check(with the sensi at 0.2V @1khz on the certificate). so 1khz -90dB with er4sr was the freshest and most concrete reference you could have used on me.  ^_^


edited to remove quintuple negative.


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## bigshot (Nov 3, 2017)

Your article totally confused me with the opening paragraph where you gave figures for typical theater room noise floors that are incredibly high and then subtracted from 24 bit. That makes no sense to me at all. I'm three blocks from a busy freeway and have a 100TB disk array in the back of my theater, but my SPL meter doesn't quite reach 40dB. I generally raise my volume level to overcome that. So with a normal listening level of around 80dB, I'm using about 40dB of dynamic range below normalized peak level, which is a comfortable balance for most things. It flat out isn't possible for me to listen to anything that peaks over 100 or so without flinching, so that tops out my potential dynamic range at about 60dB, which is as much as any recorded music is going to have. Redbook covers all this with dynamic range to spare--- even without anti-aliasing!

As for the technical stuff further down, I'm totally aware of the Fletcher Munson curve and I know I'm talking about approximate values. It certainly does vary depending on the frequency band. Not just because of the FM curve, but also because recorded music varies so much in timbre. So figure my ballpark spits in the wind are +/-10dB. That's fine with me. That still doesn't fundamentally change what I'm saying. I don't think you need to over complicate it. There's a place for ballpark generalizations too. They aren't wrong... they just don't necessarily cover the uncommon extreme examples. It's like the thing we were discussing about DACs. I asked you to tell me about one that had audible noise, and you cited a -90dB spec on a $20 DAC... If you have to go to those extreme ends to find an example, it really doesn't even merit mentioning, because 99.99% of the DACs out there probably fall into anyone's definition of audible transparency for the purposes of listening to music in the home at reasonable listening levels.

It's great if you're interested in all this stuff and you get pleasure from thinking about stuff at this level of detail. Lord knows there are many audiophiles and Sound Science denizens just like you. Maybe knowing all about this stuff gets you the hot chicks. I don't know. But if you're going to try to give people information that you intend them to use as advice for purchasing home stereo equipment, you need to consider the context that they'll be using the equipment in. You certainly better consider the way they are going to be using the stuff if you want to tell people that they are flat out wrong for saying it doesn't matter to them. Real people listen to regular music in their typical homes. They don't require the same specs that an engineer in a recording studio might need. No one expects them to. When I supervise mixes, I try to strike a happy medium that sounds clear and alive in the studio, and will work fine on as wide a range of home equipment as possible. I never assume that the sound I am hearing in the studio is the only "correct" sound... it's just the baseline sound. People are free to buy headphones that sound however they want and EQ their speakers to sound warm or super sharp and clear or emphasized bass and treble with attenuated mids, or whatever they like. I've given them the baseline that makes it more consistent from album to album, so they can set their preferred coloration once and not have to do it for each and every album separately.

There is a fixed baseline, but it isn't carved in stone. It's just the starting point. Each individual needs to adjust for their own particular ears, their own particular transducers and their own particular room. When you get too dogmatic and absolute about that, then people start to ignore you, as well they should. Because if you don't pay attention to the context of their particular listening situation, why should they pay attention to your advice? I don't understand why so many people on audiophile sites don't understand that. I guess the hobby tends to appeal to people who like to force their own choices and preferences on everyone else. Or maybe it's some specific form of OCD. Who knows?

In any case, for all practical purposes in the context of a typical home stereo, 16 bit audio is already into the range of overkill for dynamic range. Sometimes it's best to just cut to the chase and say that flat out. I'll say it for sampling rate/frequency response and distortion too, even timing error. If you are just listening to recorded music a CD is perfect sound to human ears. High bitrate lossy is just as good in many cases. If someone doesn't believe that, they can just set up a listening test for themselves or watch Ethan Winer's seminars in my sig and download his audio samples and they'll know for themselves. I've done all that and that's how I know where the thresholds are. Everyone should take the time to do that, because then they would know what 18kHz sounds like (or doesn't sound like as the case may be), and they'd know what noise at -90dB sounds like (or doesn't sound like) under music. You gotta know what those numbers represent if you want to interpret numbers.


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## Don Hills

The masking demonstration that clinched it for me was the music with the sousa band mixed in at about a -60 db level. (Anyone have the link? I can't find mine.)


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## gregorio

amirm said:


> The total dynamic range that need to aspire to produce is about 120 db. That is what it takes to have a totally transparent system. For reasons why, see this article I wrote for WSR magazine: https://audiosciencereview.com/forum/index.php?threads/dynamic-range-how-quiet-is-quiet.14/
> Anything else would require putting limitations on content, person, room, etc. which I am not about to do in order to advance the cause of objectivity.



I'm sorry amirm but your theory is very flawed. If you are going to talk about "real life" issues, such as noise floors and equal loudness contours for example, then you obviously have to consider ALL the pertinent factors of "real life", not just one of them ... and this is where your article fails! Your article mixes real life with non-real life and completely omits other, far more crucial real life factors. For example:

1. There are roughly 120,000 cinema screens in the world and it's unlikely that more than a faction of 1% of them achieve a noise floor as low as Skywalker Sound.
2. Even if the cinemas did all achieve such low noise floor levels it would be irrelevant anyway! Stick several hundred living, breathing, moving audience members in there and such low noise floor levels are blown out of the water and, not just in terms of amplitude but spectrum as well. Clothes rustling and breathing noise occupies more of the critical hearing band than the very low freq band. Obviously, this applies to music as well, stick 90 living, breathing members of an orchestra, all operating mechanical instruments in an extremely quiet room and it is no longer an extremely quiet room! 
3. Extremely high real life SPLs and SNRs only occur in the case of very close mic'ing which is virtually never used in isolation. The exceptions to this would be the recording of popular music genres and Foley but the result is unacceptable dynamic ranges and unrealistic transients which require taming and shaping, with compression for example.
4. You've used the example of film quite a lot but you've omitted the fact that in film we spend a great deal of time creating and manipulating the film's noise floor. Every real life room (with the exception of some specifically constructed spaces) has an audible noise floor and not just an audible noise floor but a subtly changing noise floor. The vast majority of the time we are consciously unaware of this but in film we run into the problem of picture editing; even within a single scene (in the same location) we've got various shots, angles and takes filmed at different times and when edited/cut together those gradual changes in the noise floor become sudden changes and are very noticeable. In addition, we want this noise floor (called room tone in film terminology) to be audible, although typically only at a subconscious level. If it were not audible, if it were below the noise floor of the cinema, then it would be the room tone of the cinema the audience would hear, not the room tone of the location in the film!
5. Considered together; the noise floor of say Skywalker Sound, the noise floor of a cinema with an audience present and the requirement for the noise floor/room tone of the film to be audible, we have an obvious problem. Even a very low level room tone would exceed the noise floor of Skywalker Sound and be audible but play that mix in a "real life" cinema with it's higher noise floor, plus an audience present (and therefore a much higher noise floor still) and our film's room tones are completely gone, utterly buried. There was a suggested solution, one which I believe was tried, of pumping constant noise through the mix stage speakers to generate a much higher noise floor and thereby create the conditions to more accurately judge the level at which to mix the room tones. However, in practice this solution didn't really work and I don't believe any mix stage actually does this. Room tone levels are essentially a judgement call by the re-recording engineers based on an experienced guesstimate of what "real life" cinema noise floors are likely to be, rather than on the much lower noise floor in the mix stage ...
6. Continuing on from point 5; ultimately, we are talking about the actual content being created/mixed by sound engineers using their judgement and as those engineers are of course human their judgement is obviously based on the human equal loudness curves. So the equal loudness curves are effectively already baked into what ever commercial audio content you're listening to.
7. In real life, as the perceived noise floor decreases so do the average and peak levels which are found to be comfortable.

I've no objection to you using "real life" but then you can't just cherry pick aspects of real life. When the above real life practicalities and aesthetic requirements are considered, then 16bit as a final distribution format is more than enough. Again, in real life, how many music recordings or films do you know which have more than 60dB dynamic range? 100dB of dynamic range is already beyond requirements but even if we accept your figure of 120dB, your measurements of relatively cheap DACs indicate they mostly achieve noise artefacts at or below -120dB and your "best in class" to around -140dB or lower, what real life benefit is that extra 20dB, even assuming it could be reproduced by the transducers in the first place?

G


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## amirm

gregorio said:


> I'm sorry amirm but your theory is very flawed. If you are going to talk about "real life" issues, such as noise floors and equal loudness contours for example, then you obviously have to consider ALL the pertinent factors of "real life", not just one of them ... and this is where your article fails! Your article mixes real life with non-real life and completely omits other, far more crucial real life factors. For example:


There is no need to be sorry.    You just have to read the full article and especially the footnotes:

*References*
_“Noise: Methods for Estimating Detectability and Threshold, ” _Stuart, J. Robert, JAES Volume 42 Issue 3 pp. 124-140; March 1994
_“Dynamic-Range Issues in the Modern Digital Audio Environment, ” _Fielder, Louis D., JAES Volume 43 Issue 5 pp. 322-339; May 1995

Everything in the article is based on those two, peer reviewed, Journal of Audio Engineering Society.  And the authors are luminaries there.  Fielder for example was the president of Audio Engineering Society and more: http://www.aes.org/events/140/presenters/?ID=4649

So when you come back to reply to my post here, please bring big guns with you like this.    Here is the abstract of the paper referenced.  The whole Fielder paper is very worthwhile to read and that is where the bulk of the data in my article came from:







Here is the message that both you may be missing although I have said it repeatedly:

*The goal for a transmission channel must be transparency for all content, and all people.*​
To figure how to achieve that, we need to determine the best that we could produce, and the best reproduction we can create.  That is what Fielder does.  He doesn't just assume things.  He measures rooms and uses psychoacoustically aware data to determine audibility.  Once there, he arrives at the numbers above which again, without noise shaping is not possible with 16 bit format.

It is actually worse in this example as bigshot is advocating something even less than 16 bits by saying nonlinearities and noise in the rightmost bits of 16 bit samples doesn't matter.  In essence he is advocating something like 14 to 15 bits which is way, way, way short of the above research.  Worst yet (for him) we are in a headphone centric forum where a lot of arguments about room noise, etc. fall by the wayside anyway.  

This all gets us back to question he has of "why do you measure and like better performing DACs."  Well, my goal is to see if we can achieve the above criteria because once we do, we are golden.  We as technologies can make a promise to consumers that is backed by data, psychoacoustics and objective measurements.  Then it is a durable and reliable argument.  Without it it is farce and I won't get behind it.


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## amirm

bigshot said:


> In any case, for all practical purposes in the context of a typical home stereo, 16 bit audio is already into the range of overkill for dynamic range.


That is an opinion that you can hold for yourself and your own use.  When you put it forward for the rest of us, then it becomes a problem.  Using psychoacoustics alone we can determine 16 bit with flat dither is insufficient for transparency.  Here is professor Vanderkooy (one of our other audio luminaries) saying the same thing in his published AES paper:  

_A Digital-Domain Listening Test for High-Resolution _
John Vanderkooy
Department of Physics and Astronomy, University of Waterloo, Waterloo, Ontario, Canada N2L 3G1





And this bit which correctly states that if we are going to use noise shaping, it would be better to have higher sampling rates as to have more room in the ultrasonics to stuff the pushed out noise:





And it was exactly what he mentions that allowed me to pass Archimago's test of 24 bit vs 16 in double blind listening test:

foo_abx 1.3.4 report
foobar2000 v1.3.2
2014/08/02 13:52:46

File A: C:\Users\Amir\Music\Archimago\24-bit Audio Test (Hi-Res 24-96, FLAC, 2014)\01 - Sample A - Bozza - La Voie Triomphale.flac
File B: C:\Users\Amir\Music\Archimago\24-bit Audio Test (Hi-Res 24-96, FLAC, 2014)\02 - Sample B - Bozza - La Voie Triomphale.flac

13:52:46 : Test started.
13:54:02 : 01/01 50.0%
13:54:11 : 01/02 75.0%
13:54:57 : 02/03 50.0%
13:55:08 : 03/04 31.3%
13:55:15 : 04/05 18.8%
13:55:24 : 05/06 10.9%
13:55:32 : 06/07 6.3%
13:55:38 : 07/08 3.5%
13:55:48 : 08/09 2.0%
13:56:02 : 09/10 1.1%
13:56:08 : 10/11 0.6%
13:56:28 : 11/12 0.3%
13:56:37 : 12/13 0.2%
13:56:49 : 13/14 0.1%
13:56:58 : 14/15 0.0%
13:57:05 : Test finished.

---------- 
*Total: 14/15 (0.0%) *​
But remember this: you are not advocating 16 bits.  If you did then you would have gone along with my data that showed one DAC could not reproduce the low order bits of 16 bit sine wave.  You are advocating for 14 to 15 bits.  No one that I know in research or psychoacoustics would stand behind that argument for transparency.  For general public music consumption, sure.  But not in the context here.

So no, I can't get behind buying crappy engineered products.  I measure because it matters.  It matters whether a DAC can pass 16 bits cleanly.  If it can't, I have no use for it.  Period.  I am not there to advocate mediocrity and incompetent design.


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## gregorio

amirm said:


> *The goal for a transmission channel must be transparency for all content, and all people.*



That's the difference! You and the papers you quote are talking about all people and all content, whereas I'm only talking about all people and all commercial content; all commercial music releases, all Radio, all TV and all films. You quote real life but in real life what audio content other than commercial music releases, radio, TV and films are people listening to?

G


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## bigshot (Nov 4, 2017)

amirm said:


> That is an opinion that you can hold for yourself and your own use.  When you put it forward for the rest of us, then it becomes a problem.  Using psychoacoustics alone we can determine 16 bit with flat dither is insufficient for transparency.



The things you're talking about are exactly why Redbook is overkill. When you start thinking in terms of absolute extremes, like "How would this stereo system perform at the bottom of Carlsbad Caverns if no one was there to hear it?", then you start getting absolute statements like "120dB is necessary to make the breaths of the orchestra members audible before they strike the first chord."

For some reason, absolutists always seem to be the ones reviewing and discussing audio equipment on line. They think that because they focus on the details that it makes them a better reviewer. But focusing on the tiny details isn't the job of a reviewer. The job of a reviewer is to give someone a clear idea of how a piece of equipment would perform for them if they went out and bought it and set it up in their home and listened to their own music on it. To be good at conveying that, you need to focus on real world issues, not how well a pair of headphones would sound if you were floating in deep space.

There are two areas that I find are sorely neglected in discussion of sound science... one is the thresholds of human perception. Most audiophiles know a lot more about how dithering and timing error and theoretical sine waves work than they do how their own ears perceive sound. They wave perception away saying, "Everyone is different. so It isn't worth discussing." Then they dive right back into discussing things that are dead to rights inaudible again!

The other thing that is neglected is the definition of what those numbers mean in real world sound. How loud is 30dB compared to 120dB? What does 6kHz sound like as opposed to 17kHz? What does 1% THD sound like compared to .005%? What is a nanosecond compared to a microsecond and how do they relate to the hearing of music? Everyone spends hours and hours memorizing numbers and reading scientists' recommendations about how many dB of dynamic range is required. But they don't spend a second figuring out that 120dB is the threshold of pain! Why does anyone need their stereo system to resolve more than 30dB below the noise floor of their listening room and all the way up until their ears ache? That isn't "crossing every T and dotting every I". It's just plain overkill.

You can tell me that some scientist tells me I need 120dB of dynamic range and list all of his credentials, but I'm still going to know that's way beyond the line of overkill. Why do I know that? Because I've taken the time to find out how our ears hear, and I know what the numbers you're talking about represent in real world sound. I don't need sound I can't possibly hear.

Every hobby attracts people with a specific mental pattern I guess. Audiophile sound seems to attract a wide range of neurosis from OCD to paranoia. Nothing is ever good enough. They always take the status quo and push to make it 20% better, even if it doesn't make any audible difference at all. Not all of us are afflicted with that. Maybe those of us who are free of it just recognize it better when we see it.


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## ev13wt

amirm said:


> That is an opinion that you can hold for yourself and your own use.  When you put it forward for the rest of us, then it becomes a problem.  Using psychoacoustics alone we can determine 16 bit with flat dither is insufficient for transparency.  Here is professor Vanderkooy (one of our other audio luminaries) saying the same thing in his published AES paper:
> 
> _A Digital-Domain Listening Test for High-Resolution _
> John Vanderkooy
> ...




You could include your hash for credibility, ya know?


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## amirm (Nov 4, 2017)

ev13wt said:


> You could include your hash for credibility, ya know?


Thanks for the softball   Here you go: https://www.audiosciencereview.com/forum/index.php?threads/a-bit-about-your-host.1906/

Please pay special attention to #7 in the list of my skills.  

Also please see the double blind test I passed in what you quoted from me in test of 16 bits vs 24.


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## mandrake50

Did I miss something. The files listed were both 24/96 ???


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## bigshot

OOoo! I like the title "Chief Fun Officer". At work my door reads "Director of Joy".


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## amirm

mandrake50 said:


> Did I miss something. The files listed were both 24/96 ???


Yes, it is actually quite a clever test with countermeasures against electronic analysis.  If he provided one file at 16/96 and another at 24/96, you could look at that metadata and immediately know which is which.

So what he did was that he first reduced the bit depth to 16 but then converted back to 24.   This way you cannot look at the file properties and tell which is which.  They are both in "24" bit format but one has 16 bits worth of real data and the other (ostensibly) 24.

He actually goes beyond this with other measures to thwart computer analysis: http://archimago.blogspot.ca/2014/06/24-bit-vs-16-bit-audio-test-part-i.html

Due to the fact that this is an "open" test released on the Internet (rather than a listening test in a lab situation where variables could be easily controlled), some measures were implemented to prevent easy differentiation of 24 vs. 16 bit-depth by other means than just listening. (Thanks to _Wombat_ for giving me some ideas.)

1. Files 2, 4 and 6 (Sample B of each track) had 1 ms cut off from the start and files 1, 3, and 5 (Sample A) had 1 ms truncated from the end. This maintains the exact duration of Sample A and B but shifted them temporally. Doing this confounded simple null tests that did not take into consideration the slight timing offset.

2. A very low level -140dB (average RMS power) white noise was mixed into the 16-bit dithered samples (remember, they were placed in 24-bit containers) to affect the LSB so that a simple program that just checked the bit-depth (by looking for "0" in the least significant bits) will think that this is an actual 24-bit resolution file. This small amount of white noise would be _inaudible _and well below the dithered 16-bit audio noise floor (and below the objective noise floor of actual DACs).

3. FLAC was consistently LESS EFFICIENT at compressing the dithered (effective 16-bit) files resulting in _larger _file sizes. As a result, one of the 24-bit files was purposely compressed at FLAC level 2 (versus level 8) to make the file size slightly larger than the respective dithered version.​
"Wombat" is a signal processing guy on HA forum.

Without these measures it is easy to pollute the results the way he is running the test, i.e. people just voting rather than providing "foobar" ABX test results as I have.

I think the files are still there.  If so, I encourage people to run them and see if they can hear the difference.  It is not an easy challenge by any means.


----------



## amirm

Here is another set of public tests you can try to run of 16/44.1 against high-res: http://www.avsforum.com/forum/91-au...-aix-high-resolution-audio-test-take-2-a.html

And my results:

foo_abx 1.3.4 report
foobar2000 v1.3.2
2014/07/10 18:50:44

File A: C:\Users\Amir\Music\AIX AVS Test files\On_The_Street_Where_You_Live_A2.wav
File B: C:\Users\Amir\Music\AIX AVS Test files\On_The_Street_Where_You_Live_B2.wav

18:50:44 : Test started.
18:51:25 : 00/01 100.0%
18:51:38 : 01/02 75.0%
18:51:47 : 02/03 50.0%
18:51:55 : 03/04 31.3%
18:52:05 : 04/05 18.8%
18:52:21 : 05/06 10.9%
18:52:32 : 06/07 6.3%
18:52:43 : 07/08 3.5%
18:52:59 : 08/09 2.0%
18:53:10 : 09/10 1.1%
18:53:19 : 10/11 0.6%
18:53:23 : Test finished.

---------- 
*Total: 10/11 (0.6%)*
*
---
*
foo_abx 1.3.4 report
foobar2000 v1.3.2
2014/07/10 21:01:16

File A: C:\Users\Amir\Music\AIX AVS Test files\Just_My_Imagination_A2.wav
File B: C:\Users\Amir\Music\AIX AVS Test files\Just_My_Imagination_B2.wav

21:01:16 : Test started.
21:02:11 : 01/01 50.0%
21:02:20 : 02/02 25.0%
21:02:28 : 03/03 12.5%
21:02:38 : 04/04 6.3%
21:02:47 : 05/05 3.1%
21:02:56 : 06/06 1.6%
21:03:06 : 07/07 0.8%
21:03:16 : 08/08 0.4%
21:03:26 : 09/09 0.2%
21:03:45 : 10/10 0.1%
21:03:54 : 11/11 0.0%
21:04:11 : 12/12 0.0%
21:04:24 : Test finished.

*---------- *
*Total: 12/12 (0.0%)*
*
---
*
foo_abx 1.3.4 report
foobar2000 v1.3.2
2014/07/11 06:18:47

File A: C:\Users\Amir\Music\AIX AVS Test files\Mosaic_A2.wav
File B: C:\Users\Amir\Music\AIX AVS Test files\Mosaic_B2.wav

06:18:47 : Test started.
06:19:38 : 00/01 100.0%
06:20:15 : 00/02 100.0%
06:20:47 : 01/03 87.5%
06:21:01 : 01/04 93.8%
06:21:20 : 02/05 81.3%
06:21:32 : 03/06 65.6%
06:21:48 : 04/07 50.0%
06:22:01 : 04/08 63.7%
06:22:15 : 05/09 50.0%
06:22:24 : 05/10 62.3%
06:23:15 : 06/11 50.0% <---- difference found reliably. Note the 100% correct votes from here on.
06:23:27 : 07/12 38.7%
06:23:36 : 08/13 29.1%
06:23:49 : 09/14 21.2%
06:24:02 : 10/15 15.1%
06:24:10 : 11/16 10.5%
06:24:20 : 12/17 7.2%
06:24:27 : 13/18 4.8%
06:24:35 : 14/19 3.2%
06:24:40 : 15/20 2.1%
06:24:46 : 16/21 1.3%
06:24:56 : 17/22 0.8%
06:25:04 : 18/23 0.5%
06:25:13 : 19/24 0.3%
06:25:25 : 20/25 0.2%
06:25:32 : 21/26 0.1%
06:25:38 : 22/27 0.1%
06:25:45 : 23/28 0.0%
06:25:51 : 24/29 0.0%
06:25:58 : 25/30 0.0%
06:26:24 : Test finished.

*---------- *
*Total: 25/30 (0.0%)*

Note that these are real world content, grabbed directly from Mark Waldrep's library.  As far as I know, they were not recorded in Carlsbad caves or any other cave for that matter .

Mind you, these are extremely difficult tests to pass so I am not saying that me passing them means everyone else can too.  And at any rate, these are for > CD sampling, not what started this discussion that we don't even need proper 16 bit reproduction.


----------



## bigshot (Nov 4, 2017)

How did he prevent people from doing a simple check for frequencies above 22kHz? How loud were you listening? Is the track normalized up to zero and is it music with normal dynamics?


----------



## amirm

bigshot said:


> How did he prevent people from doing a simple check for frequencies above 22kHz?


That was left the same.  His test was strictly 16 bit vs 24 bits.  Not high sample rate versus low. So sampling rate and content in ultrasonics were the same in both samples.

The AIX tests were high-res vs CD.  Not the archimago.


----------



## bigshot (Nov 4, 2017)

I'd say that you should present yourself to the AES and have them set up an independent test. I bet they'd be very interested in studying you.

Two other quick questions... Were these native 24 bit recordings or tracks from an analogue master? Did they have sections of silence or very low level sound, or are they like most commercial music with quick fade outs into digital silence between tracks? I'm wondering how much time you had to acclimate to low level volume after hearing high level material through the bulk of the song.


----------



## amirm

bigshot said:


> Every hobby attracts people with a specific mental pattern I guess. Audiophile sound seems to attract a wide range of neurosis from OCD to paranoia. Nothing is ever good enough. They always take the status quo and push to make it 20% better, even if it doesn't make any audible difference at all. Not all of us are afflicted with that. Maybe those of us who are free of it just recognize it better when we see it.


No, you are just blinded and biased by objectivists religion.  Everything I have described is based on psychoacoustics, thresholds of hearing, actual controlled listening tests, more research than you can shake a stick at, etc.  You are not reading random audiophile ramblings as you are assuming.  This information used to be part of my job and professional career.  Please don't belittle it this way.  I back everything I say with authoritative references.  I have yet to see you put forward anything of the sort other than, "I say it and you must believe."  I know your arguments cold.  I also know that they have holes in them.

I see you linking to the AES Audio Myths seminar in your signature.  Did you know I hired JJ as my audio architect while working at Microsoft?  And I know Ethan very well.  Here is me passing his audio card loop tests:

First one is for 5th generation which is easier. The next is just for one generation which is much harder:

foo_abx 1.3.4 report
foobar2000 v1.3.2
2014/07/18 06:34:21

File A: C:\Users\Amir\Music\Ethan Soundblaster\sb20x_original.wav
File B: C:\Users\Amir\Music\Ethan Soundblaster\sb20x_pass5.wav

06:34:21 : Test started.
06:35:00 : 01/01 50.0%
06:35:10 : 01/02 75.0%
06:35:21 : 01/03 87.5%
06:35:46 : 02/04 68.8%
06:35:58 : 03/05 50.0%
06:36:19 : 03/06 65.6% <----- Difference found
06:36:28 : 04/07 50.0%
06:36:40 : 05/08 36.3%
06:36:51 : 06/09 25.4%
06:37:02 : 07/10 17.2%
06:37:11 : 08/11 11.3%
06:37:25 : 09/12 7.3%
06:37:36 : 10/13 4.6%
06:37:47 : 11/14 2.9%
06:37:58 : 12/15 1.8%
06:38:10 : 13/16 1.1%
06:38:24 : 14/17 0.6%
06:38:34 : 15/18 0.4%
06:38:50 : 16/19 0.2%
06:38:58 : 17/20 0.1%
06:39:12 : 18/21 0.1%
06:39:21 : 19/22 0.0%
06:39:38 : Test finished.

----------
Total: 19/22 (0.0%)

Above I am showing my search for critical section. So when I tested the single generational loss (i.e. "most difficult") I knew what to listen for:

foo_abx 1.3.4 report
foobar2000 v1.3.2
2014/07/18 06:40:07

File A: C:\Users\Amir\Music\Ethan Soundblaster\sb20x_original.wav
File B: C:\Users\Amir\Music\Ethan Soundblaster\sb20x_pass1.wav

06:40:07 : Test started.
06:41:03 : 01/01 50.0%
06:41:16 : 02/02 25.0%
06:41:24 : 03/03 12.5%
06:41:33 : 04/04 6.3%
06:41:53 : 05/05 3.1%
06:42:02 : 06/06 1.6%
06:42:22 : 07/07 0.8%
06:42:34 : 08/08 0.4%
06:42:43 : 09/09 0.2%
06:42:56 : 10/10 0.1%
06:43:08 : 11/11 0.0%
06:43:16 : Test finished.

----------
Total: 11/11 (0.0%)


----------



## amirm

bigshot said:


> I'd say that you should present yourself to the AES and have them set up an independent test. I bet they'd be very interested in studying you.


I have offered my brain to them after I die but they don't want it because the chair is vegetarian.


----------



## mandrake50

Joke... yes.
Good one


----------



## reginalb

amirm said:


> I have offered my brain to them after I die but they don't want it because the chair is vegetarian.



Quick question for you, at what level noise floor in a room do you feel that beyond 16-bits would be necessary, and in a normal environment do you feel that noise floor could be simulated with noise cancelling headphones, or CIEMs?

Out of curiosity, since this is Head-Fi, do you have a headphone rig? And what does it consist of? You trash the Behringer at one point in here that I use at my desk all the time, and while it certainly has a high noise floor, it disappears once I'm actually playing music.

Of course, I'm also feeding my headphones with a tube amp. Shut up guys, it looks cool on my desk.


----------



## RRod

Just checking out some of these test files: The Just My Imagination tracks are about 1/100s off sync; is that being removed before ABXing them? Even after aligning them, it's pretty clear this isn't a typical resample with a linear-phase filter. There's of course no problem with a different filter but when you start with a difference file that looks audible, it's impossible to say things should be inaudible. So yeah, if you tell me one can ABX these files at Skywalker, sure!


----------



## bigshot (Nov 4, 2017)

I have a Mac so I don't know about this ABX software. Does it play the tracks through or can you loop sections or scrub through them? I can see doing this if you can loop on a very quiet section and boost the volume level.

Did you listen straight through at a fixed volume level Amirm?


----------



## gregorio

amirm said:


> This all gets us back to question he has of "why do you measure and like better performing DACs." *Well, my goal is to see if we can achieve the above criteria because once we do, we are golden.* We as technologies can make a promise to consumers that is backed by data, psychoacoustics and objective measurements. Then it is a durable and reliable argument. Without it it is farce and I won't get behind it.



Amirm, I am NOT disputing your ABX results, I achieved similar results many years ago in DBTs in my studio. I don't think anyone here is disputing that the digital noise floor (dither) can be heard given the correct circumstances. You highlighted "_this may be audible to some listeners at elevated listening levels in a very quiet listening environment_". I would add; "with some parts of some content". For example, a fade out to digital silence, which is often required in music (particularly acoustic music genres) if the final note decays for longer than is judged to be aesthetically desirable or if the note decays into the environmental noise floor of the recording, so all we're left with is that noise floor which obviously has to end at some point, either abruptly when the track ends or potentially less jarringly if we fade it out. However, if we're talking about "fidelity", then it is not expected/desired that consumers will actually hear the fade out all the way to the digital noise floor, it is expected that the fade out will at some point disappear beneath the noise floor of the consumers' listening environment, significantly before the digital noise floor is reached. To be absolutely certain of this, even in the most extreme "real life" consumer circumstances, we have the option of decreasing the digital noise floor by using noise-shaped dither and indeed, the use of noise-shaped dither has been pretty standard practice when distributing 16bit music for roughly 20 years, not withstanding the fact that even with good equipment, in a decently quiet environment and at somewhat/slightly elevated levels, listeners have been shown to not even be able to hear the difference between truncation and TDPF dither, let alone between TDPF dither and noise-shaped dither. Of course, even noise-shaped dither is audible if we have a very quiet listening environment and elevate the listening level enough. But we are talking about test conditions, conditions designed to enable the detection of dither NOT "real life", because in real life those conditions do not occur unless we are testing! In real life, in "a very quiet listening environment" we do NOT elevate listening levels, we do the exact opposite! And, all this only really applies to music content, in film (which you quoted extensively) we have a manufactured noise floor and that's what we typically fade into, not even into the environmental noise floor of the consumers' listening environment (the populated cinema), let alone the digital noise floor. 

Referring to what I've quoted above, while in my last paragraph (and previously) I disagree with the level at which you've defined "golden" in real life, I agree entirely with what you've stated and I certainly appreciate your published measurements and want to know of products which fall below "golden". But, what about the other end of the spectrum? While we disagree on what is real life, even taking your criteria rather than mine, what about products which don't just achieve your criteria but exceed them, what is there beyond "golden" and how could it benefit anyone except marketers or those interested in a purely academic engineering exercise? You seem to be avoiding this question, no matter how I ask it!

G


----------



## ev13wt

E-Stat, is it you?


----------



## castleofargh

gregorio said:


> Amirm, I am NOT disputing your ABX results, I achieved similar results many years ago in DBTs in my studio. I don't think anyone here is disputing that the digital noise floor (dither) can be heard given the correct circumstances. You highlighted "_this may be audible to some listeners at elevated listening levels in a very quiet listening environment_". I would add; "with some parts of some content". For example, a fade out to digital silence, which is often required in music (particularly acoustic music genres) if the final note decays for longer than is judged to be aesthetically desirable or if the note decays into the environmental noise floor of the recording, so all we're left with is that noise floor which obviously has to end at some point, either abruptly when the track ends or potentially less jarringly if we fade it out. However, if we're talking about "fidelity", then it is not expected/desired that consumers will actually hear the fade out all the way to the digital noise floor, it is expected that the fade out will at some point disappear beneath the noise floor of the consumers' listening environment, significantly before the digital noise floor is reached. To be absolutely certain of this, even in the most extreme "real life" consumer circumstances, we have the option of decreasing the digital noise floor by using noise-shaped dither and indeed, the use of noise-shaped dither has been pretty standard practice when distributing 16bit music for roughly 20 years, not withstanding the fact that even with good equipment, in a decently quiet environment and at somewhat/slightly elevated levels, listeners have been shown to not even be able to hear the difference between truncation and TDPF dither, let alone between TDPF dither and noise-shaped dither. Of course, even noise-shaped dither is audible if we have a very quiet listening environment and elevate the listening level enough. But we are talking about test conditions, conditions designed to enable the detection of dither NOT "real life", because in real life those conditions do not occur unless we are testing! In real life, in "a very quiet listening environment" we do NOT elevate listening levels, we do the exact opposite! And, all this only really applies to music content, in film (which you quoted extensively) we have a manufactured noise floor and that's what we typically fade into, not even into the environmental noise floor of the consumers' listening environment (the populated cinema), let alone the digital noise floor.
> 
> Referring to what I've quoted above, while in my last paragraph (and previously) I disagree with the level at which you've defined "golden" in real life, I agree entirely with what you've stated and I certainly appreciate your published measurements and want to know of products which fall below "golden". But, what about the other end of the spectrum? While we disagree on what is real life, even taking your criteria rather than mine, what about products which don't just achieve your criteria but exceed them, what is there beyond "golden" and how could it benefit anyone except marketers or those interested in a purely academic engineering exercise? You seem to be avoiding this question, no matter how I ask it!
> 
> G


Amirm is making me think(which is always good^_^). I tend to only consider 2 logical desires. going for the best fidelity possible no matter the magnitude of improvement(objective fidelity to the max with measurements as a guide). and going for the best subjective sound where anything beyond what I notice is meaningless because I don't notice it. but clearly when I base a listening test on my listening habits, I don't consider that some people have different listening habits. but even more, I don't consider that some people are interested in any potentially audible difference under any potential circumstance, ever. when on the contrary, I limit my listening tests to my gears, my "habitat", my music, my average listening preferences. so my results while the most relevant for my life and I see no reason to change that, are different from the very best hearing threshold I could reach under different circumstances.  and obviously different from the best someone else could hope to achieve when putting his heart into it. 

now if anything, this convinces me even more that I, castleofargh, have absolutely nothing to gain from more than 16bits and that I could live perfectly happy with 12 or 13. to come back to the test tone at -90dB argument, indeed assuming a 106dB SPL level, going 90dB down is still very relevant and audible to me as I don't have music playing at the same time. but there is another twist to that. my usual listening level will have 1khz peak at around 60/65dB SPL with small variation depending on the IEM's own FR. so taking the test tone 90dB below that isn't giving much audibility anymore and the example isn't one anymore. not that it was evidence of anything in isolation without music playing at the same time, but I'm adding my own personal circumstance that obviously shouldn't be used as reference for all humans listening music. 

all that to say, I need to think more about the subjective aspect of listening tests.


----------



## bigshot (Nov 5, 2017)

Amirm, to make it easier for you to reply to my questions, I've gathered them together into one post here for you.

How loud were you listening?

Is the track normalized up to zero and is it music with normal dynamics?

Were these native 24 bit recordings or tracks from an analogue master?

Did they have sections of silence or very low level sound, or are they like most commercial music with quick fade outs into digital silence between tracks?

How much time did you have to acclimate to low level volume after hearing high level material through the bulk of the song?

I have a Mac so I don't know about this ABX software. Does it play the tracks through or can you loop sections or scrub through them?

Did you listen straight through at a fixed volume level Amirm?

Thanks for the answers to these questions, they'll help me understand your results better.


----------



## bigshot (Nov 5, 2017)

castleofargh said:


> I tend to only consider 2 logical desires. going for the best fidelity possible no matter the magnitude of improvement(objective fidelity to the max with measurements as a guide). and going for the best subjective sound where anything beyond what I notice is meaningless because I don't notice it. but clearly when I base a listening test on my listening habits, I don't consider that some people have different listening habits. but even more, I don't consider that some people are interested in any potentially audible difference under any potential circumstance.



I think that people who engage in absolutist thinking tend not to listen to much music. They probably focus on the equipment and music is just like gasoline to keep the equipment running. I participate in several music forums as well, and I've found that when someone asks a question like "What is the one single best version of a Beethoven symphony from both a sound and performance standpoint?" they usually just mean "from a sound quality standpoint". If you suggest an analogue recording, or God forbid Toscanini or Furtwangler, they won't even consider it, no matter how good the performance is. Yet they'll gladly accept a routine performance by a no-name Eastern European regional orchestra if it was recorded this year and it's on SACD. Just because people are interested in high fidelity sound, it doesn't mean they are interested in music. And it naturally follows that they have no normal listening habits. That's why they don't understand people who apply audio standards to the circumstances in which they'll be using the equipment.

That's OK though, because I don't understand someone who would spend tens of thousands of dollars on fancy stereo equipment and then have less than a hundred albums in their collection to listen to. I've spent more on media in my lifetime than anyone ever spent on a stereo system- more than some people spend on a house. My equipment gets a workout every single day. But the equipment isn't my focus. So when I think about specs, I relate them to how I'm going to use the stuff. If that ends up saving me a few thousand dollars on electronics, that just means that I can afford a nice big box of media from Amazon instead. So much the better. The postman calls me Mr Amazon already!

When I go to someone's house, and they have a fabulous library, I look at the books. I don't look for exotic woods or hand carved cabinetry on the shelving. It's the same with home audio. I admire someone with a well curated music collection. I don't care so much if the equipment they play it on is perfectly functional but nothing fancy.



castleofargh said:


> I need to think more about the subjective aspect of listening tests.



I think it's best to define what the purpose you're testing for is. If you're testing to find a way to prove you hear things no one else can, then you might design a different sort of test than if you're just testing to see what the threshold is for a piece of equipment you plan to use for normal listening in your home.


----------



## JaeYoon

bigshot said:


> I think that people who engage in absolutist thinking tend not to listen to much music. They probably focus on the equipment and music is just like gasoline to keep the equipment running. I participate in several music forums as well, and I've found that when someone asks a question like "What is the one single best version of a Beethoven symphony from both a sound and performance standpoint?" they usually just mean "from a sound quality standpoint". If you suggest an analogue recording, or God forbid Toscanini or Furtwangler, they won't even consider it, no matter how good the performance is. Yet they'll gladly accept a routine performance by a no-name Eastern European regional orchestra if it was recorded this year and it's on SACD. Just because people are interested in high fidelity sound, it doesn't mean they are interested in music. And it naturally follows that they have no normal listening habits. That's why they don't understand people who apply audio standards to the circumstances in which they'll be using the equipment.
> 
> That's OK though, because I don't understand someone who would spend tens of thousands of dollars on fancy stereo equipment and then have less than a hundred albums in their collection to listen to. I've spent more on media in my lifetime than anyone ever spent on a stereo system- more than some people spend on a house. My equipment gets a workout every single day. But the equipment isn't my focus. So when I think about specs, I relate them to how I'm going to use the stuff. If that ends up saving me a few thousand dollars on electronics, that just means that I can afford a nice big box of media from Amazon instead. So much the better. The postman calls me Mr Amazon already!
> 
> ...


This is problem with a lot of audiophiles on headfi. They spend more time listening to their equipment than music itself.


----------



## amirm

Ah, multi-part questions.  Is there a Jeopardy daily double to go with that?  



reginalb said:


> Quick question for you, at what level noise floor in a room do you feel that beyond 16-bits would be necessary, and in a normal environment do you feel that noise floor could be simulated with noise cancelling headphones, or CIEMs?


The most sensitive area of your hearing is between 2 and 4 Khz.  Thankfully just about every headphone provides good bit of external noise reduction in that region.  Here is the venerable HD600 for example from innerfidelity measurements:






IEMs though provide much better isolation though and that is what I used for critical listenings like the ones i posted.  Here is the Etymotic ER4PT for example: 





60 db reduction relative to ambient noise floor is superb.  What's more, headphones sound going to left channel can't mask the sound going to right channel.  This again increases sensitivity. 

I can go on but you are sitting very pretty with headphones as far as eliminating noise from around you.

Now, you are asking me what you can hear and I can't answer that without testing you.  For good or bad, vast majority of audiophiles lack critical listening abilities and flunk even tests of lossy codecs to CD.  And then there are people like me and others in the middle.  Without testing your listening abilities, it is impossible to know if need beyond 16.

*Please note that this discussion did not start with the need for > 16 bits.*  The argument started with Bigtop complaining that we don't even need to know have good response in the rightmost bits of a 16 bit sample!  In other words, he is advocating 14 or 15 bits.  That is a much easier case to make but again, I have seen countless audiophiles flunk that test too so I can't tell you what you can hear.  I can tell you that I can hear that difference in blind listening tests and with content that is randomly chosen and not designed to show such differences no less.



> Out of curiosity, since this is Head-Fi, do you have a headphone rig? And what does it consist of? You trash the Behringer at one point in here that I use at my desk all the time, and while it certainly has a high noise floor, it disappears once I'm actually playing music.
> 
> Of course, I'm also feeding my headphones with a tube amp. Shut up guys, it looks cool on my desk.


I will respond to the Behringer bit in my next post as this is getting long.  As far as what headphones I own, I am embarrassed to say too many .  Here is a quick list from memory:

* Stax SR-009, SR-407 and SR-307 electrostatic headphones.  I have three Stax headphone amps to go with them with two out of three being tube based: srm-007t, srm-006t and srm-313.
* Sony MDRv6
* Sennheiser HD600 which I donated to my son and have purchased an HD650 to arrive tomorrow.
* Grado 80 which again I donated to my son and will get the new version shortly

For IEMs, I own a number of Etymotic units with the latest one being ER4S. I also own a Shure one whose model escapes me (was around $200).  I also have a bunch of other random ones like Paradigm, etc. which I don't use.

I am starting to test headphone amplifiers on ASR Forum so the list may grow.

So what do I win???


----------



## amirm

RRod said:


> Just checking out some of these test files: The Just My Imagination tracks are about 1/100s off sync; is that being removed before ABXing them?


That was discovered in multiple forums when the test was published.  I think some people cheated (and said so) by using that and started to dismiss results from others saying that is what it was used.  In my ABX testing with that delay being there, I did not base any of my testing on detecting such tricks.  It is a dangerous thing to post such results, then have someone remove the gap and fail to do so later.

I forget whether the later revisions of the test removed that or not.  I also re-sampled the files myself and ran those with the same outcome:

foo_abx 1.3.4 report
foobar2000 v1.3.2
2014/08/12 19:03:48

File A: C:\Users\Amir\Music\AIX AVS Test files\On_The_Street_Where_You_Live_A2.wav
File B: C:\Users\Amir\Music\AIX AVS Test files\On_The_Street_Where_You_Live_A2-amir converted.wav

19:03:48 : Test started.
19:06:50 : 01/01  50.0%
19:07:25 : 02/02  25.0%
19:07:34 : 02/03  50.0%
19:08:03 : 03/04  31.3%
19:08:14 : 04/05  18.8%
19:08:23 : 05/06  10.9%
19:08:31 : 06/07  6.3%
19:08:41 : 06/08  14.5%
19:08:51 : 07/09  9.0%
19:09:02 : 08/10  5.5%
19:09:10 : 08/11  11.3%
19:09:50 : 09/12  7.3%
19:10:00 : 10/13  4.6%
19:10:09 : 11/14  2.9%
19:10:19 : 12/15  1.8%
19:10:29 : 13/16  1.1%
19:10:39 : 14/17  0.6%
19:10:53 : 14/18  1.5%
19:11:04 : 15/19  1.0%
19:11:15 : 16/20  0.6%
19:11:29 : 16/21  1.3%
19:11:43 : 17/22  0.8%
19:11:54 : 18/23  0.5%
19:12:13 : 19/24  0.3%
19:12:26 : 19/25  0.7%
19:12:46 : 19/26  1.4%
19:12:50 : Test finished.

 ---------- 
Total: 19/26 (1.4%)

--

The results are statistically significant (anything < 5% total is).    It doesn't meet my standard of 100% confidence and I think I tested again and got there but can't find a record of it easily like above.


----------



## bigshot (Nov 5, 2017)

Have you had a chance to look at my questions yet?



amirm said:


> *Please note that this discussion did not start with the need for > 16 bits.*  The argument started with Bigshot complaining that we don't even need to know have good response in the rightmost bits of a 16 bit sample!



Actually I was saying that noise at -90dB wasn't something that would be a problem for someone listening to music on a home stereo. (I fixed your spell checker error there.) And I wasn't intending to complain or argue. I was just putting specs in perspective.


----------



## amirm

reginalb said:


> You trash the Behringer at one point in here that I use at my desk all the time, and while it certainly has a high noise floor, it disappears once I'm actually playing music.


I don't trash "Behringer."  I said that the $29 one doesn't perform as well as I like.  Here is the full review: https://www.audiosciencereview.com/...eview-and-measurements-behringer-uca222.2036/

Here is a measurement from that comparing Behringer UCA222 against my laptop's built-in headphone out:







My laptop outperforms both in broadband noise and jitter/distortion spurs.  It does the same on linearity of the rightmost 2 bits of 16 bit data (don't be confused by the "24 bit" moniker in this test):






On top of that my laptop has far higher output than the anemic one put out by the UCA222.

This is the data.  It can only be challenged with new data not being grumpy that your DAC of choice is looking bad.    That can't be helped.  I buy these products on my own, review them on my own dime and publish them at no cost or advertising to anyone.  You can ignore them but you can't complain about them.  The UCA222 is old news, uses knock-off DAC chip and is highly limited to 44.1 and 48 Khz sampling with no support for async USB.  Based on all of this I cannot recommend it.

And oh, until recently the Behringer UMC-204HD at just $79 was my recommended DAC.  Here is that data which started this argument:






So I have nothing against Behringer at all.  That unit by the way has been unseated by the Topping D30 which is $120 and produces most excellent results:






Again, this shows how clean the rightmost 2 bits of 16-bit data are. So no argument for > 16 bits.


----------



## amirm

gregorio said:


> Amirm, I am NOT disputing your ABX results, I achieved similar results many years ago in DBTs in my studio.


Well then it would have been nice to have some support on them rather that stay on the side letting folks create doubt about them.



> I don't think anyone here is disputing that the digital noise floor (dither) can be heard given the correct circumstances. You highlighted "_this may be audible to some listeners at elevated listening levels in a very quiet listening environment_". I would add; "with some parts of some content". For example, a fade out to digital silence, which is often required in music (particularly acoustic music genres) if the final note decays for longer than is judged to be aesthetically desirable or if the note decays into the environmental noise floor of the recording, so all we're left with is that noise floor which obviously has to end at some point, either abruptly when the track ends or potentially less jarringly if we fade it out. However, if we're talking about "fidelity", then it is not expected/desired that consumers will actually hear the fade out all the way to the digital noise floor, it is expected that the fade out will at some point disappear beneath the noise floor of the consumers' listening environment, significantly before the digital noise floor is reached.


Fade out is but one condition of audibility here.  There are lots of others such as notes decaying into background.  And recordings that are not at 0 dbFS and hence are listened to at elevated levels, leaving you much less dynamic range.

Ultimately remember, as I keep saying, the argument started with not needing 16 bits.  Are you saying all of this in the context of that too?



> To be absolutely certain of this, even in the most extreme "real life" consumer circumstances, we have the option of decreasing the digital noise floor by using noise-shaped dither and indeed, the use of noise-shaped dither has been pretty standard practice when distributing 16bit music for roughly 20 years....


It has been known that many years and more.  But standard in use?  No way.  As you note below, people doubt it is needed and do without dither altogether let alone using noise-shaping.  Do ahead and examine your library of music and report back on what percentage of them use noise shaping.



> ... not withstanding the fact that even with good equipment, in a decently quiet environment and at somewhat/slightly elevated levels, listeners have been shown to not even be able to hear the difference between truncation and TDPF dither, let alone between TDPF dither and noise-shaped dither. Of course, even noise-shaped dither is audible if we have a very quiet listening environment and elevate the listening level enough. But we are talking about test conditions, conditions designed to enable the detection of dither NOT "real life", because in real life those conditions do not occur unless we are testing! In real life, in "a very quiet listening environment" we do NOT elevate listening levels, we do the exact opposite! And, all this only really applies to music content, in film (which you quoted extensively) we have a manufactured noise floor and that's what we typically fade into, not even into the environmental noise floor of the consumers' listening environment (the populated cinema), let alone the digital noise floor.


I am not here to put restriction on music, where it is listened, or how it is produced. I am here to advocate excellence in engineering and what must be there to achieve transparency in all cases.

And no, there was next to nothing about "film" in my article.  I wrote that for Widescreen Review Magazine so there is a tiny reference.  But the rest of the article and references within have little to do with film.  Here is one graph from my article again:






Davies hall in San Francisco is a concert hall.  Even skywalker sound is used for musical scores devoid of manufactured sound you mention.  Here is an example:



The lesson there is that we cannot use single number SPL values.  But rather we need to analyze the spectrum of noise and compare it to Hearing Threshold.  Once we do, we see that recording venues can hit that threshold of hearing and as such be totally silent.  So the argument that no recording is silent enough exists.

Furthermore, we can hear below noise floor of a room --- both in recording and playback.  I can go on but you really short changing what I wrote and underlying research which has been peer reviewed and published in prestigious audio journal.  Not sure what we are doing in this subform if the first thing we do is dismiss such research.



> Referring to what I've quoted above, while in my last paragraph (and previously) I disagree with the level at which you've defined "golden" in real life, I agree entirely with what you've stated and I certainly appreciate your published measurements and want to know of products which fall below "golden". But, what about the other end of the spectrum? While we disagree on what is real life, even taking your criteria rather than mine, what about products which don't just achieve your criteria but exceed them, what is there beyond "golden" and how could it benefit anyone except marketers or those interested in a purely academic engineering exercise? You seem to be avoiding this question, no matter how I ask it!
> 
> G


My criteria is two fold:
1. For every system out there, I like to see clean, unadulterated reproduction of 16 bits.  This is not hard to do and is dirt cheap as per my $120 DAC recommendation.  The Topping D30 is a Chinese product and I assure you, no money is spent on marketing it in that cost which is less than 10 CDs you may buy.

2. For high performance systems, I like to see full 20 bit reproduction as to provide complete transparency.  The latest Benchmark HC3 gets to 21 bits and it has my praise for that.  And at $2K they charge for it, it is "reasonable" to me in the context of a high-end, ultimate DAC you could get that you can keep for years and years.  Again, you are not rewarding any "marketing."  You are rewarding excellence in engineering in a low-volume market which drives the costs up.

As you see, I have no patience for people who try to dumb things down below #1.  Who are they protecting with that???  Saving people from spending $120 instead of $29?  Let's get real.


----------



## bigshot

I’m going to reduce my questions down to one in hopes you’ll answer it. Did you gain ride the test, or did you have a fixed listening level throughout the track?


----------



## reginalb

amirm said:


> I don't trash "Behringer."  I said that the $29 one doesn't perform as well as I like.  Here is the full review: https://www.audiosciencereview.com/...eview-and-measurements-behringer-uca222.2036/



I didn't say you trash Behringer, I said you trashed _the_ one that I use. And don't worry, I don't care. I bought it for features (the ADC) at a price point that I was willing to pay for something that I do as a hobby. I only started feeding my amp with it because it was sitting around, and I had an amp with no DAC built in. That it outputs at a lower level than a computer is of no consequence when I'm just using the line-out off the DAC.


----------



## amirm

bigshot said:


> I’m going to reduce my questions down to one in hopes you’ll answer it. Did you gain ride the test, or did you have a fixed listening level throughout the track?


You are not going to learn anything by asking me to help you with your argument.  Why don't you run a blind test, ride the gain, horses or even a donkey and see if you can pass them.    Then you will speak from experience.


----------



## castleofargh

bigshot said:


> ...I think it's best to define what the purpose you're testing for is. If you're testing to find a way to prove you hear things no one else can, then you might design a different sort of test than if you're just testing to see what the threshold is for a piece of equipment you plan to use for normal listening in your home.


oh I'm very clear about the question I'm trying to answer when I set up a test. my mistake is more about assuming I know what someone else is talking about, because I think he's trying to answer the very same question I had. but sometimes, he's not and it takes me a lot of time to see it. 
this results in taking experiences out of their initial context by mistake. 
I don't know if I'm clear or digging even deeper ^_^.


----------



## bigshot (Nov 6, 2017)

amirm said:


> You are not going to learn anything by asking me to help you with your argument.  Why don't you run a blind test, ride the gain, horses or even a donkey and see if you can pass them.    Then you will speak from experience.



OK. I gave you a chance to explain. The caginess of your replies says a lot more than your cut and paste plain text ABX test results. I think you cut the tracks down to a tiny sliver of fadeout, then boosted the volume to an unGodly level so you could tell them apart. That doesn't take "experience" or "training" to discern. Even with with her hearing aid on low batteries, my grandmother could tell the difference between 16 and 24 if you turn the volume up high enough. If you're trying to impress us to get us to follow your review site, you're doing it the wrong way. If you're trying to prove you can hear stuff that no one can hear at normal listening volumes, you might as well the math yourself and edit the text of the test results before you post them. That would save a lot of time and accomplish pretty much the same thing.



> I also re-sampled the files myself



Yes.


----------



## amirm

bigshot said:


> OK. I gave you a chance to explain.


Well, in that case, thank you very much!  



> The caginess of your replies says a lot more than your cut and paste plain text ABX test results. I think you cut the tracks down to a tiny sliver of fadeout, then boosted the volume to an unGodly level so you could tell them apart. That doesn't take "experience" or "training" to discern. Even with with her hearing aid on low batteries, my grandmother could tell the difference between 16 and 24 if you turn the volume up high enough. If you're trying to impress us to get us to follow your review site, you're doing it the wrong way. If you're trying to prove you can hear stuff that no one can hear at normal listening volumes, you might as well the math yourself and edit the text of the test results before you post them. That would save a lot of time and accomplish pretty much the same thing.


You have incredible imagination there and assume people have awfully low ethical standards.  Be that as it may, the results of those tests were intensely argued about on multiple forums going on for days and weeks by people far more aggressive and knowledgeable than you.  To your earlier suggestion of donating myself to AES, the results were also shared with chair of high-resolution audio group, Vicki Melchior and the rest of the team in that working group.  I have to tell you, folks are tired of constant tune you sing that fidelity doesn't matter.  This is why latest papers by Stuart et. al. were welcome (see my digest and article: https://audiosciencereview.com/forum/index.php?threads/high-resolution-audio-does-it-matter.11/).  This work also generated a lot of buzz in forums and industry resulting in me writing another follow up which answers your question (partly) about how ABX tests work: https://audiosciencereview.com/forum/index.php?threads/statistics-of-abx-testing.170/.

I suggest that instead of this kind of personal tone, you spend your energy learning about blind tests.  Google is your friend.  As is ASR Forum, Hydrogen Audio, etc.  Until such time that you actually put yourself in such a situation, i.e. controlled blind testing, I suggest not going after people so aggressively as you have been doing.  Being an objectivist require more than spending time on forums and reading its ten commandments.  If you think I am using tricks, try to duplicate my results.  Don't assume those techniques work or work all the time.  I have presented plenty of tests for you to run and try to duplicate -- cheating or not.

On issue of cheating, later versions of ABX plug-in for foobar have checksums to guard against manipulating the files in any way.  Here is an example of me passing 30 Hz jitter (very hard to do due to high level of masking) showing these safeguards:

foo_abx 2.0 beta 4 report
foobar2000 v1.3.5
2014-12-09 14:24:40

File A: 30 Hz jitter strong level .025.flac
*SHA1: 54719c17fd29d0546b79f50bd7e3c61de1dd025d*
File B: no  jitter.flac
*SHA1: 262cd6c4d4c73502a0142f867b00aae013fd13ce*

Output:
DS : Primary Sound Driver

14:24:40 : Test started.
14:25:00 : 01/01
14:25:06 : 02/02
14:25:16 : 03/03
14:25:21 : 04/04
14:25:27 : 05/05
14:25:34 : 06/06
14:25:39 : 07/07
14:25:45 : 08/08
14:25:51 : 09/09
14:25:56 : 10/10
14:25:56 : Test finished.

 ----------
Total: 10/10
Probability that you were guessing: 0.1%

 -- signature --
*ba16bda939028d34d8b131283f9d46709dab36f9*

There is a tool where you feed these to it and it will verify if you have or have not messed not only with the audio files but also the text output of foobar ABX plugin: http://www.foobar2000.org/abx/signaturecheck

When I feed the above text to it, it outputs:

*Signature matches; the log appears to be valid.*​
You can try it yourself and verify the same.  Cheat and this kind of measure comes along and hangs you by your shorts!   

Again, go and see if you can pass all of these tests using whatever method you choose.  Regardless of outcome, you will gain a new appreciation and firsthand feel for these topics.  There is a great path here to becoming a critical listener.  Once you get there, you will see how there is a gap between you and many others.  It doesn't come easy or cheap though.  You must put in the time.


----------



## spruce music

Don Hills said:


> The masking demonstration that clinched it for me was the music with the sousa band mixed in at about a -60 db level. (Anyone have the link? I can't find mine.)



http://www.libinst.com/diffmaker_example_files.htm

Listener challenge down near the bottom of this page.  Guy who made Diffmaker.


----------



## amirm

bigshot said:


> Actually I was saying that noise at -90dB wasn't something that would be a problem for someone listening to music on a home stereo. (I fixed your spell checker error there.) And I wasn't intending to complain or argue. I was just putting specs in perspective.


Well, we have what you said:



bigshot said:


> I don't understand why someone would say that one DAC is better or worse than another because it measures higher or lower while still being well beyond the threshold of transparency. I judge equipment by its ability to do the job of playing music for human ears. I haven't run across any player or DAC or cable or amp in the past 20 years that doesn't fit the bill on that score. Sound Science people can sometimes be just as prone to focus on stuff that doesn't matter as audiophools. If they enjoy the mental exercise, that's fine. But I sure hope no one takes this stuff into account when they make buying decisions. It's a waste to spend money on things you can't hear. Better to focus on features and usability.



You were selling people on anything that produces music, by definition must be good and better than what we hear.  That assertion has been made by you repeatedly but with nary of a reference, research study, nothing really.  Just an assumption that this must be the case.  And hence, no one should bother or care about the work I am doing.  That is an insult besides lack of understanding of audio fidelity and requirements for channel transparency for all listeners and content.

You talk about "20 years" of DAC experience.  Exactly how many DACs have you used and how do you know they meet the threshold of detection?  What formal tests did you do?  Do you know what test would be revealing of such?

I have had at least three DACs that easily transmitted computer noise through their output!  I have had two other DACs that clip samples near 0 db causing buzzing.  I have had DACs that perform worse than what is in your computer already.  Currently I probably have 10-15 DACs with more coming.  So please put aside your assumption that you already know what you need to know. You don't.  We have fed you are PR lines and you are running with them without the proper knowledge and experience to defend them.

There is so much garbage here because both objectivists and subjectivists have given a pass to equipment makers to release products with nary of a measurement.  The is more information on a tire sidewall than there is for audio gear! Subjectivists say measurements don't matter.  Extreme objectivists say the same because they are all perfect for our ears.  Well guess what, neither is correct.  There is less or more competence, science and engineering in some products or others.  The only way to get there is to examine them on our nickel which is what I am doing.  Last thing we need is someone running interference to stop people from either measuring or paying attention to the results.

So please think through what you are doing.  You are not doing any favor to the community.  You are protecting manufacturers and allowing them to build subpar equipment.  Spend the energy learning what is being measured, why it may matter, and advocate excellence in engineering.  Don't belittle it because it makes for less rosy chanting like for objectivism.


----------



## spruce music

amirm said:


> Well, we have what you said:
> 
> 
> 
> ...



I think you make a very important point.  I have assumed mostly you can forget about most modern gear as having a sound.  I think probably more than any other time in history that is true.  However some people design for a sound which isn't about fidelity.  And some seem intent on shearing the sheep just because conditions have made it possible in the subjectivist camp.  I think Schiit products are a good example.  Almost all have some oddity to their operation, they don't have terrific measured specs, their reputation is pretty good because they put a human face on their company in forums like this one.  That is good, well except for some of the product. 

I do remember when Audio (and Stereo Review) did testing of things they reviewed.  Mostly things met spec or exceeded it or came close.  Amps adhered more or less to the FTC guidelines.  With the rise of subjective audiophiles measurements being meaningful were sneered at.  Thankfully JA at Stereophile and people at Soundstage.net still do measurements, but so many publications don't. I understand it somewhat with the proliferation of products who could keep up.  And hell must be the guy who measures every aspect of AVR's for a living.  Yet some products are taking liberties with the situation. They feel safe making claims.  Using chip specs as listed specs without showing they actually managed that or just making things up or saying they don't believe in your usual measurements.  Oh well, long as it doesn't hurt sales nothing is likely to change. Seems strange to disagree with someone trying to somewhat dot the I's and cross the T's.  Providing info on products actual performance.


----------



## bigshot (Nov 7, 2017)

amirm said:


> You have incredible imagination there and assume people have awfully low ethical standards.



You ask me to believe you when I offered to set up a test for you that you weren't in control of, and you ignored me. I think you're creating your own test so you can control the outcome. That's why DBX has the DB in it.

I'm down to reading the first line or two of your posts now. No need to type out long justifications.


----------



## gregorio (Nov 7, 2017)

amirm said:


> [1] Well then it would have been nice to have some support on them rather that stay on the side letting folks create doubt about them.
> [2] Fade out is but one condition of audibility here.  There are lots of others such as notes decaying into background.
> [3] And recordings that are not at 0 dbFS and hence are listened to at elevated levels, leaving you much less dynamic range.
> [4] It has been known that many years and more.  But standard in use?  No way.
> ...



1. I'm on both sides! I support your (and my) DBT results which demonstrate it can be detected under test conditions but I also support those "folks" who are effectively saying it can't under normal listening conditions. Can't you see/admit that both sides can simultaneously be correct?
2. Notes decaying into what background? The background you quote of an empty hall with no HVAC or the background of a hall full of musicians and commonly therefore a legal requirement to have the HVAC on? And obviously, if it's the former, who is playing the notes which decay into that background?
3. True but of course if the recording peaks at say -6dBFS and you compensate by elevating the gain, then you do not have a 16 bit recording, you only have 15 bits because the MSB in not being used.
4. Yes it's at least a standard recommendation and many commercial engineers apply noise-shaped dither as standard. I agree though that it's not always applied ...
4a. Isn't this statement effectively an argument against your assertion? Those "people" are content creators, they're doing their creating in reasonable to excellent listening/monitoring environments and at least some of the time at somewhat elevated levels and yet they're not aware of even truncation distortion, let alone noise-shaped dither! Or, if they are aware they choose not to apply dither, why do you think that is?
5. Come on, do you really need your own article quoting back to you? "_Before diving deep let’s cover some basics. Movie soundtracks come in digital form on the Blu-ray disc._". "_If you have a dedicated theater or listening space_". "_you can convince yourself that we could go back to cassette tapes and still have sufficient dynamic range for our movies!_". "_Let’s review the measurements he took with respect to noise floor for a sampling of live halls and a film recording studio_". "When you stand outside of your theater..."
6. Agreed BUT (!) if you are going to quote real life then that means not ONLY analysing the noise of empty concert halls and recording studios (with the HVAC turned off)! You have to also look at those halls with musicians in them, you also have to look at the noise/signal ratio of the mics + pre-amps and the "real life" usage/positioning of them, plus what the creators/producers wish to achieve! And thanks for your example video. You did notice that there was a piano and pianist in the studio didn't you? Did you also notice the mics used, where they were positioned and considered the impact on noise/dynamic range that "real life" situation would have? Apparently not, but why? Do we only need to "analyse the spectrum of the noise" which supports your argument or should we analyse the spectrum of ALL the noise which exists in "real life"?
And BTW, yes, I know what Davis Hall is, I've worked there, as well as many, many others. I've also worked extensively with the BBC, their recording rooms and the concert venues where they record. I've never been to Skywalker Sound but I know very well what it is.
7. Exactly, that is exactly my point, a point which it's getting difficult not to assume you are now wilfully ignoring/avoiding ...
7a. AGAIN! If 20 bit reproduction provides "complete transparency" or as you described it before, is "golden", what is there beyond complete transparency/golden? What audible benefit does the 21 bits of the HC3 give you that a "completely transparent" and "golden" 20 bit DAC does not give you? How is that extra bit "reasonable" except in terms of a bigger number for marketing or academic engineering excellence? ...

7b. Amirm you are obviously an intelligent man and apparently well informed. So why are you playing the game of mis-direction and omission, unless it's to fulfil a some personal agenda? You are omitting many of the real life practicalities of recording and the production/mastering goals and you are mis-directing with your statement quoted here. Yes, no one is disagreeing that it's very important to have measurements, to identify under-performing units but the issue here is also the other side of the equation, the side which you CONTINUALLY AVOID, what about the over-performing units. Assuming your quoted $120 D30 provides your 20bit "completely transparent"/"golden" performance requirement and using your also quoted $2k HC3, then what about the other side of the equation: *"saving people from spending $2k instead of $120"?* What audible benefit does that extra $1,880 provide, if $120 already gives you "golden"/"completely transparent"?

G


----------



## Darren G

A 90 degree point of view -

I was a first generation CD adopter.  A few hours of WOW, followed by a long period of 'this sucks'.  Okay, well that was long time ago, and digital audio quality is amazing today.  I write that only to point out, I agree that just because it's digital does not mean flawless.

Still, the harsh truth I realized about myself... nothing can cure obsessively looking for flaws.  If someone is dead set on finding flaws, that is all they are going to do, and it won't matter how objectively correct (or incorrect) the gear is.  They are going to find a flaw.  They will convince themselves there is a flaw, and there are no objective arguments that will sway them.  That is not to say there is no objective truth, just that the only thing that can fix an obsessive focus on flaws requires a change in personal focus.  Learning to enjoy the music first, and focusing on flaws second (if even that), is the only way to really get to that point of the gear is 'good enough'.


----------



## bigshot

OCD, autistic obsession and paranoia drive a lot of hobbies. Not just audiophila. I'm always amazed when I see people focusing on making sure that every one of their blu-rays is lined up on the shelf in alphabetical order, or worrying about not having one or two songs out of Frank Sinatra's output, or hauling around big ass WAV files on their phone because they can't sleep at night worrying that smaller file sizes might be throwing out something they might want. None of that stuff makes sense. I understand that people with these sorts of problems can't help themselves. I try to calm them down with facts and logic, but if that doesn't work, I just let them spin their wheels. If they keep their obsessions to themselves and don't try to visit them on other people, it's fine.


----------



## amirm (Nov 7, 2017)

bigshot said:


> I think you're creating your own test so you can control the outcome. That's why DBX has the DB in it.


And foobar ABX fully qualifies for that.  Indeed it is the "gold standard" in online forums even from the most diehard objectivists.  It is why I run it, not because it is my favorite way to do it.

Since you have no familiarity with it, in foobar ABX, you are given the two files and a random version which you have to vote as A or B.  You as the listener have no control whatsoever on what is being played.  And the computer of course is completely unbiased.  It will select A or B randomly as "X" and no way, no how can you game that aspect.

And *every* test and outcome I have posted has been an online challenge created by others.  None were created by me and I had nothing to do with selection of content.

Again, spend five minutes running it and see if you can game it. You will be heavily frustrated.  When I can't tell the difference, the results are really, really poor.  You can't get lucky as  you have to achieve 95% confidence and that can't be done except by remote chance.

Here is an example of me failing to hear a difference in Entreq grounding box:

foo_abx 1.3.4 report
foobar2000 v1.3.2
2016/02/14 08:50:25

File A: C:\Users\Amir\Documents\Test Music\Entreq 2 digital\test_4_output_entreq.wav
File B: C:\Users\Amir\Documents\Test Music\Entreq 2 digital\test_4_output_no_entreq.wav

08:50:25 : Test started.
08:52:22 : 01/01  50.0%
08:52:30 : 01/02  75.0%
08:52:43 : 02/03  50.0%
08:52:51 : 02/04  68.8%
08:53:03 : 02/05  81.3%
08:53:32 : 02/06  89.1%
08:53:58 : 03/07  77.3%
08:54:12 : 03/08  85.5%
08:54:27 : 03/09  91.0%
08:54:31 : Test finished.

 ----------
Total: 3/9 (91.0%)

====

So 91% chance that I was guessing even though I got some right.

Here is another online challenge that I failed at initially:

foo_abx 1.3.4 report
foobar2000 v1.3.2
2014/07/19 07:27:54

File A: C:\Users\Amir\Music\Arny's Generational Loss\sb20x_original.wav
File B: C:\Users\Amir\Music\Arny's Generational Loss\sb20x_pass1f.wav

07:27:54 : Test started.
07:28:25 : 00/01  100.0%
07:28:40 : 00/02  100.0%
07:28:52 : 01/03  87.5%
07:29:04 : 02/04  68.8%
07:29:17 : 03/05  50.0%
07:29:38 : 04/06  34.4%
07:29:50 : 05/07  22.7%
07:30:35 : 05/08  36.3%
07:30:46 : 05/09  50.0%
07:31:02 : 06/10  37.7%
07:31:15 : 07/11  27.4%
07:31:27 : 08/12  19.4%
07:31:43 : 09/13  13.3%
07:31:52 : 10/14  9.0%
07:32:04 : 11/15  5.9%
07:32:15 : 12/16  3.8%
07:32:26 : 13/17  2.5%
07:32:39 : 13/18  4.8%
07:32:54 : 14/19  3.2%
07:33:06 : 15/20  2.1%
07:33:18 : 15/21  3.9%
07:33:41 : 15/22  6.7%
07:34:08 : 16/23  4.7%
07:34:16 : 17/24  3.2%
07:34:26 : 18/25  2.2%
07:34:38 : 19/26  1.4%
07:34:51 : 19/27  2.6%
07:35:05 : 19/28  4.4%
07:35:28 : 19/29  6.8%
07:35:39 : 19/30  10.0%
07:35:41 : Test finished.

 ----------
Total: 19/30 (10.0%)

===

That says there was 90% chance that I was NOT guessing.  But that is not acceptable to me.  If you look toward the end, I started to lose what I thought was a definite difference as failures started to pile up after getting 19 right.

You would do well putting aside that negative energy and insulting remarks and actually run some double blind tests with a "D."  Heck, run it single blind and see if you can pass with the tricks you mention.  If it were easy, tons of people would do it.


----------



## amirm

gregorio said:


> That's the difference! You and the papers you quote are talking about all people and all content, whereas I'm only talking about all people and all commercial content; all commercial music releases, all Radio, all TV and all films. You quote real life but in real life what audio content other than commercial music releases, radio, TV and films are people listening to?
> 
> G


All commercial content?  Forget that.  Tell me how you determined the effective bit depth of music in all the content in your library.  How did you objectively analyze them?  Or is this another "everyone knows" that when we challenge, has no answer?


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## bigshot (Nov 7, 2017)

amirm said:


> And foobar ABX fully qualifies for that.  Indeed it is the "gold standard" in online forums even from the most diehard objectivists.  It is why I run it, not because it is my favorite way to do it.



I'm sorry, I'm sure you are a very nice person in real life, but I don't trust what you say any more. No offense, it's just that you seem to be putting on an act for the forum and I don't think you're being completely honest with us. I'll just leave it at that.



amirm said:


> Tell me how you determined the effective bit depth of music in all the content in your library.



Gregorio is a professional sound engineer. He knows exactly how music is produced and engineered. Of that I have no doubt.


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## JaeYoon (Nov 7, 2017)

bigshot said:


> OCD, autistic obsession and paranoia drive a lot of hobbies. Not just audiophila. I'm always amazed when I see people focusing on making sure that every one of their blu-rays is lined up on the shelf in alphabetical order, or worrying about not having one or two songs out of Frank Sinatra's output, or hauling around big ass WAV files on their phone because they can't sleep at night worrying that smaller file sizes might be throwing out something they might want. None of that stuff makes sense. I understand that people with these sorts of problems can't help themselves. I try to calm them down with facts and logic, but if that doesn't work, I just let them spin their wheels. If they keep their obsessions to themselves and don't try to visit them on other people, it's fine.


I think a lot of audiophiles who cannot sleep without WAV never want to read up on hard work of LAME developers or prowess of QAAC today.

In their mind it's throwing away data they worry they might want. But it may not be perfect, but a lot of work has been done trying to remove all inaudible information and keep pretty much as much as possible or everything that is audible depending on bitrate that a person can find transparent to them.
Like some people might find 128 kbps Lame MP3 not always transparent, but 128 AAC VBR might even do it.

I keep my FLAC at home, and portable devices use lossy. When we are outside and walking about I think those details are last thing we are thinking about. Usually it's other things on our mind, like where we are traveling to, what do we want to do outside, etc.


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## bigshot

I rip everything to AAC 256 VBR and never look back. The CDs get boxed up and stored in the garage.


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## gregorio

amirm said:


> All commercial content?  Forget that.  Tell me how you determined the effective bit depth of music in all the content in your library.  How did you objectively analyze them?  Or is this another "everyone knows" that when we challenge, has no answer?



That's a bizarre question to ask, in light of what I've already said on the matter. Firstly and most importantly, it's an avoidance/deflection from the question/s I asked! And secondly, as I'm sure you are aware, there is no objective measure of dynamic range. The answer to your question depends on how we define dynamic range in the first place and if we're going to talk about fidelity, on the intention of the creators.

You appear to think that I'm trying to discredit you and/or the science, I'm not. It's important to know the ultimate limits of human capabilities under all conditions and that's what science attempts to give us BUT, if you're going to bring real life into it, then the reference has to be all real life conditions rather than all test conditions which do not all occur simultaneously in real life, unless we manufacture them for testing and in real life, commercial content is designed for entertainment purposes, not for the purpose of testing the utmost limits of human capabilities. Indeed, if we define dynamic range as do musicians and if we actually used even say an 80dB range for that purpose, we'd have incompetently produced content! However, the fact that you are taking test figures and erroneously calling them real life figures is besides the main point because my question to you, the one which you apparently refuse to answer, is based of your test figure! 

Amirm, I am trying not to fight with you because most of what you say and do I not only entirely agree with but really appreciate! With such a paucity of reliable information, it's certainly a very worthwhile endeavour to highlight equipment performing poorly relative to it's marketing claims and/or price. However, that's not the only affliction which needs addressing; as technology not only improves but gets cheaper, we've also got the growing problem of over-performance sold as actual audible improvement and not just with some DACs but with the digital audio formats themselves. Therefore, it's also a worthwhile endeavour to highlight when this is occurring!

G


----------



## amirm

bigshot said:


> I'm sorry, I'm sure you are a very nice person in real life, but I don't trust what you say any more. No offense, it's just that you seem to be putting on an act for the forum and I don't think you're being completely honest with us. I'll just leave it at that.


I hear you.  This is one of those things that is hard to believe, i.e. that someone can hear distortions that we ourselves think is an impossibility.  There is fortunately science behind this but one that is not well known outside of industry and research.

The key here is understanding the concept of a trained listener.  No, I am not talking about self-appointment "golden ears."  I am talking about listeners that have gone through training and verification of their listening ability to be well above general public and that includes audiophiles.  A great published example is that of work for Harman in their loudspeaker research through controlled listening tests.  See this example: http://seanolive.blogspot.com/2008/12/part-2-differences-in-performances-of.html







See how much better the discrimination and ability to identify artifacts are among trained listeners compared to other groups.  Assuming that high-end audiophiles are represented by the "audio reviewers" the ability of trained listeners is about 5 times better!

How did that magic come about?  As I mentioned, it is through specialized training.  Fortunately Harman gives away that software and you can try to a) test your own abilities and b) become trained: http://harmanhowtolisten.blogspot.com/

The software is like a video game in that it starts easy and progressively gets more and more difficult.  The concept is simple: you are presented with an original track and another that has been modified by a single filter/EQ changing the frequency response.  When the "Q" (bandwidth) of the filter is large detection is easy as it impacts so many notes.  But as it gets narrower, less of the music spectrum is impacted and the job gets hard.

I remember running that test when it first came out.  I got to level 2 or 3 and could go no further.  Pretty disappointed.    So I practiced some and then gave it up.  Fast forward a year or two later and I was at Harman with Dr. Sean Olive presenting us the same test in one of their reference testing rooms.  Here is a picture of Sean and you can faintly see the How to Listen software output on the projection screen:





What you don't see is behind me which is a dozen high-end audio dealers some of whom are acousticians who had come for this training.

Sean started the program at level 1 and everyone got the answer right more or less to level 2-3 as I had originally.  But the moment it went above that, I and Sean where the only ones who could guess correctly.  I think I got to level 6 before I failed.  That bit of training had made a noticeable difference in my abilities.  My happiness on that front disappeared when Sean continued with utmost ease giving the right answer to levels 7,8, 9, etc.  I mean he was not even trying!  I asked him what the minimum requirement was for someone to become a trained listener and he said level 12.  :eek: 

After the event finished, I had all of the dealers come to me and ask me how I did what I did.  They were amazed at it and to them it was like magic.  From then on, and to this day when I run into them at shows, they consider me to have great ears even though I consider myself a failed attempt compared to trained listeners at Harman.

Now, the tables would be turned if we were talking about hearing non-linear distortions.  Again, another story.  

The year is 1998 and I am at Microsoft and was given the audio/video codec team to manage.  I figure I better learn what they are doing and compress some files into 128 kbps MP3.  After some 30 years of being an audiophile I thought it would be a walk in the park to hear artifacts in it.  To my shock and horror, I found the sound to be as good as the CD!  I could not believe the outcome.  Here we had 92% of the file thrown away and the other 8% sounded like the original!  So started a journey to learn not only to hear compression artifacts but also learning to be a "critical listener."  What is a critical listener?  I can look past the music and focus on it as an instrument would.  I can isolate fidelity aspects much like someone lip reading can understand what you are saying without sound.  Slightest changes are important and I know how to find and focus on them.

After some 6 months of non-step trial and error I all of a sudden realized that I could artifacts that others could not.  And I became part and parcel of our signal processing team in evaluating any major changes to our audio algorithms.  Those skills have remained with me and as I mentioned translate to finding small differences that others cannot.

Now you might say why we should care what a few trained listeners can hear.  Well, unfortunately that is not the end of the story, pun intended.  It turns out there are individuals in general public and audiophile circles that have the same critical listening skills.  We were working with one of partner companies that was doing large encoding jobs for our end customers (electronic music distributors).  One of their technical people was complaining about an artifact which we could not hear.  He was local so we invited him to Microsoft.  He comes over with his track and plays it for me and my codec team.  We all look at each other and can't hear any issues.  In amazement, he kept asking, "can't you hear this high-frequency artifact???"  And our answer was no!  

Being an important customer meant that we had to investigate it anyway.  The codec team went to work and actually found and fixed the problem, proving objectively that he was wrong.  And sadly for me, his ears and brain were better than mine.  We hired him right away to work in our codec quality verification team.  

Bringing us full circle, you are absolutely right that the types of distortions we talk about elude vast majority of listeners.  Maybe all but a few.  Having seen so many audiophiles, musicians, professional recording and mastering engineers fail these tests, I am well aware of difficulty of hearing such artifacts.

That is not the topic though.  The topic is what standard bar of fidelity do we set that when we talk to someone else, we are confident they can't hear any artifacts there.  In this instance, you questioned me and as I have demonstrated over and over again during many years, I am able to hear some of these artifacts.  So I sure as heck am not going to brush the problems under the rug.  Seeing how producing quality products doesn't cost much, that is what we need to do as a group. 

What we don't want to do is go around and accuse people as corrupt when we haven't done our homework to understand whether they have the capability to hear things that we may not have.

Finally, let me say that as I have gotten older, I have lost a lot of my high frequency hearing.  So I am probably nowhere as good as I once was.  And others may be able to hear much better than me if they still have their full spectrum hearing.  So let's make sure there is a nice safety margin beyond what I can hear.  Again, it doesn't cost much of anything to do that.


----------



## bigshot (Nov 8, 2017)

The reason I don't have confidence in your reports of your test is because I think you are being disingenuous with us. It has nothing to do with science. If you'd like suggestions on how you might avoid that in the future, I would be happy to provide some.


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## theorist

amirm said:


> Bringing us full circle, you are absolutely right that the types of distortions we talk about elude vast majority of listeners.  Maybe all but a few.  Having seen so many audiophiles, musicians, professional recording and mastering engineers fail these tests, I am well aware of difficulty of hearing such artifacts.



I claim no expertise here on audio science or trained audio listening. Unlike Gregorio or Amirm, indeed, I would probably have difficulty testing correctly above the Harmon band one, if even that, no matter that I have been an audiophile for 40 or so years. But even if I cannot consciously identify that there are distortion artefacts present in the recorded music or play-back system that I am listening to, yet alone what they might be, I suggest that unconsciously I perceive these distorts, at least at their higher levels, so that *this distortion gives me a sense of conscious unease or dissatisfaction* with what I am listening to. That is why I want to listen at least to Red Book standard recordings rather than MP3 and am willing to pay for a four figure DAC over a $29 one, although I never say no to a bargain!


----------



## bigshot (Nov 8, 2017)

If you are subject to unconscious influences, it’s more likely to be bias than it is sound you can’t hear. A controlled blind test could remove that factor and let you know for sure where your subconscious influence is coming from. You might not want to know though


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## JaeYoon

bigshot said:


> If you are subject to unconscious influences, it’s more likely to be bias than it is sound you can’t hear. A controlled blind test could remove that factor and let you know for sure where your subconscious influence is coming from. You might not want to know though


Yeah! Testing from end user is important

another important thing to state is, money does not guarantee distortion free products.
without self-user testing, there is no proof the companies who sell you a four figure dac is outright lying, and also has distortion in their DACs. Let that sink in, IT MIGHT have distortion too. Just because it cost a lot of money, does not guarantee anything.


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## castleofargh

theorist said:


> I claim no expertise here on audio science or trained audio listening. Unlike Gregorio or Amirm, indeed, I would probably have difficulty testing correctly above the Harmon band one, if even that, no matter that I have been an audiophile for 40 or so years. But even if I cannot consciously identify that there are distortion artefacts present in the recorded music or play-back system that I am listening to, yet alone what they might be, I suggest that unconsciously I perceive these distorts, at least at their higher levels, so that *this distortion gives me a sense of conscious unease or dissatisfaction* with what I am listening to. That is why I want to listen at least to Red Book standard recordings rather than MP3 and am willing to pay for a four figure DAC over a $29 one, although I never say no to a bargain!


what I read is that your biases and preconceptions create insecurity which in turn make you uncomfortable until you move up into what you assume to be the more reassuring stuff. it's simple, known and felt by all of us at some point. and it really explains a lot. couldn't you satisfy yourself with that reason? because when I think of some far fetched hypothesis about the subconscious becoming conscious anytime preferences are involved, and conveniently subconscious most of the time a controlled test is involved, I don't see much rational thinking or any evidence telling me to explore that idea. instead I see that it would be pleasing if my preferences were objectively right. and that weird idea would nicely lead to that conclusion. which is IMO more about self gratification and confirmation bias than it is about a plausible hypothesis. 
  I'm not a big fan of Ockham's razor, but in situations like that, it's hard not to think about it. I fear that something won't be enough, so I ruin myself with stress and doubt. and when I remove that cause of doubt in my head, I feel much better. the story or every human being. ^_^


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## RRod

@amirm What were the noise levels in that room?


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## ev13wt (Nov 8, 2017)

amirm said:


> I hear you.  This is one of those things that is hard to believe, i.e. that someone can hear distortions that we ourselves think is an impossibility.  There is fortunately science behind this but one that is not well known outside of industry and research.
> 
> The key here is understanding the concept of a trained listener.  No, I am not talking about self-appointment "golden ears."  I am talking about listeners that have gone through training and verification of their listening ability to be well above general public and that includes audiophiles.  A great published example is that of work for Harman in their loudspeaker research through controlled listening tests.  See this example: http://seanolive.blogspot.com/2008/12/part-2-differences-in-performances-of.html
> 
> ...




Of course, with training and dedication to a certain slice of something, lets stick with "codecs", for 10 hours a day, for multiple years, you should be quite competent at listening.
Being able to tell one codec from another is a piece of cake. (Edit: 1990s)

In real world conditons however...

Don't get me wrong, I basically agree with what you are saying. But to argue benefits to a consumer over those differences is a challenge. They hear more differences in monster cables vs. zip cord and beats by dre vs. included in the box.


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## bigshot

When people try to convince others that they hear "better" than other people, it instantly makes me think that they are looking for ego gratification. I admire people who know a lot about music who can speak about why music expresses what it does and how it is constructed. That is knowledge. Claims of being able to detect harmonic distortion at -90dB and being able to hear frequencies above the capability of redbook require independent objective verification.


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## JaeYoon

bigshot said:


> When people try to convince others that they hear "better" than other people, it instantly makes me think that they are looking for ego gratification. I admire people who know a lot about music who can speak about why music expresses what it does and how it is constructed. That is knowledge. Claims of being able to detect harmonic distortion at -90dB and being able to hear frequencies above the capability of redbook require independent objective verification.


They also must have evolutionary ears beyond a normal human being too.


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## Whazzzup

apple losses cheap and plentiful for me, then get dropped in my flac alias network and stored on my external server ssd roon core as AAC 44.1 16 bit 257 kbps, and is most certainly the largest improvement in sq listening through USB to my TT. so while i may prefer high res some through this same streamer the 16 bit never sounded so good, no complaints.


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## amirm

RRod said:


> @amirm What were the noise levels in that room?


I assume you mean the Harman room.  If so, they have published an AES paper on it:   _A New Reference Listening Room For Consumer, Professional and Automotive Audio Research,_ Sean E. Olive

In there there is this target goal: 

"A Balanced Noise Criterion (NCB) [7] of 10 or
better was the desired target for background noise. In
order to achieve this, a double-shell room design was
employed as illustrated in Fig. 2."

If you are not familiar with NCB ratings, here is a good graph that shows it:






So getting better than NCB-10 means at the threshold of audibility.  Alas, final measurements were not provided at the time of that paper:

"Background noise measurements of the room are still underway and
will hopefully confirm our subjective impressions that
the room is sufficiently quiet for controlled listening
experiments."

Even though I have been in that room multiple times, it has always been with other people there so I can't comment on quiet it was.  

The test in questions by the way don't rely on volume level as they are plenty loud and  you are just listening for tonal changes.


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## RRod

reginalb said:


> Quick question for you, at what level noise floor in a room do you feel that beyond 16-bits would be necessary, and in a normal environment do you feel that noise floor could be simulated with noise cancelling headphones, or CIEMs?



The room for the MM test was at 19dBA, and a difference was audible with a 111dBSPL peak level on this disc. In my listening room at 35dBA at best, that would be a 127dBSPL peak and yeah, not happening.


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## bigshot

A 19dB noise floor would probably be higher if you factor in the noise floor of the blood pumping through the veins in your ear canals.


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## gregorio (Nov 9, 2017)

amirm said:


> Having seen so many audiophiles, musicians, professional recording and mastering engineers fail these tests, I am well aware of difficulty of hearing such artifacts.



This raises a number of issues, largely covered by 1. What we are listening for (trying to identify) and 2. How we are accustomed to listening and making determinations:

1. For example: What musicians tend to listen for is quite different to recording and mastering engineers. Musicians listen for the aspects of performance over which they have direct control/responsibility, the technical performance choices consciously or unavoidably made by the musician/s and the artistic merit of those choices. In this respect they have extremely acute listening abilities, especially as far as their own particular instrument is concerned. Indeed, the difference between what musicians and engineers are listening for is demonstrated by vastly different vocabularies. For example, musicians think in terms of pitch, engineers in terms of frequency and classically trained musicians have a very wide vocabulary (including mainly Italian terminology) to describe aspects of performance/note production/musicality which are of little direct concern to engineers. This is why historically a Producer was required, to effectively to bridge the gap between engineers and musicians. Having trained as a classical musician from my early teenage years, studied in a renown music conservatoire and then been a pro orchestral musician for a number of years, I assumed my listening/analysis abilities would be better than most pro engineers but when I switched over and became a pro engineer myself I found that although my assumption was correct in some respects, there were many other respects/aspects which I was unaware even existed and in those respects my listening/analysis abilities were therefore no better than an average, untrained member of the public.

2. As an engineer, I am accustomed to working/analysing in a certain way. For example, focusing on some effect/artefact, locating the points in the audio file at which that effect/artefact is most obvious, repeating/looping those points, isolating (solo'ing) individual channel/s, making qualitative judgements and adjustments and then pre-rolling the full mix to judge those adjustments in context. That's not how most musicians tend to work/analyse, typically because they do not have the tools to do so.

I downloaded the Harman test, just to see what it was testing and how difficult it was. I only had limited time, did it on my rather old laptop with an old pair of stock Apple ear buds, listened to the first trial of each test and picked 3 of the tests to go further and judge difficulty. Up to and including level 5 I found it easy, picking the correct answer without fail within a couple of seconds or so. At level 6 (with the "Peaks/Dips" test) I did a couple of trials and got the correct answers but I needed more than a few secs, so I stopped at that point. I gave up during level 5 of the "Reverberant" and "Noise" tests, again for time reasons due to the increased number of items to compare.

My observations:
A. Given more time and running the tests in my studio, I think I would probably be struggling at about level 8 and not progress further than level 9, although I'm obviously only guessing at the magnitude of differences between the higher test levels with the noise and reverb tests. Nevertheless, I'm fairly certain I would be unable to reach the minimum Harman requirement of level 12!
B. I'm not at all surprised many musicians failed, going back to point 1 above, some/most of those tests are not really what musicians have trained their hearing to detect. I'm also not surprised that audio engineers failed, at least partially due to the format of the test being so different to how we are accustomed to working/analysing (as explained in point 2 above).
C. I'm sure I would benefit from practising and improving my Harman level but I'm not sure how much. How much time/effort would it take and how much of my improvement would only be in terms of improving my Harman test score, greater familiarity with the test format and songs (where in those songs the various artefacts are most noticeable)? Looking at it another way, if it were possible to create an identical level 12 test with completely different songs, would a Harman "trained listener" still be able to pass or would their level be reduced by their lack of familiarity?
D. Following on from the last point, I'd be interested in the results of some further tests. For example, how would Harman trained listeners' level be affected if they didn't know what they were listening for? IE. A test where the test level could simultaneously be altered for all of the 13 different band and attribute tests but the listener would not know which of those tests her/she was listening to. Without knowing what aspect of the song and which artefact to focus their concentration on, would that trained listener still be able to pass level 12? Another example: If instead of trying to identify which of 12 EQ bands one peak or dip belongs, I wonder how they would do in the same test but with say two or three simultaneous peaks and dips instead of one? Obviously that's a more difficult test but it's possible the gap between Harman trained listeners and audio engineers would be smaller as audio engineers are more accustomed to this sort of scenario.



amirm said:


> The topic is what standard bar of fidelity do we set that when we talk to someone else, we are confident they can't hear any artifacts there.



I'd really like to answer this fully but don't have the time, except to mention one point: Again, there are two sides to this coin. I take it you are aware of the McGurk Effect and that we can easily hear a difference where in fact there is none. Extrapolating this, the "bar of fidelity" could be (erroneously) argued to be infinite, a fact exploited by many audiophile manufacturers. The other side of the coin, there are those who can hear artefacts which exceeding few others can but it requires an entire set of specific conditions. It's also been demonstrated that some people can hear up to about 25kHz but again, only certain people and only under specific (and potentially dangerous) conditions. In real life, how likely are we to find these people AND encounter the required entire set of specific conditions?



theorist said:


> But even if I cannot consciously identify that there are distortion artefacts present in the recorded music or play-back system that I am listening to, yet alone what they might be, I suggest that unconsciously I perceive these distorts, at least at their higher levels, so that *this distortion gives me a sense of conscious unease or dissatisfaction* with what I am listening to. That is why I want to listen at least to Red Book standard recordings rather than MP3 and am willing to pay for a four figure DAC over a $29 one, although I never say no to a bargain!



1. To be aware of something only subconsciously, you still need to be able to hear it! Much of my work is directly in this area, I'm deliberately trying to affect the audience's perception without them being consciously aware of it and the levels we're talking about are very significantly above the thresholds of audibility.
2. As mentioned by others, there is the audiophile myth that more money gets you a better performing product. While that is typically true up to a point, in the audiophile world as the price increases the performance either effectively stays exactly the same or in a surprising number of cases actually gets worse once we get beyond that point and, that point is often significantly lower than audiophiles realise (or are willing to admit)! You yourself, earlier in this thread, posted an example of a $150 USB 2 audiophile cable which actually failed to meet USB 2 specifications.

G


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## theorist

gregorio said:


> You yourself, earlier in this thread, posted an example of a $150 USB 2 audiophile cable which actually failed to meet USB 2 specification


Gregorio, just for the record, I think you are mixing me up with someone else here, as I have made no post about a $150 USB cable that did not make specification, but I take your point.


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## gregorio

theorist said:


> I think you are mixing me up with someone else here ...



Quite possibly, if so, my apologies.

G


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## theorist

gregorio said:


> Quite possibly, if so, my apologies.
> 
> G



No problem, I do enjoy your pragmatic contributions to the threat.


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## Whazzzup (Nov 9, 2017)

What the heck is going on with ferrite cores. I mean you just spent huge doe on dave 14g usd and then 10 g usd on blue 2 and these guys are talking about using 2-18 ferrite cores on a usb cable to make it sound better? I find my server works amazing well and no need for a ferrite at all? I mean you just spent the cost of a medium sedan and need ferrites


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## amirm

gregorio said:


> I'd really like to answer this fully but don't have the time, except to mention one point: Again, there are two sides to this coin. I take it you are aware of the McGurk Effect and that we can easily hear a difference where in fact there is none. Extrapolating this, the "bar of fidelity" could be (erroneously) argued to be infinite, a fact exploited by many audiophile manufacturers. The other side of the coin, there are those who can hear artefacts which exceeding few others can but it requires an entire set of specific conditions. It's also been demonstrated that some people can hear up to about 25kHz but again, only certain people and only under specific (and potentially dangerous) conditions. In real life, how likely are we to find these people AND encounter the required entire set of specific conditions?


When we come to these forums and dispense advice, we have no way of knowing who is reading it.  There is by definition a spectrum of listeners.  Therefore it makes sense for such advice to encompass the population at large.  This is what I call achieving channel transparency.

There is also a second reason for my recommendations: when a device fails to achieve the specs of the silicon they are using, and others can get there with little to no price premium, we need to rally around the companies that do good work.  This is what I call engineering excellence.

You can say you care about one, both or neither.  What I don't have any patience for is to say no one should care for either as Bigtop did.  That doesn't sit right with me.  It is saying let's not give people the information.  To what end I don't still know.  (Actually I do know but it is a darn bad reason).


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## bigshot (Nov 9, 2017)

My name is Bigshot. Why are you so passive aggressive to the people around you? That's no way to become liked and respected.

As I said before. I only care about the quality of the sound human ears can hear for the purposed of listening to recorded music in the home. I totally understand that some people want stereos that far exceed human hearing ability, and that's fine for them. I'm sure there are people who own race cars and only drive the speed limit. But my system has a purpose- and that is to reproduce music. If it does that perfectly for human ears, I'm satisfied and I can move on to focusing on music, not worry about abstract numbers on a page. I reward manufacturers by supporting the ones that make equipment that does the job cleanly, efficiently and inexpensively. I don't need to reward companies for producing sound that no human on earth can hear.

I'm simply stating facts to support a clearly stated logical point of view here. You may not share that point of view, but you can refrain from taking side swipes at me. It doesn't make you look good.


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## castleofargh

different people can have different interests. let's not argue about what people should want.
the only real issue we have here is the amalgam that sometimes can be made between existing differences(as in measurable), against audible differences with the best conditions, best test signal while absolutely focusing on the known issue, against somebody noticing a problem while enjoying a song casually. those 3 are pretty much never similar. more often than not they are several magnitudes apart, so IMO it's important to always be clear about what is being discussed. I personally welcome measurements even if to demonstrate that we shouldn't have to care because of how low they are. information is information and we really can't brag about having too much in amateur audio.  those who don't care just jump to the post after and all is good. 

with USB cables(sorry for going back on topic^_^), I'm afraid that some anecdotal defects and poor testing methods have given many the idea that the magnitudes to expect from changing cables are huge and clearly audible. when IMO if 2 USB cable are audibly different, then one of them is bad, and/or the DAC is bad and the cables just reveal the issue by chance. it's absolutely not right to think about "tuning" the sound with USB cables.
it's certainly not that USB cables cannot create an audible impact, it's that they shouldn't in any normal environment with ok gears. for those sitting on a cellphone tower, maybe special measures are needed, but let's not mistake some extreme circumstances for the norm.


----------



## bigshot

If I was building a recording studio, I would worry about the extremes. But for a portable DAC or DAP or a stereo system in my living room, that sort of stuff is irrelevant. Even if I was building a recording studio, I'd use Monoprice USB cables. Anything above that is just a waste of money.


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## gregorio (Nov 10, 2017)

amirm said:


> [1] When we come to these forums and dispense advice, we have no way of knowing who is reading it.  There is by definition a spectrum of listeners.  Therefore it makes sense for such advice to encompass the population at large.  This is what I call achieving channel transparency.
> [2] There is also a second reason for my recommendations: when a device fails to achieve the specs of the silicon they are using, and others can get there with little to no price premium, we need to rally around the companies that do good work.  This is what I call engineering excellence.
> [3] What I don't have any patience for is to say no one should care for either as Bigtop did.



1. As I see it, what you are suggesting effectively covers not only an extreme situation but a number of simultaneous extreme situations, which are necessary to achieve achieve transparency to the levels you're talking about. How many consumers are trained to the level of a Harman trained listener, how many of those also have an exceptional monitoring equipment/environment in their homes, how many of those who remain are listening to content where such levels of noise is actually achieved and how many of those routinely listen at levels higher than intended? Unless someone is specifically testing for noise levels rather than just listening for entertainment, it's possible that the number of "those" who remain is zero or if there are some, they are certainly outliers. I understand that as an equipment engineer you ideally want to cover all possible eventualities and all the above conditions certainly are possible, just very unlikely. As a content creator I typically have to deliberately ignore "those" remaining people (outliers), because catering to them is often impractical AND undesirable, as it would compromise the enjoyment for everyone else (the target audience).
2. This statement brings us right back to the question I've raised several times, which you refuse to address! I entirely agree with your statement, that with "little to no price premium" it is possible to achieve even your "all encompassing channel transparency" and that we should "rally around" the companies who achieve this "engineering excellence". BUT, what about those companies who achieve that "all encompassing channel transparency" but at vastly higher price premiums, with marketing stating/implying that such a vast price premium is required to achieve such audible transparency, should we also "rally around" these companies or should we not attempt to debunk their marketing and over-charging?
3. I don't see bigshot as saying no one should care. I've had my run-ins with bigshot in the past but he's entitled to say that for him, a DAC beyond say -80dB makes no difference and is therefore not worth caring about. At least he's thought about it, which is more than most do. It's also entirely possible that for the majority (probably even the vast majority) of consumers with their listening skills and usual consumption habits, that he's absolutely right. I prefer to cover more eventualities and feel safer quoting a figure of -100dB or so, while you want to cover all possible eventualities and quote -120dB. All three of us are entitled to these opinions here, as all three of us have justifiable reasoning for those opinions but, each of these opinions also have reasonable counter arguments (except mine of course, because I'm right and you're both wrong!)  

G


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## castleofargh

I thought only mothers were always right? do I need to revise my criteria about truth? ^_^


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## Whazzzup

So no thoughts on this ferrite stuff improving USB. I personally smell something fowl, but won’t knock anyone trying anything.


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## castleofargh

Whazzzup said:


> So no thoughts on this ferrite stuff improving USB. I personally smell something fowl, but won’t knock anyone trying anything.


ferrite has been addressed in this topic and others, and is a simple enough component for you to read its electrical effect and judge for yourself how much it can contribute.  it's a low pass filter of sort, so where it starts rolling off matter more than the ferrite or no ferrite question. but then again black and white views about anything are usually wrong. no reason even for such a simple component to escape the audiophile dumbification of electrical properties.


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## Whazzzup

thx


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## SilverEars (Nov 11, 2017)

Only thing I really care about is the ground loop heard out of my dirty desktop(it's a filth of noise).  I was thinking about getting a usb isolator, but high speed ones are to expensive to be worth it, but also I looked into a usb to opto interface types, and they all seem to be limited in bit rate as well.  I'm looking for cheap options that can go up to 192khz for optical, but unfortunately I don't find them or possibly pricey.  I looked at Monoprice, but hard to navigate to find one.

Not sure if ferrite bead is the solution for this.  I think the most economical option is to get a cheap sound card that has optical out(for some reason, stupids didn't include optical on my motherboard).

I guess either a cheap soundcard or Schiit Wyrd, which does have high bit rate throughput(significantly lower priced than others I've seen for high speed).  Cheap soundcard with optical out, or Wyrd that decraptifies the usb noise?

I think one should listen, and if there is no ground loop heard(anything odd heard), it's fine.


----------



## Darren G

SilverEars said:


> Only thing I really care about is the ground loop heard out of my dirty desktop(it's a filth of noise).  I was thinking about getting a usb isolator, but high speed ones are to expensive to be worth it, but also I looked into a usb to opto interface types, and they all seem to be limited in bit rate as well.  I'm looking for cheap options that can go up to 192khz for optical, but unfortunately I don't find them or possibly pricey.  I looked at Monoprice, but hard to navigate to find one.
> 
> Not sure if ferrite bead is the solution for this.  I think the most economical option is to get a cheap sound card that has optical out(for some reason, stupids didn't include optical on my motherboard).
> 
> ...



There are a couple of of ground loop solutions I've tried.  It is still cheaper to try plugging all equipment into the same ground, but if that is not possible..

The Intona USB solution supports USB 2.0 speeds, and will break a ground loop.  Cheaper solution is the Schitt Eitr, USB in, Coax out.  The former uses optical isolation, the later transformer isolation.


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## SilverEars

I need optical out, not coaxial.  Intona is the one that costs multitude more expensive than Schiit Wyrd for high speed.  Perhaps there is a cheap DIY high speed usb isolator?


----------



## amirm

SilverEars said:


> Not sure if ferrite bead is the solution for this.


Definitely not.  Ferrites increase the impedance of the cable, making it a better high frequency filter.  But for vast majority of them, the effect starts at 1 Mhz (1000 Khz) and above. You have to get pretty fancy to get below 100 Khz so no chance at all that they will do anything with 50 or 60 Hz hum.  Indeed ferrite core manufactures don't even spec what happens below 1 Mhz as this example from Murrata (one of the main manufacturers of magnetic products) shows:







Notice how the x axis starts at 1 Mhz.  The reason manufacturers use them is because of needing to pass regulatory tests.  In this case, "conducted emissions" which start at 1 Mhz  are of concern due to length of the wire acting like an antenna.

The best solution is to use balanced interconnects if you have that option.  If you can't do that, you can use a Jensen transformer.  Or track down the source of ground loop.


----------



## amirm

gregorio said:


> 1. As I see it, what you are suggesting effectively covers not only an extreme situation but a number of simultaneous extreme situations, which are necessary to achieve achieve transparency to the levels you're talking about. How many consumers are trained to the level of a Harman trained listener, how many of those also have an exceptional monitoring equipment/environment in their homes, how many of those who remain are listening to content where such levels of noise is actually achieved and how many of those routinely listen at levels higher than intended? Unless someone is specifically testing for noise levels rather than just listening for entertainment, it's possible that the number of "those" who remain is zero or if there are some, they are certainly outliers. I understand that as an equipment engineer you ideally want to cover all possible eventualities and all the above conditions certainly are possible, just very unlikely. As a content creator I typically have to deliberately ignore "those" remaining people (outliers), because catering to them is often impractical AND undesirable, as it would compromise the enjoyment for everyone else (the target audience).


I already explained all of this.  Refer to how a random person working for one of our partner companies could beat me despite my years of training.  And oh, my testing is done with just my headphones plugged into my HP laptop.  They are nice headphones (Etymotic E4RS IEMs) but nothing exotic.  And that is a key thing: you are in a headphone forum.  Headphones block outside noise exceptionally well and allow one to get to very high levels of listening.  Almost all lossy codec testing is done with headphones for this reason.  So if there are warts, they are far more liable to be heard among the audience of this forum than elsewhere.  Look at how many people complain about noise in amplifiers here vs broader set of audiophiles using speakers.

So there is nothing extreme here.  If I can hear it with ordinary IEMs and a laptop, it is a bar too low.




> 2. This statement brings us right back to the question I've raised several times, which you refuse to address! I entirely agree with your statement, that with "little to no price premium" it is possible to achieve even your "all encompassing channel transparency" and that we should "rally around" the companies who achieve this "engineering excellence". BUT, what about those companies who achieve that "all encompassing channel transparency" but at vastly higher price premiums, with marketing stating/implying that such a vast price premium is required to achieve such audible transparency, should we also "rally around" these companies or should we not attempt to debunk their marketing and over-charging?


The answer to that is continuing to perform independent measurements to see if they are or are not overcharging.  Sitting here, I am disappointed in my purchase of Exasound E32 which retails for $3,500.  See my review here and how I don't suggest people buying it: https://audiosciencereview.com/foru...xasound-e32-dac-review-and-measurements.1990/

We don't get there by what started this argument: that we shouldn't bother measuring.  It is measuring that tells us if we are overcharged for performance or not.  

Heck there are high-end products that actually perform worse.  Again, it is through measurements that we get that information.  



> 3. I don't see bigshot as saying no one should care. I've had my run-ins with bigshot in the past but he's entitled to say that for him, a DAC beyond say -80dB makes no difference and is therefore not worth caring about. At least he's thought about it, which is more than most do. It's also entirely possible that for the majority (probably even the vast majority) of consumers with their listening skills and usual consumption habits, that he's absolutely right. I prefer to cover more eventualities and feel safer quoting a figure of -100dB or so, while you want to cover all possible eventualities and quote -120dB. All three of us are entitled to these opinions here, as all three of us have justifiable reasoning for those opinions but, each of these opinions also have reasonable counter arguments (except mine of course, because I'm right and you're both wrong!)
> 
> G


He didn't just say that.  He said it in response to the work I put in to make these measurements, adding FUD to the data.  He can speak for himself but he has done the opposite here.  I just can't get behind someone who prefers to see less data than more.  And wants to dumb down quality as to win recognition on forums.  I value excellence and execution and the notion that he doesn't care so other should not doesn't sit well with me.  Nor is it a service to the community.  We need to weed out the good and bad.  Then we have data to make an informed decision.


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## bigshot (Nov 11, 2017)

There's no lack of tests and measurements and scientific papers around here. The thing that is lacking the most in audiophile forums is perspective. No one ever puts the specs in the context of listening to music in the home. They point to measurements and listening tests conducted in anechoic chambers with tones as if those are the benchmark needed for a home stereo system. That's totally wrong. The benchmark is REAL human ears in a REAL living room with REAL music. Going to extreme means to extend specs further into the realm of the theoretical is like a big neon arrow with a sign that says "Rabbit Hole This Way ---->". Me pointing that out isn't "dumbing down" anything. It's a hell of a lot more helpful than if I tried to convince people to trust my opinions because I have super human hearing and I work very hard at conducting tests of how equipment performs in extreme theoretical conditions. People want to know what headphones or amp they should buy. That doesn't require splitting atoms. It just requires defining the purpose in which the equipment will be used for to determine how good is good enough. If you want to keep calculating pi out to the 10,000th decimal, feel free to do that. Yes, it's a lot of work. But it isn't helping anyone. Being disingenuous about how you conduct your tests pushes it beyond not being helpful into being distinctly unhelpful.


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## castleofargh

bigshot said:


> There's no lack of tests and measurements and scientific papers around here.


I very much disagree. ^_^


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## bigshot

OK. Now there are a lot of them here. I fixed it!
http://www.aes.org/e-lib/


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## amirm

bigshot said:


> OK. Now there are a lot of them here. I fixed it!
> http://www.aes.org/e-lib/


You have to buy those papers or become a member like I am.  As such, what is there is inaccessible to membership for the most part.  Worse yet, those papers are written for other researchers and engineers in the industry.  As such, understanding them can be quite challenging.


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## amirm

bigshot said:


> There's no lack of tests and measurements and scientific papers around here. The thing that is lacking the most in audiophile forums is perspective. No one ever puts the specs in the context of listening to music in the home.


First of all, these are not "specs" we are talking about.  They are measurements.  Specs are what manufacturers put out, often with no testing to verify them.  

And in those measurements, I absolutely comment on audibility.  Here is an example of Teac NT-503 measurments: https://www.audiosciencereview.com/...asurements-of-teac-nt-503-networked-dac.2028/

"*Listening Tests: Unbalanced Line Out:*
For this test, I used my Stax SRM-007t. I used this because it has dual inputs and allows me to make very fast AB switching. I then used Roon and ganged the NT-503 and Exasound and then NT-503 and Topping into zones. The outcome was synchronized playback on both devices at the same time. Boy do I love Roon! 

Testing first against the Exasound, I could not detect any difference. Both the Exasound E32 and Teac NT-503 produced delightful sound. Gone was what I was hearing with headphones. Alas, the Exasound drivers are quite fragile and just after a few clips, it refused to initialize no matter how many times I restarted Roon, Exasound or plugging and unplugging the USB cable.  The Teac was also flakey until I put it in non-event driven mode in which it became much more reliable So all in all, this testing was cut short but I stand behind the outcome.

Testing against the Topping D30 resulted in tiny preference in favor of Topping D30. Alas, its output is also 1 or 2 db higher and I think that is what I was hearing. Longer term I will do more level matched testing. Outside of that tiny difference, again both were delightful to listen to. Indeed I am doing that as I type this and would be happy with either device playing my reference playlist."​
So perspective is clearly demonstrated yet you keep complaining and talk about issues that are not at all in play here.  Knowing everything I know, when I say something is poorly engineered, it is.  That is data and people need to know that and shift their buying decisions to people who care about creating good performance.  Throwing dust in the eyes of readers and people who work to produce data versus yourself just sitting on the sidelines is not correct. 

From what I have seen, vast majority of these companies have never tested their products with professional measurement equipment.  This is why there are so many surprised in what they produce.  This data needs to get out there as to encourage better designs in the future.  I have already seen companies change their designs and one even discontinue it based on what I have uncovered in my measurements and review.


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## bigshot (Nov 11, 2017)

If a tree falls in the forest and no one can hear it, does it matter if you have a noise floor of -80dB? You keep quoting tests you've done yourself with no oversight, and I've already said that I don't believe that you've been totally honest in your tests. You've already burned that bridge. Get an impartial third party to oversee your tests and I'll listen to results of tests of your hearing ability. For now, I think you've been remarkably disingenuous with us.


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## gregorio

amirm said:


> I already explained all of this. ... my testing is done with just my headphones plugged into my HP laptop. They are nice headphones (Etymotic E4RS IEMs) but nothing exotic. And that is a key thing: you are in a headphone forum. Headphones block outside noise exceptionally well and allow one to get to very high levels of listening. ... So there is nothing extreme here.



And I've also already explained all of this!

In real life, are you really suggesting attaining an exceptionally low noise floor (either with an exceptionally well isolated listening room or using well sealed IEMs in a moderately quiet room) AND playing back at "very high levels"? No, you're talking about testing, about picking quiet passages, maybe even just note decays, which can be safely played at much higher level than normal to expose the noise floor. But of course that is testing, it is not "real life"! In "real life" consumers playback entire tracks, not only the very quietest parts and they do so at a comfortable level. And, what constitutes a comfortable level is relative to the noise floor, so if the noise floor is exceptionally low, the comfortable peak levels are also low. This is the complete OPPOSITE of your testing, which is a very low noise floor AND "very high levels of listening"! If consumers actually applied your test conditions to their everyday listening habits, it could potentially be dangerous/damaging, so how can you reasonably say "nothing extreme here"?

To gain a good idea of the limits of human hearing requires a bunch of at least fairly extreme test conditions. And, I agree it's useful to do such tests and have this information but what I disagree with is calling it something which it obviously is not, "real life"! 



bigshot said:


> There's no lack of tests and measurements and scientific papers around here.



Sorry bigshot, I'm definitely with Amirm on this one. There are a great many claims in the audiophile marketing world and typically either no published measurements/specs at all or only an incomplete list of specs which don't tell the full story of a particular bit of kit's performance, often intentionally! I for one am very thankful for Amirm's work in measuring and publishing the actual performance of consumer kit, regardless of the fact that I disagree with him somewhat about what constitutes the "real life" audibility of artefacts.

The AES, EBU, ITU and others have published a significant amount of tests and measurements of human hearing/perception and generic elements of digital audio but they publish precious little in terms of testing/measuring the performance of specific, individual pieces of consumer audio equipment. So, Amirm is filling an important information hole which is easily accessible by anyone.

G


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## Darren G

SilverEars said:


> I need optical out, not coaxial.  Intona is the one that costs multitude more expensive than Schiit Wyrd for high speed.  Perhaps there is a cheap DIY high speed usb isolator?



For the purpose of breaking a ground loop... note the Schiit Wyrd is just a USB hub, and makes no claims of isolation.  The Schiit Eitr device is the one that provides isolation.  A cheap sound card with optical out is probably your cheapest solution, though depending on your motherboard, there might even be a less expensive option that just exposes the MB headers as Coax and TOSLINK out for < $20.  Some people aren't fans of optical, but that's a different story.


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## bigshot

gregorio said:


> The AES, EBU, ITU and others have published a significant amount of tests and measurements of human hearing/perception and generic elements of digital audio but they publish precious little in terms of testing/measuring the performance of specific, individual pieces of consumer audio equipment. So, Amirm is filling an important information hole which is easily accessible by anyone.



I don't think I trust his findings any more than I do the manufacturers' sales sheets. AES at least has peer review and hopefully they have oversight to make sure things aren't fudged to make a point.

It's really easy to do basic listening tests to find out if a piece of equipment achieves audible transparency. I do that with every piece of equipment I buy. If everyone did a simple controlled listening test to compare their equipment, the problem of coloration would be solved. However, I really don't think that is a very big problem. Every time I ask someone who argues that colored equipment exists to point out an example, they either point to high end stuff that has been deliberately colored and everyone knows it, or they point to a $20 DAC that's only noisy if you have bats' ears and can hear noise floors under -80dB. I have a $40 Walmart DVD player that is audibly transparent. Every computer I've ever owned going back to 1995 has been audibly transparent. Every DAP, every DAC, every player I've ever bought is audibly transparent. I don't think I'm doing anything special selecting these. It really isn't hard at all to find stuff that performs perfectly for human ears. Now transducers are a different story... But with transducers, you almost have to assume that they are going to be colored and apply room treatment and EQ to pull them into line. I find the headphones response curves published by various people on HeadFi to be very valuable. I think most of the discussion here about amps, DACs and players to be full of hot air. Even the people doing the testing don't seem to know that the numbers they call "horrible" are thoroughly inaudible. That doesn't instill confidence in me to the value of their testing.


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## amirm (Nov 12, 2017)

bigshot said:


> I don't think I trust his findings any more than I do the manufacturers' sales sheets. AES at least has peer review and hopefully they have oversight to make sure things aren't fudged to make a point.


First of all, you are completely wrong about peer review of Journal of AES.  There is absolutely nothing in the peer review that vouches for either correctness or authenticity of the data in a paper.  Nothing.  My team at Microsoft was routinely in peer review loop of major organizations and that is absolutely how it works.

What the peer review does is to catch fundamental mistakes with respect to science or as my PhD researchers would say, "something they taught you in college."  If for example you didn't know what a fourier transform was, you get called on it.  But if you ran a blind test and are reporting the results, as long as you don't outline protocol errors, the outcome whatever it is, will not get subjected to any review or correction.  No peer review agency can ever do that as they would have to try to duplicate the experiments which simply is not practical.  They will refuse however to accept non-scientific work like sighted listening tests, etc.

So you can definitely "fudge" what you submit to AES.  If you do, and someone re-runs the test and disproves what you have, you will be embarrassed and that is the guard against pulling such stunts.  Same is true here seeing how I post under my real name and everyone from my family to friends, customers and professional colleagues read them. You might play fast and loose with your posts here but I don't have that luxury, nor is anything said here is worth the ethical misconduct.

What is really going to get you is that there is published, peer reviewed, AES paper that shows audibility of resampling high-resolution audio to CD rate.  See: 



In there they report on results of double blind tests showing audibility of digital filters to resample audio to lower rates:




Here is the statistical summary results, with the dashed line the threshold for 95% confidence (p < .05):




(Don't be confused about the percentage numbers on the left.  See this article I wrote on that: https://audiosciencereview.com/forum/index.php?threads/statistics-of-abx-testing.170/).

I assume you have not read the paper.  In that case, you can read my digest of it which was *published* in the Widescreen Review Magazine here: https://audiosciencereview.com/forum/index.php?threads/high-resolution-audio-does-it-matter.11/

So there it is: peer reviewed, published study using real music and with speakers, saying what you say is impossible.  Or must be a lie.

As I noted above, ton of my work and measurements has been published for the world to see including some of the major detractors.  They have stood the test of time because they are credible and not isolated experiences.

You don't like them because it goes against what you have learned to repeat online.  So you are trying to protect your back side by crying "liar, liar."

Time permitting, I will repeat one of these tests, take a video of it, post i there and then show you how you too can hear the difference.  Or at least some readers can.


​


----------



## amirm

bigshot said:


> If a tree falls in the forest and no one can hear it, does it matter if you have a noise floor of -80dB?


My reel to reel tape deck has 80 db signal to noise ratio and its tape hiss is definitely audible.  Do you really have trouble hearing such a noise floor?

We got digital as to be free of such noises.  The silicon DAC box makers use is easily capable of providing far, far better performance.  But when it is stuck in a box without competence, much of that headroom is lost.  

Here is a fresh of the press review and measurement of a $450 digital audio player, the Shozy Alien+:  https://www.audiosciencereview.com/...of-shozy-alien-digital-audio-player-dap.2058/

Here is how it does against my Samsung S8+ cell phone:






Without this data if I polled 10 audiophiles which one has better performance they would ay the Alien+.  Yet in test after test, it underperformed both my laptop and Samsung s8+. 

The AKM DAC in there is capable of far better performance.  Poor design choices cause substantially higher noise floor.  I like to shine a light on these issues as to weed them out.  There is no reason whatsoever to live with -80 db in digital age and in this year and decade.

80 db... Why don't we bring back horse and buggy while we are it????


----------



## Arpiben

Whazzzup said:


> So no thoughts on this ferrite stuff improving USB. I personally smell something fowl, but won’t knock anyone trying anything.



If you are interested in EMI and noise supression, you may have a look at those Murata`s papers:
https://www.murata.com/en-eu/products/emc/emifil/knowhow/basic


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## bigshot (Nov 13, 2017)

amirm said:


> My reel to reel tape deck has 80 db signal to noise ratio and its tape hiss is definitely audible.



With analogue tape, the noise floor depends on the tape speed and how hot you burn the signal into the tape. At 15ips at a good level, I generally can't hear tape hiss at normal listening volumes. It's perfectly fine. It's also quite listenable at 7 1/2 ips. Tape hiss is usually only audible in the dead spots between songs. But when I worked on tape, that was usually leadered up anyway. Analogue is capable of producing excellent high fidelity sound... it's just more work to maintain it because analogue has generation loss, so noise tends to stack up.


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## GrussGott (Dec 21, 2017)

Having read the first 9 pages of this thread - which I would sum up as _"I have selected a few facts and now believe I fully understand all audio and electronic phenomena and anyone who questions the finality of my conclusions must be delusional"*_-   so this seems like one of the worst threads on the site so I thought it'd be a good idea for me throw out my 2 cents.  Which probably has already been said somewhere in these pages already.

(1.) If it sounds better, then delusion or not I'm fer it
(2.) if it sounds like blowhards pissing then I'm agin it
(3.) I bought an Eitr and it sounds WAY better than without or via my optical input from my MBP

The fact is, I don't know what's in that Eitr box.  Could be well designed electronics doing good ear stuff or it could be a box of delusions or it could be machine elves.  It really doesn't matter to me because it works and there is science to explain why that is, it's just that either nobody here or no humans know what it is.

Some engineers at Cisco who design audio gear think USB cables make a difference because they scienced it out.  There are also a few Google engineers (from both legacy tanberg and android) who say the same thing for the same reasons and have posted stuff somewhere.  Could be the bathroom for all I know - they post a lot of sciencey stuff above the urinals.

Anyway, it's something about chip sets and noise backing the chips up and the audio protocol doesn't ask for missed bits so filters have to fill in gaps and this causes audio quality degradation blah blah blah.

The Eitr is a pretty sweet product that can help listening be better, is my point.


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## D2Girls

GrussGott said:


> Having read the first 9 pages of this thread - which I would sum up as _"I have selected a few facts and now believe I fully understand all audio and electronic phenomena and anyone who questions the finality of my conclusions must be delusional"*_-   so this seems like one of the worst threads on the site so I thought it'd be a good idea for me throw out my 2 cents.  Which probably has already been said somewhere in these pages already.
> 
> (1.) If it sounds better, then delusion or not I'm fer it
> (2.) if it sounds like blowhards pissing then I'm agin it
> ...


Haven't you heard, usb5 board from schiit audio is product of the year?


----------



## gregorio

GrussGott said:


> (1.) If it sounds better, then delusion or not I'm fer it
> [2] It really doesn't matter to me because it works and there is science to explain why that is, it's just that either nobody here or no humans know what it is.
> [3] Some engineers at Cisco who design audio gear think USB cables make a difference because they scienced it out.  There are also a few Google engineers (from both legacy tanberg and android) who say the same thing for the same reasons and have posted stuff somewhere.



1. That's your choice of course but IMO it's a poor choice. The problem with delusion is that just one simple piece of information, one new bias or one somewhat changed bias is all it takes to change or even completely dispel that delusion. So your "fer" spending money for something which "sounds better" for maybe just one instant or however long it takes for your perception biases to change? Personally, if I spend decent money on something I want better sound for longer than one instant, I want to know that I'm actually getter better sound and therefore whatever my biased perception is attempting to tell me from instant to instant, day to day can be dismissed as just a temporary delusion.
2. Recording and reproduction technology is made by humans, according to the science known by humans. Whether or not there is something that science doesn't know or that humans don't know is irrelevant because we can only record what we know and can measure. If we don't know and can't measure something then we cannot record it and it doesn't exist on any of the recordings to which you are listening!
3. I don't think anyone here is stating that USB cables don't make any difference, that's NOT what we're questioning. What we're questioning is if those differences are audible and if so why. The answer to this question is generally "no" but could potentially be "yes" if the DAC is effectively faulty. Your Eitr appears to be an example of the latter, a fix for a faulty DAC. If it were me, I would've returned the faulty DAC and demanded the manufacturer fix it at their expense or give me my money back. The VERY LAST thing I'd have done is spend another $180 with that company to fix their faulty device ...  but that's just me, maybe that means I'm not a true audiophile/audiophool?

G


----------



## castleofargh

GrussGott said:


> Having read the first 9 pages of this thread - which I would sum up as _"I have selected a few facts and now believe I fully understand all audio and electronic phenomena and anyone who questions the finality of my conclusions must be delusional"*_-   so this seems like one of the worst threads on the site so I thought it'd be a good idea for me throw out my 2 cents.  Which probably has already been said somewhere in these pages already.
> 
> (1.) If it sounds better, then delusion or not I'm fer it
> (2.) if it sounds like blowhards pissing then I'm agin it
> ...


while your summarized quote does indeed fit with too many posts on both sides of the argument, what you do after is another emblematic aspect of going nowhere. 
your points (1.) and (2.) are saying that you follow your personal feelings no matter what is really going on.  ok, so? at the end of the day we all do whatever we want with our ears. it's not the "how should I feel?" topic, we assume that you're going to do that just fine on your own. but here is an objective topic on how, how much, and why a USB cable can change something in the playback chain.  so dismissing objective data means you have no interest in the topic. 
then in  (3.) you want us all to know that you're happy with some magic box you bought. again, I believe we have appreciation threads for that kind of stuff. what's more, maybe it will come at as a shock, but it isn't a USB cable. ^_^

then you proceed without really saying anything about how some people say stuff somewhere. we would prefer links or quotes with any data backing it up. then we could get somewhere.


----------



## GrussGott

gregorio said:


> The answer to this question is generally "no" but could potentially be "yes" if the DAC is effectively faulty. Your Eitr appears to be an example of the latter, a fix for a faulty DAC. If it were me, I would've returned the faulty DAC and demanded the manufacturer fix it at their expense or give me my money back. The VERY LAST thing I'd have done is spend another $180 with that company to fix their faulty device ...  but that's just me, maybe that means I'm not a true audiophile/audiophool?



 You're hilarious!  If you actually want to know the science - and not just entertain us all with these posts - then interview some internetworking engineers who design USB connected audio products for a living - they have plenty of science-y stuff, but the answer to the question the thread asks is noise on the line overwhelms the receiver chip sets.  Also, FYI, unless we're talking optical all cables are analog because electricity / conductor.

But seriously - it would be trivially easy for you to get time in a lab at Google or Cisco; just show them three of your most certain posts.  They'll spend HOURS with you.


----------



## amirm

GrussGott said:


> (1.) If it sounds better, then delusion or not I'm fer it


The problem with that is if it is a false conclusion, the effect wears off.  Have you noticed how often some folks go through audio tweaks?  From one footer to another.  From one cable to another.  



> The fact is, I don't know what's in that Eitr box.  Could be well designed electronics doing good ear stuff or it could be a box of delusions or it could be machine elves.


Well, I do.  They advertise that all of their products are manufactured in US.  That is actually false in this case.  I have it on *solid authority *that they actually manufacture them by virgins on some tropical island (waterboarding was insufficient to get the name of said island from my contact).  They apparently soak the component from juice of special variety of guava fruit juice that adds certain amount of sweetness to the sound.  So there is no mystery there.  If I had that juice I too could make all of my audio gear sound better.

And folks sad there is nothing but useless commentary in this thread!!!


----------



## Strangelove424

Does anybody in this thread have actual noise issues with USB? There's something I'd like to test. Just requires honesty, any USB cable, and black tape. No permanent change to cable. Must have noise present before hand. Thanks.


----------



## gregorio

GrussGott said:


> .. [1] but the answer to the question the thread asks is noise on the line overwhelms the receiver chip sets.
> [2] Also, FYI, unless we're talking optical all cables are analog because electricity / conductor..



1. So, they've designed their DACs with faulty receiver chip sets then. Or are you saying that all USB receiver chip sets are overwhelmed by noise and therefore the USB protocol never works?
2. Analog, seriously? Do you know what analog means or do you actually buy recordings of nothing but square waves in the megahertz range? 

Hilarious indeed!

G


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## GrussGott (Dec 21, 2017)

Strangelove424 said:


> Does anybody in this thread have actual noise issues with USB? There's something I'd like to test. Just requires honesty, any USB cable, and black tape. No permanent change to cable. Must have noise present before hand. Thanks.



It depends on what you mean by "noise".  For me, I tested cables and such with my wife who doesn't know nor care nor have any idea what any of this stuff is.  I basically switched cables around over and over, swapped in boxes like the Eitr, and swapped out dacs like mimby vs mojo.  she was a good sport and her observations were very similar to mine.  macbook pro >  tidal hifi exclusive mode > [cables] > [magic box or not] > dacs > schitt jot > HD600 of TH-x00

*Net-net: 
USB Cables:* anker powerline+ vs Pangea  Premier vs some cable that came with our printer: not much difference if any, granted none of these are spendy cables
*TOSLINK vs USB:* USB wins or no difference, i.e., on songs with a win, USB won
*Eitr vs no Eitr:* unambiguous win no matter the song or cable

So by "noise" does that mean you can audibly hear clipping or simply lower resolution that's only discernible when you listen to same source same song which sounds more "crisp", others may call it "resolving"?

BTW, in a surprise, there seemed to be something to plugging the Jot into a wall outlet with a 14awg high quality power cable versus the 18awg cheapie it came with into a surge protector and then into the wall


----------



## amirm

Strangelove424 said:


> Does anybody in this thread have actual noise issues with USB? There's something I'd like to test.


Well, my son did with the Schiit BiFrost.  He an internal card before that and when playing games, he could hear the activities of the computer through his headphone.  He bought the Schiit BiFrost for $400 only to find the same issue.  I put it on the bench and indeed, depending on what the computer was doing, its output would change!  You can read the story here: https://audiosciencereview.com/foru...puter-activity-can-impact-dac-performance.22/

So objective measurements confirmed his subjective experience.  But only in the case of poorly designed DACs of which there are very few.  Even China Inc is making DACs for peanuts that have inaudible PC/USB related noise.

To the extent we can continue to measure products that come to market, we can weed out hopefully the bad apples.


----------



## GrussGott

gregorio said:


> 1. So, they've designed their DACs with faulty receiver chip sets then. Or are you saying that all USB receiver chip sets are overwhelmed by noise and therefore the USB protocol never works?
> 2. Analog, seriously? Do you know what analog means or do you actually buy recordings of nothing but square waves in the megahertz range?



That sounds pretty cool.

Hey, 'member when we did this game backwards??

AUDIO was the digital!


----------



## Strangelove424 (Dec 21, 2017)

amirm said:


> Well, my son did with the Schiit BiFrost.  He an internal card before that and when playing games, he could hear the activities of the computer through his headphone.  He bought the Schiit BiFrost for $400 only to find the same issue.  I put it on the bench and indeed, depending on what the computer was doing, its output would change!  You can read the story here: https://audiosciencereview.com/foru...puter-activity-can-impact-dac-performance.22/
> 
> So objective measurements confirmed his subjective experience.  But only in the case of poorly designed DACs of which there are very few.  Even China Inc is making DACs for peanuts that have inaudible PC/USB related noise.
> 
> To the extent we can continue to measure products that come to market, we can weed out hopefully the bad apples.



Thanks Amirm. I was wondering if perhaps these noise issues come from noisy grounds (completely unrelated to cable quality) and that perhaps by blocking off the GND connector with electrical tape might be a cheap fix. Does the Bitfrost need the USB's 5v power? If not, perhaps you could block off the 5v connector too, if that might be a source of noise as well. I am trying to isolate the cause of what may be giving certain people EMI headaches but it could be as simple as USB ground loops, which is not the fault of any particular cable or device but a conflict of ground between multiple devices. Even motherboard i/o for USB are often serialized, so direct connection is no guarantee of unshared power. You can use the most expensive cables in the world, it will still happen. Would be great to be able to suggest to people a solution as cheap and effective as black tape. I'd appreciate if you could experiment with the idea.

Edit: NM, just read your conclusion of sending the DAC back. I guess it's not available to test anymore. For $400 I wouldn't keep it either.


----------



## D2Girls

Strangelove424 said:


> Does anybody in this thread have actual noise issues with USB? There's something I'd like to test. Just requires honesty, any USB cable, and black tape. No permanent change to cable. Must have noise present before hand. Thanks.


coax input on my dac sounds better than usb input thats all i can say about that
i would like to try the aes input but i dont have a digital source with one


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## Strangelove424

Not looking for "sounds better", need audible or better yet as Amirm showed measured interference or ground loop noise. This is a specific problem.


----------



## GrussGott

amirm said:


> Well, my son did with the Schiit BiFrost.  ... only in the case of poorly designed DACs of which there are very few.



Curious is you ever contacted jason or mike given they're on this forum with this data and got a response?


----------



## amirm

GrussGott said:


> Curious is you ever contacted jason or mike given they're on this forum with this data and got a response?


They have seen the latest measurements I made of Schiit Modi 2.  Start reading from this post on: https://audiosciencereview.com/foru...eview-schiit-modi-2-99.1649/page-8#post-57393 
They have made no attempt to contact me at all.

It is not like the DAC is actually broken so I am not sure why you are asking me to contact them.  It works as a DAC and that is what I paid to buy.  That it doesn't perform is shame on me and the rest of the population that buys it blind without such measurements from the manufacturer.

As for my Son's Schiit DAC, he wrote to them why he was returning it and all they did was give him the RMA number to do so.  Which he did.


----------



## GrussGott

amirm said:


> As for my Son's Schiit DAC, he wrote to them why he was returning it and all they did was give him the RMA number to do so.  Which he did.



So what did he replace it with?


----------



## amirm

GrussGott said:


> So what did he replace it with?


First he went with a $1000 Peachtree.  Alas, that was clipping on some of his music due to overflow in their resampler.  So he bought an Oppo HA-1 which was similar price (this is 2 to 3 years ago).  Alas, the optical encoder has gone bad on that and I have been trying to fix it for him.  And even when it was working, it would not track well at low levels.  It performed well for him otherwise.


----------



## GrussGott

amirm said:


> First he went with a $1000 Peachtree.  Alas, that was clipping on some of his music due to overflow in their resampler.  So he bought an Oppo HA-1 which was similar price (this is 2 to 3 years ago).  Alas, the optical encoder has gone bad on that and I have been trying to fix it for him.  And even when it was working, it would not track well at low levels.  It performed well for him otherwise.



So attempting to stay on topic and being a fan ...

(a.) clearly there's disagreement on why a 'good' USB cable "sounds better" and some might say it doesn't or can't
(b.) some might also say that if the DAC is well designed, then the cable is mostly irrelevant (and if not, the "better sound" might be due to lack of DAC performance consistency)
(c.) Thus some may conclude that best way to have a good USB cable is to have a good DAC (i.e., well designed)

So if we picked 4 price points of DACs which will give you good USB cable performance, how would you fill in the blanks?

$50-$300 - ?
$300- $500 - ?
$500-$750 - ?
$750-$1000 - ?

And finally, if we were going to be sciency about it (assuming my a,b,c is agreed to), then we'd test various USB cables going into those DACs versus a "poorly designed" one and show that the output of the well designed DACs equalizes the USB cable performance.

Or else I'm not understand anything you're saying.  Which is the more probable answer.  But I'm taking a shot.


----------



## bigshot

GrussGott said:


> I tested cables and such with my wife who doesn't know nor care nor have any idea what any of this stuff is.



SKOLL! The Sound Science drinking game says every time we get an "even my wife can hear it" story we have to drink a beer!

I have an HA-1 and Oppo PM-1s. I compared the output of an AIFF file playing on my iMac through normal headphone out to the output of the same file through the HA-1 and couldn't hear any difference. I was going to use the HA-1 with my iMac, but there isn't much point. I'm trying to think of a use for the HA-1, but it just sits on my bedstand unused right now.


----------



## amirm

GrussGott said:


> So if we picked 4 price points of DACs which will give you good USB cable performance, how would you fill in the blanks?
> 
> $50-$300 - ?
> $300- $500 - ?
> ...


I have tested 10 to 15 DACs so far.  I will need to test a lot more to fill that table properly. So ask me again in about a year  

Lots of my focus has been in lowest cost category.  There ($50 to $300) my clear pick is the Topping D30. At $130 it does a lot of things right.  The company also is one of the few that measures its gear just like I do so no surprise that they release it when it performs.


----------



## amirm

GrussGott said:


> And finally, if we were going to be sciency about it (assuming my a,b,c is agreed to), then we'd test various USB cables going into those DACs versus a "poorly designed" one and show that the output of the well designed DACs equalizes the USB cable performance.


I have done one pass of such tests (see https://audiosciencereview.com/forum/index.php?threads/do-usb-audio-cables-make-a-difference.1887/), and the conclusion there was that the type of cable did not matter.  What mattered (slightly) was the length of USB cable.  If you want to do better there, just use as short of the cable as you can.  For my testing now I try to use a 1 foot cable when I can for that reason.  Mind you, it is not an audible consideration but it is one of those "might as well" things.  

I am happy to re-run this test at a future date but need more audiophile USB cable samples.  I have had two on loan (one that is returned now) and so the sample size is too small.

Alternatively if the cables don't cost an arm and a leg, I can buy more of them to test.  But I really rather put the funds towards more real products like DACs and such than more cable testing.


----------



## GrussGott

amirm said:


> I have done one pass of such tests (see https://audiosciencereview.com/forum/index.php?threads/do-usb-audio-cables-make-a-difference.1887/), and the conclusion there was that the type of cable did not matter.  What mattered (slightly) was the length of USB cable.   Alternatively if the cables don't cost an arm and a leg, I can buy more of them to test.  But I really rather put the funds towards more real products like DACs and such than more cable testing.


Much appreciated for the insights Amir - I'd love to see this kind of thing continued because ...


bigshot said:


> SKOLL! The Sound Science drinking game says every time we get an "even my wife can hear it" story we have to drink a beer!



The bummer with this hobby is that it's so full of blowhards, dinks, schills, and arseholes, that any topic creates two camps with the loudest arseholes carrying the flags.

I suppose that's inevitable as it's a niche hobby and those are gathering points for the insecure ... nevertheless there's no getting around a fact: the hobby is part objective and part subjective.

Everytime we get a legit question like USB cables (one component of a complex system) some wee-schlong shows up claiming to have definitive answers; as if that's even possible.

Instead let's ask good questions, collect anecdotes, leverage tests, and see if we all can't contribute to a collective analysis without resorting to resume trumpeting and name calling.

I think Amir is really helping move us along - he hasn't been treated fairly in some places, but then neither have they.

Wouldn't it be great if we could all set that aside and focus on the question?

Amir, any and all DAC/USB analysis in your $50-$300 range is greatly appreciated.


----------



## bigshot

This forum is regularly invaded by blowhards and dinks who want to foist their subjective impressions on us just because they know we won't like it. Stick around and you'll witness the waves of audiophool trolls for yourself.


----------



## Glenn Adema

I know they do make a huge difference... Can only and simply say.. Just replace a copper usb/spif or interconnect or speaker cable with a silver one and you will be a believer.. However the unbelievers love to shout as there is no proof given in tests which for them is enough to claim this..  Fortunately some audio lovers experience things for themselves before believing and hey.. If you buy or borrow a silver cable you can always bring it back..  Discussion closed.


----------



## castleofargh

Glenn Adema said:


> I know they do make a huge difference... Can only and simply say.. Just replace a copper usb/spif or interconnect or speaker cable with a silver one and you will be a believer.. However the unbelievers love to shout as there is no proof given in tests which for them is enough to claim this..  Fortunately some audio lovers experience things for themselves before believing and hey.. If you buy or borrow a silver cable you can always bring it back..  Discussion closed.



the lack of proof is the reason *not* to make claims. you do it wrong with your empty claim, then explain it wrong.
it's also important not to throw all cable types in the same bag like you do. this is a USB cable topic, not troll fiesta special. 

 for a first post, I'm not going to lie, it's bad. if skepticism troubles you, and you really don't get why when a test doesn't prove what you want, you shouldn't go claim it's real anyway, then I invite you to go make your cable preaching there: https://head-fi.org/forums/cables-power-tweaks-speakers-accessories-dbt-free-forum.21/ it's a DBT and ABX free sub section, much more appropriate for your post.  in this "sound science" sub section we care about objective evidence to decide that something is happening or not. or listening tests but only when they are controlled enough so that we can put some level of trust in the results. and then we try to determine if our anecdote which is usually what an individual gets when testing his gear, may relate to more than that one anecdote. maybe not your cup of tea and that's alright, this is why the forum has various sections. so people can discuss in the appropriate one for them.


----------



## bigshot

This is probably a fake account. Newly created. One post tossing a lit torch into Sound Science. If you can do an IP check, you'll probably find that it's a regular poster on HeadFi with another account. (and an axe to grind.)


----------



## GrussGott

castleofargh said:


> in this "sound science" sub section we care about objective evidence to decide that something is happening or not. or listening tests but only when they are controlled enough so that we can put some level of trust in the results.



I would argue that you either didn't well articulate or don't understand skepticism and science: Enough people experience the phenomenon for us to conclude some is happening - that's settled.  What we need to skeptical about is any given explanation.  For example, Newton's Law of Gravity doesn't fully explain gravity, and we can be skeptical that he's fully modeled gravity, but it doesn't mean we don't all experience gravity.  Further, while Einstein's general theory of relatively most accurately explains gravity, we still don't know the cause ... but we all still experience gravity.

In short, the phenomenon is real, it's the explanation we should be looking for.


----------



## old tech

Some of the more recent discussion is so far removed from sound science that it is questionable why this thread isn't sent back to where it originated.

The article in the link below presents good information on why this topic is audio woo.

https://rationalwiki.org/wiki/Audio_woo


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## bigshot (Jan 5, 2018)

GrussGott said:


> Enough people experience the phenomenon for us to conclude some is happening - that's settled.



Then the existence of fairies and shadow people and slender man are settled too. Thanks for settling that for us!

http://www.softschools.com/examples/fallacies/bandwagon_examples/488/
https://rationalwiki.org/wiki/Science_doesn't_know_everything


----------



## Don Hills

GrussGott said:


> ... In short, the phenomenon is real, it's the explanation we should be looking for.



In this particular section of Head-Fi we start with the most likely explanation, being the already proven phenomenon of people believing they hear an audible difference when there is no actual difference. If you wish to argue otherwise, you need to  provide falsifiable evidence to prove your argument.


----------



## gregorio (Jan 5, 2018)

Glenn Adema said:


> I know they do make a huge difference... Fortunately some audio lovers experience things for themselves before believing and hey.



You are confusing "experiencing" with "knowing".



GrussGott said:


> Enough people experience the phenomenon for us to conclude some is happening - that's settled.  ... In short, the phenomenon is real, it's the explanation we should be looking for.



You appear to be doing the same! Just because "enough people experience" something does NOT make it a "real" phenomenon. As bigshot stated, the consequences of such a correlation fallacy is that you logically have to believe in ghosts, magic, a flat earth, that there are no aural or visual illusions only real phenomena, plus any number of other things some people have experienced  AND you have to discard logic, the obvious, provable demonstrations that experiencing and real phenomena do not necessarily correlate and indeed the reason why modern science was developed in the first place!

G


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## bigshot (Jan 5, 2018)

Has anyone noticed that these folks come in pairs? Just like socks.



GrussGott said:


> I think Amir is really helping move us along - he hasn't been treated fairly in some places, but then neither have they.



Who are "they" and how has Amir been treated unfairly in some places?


----------



## castleofargh

GrussGott said:


> I would argue that you either didn't well articulate or don't understand skepticism and science: Enough people experience the phenomenon for us to conclude some is happening - that's settled.  What we need to skeptical about is any given explanation.  For example, Newton's Law of Gravity doesn't fully explain gravity, and we can be skeptical that he's fully modeled gravity, but it doesn't mean we don't all experience gravity.  Further, while Einstein's general theory of relatively most accurately explains gravity, we still don't know the cause ... but we all still experience gravity.
> 
> In short, the phenomenon is real, it's the explanation we should be looking for.


you're going too fast. you believe we have evidence, but where? on this topic? I've seen a few measurements telling me I wouldn't notice the stuff they were looking at in my normal listening of music. I have my own tests(admittedly only with USB cables for normies) where I tried a bunch of things from less than ideal blind test, to less than ideal measurements. and aside from a defective cable, and one that was specific for charging a high power stuff and clearly didn't have the usual electrical specs(very different impedance and such), I didn't get anything telling me I should bother with USB cables for my music. 
on the other hand, I have all of human history to demonstrate how easily people can be fooled into believing things that aren't there.
so about 


GrussGott said:


> Enough people experience the phenomenon for us to conclude some is happening - that's settled.


I'd say I'm really not here yet. vague feedback from vague experiments are never going to be conclusive. sighted tests with close to zero controls and not even a reliable way to tell that what the guy feels comes from sound, that's very vague and I'd only settle on not trusting such feedback even from myself. so from dudes on the web... no thank you very much. skepticism here is just common sense really.
it all comes down to placing the right amount of confidence on ideas, experiences and the conclusion we draw from them. but for that to be done, we need to have clear ideas, and *clear experiences*, or we're really just wasting time. nobody is going to be able to prove or disprove a vague thing. which in turn should be the signal that we cannot make claims about it(you know that old tradition of claiming stuff after we have evidence of it, instead of before ^_^). but most audiophiles seem to be missing that signal. maybe because of ignorance, too much ego, the need to gloat, or just the need to try and justify spending a fortune on cables that may or may not do exactly the same thing as a 15$ one... IDK. but they do a lot of claiming based on gut feelings and one off anecdotes. 2 elements I don't remember seeing mentioned as highly conclusive in the scientific method.

 maybe sometimes, 2 cables under some circumstances end up making a huge audible difference. but so far, people really sucked at documenting such events. so not only don't we know that the conditions were standard, most of the time we can't even know if it happened or if some guy just went full on placebo. so no it's not settled. 
but later when/if we get evidence that basic usb cable is in general not good enough for audio, we'll be able to move on to other questions like "why", or "how do you check that a cable is better than another one?". we just aren't there yet despite the loaded title of the topic.


----------



## amirm

GrussGott said:


> In short, the phenomenon is real, it's the explanation we should be looking for.


Oh, we have a very clear and provable explanation for why people report improvements in fidelity with these cables.  The answer lies in the way we experience things.  Our impression of fidelity is formed by many factors, with sound just being one factor.  To wit, we can run experiments where A and B are identical yet listeners report them as having differing fidelity.  In that regard, there is no sense in chasing the unknown.  We know a priori that sound waves did not change.

In other words, the experimental protocol that people use is the problem.  Once you have a faulty experiment, you can't assume the data is valid and then look for a real explanation.

If we had proper test results that showed real audible differences then I for one would be happy to look for the right explanation for it.  

Indeed this inability to run proper tests in audio has led to any and all things being valid.  No matter how useless a device I can guarantee that there will be people who "hear improvements.  You give me anything, a pencil, a rock, a thumb tack, anything at all and I can run experiments with audiophiles that indicates it has a sonic improvement.  Surely logic would indicate that there are some things that make no difference at all.  Yet the type of experiments we run as audiophiles doesn't allow for that.


----------



## Glenn Adema

First let me say im not a fake account or anything.. Just replied incorrect in the wrong section as im new on headfi. However, as a sys admin for 19 years I know what frustrate people with these kind of claims. We claim it for ourselves but since there is no proof whatsoever we shouldnt post it to an audience in this way. I personally do think that as long as there is no science to proof that different usb cables do sound different, the only thing we do have that is relevant is feeling, however feelings and rational claims often dont go well together. Some of us hear differences, enjoy music better with a specific type of cable, yes we think and feel we do. Furtermore we as a group also feel we are sane and want to response when others say we are not. Also when we enjoy music more due to a specific cable (we think we do), we start to feel better etc. Then we want to share our finding as we think it makes our lives better and for some reason we care about others. I think thats summons most of it. As for music, feelings are all that matter. Its far from rational and maybe not right in this section but as no one has any proof that it does sound better it simple doesn't sound better in a rational matter (as there are many test that summarizes with 'no changes detected'). To say that it does doesnt make any sense without further commenting. Fully agree on this.. Again The stupid thing with music is that it isnt rational. Therefore its impossible to post anything on this matter as there will always be 2 camps. Camp 1 that cannot hear any difference nor find good solid tests that might get them to reconsider. Camp 2 that believe they can hear a difference and share this with others having the same findings when in this case changing a usb cable (like more solid bass, mid, air, relaxed whatever). They say in their turn.. How can it be that when changing a usb cable we as a group do hear exactly the same changes and how can it be that those changes are mostly identical to what the brand says the cable does. Are all of us stupid or easy to be manipulated people? In this case we tested audioquest. This is enough for camp 2 to claim that it does make a difference. The camp that i belong to. Again thats why we will always have camp 1 and 2. As a sys admin i believe to be a more rational person than the average man. But still... Camp 1 would now say... Again this itsnt a real claim so please consider posting this kind of replies elsewhere as this is a rational place. Camp 2 would response and say: for us it is enough proof. And so we spent more money on buying what others might say is plecebo stuff and will be fully happy doing so.. Have a good day as I now will continu claiming and solving cases in the rational world of IT, thank god (lol).


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## castleofargh

we're pretty comfy with electricity by now, and the behavior of a passive component such as a cable is really not on the list of mankind's unsolved scientific mysteries. of course different cables can have different electrical properties, and of course said properties when pushed too far in a given direction will have consequences on the complete electrical circuit that may in turn change the output signal. it was never a matter of can a cable change the sound, but when can a cable change the sound? and are those circumstances normal circumstances? and will it be audible?

all I can say is that USB cables have specs, those specs are defined for the standard with small tolerances to make manufacturing reasonable. so we can either have a USB cable to spec which will of course never be much different from another USB cable to spec and the discussion can end there. 
or we can have fully out of spec USB cables and then whatever happens is a mystery because we're outside the USB standard and we shouldn't.
the rest is about the user's environment, a small cabin lost in a valley might not require the shielding and grounding precautions of a device standing between high voltage cables and cellphone relays. again we need to estimate what we consider normal. and the last unknown of course are the devices plugged on each side of the cable. even if a vast majority of USB devices use the same chipset, different DACs are still different DACs with different designs and specs. the cable that allegedly makes the soundstage better for one system, is absolutely not ensured to do the same on different gears. I've said that before, but we're dealing with electrical circuits, not with Lego. 

as for practical experience and logic:
some will find a turd DAC so unstable and poorly protected that any change results in a different sound. and they will be very happy to come and say they have proof that USB cables change sound audibly. 
some will buy all the crazy audiophile special cables with cryogenic treatment and virgin tears for shield, and again when they end up with one so out of spec that it really impacts the signal, but not enough to create errors breaking the connection, they will come convinced they have proved the audible impact of USB cables. 
and then you have people like myself who would conclude from an audible difference between cables that at least one of the 2 cables was bad. so I would try to measure what I can and get rid of the lemon. but I wouldn't come on the forum telling everybody how they should buy some fancy and expensive USB cable. 

same experiences, different ways to jump to conclusion ^_^.

in the end those who really care should consider that for a cable the best you can do is have it be to the proper specs for the dedicated use, and have it short. the rest IMO will only matter under specific circumstances and we shouldn't generalize over specific circumstances. 
 we don't want special cables, we want very standard cables because the gears we use were designed to be plugged into very standard cables with very standard electrical specs. that is the usual and general state of things IMO.


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## gregorio

Glenn Adema said:


> Are all of us stupid or easy to be manipulated people?



The answer to that question is "yes"! Now that's not as insulting an answer as it may appear because we are ALL to an extent "easy to be manipulated people", if we weren't then we couldn't appreciate music in the first place! I disagree with many of your assertions, there is proof that we can perceive differences where there are none, there is proof that if you remove the perception biases then that "group [who] do hear exactly the same changes" no longer hear those changes. 



Glenn Adema said:


> Then we want to share our finding as we think it makes our lives better and for some reason we care about others.



And that's the problem! If you (plural) really did care about others, then you wouldn't advise them that there is definitely an audible improvement. If you (again plural) really did care about others then wouldn't you make some effort to ensure the advice you're providing is accurate, especially as audiophile cables are not an insignificant cost? Namely: That some people have perception biases which lead to a perceived improvement but those perception biases are subject to change, while others don't have those perception biases and do not perceive a difference in the first place. 

G


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## castleofargh

I was looking for that quote from Feynman:
*“Science is what we have learned about how to keep from fooling ourselves.”*
to make sure I was quoting right, but in the process found that one which is not bad either, from The pleasure of finding things out: 
*"The first principle is that you must not fool yourself, and you are the easiest person to fool."*

I agree wholeheartedly and always think I'm not being skeptical enough, despite having the will to be. then again I'm also not young and rich despite a very high motivation, so maybe will alone isn't always enough ^_^.


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## bigshot (Jan 9, 2018)

I think it's interesting when people make impassioned speeches in defense of placebo effect. Because they haven't made the effort to understand how sound works, they don't understand it. And because they don't understand it, the figure it can't be understood. Then they build up a complicated barrier of feelings and emotions to protect their precious ignorance from being questioned. Whenever someone politely offers a clue, they look on them like they're a meanie sticking a pin in a child's balloon.

I think society is becoming more and more solipsist/autistic. Everyone is inside their own head and can't interpret the input coming from outside. Everyone seems to be clutching their ignorance to their chest like a teddy bear, refusing to let go. Even if they know that they're wrong! It's interesting that this shift has happened in my lifetime. When I was a kid, it was "build a better mousetrap" and "do your homework" and "pull yourself up by your bootstraps". Now it's "safe spaces" and "trigger warnings" and "it's MY opinion". I can't wait to see what comes next. I have a feeling that a lot of this is going to collapse under its own weight and something new will replace it.



castleofargh said:


> I was looking for that quote from Feynman:
> *“Science is what we have learned about how to keep from fooling ourselves.”*
> to make sure I was quoting right, but in the process found that one which is not bad either, from The pleasure of finding things out:
> *"The first principle is that you must not fool yourself, and you are the easiest person to fool."*



Great quotes! I've always liked Mark Twain's comment, "It's better to keep your mouth shut and be thought a fool than to open it and remove all doubt."


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## amirm

Glenn Adema said:


> Camp 2 that believe they can hear a difference and share this with others having the same findings when in this case changing a usb cable (like more solid bass, mid, air, relaxed whatever).


The second part of this is not true unfortunately.  Indeed I find this the most illogical thing about audio subjectivism.  That no two subjective reviews of the same cable, gear, etc. agree with each.  And that is putting aside terms used which have no specific meaning (PRAT, micro-detail, harmonically rich, etc.).

Worse yet, two people will have violently opposing views of the same device.  One will say it has thin bass, and the other, best bass they have heard.

This happens at shows when everyone is listening to the same system and together!  



Glenn Adema said:


> Camp 1 that cannot hear any difference nor find good solid tests that might get them to reconsider.


Again, the first part of this is not true.  I can get anyone to hear differences that are not there physically.  Myself included!  Just play the same digital file a few times in a row and focus on detail, air around instruments, etc.  I guarantee you that you and everyone else will hear differences in every round even though nothing is changed!

Our hearing is very fluid in that our brain chooses what to capture from moment to moment.  The sound waves entering our ears is but one factor that is used in what we "hear."  When we test a new cable, we pay attention to figure out fidelity differences.  That very motivation all of a sudden causes us to hear detail we did not hear before (but were always there).  This happens to just about everyone.  You have to try hard, very hard to ignore this.  So I don't buy it when objectivists say they don't hear these differences.  They do.

I remember the first time I tried Foobar2000 player some years back.  I was under the mistaken assumption that by default it used exclusive access to the audio driver and hence was not subject to Windows audio stack resampling/dither.  I immediately heard better fidelity, better air, etc. when compared to Windows Media Player.  The I research and found out that it was using the same audio stack.  The difference I "heard" vanished right then and there!

The difference between the two groups is that the camp 1 is aware of our mind generating false conclusions and hence, don't put weight behind unlikely differences reported subjectively.  

Of course the keyword here is "unlikely."  Many online characters ruin audio objectivity by using poor knowledge of audio science to declare any and all things impossible or unlikely.  This by itself is anti-science and guilty of crimes nearly as bad as subjectivity.  When you see them constantly providing opinion but no research and references, your antenna should be up.  A wise man and top researcher in my group had a great line: "and unreasonable advocate is the worst of both worlds" as he referred to one of these people!  Nothing pushes people away from objectivity in audio than this kind of conduct.


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## Glenn Adema

This is getting interesting... Let's change camps for a while (or maybe longer ). Where should we stop? I bought a system about 15 years ago (all new), spend about 8k for it and was quite happy with it. Later on I bought a decent DAC (about 5 years old now), somewhat more expensive cables (AQ Coffee series, and some scientific unproven audio grade power cables (lol)), a normal PC with fidelizer pro and jplay using USB 3 for the PC output with 2 jitterbugs connected (each on 1 bus). The amplifier is Denon avc-sr1 (around 4k) with amphion creon speakers for the 2.0 part (at that time I paid around 3k for them as a set).  I have always been happy with it and it sounds better then most of the systems i have heard (again fully unproven I know) but sometimes it can be a little bit harsh for me (although using fidelizer reduces this a lot). Something about fidelizer: Fidelizer has a good theory why it does what is does on its site but there is no actual proof other then the 2000 positive paying and non paying users and their reviews.  Let's just say that the software piece works for me. Saved some money and I am currently thinking of purchasing a new system. Reviewing these posts and reactions some of you are really plugged in on a science level regarding audio rather then on a what we think is right level (even as a group ALL thinking the same) because we feel so (which was what I did, as a newby on this site). I respect that. For everything I claim there is a reason why I claim it but then again to be honest a reason why that claim is nonsense is also and maybe even more easy to find (thanks for the awareness). Most people are again and again saying what is jibberish on a scientific level but lets turn it around in a positive way and learn from one another. What would be a good buy for lets say 5k (no more money available as I am a father now (lol)). On a scientific proven level, what should we buy to get the most out of it? Where are we now (2018), what has been proven and is therefore worth some money (instead of paying for nonsense). Don't care about specific brands or models but also don't care if you do. I am very curious where we stand in this point of time. Don't care about what most people say, care about what head-fi serious members (particularly the people that replied to me before) might say on this matter. And thus hope to hear from one of you soon! First asking this as a reply so the subscribers will be reached and later on I will create a new thread for this...   (ps I am sorry if my english isn't perfect as its not my native language).


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## bigshot (Jan 11, 2018)

I've never found much correlation between price and quality, except perhaps with transducers- but there are ways of doing them on the cheap that work too.

It is VERY easy to find transparent sources for cheap. Just about any $100 blu-ray player will play CDs as well as an audiophile player. An iPod or Mac Mini will sound as good too. Amps are pretty easy as well. I have a midrange Yamaha AV receiver in my system and it sounds great and is a Swiss army knife of features. I'd suggest putting most of your budget into good speakers. Look for speakers that are capable of producing a full range of frequencies fairly loud. Don't worry so much about perfectly balanced response. The second you put it in your room, that'll change anyway. I can offer suggestions of speakers I like, but I only know the brands I have used. I'm sure there are lots of great speakers out there.

The key to a good sounding speaker system is optimizing the room and equalization. If you don't have the experience to do that yourself, just hire a geek squad kind of guy who does home theater installation and have him set it up and tweak it for you. It really isn't rocket science though. You could probably figure it out yourself with a little googling.

One other suggestion... The biggest improvement in sound that you can make is multichannel. A halfway decent 5.1 system trounces the most high end 2 channel system. Naturally, the speakers will cost more because there are more of them, and its more complicated to EQ and balance. But if you pick up an inexpensive AVR, you can add channels as you go. Start with 2.0 then add a center for 3.0. Then a sub for 3.1. Then save up and get rears for 5.1. Even stereo recordings sound better on a multichannel system with the proper DSP.

Building a system is a process of optimizing and compromising. It isn't something you just go out and buy. You have to think about it and work it a bit if you want something really good. That takes applied science, priorities and horse sense. Money can't buy you that.


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## castleofargh

I can't help for that, I'm just a poor guy thinking "cheap" long before I think "fidelity". I also never got to test seriously(as in properly with actual controls) really expensive or "special" gears. at best I've been invited to some places or heard something in a showroom(worst listening conditions ever?). I'm just not your guy for that. 
but I can at least synthesize my approach of fidelity: weak link!

 my room is too small and asymmetrical, my speakers are cheap, even with measurements and fat curtains there is only so much I can do. my desk is a fabulous resonator ...  so in comparison, I fail to find anything usually impacting the sound below -80dB to need tinkering.
at my current level I care about noises I clearly perceive, and then mainly about frequency response. when those 2 are subjectively fine for me and there is no massive issue(clipping, laggs, ...), I usually enjoying myself and feel I can stop there. that's really my zone. if I had some crazy good speakers in a great room with all the acoustic and DSP correction going great, then maybe I would get concerned by more frivolous aspects of my playback chain. simply because when the big issues are gone, the smaller issues become the big issues ^_^.  but even then, cables would come last and USB cable probably lastererer. I expect it to have the lowest objective impact out of all my gears under typical conditions.
so I'm moving the goalposts, I admit that much. I don't think in term of "can it do something?", because almost anything can have some sort of measurable impact somewhere. instead I check fidelity along the playback chain and give attention to what will tend to have a high magnitude impact.


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## bigshot

Castleofargh has a good point. It's hard to offer suggestions without knowing about your listening room and how you plan to listen. Does your room serve multiple purposes? What size and shape is it? Do you have flexibility in room layout or are you stuck with what the wife allows? Those sorts of questions probably have more impact on sound quality than how much money you have to spend.


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## gregorio

Glenn Adema said:


> On a scientific proven level, what should we buy to get the most out of it?



As others have said, it depends on your circumstances but we can make some generalisations, although some of them are more along the lines of where not to spend your money. For example, digital audio is pretty much a done deal. We can get perfect digital audio out of very cheap devices these day, perfect beyond the capabilities of the human ear. So DACs, USB cables/purifiers and source equipment is not where you want to be spending your money, probably 5% of your 5k budget is plenty, unless you need additional functionality (like a network server or something). Amps too are basically a done deal, just get the right power/load (again depending on functionality, like surround sound for example). Cables, power or audio, again, done deal. The obvious place to target most of your money is the transducers, speakers and/or HPs, this can and will make a significant difference, although don't assume that higher price = better fidelity, very expensive is often no better and sometimes worse than moderately expensive. And with speakers, there's a big bang for the buck with acoustic treatment and some of the digital room correction stuff. If it were me, speakers, treatment and room correction is where the vast proportion (probably 85-90%) of my budget would go.

G


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## amirm

Glenn Adema said:


> What would be a good buy for lets say 5k (no more money available as I am a father now (lol)). On a scientific proven level, what should we buy to get the most out of it?


Starting with scientifically proven speakers, you need to purchase the brands/models that are designed that way.  I know of only one brand where controlled listening tests backed by millions of dollars of published peer-reviewed research: Harman.  That is the parent company and specific brand is Revel and some of their JBL line (e.g. M2 and 3867).  No other company designs products from ground up that way.  No Revel speaker for example is allowed to be released regardless of technical merit until it beats its competition in double blind tests.  

Fortunately they have excellent products from bookshelf on up to full tower.  See the Performa 3 for example: http://revelspeakers.com/revel-performa3.html.  Since speakers don't obsolete hardly at all, I would put at least half of your budget there.

Next you need a way to deal with your room.  Revel/Harman speakers are designed to have similar off-axis response to on-axis.  This means the sound you get above a few hundred hertz, is almost independent of the room you put them in.

Below a few hundred hertz, the room dominates the sound you hear, not the speaker.  Since we put some 25% emphasis on bass when it comes to fidelity, it is essential to optimize that.  No system regardless of price has proper bass without this.  Again, the room is controlling this, not the speaker, not the amp, not the DAC, not the cable, etc.  And it is very simple physics of sound waves combining.

Free options for above include measuring your room (see my tutorial here: https://audiosciencereview.com/foru...om-measurement-tutorial-for-dummies-part-1.4/) and then optimizing your seating positiona and speakers.  But that still leaves bass issues even in best circumstances.  You need electronic correction for best results ("Room EQ").  I plan to write a tutorial on doing this manually but there are automated systems out there.  If you are using a PC as a source, Dirac Live is a turnkey solution but pricey (about $1000 from what I recall).  That is what I use on my 2-channel system.

Speaking of source, I trust you have already gotten on the bandwagon of streaming music from a computer/NAS/server.  All of this fidelity talk is nonsense if convenience is not there.  Get Tidal subscription while you are at it and enjoy more music than you can for hundred lifetimes for the price one CD a month!  I use Roon software plus Tidal and Dirac and life is great.  

For amplifier, get something with lots of power.  If there is anything that can make amps sound different is when they run out of power.  Class-D amps have gotten good bringing the price of such a solution way down.  If you can though, make sure to seek out reviews as Class-D amps interact with the load/speaker, resulting in potentially colored sound (in high frequencies).

For DACs, the Topping D30 remains my favorite at just $129 shipped in US: https://audiosciencereview.com/forum/index.php?threads/topping-d30-dac-measurement-and-review.2016/

These are all decisions and tips that can be heavily defended with audio science/engineering.


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## bigshot

Or you can just call the Geek Squad and they'll set you all up!


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## dzasta

still going strong I see...

the gift that keeps on giving!


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## Glmoneydawg

dzasta said:


> still going strong I see...
> 
> the gift that keeps on giving!


Yep...not sure why this is still going....sounds like 1/2 the posters have it all figured out....should be offline listenng to they're scientifically perfect systems


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## Strangelove424

Glmoneydawg said:


> Yep...not sure why this is still going....sounds like 1/2 the posters have it all figured out....should be offline listenng to they're scientifically perfect systems



There is no perfection in science and science makes no attempt to achieve it. Perfection, or atleast the pursuit of perfection in audio, is the just about most unscientific thing a person could do.


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## Glmoneydawg

Strangelove424 said:


> There is no perfection in science and science makes no attempt to achieve it. Perfection, or atleast the pursuit of perfection in audio, is the just about most unscientific thing a person could do.


Yep...art not science


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## Strangelove424

Glmoneydawg said:


> Yep...art not science



USB cables are definitely a science. But science is not about perfection, and nobody whose scientific believes in unicorns or perfection, which both exist in a fantasy land.

See my sig for further explanation.


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## Glmoneydawg

Strangelove424 said:


> USB cables are definitely a science. But science is not about perfection, and nobody whose scientific believes in unicorns or perfection, which both exist in a fantasy land.
> 
> See my sig for further explanation.


There will always be things we haven't figured out how to measure....yet


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## bigshot

I wish there was a way to measure the thing that causes audiophiles to spend a great deal of money on things for which there is no reason to believe that they will improve sound quality in any way shape or form.


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## Strangelove424

Glmoneydawg said:


> There will always be things we haven't figured out how to measure....yet



That's another great example of the nirvana fallacy I linked in my sig. "There is phenomenon science cannot measure, therefore scientific measurements are imperfect and can't be trusted."


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## castleofargh

Glmoneydawg said:


> There will always be things we haven't figured out how to measure....yet


let's be serious for a sec. a song, be it while recording or while hearing it is at a given position, is nothing more that a value of air pressure going up or down over time. finding out if such a simple function is being modified significantly or not by an external factor like a component in a playback chain is absolutely trivial to check. same for the electrical signal going out of the DAC, which is this time a voltage value going up or down over time. still as simple as it gets. what made up complexity could come to make this complicated and mysterious?
checking how much a signal was changed after switching a cable is the most basic kind of measurement one can do. what we may not always know is why a change occurs, or how to influence that change. but observing and quantifying that change is a walk in the part. it's not like we're trying to explain gravity or some deep psychological stuff. 
 at the end of the day, the output signal changes or it doesn't. if it does, what matters from an objective point of view is the magnitude of that change relatively to the signal itself. 
as for our subjective ability to notice a difference in sound, well the only proper way to test that is some kind of A/B blind test to verify if the variation is noticeable or not by the subject. anything else might interfere with a proper comparison of the 2 sounds, or add variables which aren't related to sound at all(placebo, price tag, look...). the consistent refusal from the audiophile community to test things properly and subsequent myth and anecdotes don't demonstrate mystery and things yet to learn how to measure properly. they only demonstrates malpractice, ignorance, and laziness. 


now in a more general view of the world, it is indeed fair to say that there are plenty of things we have yet to learn how to measure and define. we most likely only know a tiny bit of what is the real world. but in this instance, we're discussing playback audio. the very system exists based on recording and playing back some amplitude over time. all audio formats and media so far were made based on that principle. we do not try to record more than that, and given all the means to record, modify, store, and play back a sound, it would be quite the luck to have some unknown variable that's significant for music, to somehow manage to come along for the ride each and every time.
we might also need to have some receptor in our body for that variable that we don't know about(somehow it's the less fishy aspect of that made up hypothesis). and then some guy goes to make a USB cable that will impact that variable significantly for customers, despite how the guy doesn't know the variable to exits, how to perceive or quantify it, or how to affect it voluntarily. 
 call me narrow minded, but I'll stick to the idea of air pressure moving the eardrum, even if it's quite simple and boring, at least it aligns with all of our observations so far. which is a pretty good argument to have confidence in the model.


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## gregorio

Strangelove424 said:


> USB cables are definitely a science.



I think I'm probably with Glmoneydawg on this one, particularly when it comes to audiophile USB cables, although it's close. Audiophile USB cables have relatively little to do with science but plenty to do with visual appearance, price point and various other marketing factors such as advertising, pseudo-science, etc. But as marketing itself is part science and a large part art, then I somewhat agree that it's mainly an art.



Glmoneydawg said:


> There will always be things we haven't figured out how to measure....yet



Agreed! While science has clearly demonstrated that appearance, price and marketing in general can significantly affect our perception of what we're hearing, it hasn't figured out how to measure that effect .... yet.

G


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## Glmoneydawg (Feb 6, 2018)

gregorio said:


> I think I'm probably with Glmoneydawg on this one, particularly when it comes to audiophile USB cables, although it's close. Audiophile USB cables have relatively little to do with science but plenty to do with visual appearance, price point and various other marketing factors such as advertising, pseudo-science, etc. But as marketing itself is part science and a large part art, then I somewhat agree that it's mainly an art.
> 
> 
> 
> ...





gregorio said:


> I think I'm probably with Glmoneydawg on this one, particularly when it comes to audiophile USB cables, although it's close. Audiophile USB cables have relatively little to do with science but plenty to do with visual appearance, price point and various other marketing factors such as advertising, pseudo-science, etc. But as marketing itself is part science and a large part art, then I somewhat agree that it's mainly an art.
> 
> 
> 
> ...


my comment was directed at sound science in general....i dont even have a usb cable in my system


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## gregorio

Glmoneydawg said:


> my comment was directed at sound science in general....i dont even have a usb cable in my system



Again, I broadly agree. There are many "audiophile" tweaks and bits of kit besides USB cables and in all cases sound science cannot measure the amount of bias/affect on perception which is caused by gullibility/susceptibility to the marketing of those tweaks. All sound science can do is use a method of testing which allows us to more accurately perceive what we're hearing by eliminating those marketing induced biases.

G


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## Strangelove424

gregorio said:


> I think I'm probably with Glmoneydawg on this one, particularly when it comes to audiophile USB cables, although it's close. Audiophile USB cables have relatively little to do with science but plenty to do with visual appearance, price point and various other marketing factors such as advertising, pseudo-science, etc. But as marketing itself is part science and a large part art, then I somewhat agree that it's mainly an art.



Making a well-shielded USB compliant cable comes down to good standards, maths, and sciences. Cable design, texture, shininess, and all the attributes of marketing I would agree are artistic. That's not to denigrate the artistic value, I remember former sound science regular Steve Eddy readily admitted to his cables having no sound advantage, being works of craftsmanship only, and I admit they were pretty. So in that regard, yes, there's an art to the visuals and marketing (as I am readily willing to admit there is 'an art' to almost anything, making these distinctions somewhat moot) though I'm not entirely sure Glmoneydawg was meaning it in precisely this way.


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## gregorio

Strangelove424 said:


> [1] Making a well-shielded USB compliant cable comes down to good standards, maths, and sciences.
> [2] So in that regard, yes, there's an art to the visuals and marketing (as I am readily willing to admit there is 'an art' to almost anything, making these distinctions somewhat moot) though I'm not entirely sure Glmoneydawg was meaning it in precisely this way.



1. Yep, I'm not saying there's no science involved. Although there are examples of audiophile USB cables which are not actually USB compliant, DAC designs which are not compliant with the basic tenets of Sampling theory and USB DACs which appear to have difficulty handling what is transmitted by USB. Indicating that a bit more science would have been wise!

2. I'm not sure that's exactly what he meant either. 

G


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## Dipper

I hear a difference. The micro usb cable that came with fiio q1 is bad. I'm using the micro usb cable that came with a ps4 controller. It is longer with a heavier weight. The sound difference is big. Music is not muffled, soundstage more defined. Piano notes don't linger or clump up. Faster decay.


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## chef8489

Dipper said:


> I hear a difference. The micro usb cable that came with fiio q1 is bad. I'm using the micro usb cable that came with a ps4 controller. It is longer with a heavier weight. The sound difference is big. Music is not muffled, soundstage more defined. Piano notes don't linger or clump up. Faster decay.


Right. So a usb cable from a controller magically made sound change even tough there is no sound going through the cable then the cable that came with the Fiio device.


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## colonelkernel8

Dipper said:


> I hear a difference. The micro usb cable that came with fiio q1 is bad. I'm using the micro usb cable that came with a ps4 controller. It is longer with a heavier weight. The sound difference is big. Music is not muffled, soundstage more defined. Piano notes don't linger or clump up. Faster decay.



I've read this whole thread (shocking I know) and I'm going to say this from a position of authority as an engineer:

A USB cable cannot, cannot, cannot, influence the sound in an audible way short of actual, real problems in the cable, or poor USB PHY implementation on the source or the target (in which case any USB cable will not solve the problem). This is simply the truth. You may believe you hear differences; I can assure you they are not there. All of the evidence and testing in the world will prove this to be the case and indeed has proven this to be the case, which is why devices like this exist: http://teledynelecroy.com/options/productseries.aspx?mseries=482&groupid=140. We could compare the differential eye diagram on an oscilloscope using either the worlds most expensive USB audiophile cable or a standard, Belkin $20 cable of the same length and I promise you there would be no difference with regards to the data sent and how the receiving PHY would interpret it.

Head-Fiers need to stop preaching this irrational, almost religious obsession with how things unrelated to the actual performance of the cable (weight, price, appearance, materials) affect the sound. This same notion can be applied to a lot of other products too...


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## Clive101

colonelkernel8 said:


> I've read this whole thread (shocking I know) and I'm going to say this from a position of authority as an engineer:
> 
> A USB cable cannot, cannot, cannot, influence the sound in an audible way short of actual, real problems in the cable, or poor USB PHY implementation on the source or the target (in which case any USB cable will not solve the problem). This is simply the truth. You may believe you hear differences; I can assure you they are not there. All of the evidence and testing in the world will prove this to be the case and indeed has proven this to be the case, which is why devices like this exist: http://teledynelecroy.com/options/productseries.aspx?mseries=482&groupid=140. We could compare the differential eye diagram on an oscilloscope using either the worlds most expensive USB audiophile cable or a standard, Belkin $20 cable of the same length and I promise you there would be no difference with regards to the data sent and how the receiving PHY would interpret it.
> 
> Head-Fiers need to stop preaching this irrational, almost religious obsession with how things unrelated to the actual performance of the cable (weight, price, appearance, materials) affect the sound. This same notion can be applied to a lot of other products too...



Thank you for your post and your view.

Coming from a simple non technical background I agree that the data is not being changed ( lets assume the USB cables just work and the data is not changed ).

I have not posted over the past months as this forum is all about proving a theory with test results, alas I am unable to do this.

I have a idea / theory that others may wish to reflect on, a laptop and a HiFI server send data to a DAC both sound different ( well to me they do ) assuming the data is the same why do they sound different..? Noise or other rubbish being passed through the digital stage and onto the analogue stage and somehow making the music sound different. Remember the data does not change.

Can it be that different USB cables pass on this interference (noise) in varying degrees, while the digital data stays intact the SQ changes depending on USB cable's interaction on noise?


----------



## colonelkernel8 (Mar 12, 2018)

Clive101 said:


> Thank you for your post and your view.
> 
> Coming from a simple non technical background I agree that the data is not being changed ( lets assume the USB cables just work and the data is not changed ).
> 
> ...



The cable can't introduce noise (USB cables are shielded and the differential twisted pair carrying the signal is remarkably good at rejecting noise, 50dB to 70dB per *pinnahertz*). That noise would have to be introduced on the USB power line by the transmitting device (e.g. a poorly designed USB PHY). This would then need to be compounded a USB PHY design on the receiving device not be able to reject noise on the power line and also using the USB power line to power the device with little or no filtering (insanely bad design). The result then would be switching noise or buzzing and a raised noise floor. The *USB cable would be incapable of removing that noise* unless it had an active filtering circuit on the power line, which I haven't seen before, but I've seen some devices like the iFi iUSB3.0 actually regenerate a new low-noise 5V voltage and pass the signal on through with that new 5V line. But that device is almost completely useless unless there is a shockingly incompetent power supply design on a USB-powered DAC. I would hope that the kind of DAC you'd connect a several hundred (or even several thousand) dollar USB cable to would A) Not be USB powered and B) if it is USB powered have a competent power supply design.


----------



## dzasta

Clive101 said:


> Coming from a simple non technical background I agree that the data is not being changed ( lets assume the USB cables just work and the data is not changed ).
> 
> Can it be that different USB cables pass on this interference (noise) in varying degrees, while the digital data stays intact the SQ changes depending on USB cable's interaction on noise?



In its simplest form, data (in digital form) will either get to its destination or it won't. Meaning, digital data traveling from the HIFI server to the DAC through the USB cable will either get there in its original form or not. Transmission of data through a USB cable cannot, will not alter the digital data in any way, shape or form. It's a "1" or a "0". "Yes" or a "no".

Interference in the form of ground noise that may be present on the USB shielding or USB GND lines is filtered out at the DAC and in most cases should never make it to your ears at all (assuming the DAC is functioning properly).

This next part seems to be where most people get their panties in a bunch. The difference you hear is all in your head. There is no actual difference between difference USB cables. Period. We have proven this over 46 unfortunate pages of this thread using commonsense, logic, and most importantly, science, from countless qualified sources. Your mind is a powerful thing and nobody likes to hear that what they are clearly hearing with their own ears is indeed their brain playing a trick on them. Placebo is real.


----------



## amirm

colonelkernel8 said:


> The cable can't introduce noise (USB cables are shielded and the differential twisted pair carrying the signal is remarkably good at rejecting noise, 50dB to 70dB per *pinnahertz*). That noise would have to be introduced on the USB power line by the transmitting device (e.g. a poorly designed USB PHY). This would then need to be compounded a USB PHY design on the receiving device not be able to reject noise on the power line and also using the USB power line to power the device with little or no filtering (insanely bad design).


Well, insanely bad design from a super popular brands unfortunately exist.  See my measurements of a few USB cables and impact on actual output of a DAC:







Now this doesn't mean an audiophile cable is better (see my tests).  It is just that this is not a matter of impossibility.  There is a USB bus whaling inside the DAC and must be isolated very well from the rest of DAC.


----------



## bigshot

dzasta said:


> This next part seems to be where most people get their panties in a bunch. The difference you hear is all in your head. There is no actual difference between difference USB cables. Period.



Inaudible is inaudible. A USB cable is a USB cable. Either it works for the purpose, or it's broken.


----------



## colonelkernel8

amirm said:


> Well, insanely bad design from a super popular brands unfortunately exist.  See my measurements of a few USB cables and impact on actual output of a DAC:
> 
> <image redacted for brevity>
> 
> Now this doesn't mean an audiophile cable is better (see my tests).  It is just that this is not a matter of impossibility.  There is a USB bus whaling inside the DAC and must be isolated very well from the rest of DAC.



Methinks there is something else going on here. I would need to see the schematic of the USB input of the Modi 2 since the results were not replicable across different DACs. To be quite frank I wouldn't be surprised to see a somewhat poor design in the Modi 2...this is a $100 "audiophile" DAC. They are going to shave part costs in some areas so they can afford an absolutely insanely over-specced DAC chip that has specs they can market.


----------



## bigshot

colonelkernel8 said:


> Methinks there is something else going on here.



Look at the key on the side... The noise is all below -125dB.


----------



## colonelkernel8

bigshot said:


> Look at the key on the side... The noise is all below -125dB.



Missed that. Good grief, a bat couldn't hear that. That's below the THD+N of Audio Precision's highest end analyzer.


----------



## Glmoneydawg

bigshot said:


> Look at the key on the side... The noise is all below -125dB.


100% true....but the graph kinda flies in the face of "they're all the same"....audible?maybe to a bat....still obviously different though.


----------



## Glmoneydawg

colonelkernel8 said:


> Missed that. Good grief, a bat couldn't hear that. That's below the THD+N of Audio Precision's highest end analyzer.


Lol...we both have high regard for bats as audiophiles


----------



## colonelkernel8 (Mar 12, 2018)

Glmoneydawg said:


> 100% true....but the graph kinda flies in the face of "they're all the same"....audible?maybe to a bat....still obviously different though.



"Obviously different"? Not so fast. These measurements are below the usable range of the AP analyzer amirm is using...by a lot. The first useful level at this bandwidth (at best, assuming amirm is using the APx555, a $28,000 piece of kit) is the TOP of the chart he's provided here.

Just to be clear: -125 dbV is a signal that is 5e-7 Vrms. Assuming this is 1.5 Vrms (the output of the Modi 2) signal he's performing the FFT on, well, the signal is 2.5 MILLION times larger than the noise.


----------



## Glmoneydawg

colonelkernel8 said:


> "Obviously different"? Not so fast. These measurements are below the usable range of the AP analyzer amirm is using...by a lot.


Even if it  its inaccurate you would think they would still be very similar right?Just asking. ..suspect you may know better.


----------



## colonelkernel8 (Mar 12, 2018)

Glmoneydawg said:


> Even if it  its inaccurate you would think they would still be very similar right?Just asking. ..suspect you may know better.



At these levels, it could be anything affecting the test platform. Really. These are microvolts. You'd need a spectrum analyzer to accurately measure this.


----------



## Glmoneydawg

colonelkernel8 said:


> "Obviously different"? Not so fast. These measurements are below the usable range of the AP analyzer amirm is using...by a lot. The first useful level at this bandwidth (at best, assuming amirm is using the APx555, a $28,000 piece of kit) is the TOP of the chart he's provided here.
> 
> Just to be clear: -125 dbV is a signal that is 5e-7 Vrms. Assuming this is 1.5 Vrms (the output of the Modi 2) signal he's performing the FFT on, well, the signal is 2.5 MILLION times larger than the noise.





colonelkernel8 said:


> At these levels, it could be anything affecting the test platform. Really. These are microvolts.


So we are well below the threshold of audible sound....but they are still different my friend.


----------



## colonelkernel8

Glmoneydawg said:


> So we are well below the threshold of audible sound....but they are still different my friend.



Sure. But only if you're using a Modi 2 and a long USB cable.


----------



## Glmoneydawg

colonelkernel8 said:


> At these levels, it could be anything affecting the test platform. Really. These are microvolts. You'd need a spectrum analyzer to accurately measure this.


Just to be clear as long as cable is able to carry voltage/amps/load(no brainer here) it should be pretty much perfect...this has to be in non-digital electronics?


----------



## Glmoneydawg

colonelkernel8 said:


> Sure. But only if you're using a Modi 2 and a long USB cable.


Lol...we are getting to the same place.


----------



## Glmoneydawg

amirm said:


> Well, insanely bad design from a super popular brands unfortunately exist.  See my measurements of a few USB cables and impact on actual output of a DAC:
> 
> 
> 
> ...


Troublemaker.


----------



## colonelkernel8

Glmoneydawg said:


> Lol...we are getting to the same place.



I can promise that the results would have been the same with a an "audiophile" USB cable of the same length. My guess is the shielding acting as an antenna, and the Modi not being designed to deal with that. But this is outside my expertise at this point.


----------



## bigshot (Mar 12, 2018)

Glmoneydawg said:


> 100% true....but the graph kinda flies in the face of "they're all the same"....audible?maybe to a bat....still obviously different though.



For the purposes of connecting home audio components they are identical.

This is the sort of thing that confuses people. Folks stumble into sound science and they see a cable thread like this. They look at a chart without understanding the context of it and assume that there's a difference. They go out and spend too much on a cable that makes absolutely no difference whatsoever.

It's more useful to just say what colonelkernal said up front. There is no difference between USB cables. For the purposes we are all using them for, that is an accurate statement. Wasting time discussing differences more than 120dB down, is absurd.


----------



## Glmoneydawg

colonelkernel8 said:


> At these levels, it could be anything affecting the test platform. Really. These are microvolts. You'd need a spectrum analyzer to accurately measure this.





colonelkernel8 said:


> I can promise that the results would have been the same with a an "audiophile" USB cable of the same length. My guess is the shielding acting as an antenna, and the Modi not being designed to deal with that. But this is outside my expertise at this point.


Outside mine too bud....i'm here for a cheap education on digital...have always thought there where differences....but i suspected the differences where in the pre-output electonics not the digital.


----------



## Glmoneydawg

bigshot said:


> For the purposes of connecting home audio components they are identical.


No argument there...but they are different...amirim has made a real schitzz storm here


----------



## bigshot

Do you know what -120dB means? That is way beneath the noise floor of CDs.  It's in a different universe than music. There is no difference between USB cables. If they aren't broken, they are all the same.


----------



## Glmoneydawg

bigshot said:


> Do you know what -120dB means? That is way beneath the noise floor of CDs.  It's in a different universe than music. There is no difference between USB cables. If they aren't broken, they are all the same.


Totally understand the db/audible thing....but apparently the no difference thing doesn't fly...outside of audibility of course...check out the graph with the ziggy lines i hate so much.


----------



## colonelkernel8 (Mar 12, 2018)

Glmoneydawg said:


> Totally understand the db/audible thing....but apparently the no difference thing doesn't fly...outside of audibility of course...check out the graph with the ziggy lines i hate so much.


Ok, you can stop trolling now. All that test did is effectively show the effect of different lengths of USB cable on the Modi DAC. Without testing an "audiophile" cable of the same length, it's a moot point.


----------



## Glmoneydawg

bigshot said:


> Do you know what -120dB means? That is way beneath the noise floor of CDs.  It's in a different universe than music. There is no difference between USB cables. If they aren't broken, they are all the same.


Also feel like your issue is with Amirm....he posted the evidence


----------



## Glmoneydawg (Mar 12, 2018)

colonelkernel8 said:


> Ok, you can stop trolling now.


Ok....sorry...just trying to get Bigshot goin(sorry bud)


----------



## Glmoneydawg

colonelkernel8 said:


> Ok, you can stop trolling now. All that test did is effectively show the effect of different lengths of USB cable on the Modi DAC. Without testing an "audiophile" cable of the same length, it's a moot point.


Are you suggesting an "audiophile "cable would fair differently?sorry you walked in to that one.


----------



## colonelkernel8

Glmoneydawg said:


> Are you suggesting an "audiophile "cable would fair differently?sorry you walked in to that one.



I'd bet every penny I own you'd see the same "noise" with an "audiophile" USB cable equal in length to the "cheap USB" cable referenced in the study.


----------



## Glmoneydawg

colonelkernel8 said:


> I'd bet every penny I own you'd see the same "noise" with an "audiophile" USB cable equal in length to the "cheap USB" cable referenced in the study.


100%agree with you.....but i think there are things we haven't figured out how to measure yet...its what keeps me going in this hobby bud.....don't Wreck-It for me lol.


----------



## amirm

colonelkernel8 said:


> Methinks there is something else going on here. I would need to see the schematic of the USB input of the Modi 2 since the results were not replicable across different DACs. To be quite frank I wouldn't be surprised to see a somewhat poor design in the Modi 2...this is a $100 "audiophile" DAC. They are going to shave part costs in some areas so they can afford an absolutely insanely over-specced DAC chip that has specs they can market.


It is not a matter of parts or this specific dac.  It is a demonstration that there are measurable differences due to USB cables so it is best not to assume it is impossible.


----------



## colonelkernel8

amirm said:


> It is not a matter of parts or this specific dac.  It is a demonstration that there are measurable differences due to USB cables so it is best not to assume it is impossible.



Don't your results show that this didn't happen with the Behringer?


----------



## amirm

Glmoneydawg said:


> 100% true....but the graph kinda flies in the face of "they're all the same"....audible?maybe to a bat....still obviously different though.


That's it.  If we say that is impossible then we don't know enough about the design of the products in question.  

Even on audibility for all the talking we do we don't bother to measure.  We just assume.  As objectivists we need to back what we say with data.


----------



## amirm

colonelkernel8 said:


> Don't your results show that this didn't happen with the Behringer?


Sure.  But of the thousands of DACs, I have tested a tiny fraction.

I am not making a case for audibility of USB cables mind you.  I just like to see us not use assumptions but confirmation of the same using data.


----------



## amirm

bigshot said:


> It's more useful to just say what colonelkernal said up front. There is no difference between USB cables. For the purposes we are all using them for, that is an accurate statement. Wasting time discussing differences more than 120dB down, is absurd.


You say there is no difference and then go and admit there can be "120 db down?"  Can't have it both ways.


----------



## colonelkernel8

amirm said:


> You say there is no difference and then go and admit there can be "120 db down?"  Can't have it both ways.



*sigh*.

Show me the test with an equivalent length of "audiophile" cable or use a shorter length of the cheap USB cable. Otherwise you're comparing apples and oranges.


----------



## chef8489

How many times were each cable tested? How many different cables were tested? What was the setup for testing and measuring means?


----------



## bigshot

amirm said:


> You say there is no difference and then go and admit there can be "120 db down?"  Can't have it both ways.



A cable has a purpose. Either it succeeds in accomplishing that purpose, or it doesn't. The fact that you are incapable of understanding that says a lot about the value of your comments. You're looking at the motes in eyes. Your comments have no purpose. Goodnight, Gracie.


----------



## bigshot (Mar 13, 2018)

Glmoneydawg said:


> Ok....sorry...just trying to get Bigshot goin(sorry bud)



There's enough stupidity without trying to make me go to the same place! I don't go there. My eyes are on the prize. That's why I make people so irritated.



Glmoneydawg said:


> i think there are things we haven't figured out how to measure yet.



Define that and you'll be the God of this forum. Until then, we'll depend on what we already know.

RABBIT HOLE, AHOY!


----------



## Clive101 (Mar 13, 2018)

dzasta said:


> This next part seems to be where most people get their panties in a bunch. The difference you hear is all in your head. There is no actual difference between difference USB cables. Period. We have proven this over 46 unfortunate pages of this thread using commonsense, logic, and most importantly, science, from countless qualified sources. Your mind is a powerful thing and nobody likes to hear that what they are clearly hearing with their own ears is indeed their brain playing a trick on them. Placebo is real.



Ah yes the Placebo effect.
It works both ways.
Perhaps there is a difference in SQ and some cannot hear it..? The Placebo working in mysterious ways..?
Perhaps the brain is more sensitive than can be measured by a machine..?


----------



## bigshot (Mar 13, 2018)

Clive101 said:


> Perhaps the brain is more sensitive than can be measured by a machine..?



When it comes to audibility of noise in an audio signal, what evidence do you have to believe that? The thresholds of perception are pretty well researched and documented. If you click on the link in my sig, you'll find evidence that the most annoying kind of noise possible becomes inaudible after about -45dB.

Convincing yourself that you can hear things you really can't is normal placebo. Convincing yourself that you don't hear things that are clearly audible is a lot more difficult.


----------



## Clive101 (Mar 13, 2018)

bigshot said:


> When it comes to audibility of noise in an audio signal, what evidence do you have to believe that?



Nice question but was a "perhaps" in my post. Who knows what we are able to measure in the future..?  So I offer no evidence.

Anyone got one of these 28 k machines in the UK with a decent Hifi I will bring some USB cables, DAC, music server etc  over and hopefully we can get some sort of test..? Driving distance from London please.


----------



## Glmoneydawg

bigshot said:


> There's enough stupidity without trying to make me go to the same place! I don't go there. My eyes are on the prize. That's why I make people so irritated.
> 
> 
> 
> ...


fair enough.


----------



## colonelkernel8

bigshot said:


> There's enough stupidity without trying to make me go to the same place! I don't go there. My eyes are on the prize. That's why I make people so irritated.
> 
> 
> 
> ...



Disagree. People always want some little room for the "unknown" (i.e. god in other philosophical arguments) so they can continue justifying their biases. It's the very notion of "god of the gaps" in practice.


----------



## amirm

chef8489 said:


> How many times were each cable tested? How many different cables were tested? What was the setup for testing and measuring means?


It is all in the article I referenced.  Half a dozen or so "cables" were tested including an audiophile one.  The measuring means is an Audio Precision analyzer which I use for all of my reviews and measurements.  The analysis is the output of the DAC which is the only thing that matters (not the USB signal).  In other words, I am measuring how the waveforms change.

I also tested another audiophile USB cable here.  

And what do you mean how many times?  You expect the data to change in each insertion?


----------



## amirm

colonelkernel8 said:


> *sigh*.
> 
> Show me the test with an equivalent length of "audiophile" cable or use a shorter length of the cheap USB cable. Otherwise you're comparing apples and oranges.


Why?  I thought you were saying USB cables can't make a difference? 

That aside, did you not read the article?  That is exactly the conclusion I stated in there: that shorter cables do better.


----------



## amirm

bigshot said:


> A cable has a purpose. Either it succeeds in accomplishing that purpose, or it doesn't.


I am measuring the analog output of a DAC in those tests.  So there is noting binary there.  Audio DACs are mixed-domain devices -- part analog, part digital.  In such systems the digital side can impact the analog performance.  And that impact is shown in my actual measurements.



> The fact that you are incapable of understanding that says a lot about the value of your comments. You're looking at the motes in eyes. Your comments have no purpose. Goodnight, Gracie.


Well, why don't you reflect on your own commentary.  I am showing hard, concrete evidence that *changing USB cables and nothing else, makes the analog output of a DAC change.*  You go around promoting myths that this can't happen.  It of course does and there is real engineering explanation why that is the case.

You are not a designer and go by lay intuition and stuff you read online from folks just like you.  In a science forum, you need to expect to get corrected when you misstate how the real world works especially when that correction is accompanied by real data.  Just because you wear the hat of audio objectivism, doesn't mean you know how things work.


----------



## colonelkernel8

amirm said:


> I am measuring the analog output of a DAC in those tests.  So there is noting binary there.  Audio DACs are mixed-domain devices -- part analog, part digital.  In such systems the digital side can impact the analog performance.  And that impact is shown in my actual measurements.
> 
> 
> Well, why don't you reflect on your own commentary.  I am showing hard, concrete evidence that *changing USB cables and nothing else, makes the analog output of a DAC change.*  You go around promoting myths that this can't happen.  It of course does and there is real engineering explanation why that is the case.
> ...



Your silly rhetorical games essentially forfeit any authority you may claim to have. You claim some empirical result, don’t perform an apples to apples comparison, and don’t attempt to offer any explanation as to why the spurious results were only measured in one configuration, all while using a device with a THD+N ABOVE the noise you’re supposedly measuring. Bye.


----------



## bigshot

amirm said:


> I am showing hard, concrete evidence that *changing USB cables and nothing else, makes the analog output of a DAC change*



Inaudibly


----------



## amirm

colonelkernel8 said:


> Your silly rhetorical games essentially forfeit any authority you may claim to have. You claim some empirical result, don’t perform an apples to apples comparison, and don’t attempt to offer any explanation as to why the spurious results were only measured in one configuration, all while using a device with a THD+N ABOVE the noise you’re supposedly measuring. Bye.


I am happy to explain.  That explanation is also in my article on understanding audio measurements.  

Making sure everyone is able to follow us, colonelkernel is saying that my measurements are below the level of THD+N of the Audio Precision analyzer.  And hence must represent an impossibility.  The confusion is understandable but does not hold water.

As I explain in my article, we are able to use the power of signal processing to hugely lower the noise floor of our measurements.  The THD+N meter is a dedicated circuit inside the Audio Precision.  I do not use that for these measurements.  Instead, the digitized output of the DAC is directly converted to frequency domain using FFT.  By using a large FFT (32K in my case), we substantially reduce the measured noise floor of the system.  Roughly speaking, we gain a whopping 32 dB or so of noise advantage here versus performing time domain analysis using THD+N meter and such! 

This is why you routinely see measurement floors that are down to -140 dB or even lower not only in what I show but in what stereophile and other reviewers show.  Using this technique we can dig really deep to find very small differences that otherwise would be impossible.   Here is an example from JA in stereophile using a similar AP analyzer to mine: https://www.stereophile.com/content...preamplifier-headphone-amplifier-measurements







Notice the Y axis goes down to a whopping -150 dB!  That is 0.0000032% in THD percentage!  No audio equipment at room temp can remotely do this let alone the combination ADC in the analyzer and DAC.  We are talking greater noise floor of 25 bits!  We will be lucky if we can get 20 dB out of real devices.

The reason we can do this again is because this measurement includes signal processing in software that allows us to sharply reduce the measurement noise (by spreading its bandwidth over many FFT bins).

So no, the limitation of THD+N meter in AP has no bearing whatsoever in my or JA's measurements above because we are not using it.  

And my results are *absolutely apples to apples.*  I keep the DAC and analyzer the same and only change the USB cable.  That one change causes the measured output to vary.

Now if you are saying that is not the case since USB cables are not the same length then you need to completely re-write your original post and say that mere length change can impact the analog output of the DAC.  And in doing so, lose the complete war of USB cable's can't possibly make changes in our audio gear.  You can't have it both ways.

And to be clear I am not at all advocating people buy fancy USB cables.  If you worry at all, use a shorter one.  I just like us to accurately explain how the technology works rather than using assumptions as facts.


----------



## colonelkernel8 (Mar 13, 2018)

amirm said:


> I am happy to explain.  That explanation is also in my article on understanding audio measurements.
> 
> Making sure everyone is able to follow us, colonelkernel is saying that my measurements are below the level of THD+N of the Audio Precision analyzer.  And hence must represent an impossibility.  The confusion is understandable but does not hold water.
> 
> ...


*
Because this is getting obnoxious and petty to the extreme:*

Sure, USB cables can make a difference to the analog output. Now, despite your supposed "objective" intent, you're now officially holding water for snake oil salesman and hucksters, who will invariably link to your research without context to fleece customers whose audiophile OCD would lead them to believe that any drop in noise, even in the range of -125 dBV to -130 dBV on a $100 DAC with an improper USB interface design, is worth spending big money on cables for. Congrats dude.


----------



## bigshot

I just added a handy clarification to make your chart more understandable to people.


----------



## amirm

colonelkernel8 said:


> Sure, USB cables can make a difference to the analog output. Now, despite your supposed "objective" intent, you're now officially holding water for snake oil salesman and hucksters, who will invariably link to your research without context to fleece customers whose audiophile OCD would lead them to believe that any drop in noise, even in the range of -125 dBV to -130 dBV on a $100 DAC with an improper USB interface design, is worth spending big money on cables for. Congrats dude.


Nope.  Here is the conclusion section of my article:





And I said this for the review of TotalDAC USB cable:





So my recommendations are very clear against spending money on such cables.  

What you want is a world where we spread misinformation based on incorrect lay understanding about how audio devices work and not investigate anything.  Problem is that one day someone who knows better will nail you to the wall with explanation of the architecture and measurements and then, you lose credibility in everything else you say.  And with it, you damage the very good cause of audio objectivity for the rest of us.

I get why we do it.  If we say something is impossible, then we don't face the challenge of audibility.  It is a powerful debating technique.  It is just that it is not a good argument in some cases and this is one of them.


----------



## amirm

BTW, there is a powerful message here.  That unlike what many subjectivists say, we can measure differences between USB cables.  And that there is nothing wrong with our tools in that manner.  Once we have that data we use psychoacoustics to show audibility or lack thereof.  No longer can they say that they hear something we can't measure.  We absolutely can.  Our instrumentation due to power of signal processing is exceptionally sensitive and is able to tease out such differences.


----------



## chef8489

amirm said:


> It is all in the article I referenced.  Half a dozen or so "cables" were tested including an audiophile one.  The measuring means is an Audio Precision analyzer which I use for all of my reviews and measurements.  The analysis is the output of the DAC which is the only thing that matters (not the USB signal).  In other words, I am measuring how the waveforms change.
> 
> I also tested another audiophile USB cable here.
> 
> And what do you mean how many times?  You expect the data to change in each insertion?


Yes you test multiple times and you also test with different sources. You really dont understand how to do scientific tests. You can not do a true test on a cable and only test it once with just one source or one dac.


----------



## colonelkernel8 (Mar 13, 2018)

amirm said:


> BTW, there is a powerful message here.  That unlike what many subjectivists say, we can measure differences between USB cables.  And that there is nothing wrong with our tools in that manner.  Once we have that data we use psychoacoustics to show audibility or lack thereof.  No longer can they say that they hear something we can't measure.  We absolutely can.  Our instrumentation due to power of signal processing is exceptionally sensitive and is able to tease out such differences.



Not seeing how noise at -125 dB could in any way contribute to "psychoacoustics"...

Stop lying about what your data shows. If an $80 USB powered desktop recording ADC/DAC reduces the (tiny, almost immeasurable) noise of your cheapo long run of USB to the same level as the short run of audiophile cable, then it's obviously a (nearly immeasurably small) problem with the USB design in the Modi DAC. Not some magical property of the cable we now need to address. Why are you rejecting this obvious conclusion?

My bet is that the Modi USB ground is left floating relative to the power ground coming from Modi's PSU, and we're getting some RF noise from the USB shielding material over that longer run of cable (which is effectively an antenna). But you don't want to address design reasons why this happens with the Modi DAC, you just want to keep basking in whatever silly conclusions you want to believe in. *Well, you HAVE NOT sufficiently proven that the USB cable makes ANY difference without comparing identical run lengths of the "audiophile" cable and the standard USB cable.* You've only proven that the Modi DAC doesn't isolate its USB input from the output as well as the Behringer, but none of your tested situations cause anything that comes close to being audible, or even "psychoacoustically" audible...whatever that means.


----------



## chef8489 (Mar 13, 2018)

colonelkernel8 said:


> Not seeing how noise at -125 dB could in any way contribute to "psychoacoustics"...
> 
> Stop lying about what your data shows. If an $80 USB powered desktop recording ADC/DAC reduces the (tiny, almost immeasurable) noise of your cheapo long run of USB to the same level as the short run of audiophile cable, then it's obviously a (nearly immeasurably small) problem with the USB design in the Modi DAC. Not some magical property of the cable we now need to address. Why are you rejecting this obvious conclusion?
> 
> My bet is that the Modi USB ground is left floating relative to the power ground coming from Modi's PSU, and we're getting some RF noise from the USB shielding material over that longer run of cable (which is effectively an antenna). But you don't want to address design reasons why this happens with the Modi DAC, you just want to keep basking in whatever silly conclusions you want to believe in. *Well, you HAVE NOT sufficiently proven that the USB cable makes ANY difference without comparing identical run lengths of the "audiophile" cable and the standard USB cable.* You've only proven that the Modi DAC doesn't isolate its USB input from the output as well as the Behringer, but none of your tested situations cause anything that comes close to being audible, or even "psychoacoustically" audible...whatever that means.


And this is why we test multiple cables with multiple sources multiple times and log the data. It is called the scientific method of testing. You do not have sufficient data to prove anything as pointed out here.

What is funny is the three of us are agreeing about usb cables and no sound difference, just not about what is being measured or the means. The fact is that the digital audio is not changed. There can be no change between cables and no sound difference between cables or different means of digital transport through a digital cable. Ie tosling, coaxial, usb all sound the same through the same source. The headphones and dac will cause the source of the sound. Headphones primarily dac secondary. The circuitry of the amp will also play a role if solid state vs tube and what tubes will play a roll in the coloration of the sound, but the digital cable will have no effect on the sound except in extreme cases to induce interference that for some reason is not filtered out by the dac.


----------



## bigshot

Why do people spend so much money on testing equipment and time on testing, and they never bother to investigate the thresholds of perception? It seems to me that if someone is writing a review of home audio equipment, focusing on things no human being can possibly hear is a complete waste of time.


----------



## amirm

chef8489 said:


> Yes you test multiple times and you also test with different sources. You really dont understand how to do scientific tests. You can not do a true test on a cable and only test it once with just one source or one dac.


The confusion is yours I am afraid.  Nothing I wrote is about "science."  It is simple engineering measurements which neither the manufacturer, nor it seems the people scream loudly in forums perform.  Once you do, you understand that your assumptions about how audio equipment works may be wrong. Again, this is not science.  To think it is and elevate it such as a debating tactic, is just wrong.

And remember, all I have to do is one scenario where the USB cables make measurable difference.  That one instance invalidates the notion of impossibility.  Which is what started this discussion.


----------



## colonelkernel8

amirm said:


> The confusion is yours I am afraid.  Nothing I wrote is about "science."  It is simple engineering measurements which neither the manufacturer, nor it seems the people scream loudly in forums perform.  Once you do, you understand that your assumptions about how audio equipment works may be wrong. Again, this is not science.  To think it is and elevate it such as a debating tactic, is just wrong.
> 
> And remember, all I have to do is one scenario where the USB cables make measurable difference.  That one instance invalidates the notion of impossibility.  Which is what started this discussion.



You might have to form a new forum called “Sound Philosophy” if you want to get this absurdly pedantic.


----------



## chef8489 (Mar 13, 2018)

amirm said:


> The confusion is yours I am afraid.  Nothing I wrote is about "science."  It is simple engineering measurements which neither the manufacturer, nor it seems the people scream loudly in forums perform.  Once you do, you understand that your assumptions about how audio equipment works may be wrong. Again, this is not science.  To think it is and elevate it such as a debating tactic, is just wrong.
> 
> And remember, all I have to do is one scenario where the USB cables make measurable difference.  That one instance invalidates the notion of impossibility.  Which is what started this discussion.


No because equipment could be faulty or it could be a fluke measurement. Since when is Engineering not science?


----------



## amirm

chef8489 said:


> No because equipment could be faulty or it could be a fluke measurement.


Sure.  But until you can demonstrate how the fault got in there, you are just creating FUD as a debating tactic to lower the value of measurements.  I expect that from subjectivists.  Not anyone who subscribes to "science."

You should celebrate objective data not work as hard as you can to say audio measurements can be wrong.


----------



## amirm

colonelkernel8 said:


> You might have to form a new forum called “Sound Philosophy” if you want to get this absurdly pedantic.


This one is already philosophical seeing how much angst you all are showing about hard, concrete measurement data on the very topic we are discussing.  So much fear is created that we are lending a hand to the other camp that we rather paper over that and shoot the messenger  than admit the fact that our lay intuition of audio equipment is not how USB DACs work.

Let me ask you this.  Earlier you said this:


colonelkernel8 said:


> All of the evidence and testing in the world will prove this to be the case and indeed has proven this to be the case, which is why devices like this exist: http://teledynelecroy.com/options/productseries.aspx?mseries=482&groupid=140.



Do you understand how that piece of test equipment has no value whatsoever in this context?


----------



## chef8489

You can not have objective data with just one measurement from one source. You have no way to say if it is the cables, the dac, or the source. You have not measured the same cables with another source and the same dac or the same cables with same source and another dac. You have not measured the same cables multiple times to see if you got the same measurements each time to see if there is fluctuation wit the same source and dac. For all you know it could be the dac causing problems with current and noise, could be the source transmitting electrical noise across the cables, could be a noisy environment and the cables picking up like an antenna, or hey it could by some chance be a difference in the usb cable. But you will never know as you have not tested.


----------



## colonelkernel8

amirm said:


> Sure.  But until you can demonstrate how the fault got in there, you are just creating FUD as a debating tactic to lower the value of measurements.  I expect that from subjectivists.  Not anyone who subscribes to "science."
> 
> You should celebrate objective data not work as hard as you can to say audio measurements can be wrong.



I’m fully willing to admit an objective difference in the signals...if you’re willing to admit they are objectively inaudible and your experiment using what was likely an out of spec USB transceiver in the Modi was objectively flawed in that it didn’t report the same inaudible noise across both devices using the same cable and your absurdly low bar threshold of evidence of “USB cables can create a different output” was also objectively flawed.


----------



## amirm

chef8489 said:


> You can not have objective data with just one measurement from one source. You have no way to say if it is the cables, the dac, or the source. You have not measured the same cables with another source and the same dac or the same cables with same source and another dac.


Do you guys don't bother reading anything presented to you?  I measured more than one DAC and source.  Here is the other source which is a Sonore MicroRendu streamer, with the same DAC:







And DAC:






Honestly, this is the problem.  You all seem more interested in shouting and complaining than spending a minute reading something and learning....


----------



## colonelkernel8 (Mar 13, 2018)

amirm said:


> This one is already philosophical seeing how much angst you all are showing about hard, concrete measurement data on the very topic we are discussing.  So much fear is created that we are lending a hand to the other camp that we rather paper over that and shoot the messenger  than admit the fact that our lay intuition of audio equipment is not how USB DACs work


 Honestly I can’t tell if you’re just trolling at this point. What a bunch of inanity.

No one is disputing the following: when using a DAC with an out of spec USB transceiver, USB cables can introduce noise.


----------



## amirm

colonelkernel8 said:


> I’m fully willing to admit an objective difference in the signals...if you’re willing to admit they are objectively inaudible and your experiment using what was likely an out of spec USB transceiver in the Modi was objectively flawed in that it didn’t report the same inaudible noise across both devices using the same cable and your absurdly low bar threshold of evidence of “USB cables can create a different output” was also objectively flawed.


No, no, not.  There is nothing "out of spec" in Modi's USB receiver.  If there were, it would drop audio samples and that creates a ton of distortion, not what you see here.  

That I have tested too by the way in the context of reviewing ISO Regen where I strung together USB extension cables until it "went out spec:"






Notice the hugely elevated noise floor with ISO regen failing to recover the data whereas the powered hub (in yellow) did.  

So no, nothing here is about data recovery which the USB spec is all about.  If data is lost you will absolutely know it.  It will glitch, pop, mute, etc.  Indeed I posted audio samples for above where the audible difference is very clear (see the thread).

What we are talking about is quality of USB power and activities of the digital USB interface inside the DAC is impacting the DAC (chip)'s reference, clock or analog outputs.  In other words, these are secondary effects and there is nothing whatsoever in USB spec that reads on it.  The spec's job is done the moment the data is captured reliably by the DAC.  It cares not whether you as a designer then let the noise bleed into the rest of your device.  That is the engineer's problem, not USB spec/standards group.


----------



## chef8489

colonelkernel8 said:


> Honestly I can’t tell if you’re just trolling at this point. What a bunch of inanity.
> 
> No one is disputing the following: when using a DAC with an out of spec USB transceiver, USB cables can introduce noise.


Yes but in this case any usb cable would induce the same noise. It is either caused by the power line on the usb cable, or other interference picked up that the dac is not filtering out correctly. You might even get noise from the circuitry on the dac itself.


----------



## colonelkernel8

chef8489 said:


> Yes but in this case any usb cable would induce the same noise. It is either caused by the power line on the usb cable, or other interference picked up that the dac is not filtering out correctly. You might even get noise from the circuitry on the dac itself.



I know.


----------



## colonelkernel8

amirm said:


> No, no, not.  There is nothing "out of spec" in Modi's USB receiver.  If there were, it would drop audio samples and that creates a ton of distortion, not what you see here.
> 
> That I have tested too by the way in the context of reviewing ISO Regen where I strung together USB extension cables until it "went out spec:"
> 
> ...



Agreed. My poor choice of words. I did mean poorly engineered.


----------



## castleofargh

some might have noticed that headfi isn't exactly the researcher's den. the title of this section sure is wishful, but it's not a statement of content. 

about the debate of those last pages, I honestly don't know what the problem is. I'm like the next guy, I love a good _auto da fe_, but I must have missed something amirm wrote. so far it seems to me like he wished to show that in some cases, switching a cable could have measurable impact. did he claim anything more? 
I have measurable differences on my old Odac with different cables. they're at the limit of what I can measure with my cheap gears and at the limit of what my amp can output with fidelity anyway, but there is a consistency in the changes, suggesting they're probably there. I was never able to notice an audible change nor do the figures suggest I would, on that all the participants right now seem to agree. but if the standing position is that a USB cables can't influence the signal coming out of DACs, then his or my experience oppose the idea. 

I'd also like to point out that in the end USB isn't one unique protocol or even one unique cable standard. since the first USB cables, specs have changed. some DAC are usb powered, so that's some potential extra fun, even more so when some audiophile cables might be totally out of spec and even more than just a cable. so I'm all for letting the door open for possible changes. if only because it's hard to test all configurations. now if someone takes that opportunity to come in making empty claims about the better soundstage of cable XXXX, I'll provide half the wood to burn him alive. 
equal opportunity for the witch and the inquisitor. ^_^


----------



## bigshot (Mar 13, 2018)

As I always say... Show me something with audible levels of noise or distortion. Otherwise, I'm going to assume it doesn't matter and wait for proof that it does. I really don't have much interest in theoretical sound. I am more concerned with problems that need addressing.


----------



## chef8489

castleofargh said:


> some might have noticed that headfi isn't exactly the researcher's den. the title of this section sure is wishful, but it's not a statement of content.
> 
> about the debate of those last pages, I honestly don't know what the problem is. I'm like the next guy, I love a good _auto da fe_, but I must have missed something amirm wrote. so far it seems to me like he wished to show that in some cases, switching a cable could have measurable impact. did he claim anything more?
> I have measurable differences on my old Odac with different cables. they're at the limit of what I can measure with my cheap gears and at the limit of what my amp can output with fidelity anyway, but there is a consistency in the changes, suggesting they're probably there. I was never able to notice an audible change nor do the figures suggest I would, on that all the participants right now seem to agree. but if the standing position is that a USB cables can't influence the signal coming out of DACs, then his or my experience oppose the idea.
> ...


My issue is just that his tests are incomplete and inconclusive with how he presented it as there just is not enough data to prove it is the cables and not something else in the chain. I do give props for even testing and measuring. That is far more than many of these I hear a difference people( amirm is not one of these) do,


----------



## chef8489

bigshot said:


> As I always say... Show me something with audible levels of noise or distortion. Otherwise, I'm going to assume it doesn't matter and wait for proof that it does. I really don't have much interest in theoretical sound. I am more concerned with problems that need addressing.


Thing is we would agree that you will not get it and dont waste your money on cables. A in spec cheap cable will sound just the same as a in spec expensive cable on proper in spec equipment.


----------



## zeroselect




----------



## donunus

I don't know if this is the thread to post this in but I have a question about USB DAC connections/contacts. My Geek Out 1000 intermittently sounds softer and louder when I rock the dac up and down. It also goes out of phase sometimes just like how an analog jack would behave. How is this possible if the analog information hasn't even been converted from digital yet? Does digital audio numbers say louder and softer when it has better or worse connection contact quality? It seems absurd to me lol. It also seems that if something like this happens, the more I would believe usb cable quality matters because of this even being a direct connection behaving like an analog cable. I did hear differences between USB cables before but didn't think much of it since they weren't huge differences and I just thought that maybe it could have just been due to one having beads and one with no RF beads. hmm


----------



## colonelkernel8

donunus said:


> I don't know if this is the thread to post this in but I have a question about USB DAC connections/contacts. My Geek Out 1000 intermittently sounds softer and louder when I rock the dac up and down. It also goes out of phase sometimes just like how an analog jack would behave. How is this possible if the analog information hasn't even been converted from digital yet? Does digital audio numbers say louder and softer when it has better or worse connection contact quality? It seems absurd to me lol. It also seems that if something like this happens, the more I would believe usb cable quality matters because of this even being a direct connection behaving like an analog cable. I did hear differences between USB cables before but didn't think much of it since they weren't huge differences and I just thought that maybe it could have just been due to one having beads and one with no RF beads. hmm



I promise the RF "beads" changed nothing. They've been chucking abrasive media for sand blasting into cables for a while now. Total silliness.

What sounds like might have been happening is the power contacts were not making good...contact, increasing the resistance and lowering the voltage across the amplifier portion of the Geek Out. That's my guess.


----------



## chef8489 (Mar 23, 2018)

donunus said:


> I don't know if this is the thread to post this in but I have a question about USB DAC connections/contacts. My Geek Out 1000 intermittently sounds softer and louder when I rock the dac up and down. It also goes out of phase sometimes just like how an analog jack would behave. How is this possible if the analog information hasn't even been converted from digital yet? Does digital audio numbers say louder and softer when it has better or worse connection contact quality? It seems absurd to me lol. It also seems that if something like this happens, the more I would believe usb cable quality matters because of this even being a direct connection behaving like an analog cable. I did hear differences between USB cables before but didn't think much of it since they weren't huge differences and I just thought that maybe it could have just been due to one having beads and one with no RF beads. hmm


No. You would have to alter the actual data. The only thing that would affect it is if the pins were loosing contact and you were loosing data, but this would not become softer unless it is written in the software of the dac to do so when loss of data. Usually when loss of data you hear skips, pops and cracks.

"What sounds like might have been happening is the power contacts were not making good...contact, increasing the resistance and lowering the voltage across the amplifier portion of the Geek Out. That's my guess."
This is most likely what is happening. Has nothing to do with the dac but the amp section.


----------



## amirm

I don't know about out of phase but some DACs have muting circuits that get activated when the input connection gets lost.  And some then ramp up when that connection is active again.  So that may be what you are hearing.

I have a loaned LH Labs DAC for review.  I will check to see if it does this.


----------



## skwoodwiva

artpiggo said:


> I don't know what I have been heard is wrong or not. please correct me if I misunderstand the concept.
> 
> I have been explained that when data transfer, it comes in form of electricity (voltage,current) inside the cable. (It is not exactly 010101 inside cable but it represents in electricity form)
> 
> ...


dieletric  absorption 101... 
Causes smearing  in analog or digital signals.
Teflon is the answer.
More here , first hit on google
http://www.gracedesign.com/about/design.html


----------



## bigshot

Bad source of information there.


----------



## chef8489

bigshot said:


> Bad source of information there.


I agree completly.


----------



## skwoodwiva (Mar 24, 2018)

bigshot said:


> Bad source of information there.


My comments on DA or the link?
Surly not DA, it is real along with other cable physics.
The link seemed on point but it was a quick grab off google...
Oooo I see it is not about low level cable, but caps- OK.
Look up Jon Risch at audio asylum...
https://www.audioasylum.com/messages/tweaks/1582/the-audio-cable-faq


----------



## chef8489

skwoodwiva said:


> My comments on DA or the link?
> Surly not DA, it is real along with other cable physics.
> The link seemed on point but it was a quick grab off google...
> Oooo I see it is not about low level cable, but caps- OK.
> ...


I dont think you understand how digital audio works and the difference between a digital and analogue signal.


----------



## skwoodwiva

chef8489 said:


> I dont think you understand how digital audio works and the difference between a digital and analogue signal.


So please tell why ALL the best digital cables are FPE and the very best TFE
Thanks Sir for the education. I am serious & polite...


----------



## colonelkernel8

skwoodwiva said:


> So please tell why ALL the best digital cables are FPE and the very best TFE
> Thanks Sir for the education. I am serious & polite...


How are you defining “best”? Most expensive? The correlation there in audiophile world is probably negative price to performance in terms of digital cable.


----------



## colonelkernel8 (Mar 24, 2018)

colonelkernel8 said:


> How are you defining “best”? Most expensive? The correlation there in audiophile world is probably negative price to performance in terms of digital cable.



Furthermore, the “shark fin” effect from dielectric capacitance wouldn’t affect the integrity of the signal, merely shift the “rising” and “falling” edges of the square wave by like...picoseconds. But it would be UNIFORM. So the signal would be 100% fine. None of this can affect the “sound” the cable carries. Period. Look at an “eye” chart of a differential signal. The “shark fin” effect is there and it’s expected. But that’s the whole point of differential signaling.


----------



## castleofargh

well under some conditions, with some weirdo cables linked to weirdo stuff, just moving the cable around did have some real big effects. perhaps that's what @skwoodwiva was thinking of as the initial question was involving movements. but I have to admit the significant stuff I've observed were all with analog signal. I don't know how much of that could impact a USB cable. 
personally if I had to bet I would certainly bet on the plug having changes in the quality of the contacts when moved around, and being a USB powered device gives even more incentive to suspect that as the cause for changes in sound.  but that's still just a guess.


----------



## skwoodwiva

colonelkernel8 said:


> How are you defining “best”? Most expensive? The correlation there in audiophile world is probably negative price to performance in terms of digital cable.


Coaxial digital, the best are always foamed TFE, come on man...


----------



## skwoodwiva

Get a Belden catalog , G wizz...


----------



## chef8489

skwoodwiva said:


> Get a Belden catalog , G wizz...


Again i do not think you understand digital. As long as the digital signal gets there it does not matter if the cable is $1.00 or $1,000.00.  an amazon basics digital cable is just as good and will sound identical to any other digital cable. That was the whole reason for digital audio. As long as the data gets there it will sound the same.


----------



## skwoodwiva

chef8489 said:


> Again i do not think you understand digital. As long as the digital signal gets there it does not matter if the cable is $1.00 or $1,000.00.  an amazon basics digital cable is just as good and will sound identical to any other digital cable. That was the whole reason for digital audio. As long as the data gets there it will sound the same.


You using mind over you ears, man that is the modern problem...


----------



## chef8489

skwoodwiva said:


> You using mind over you ears, man that is the modern problem...


No you are under placebo. That is the problem. You not understanding the difference in analouge and digital and falling for marketing. The industry relies on your brain and ears to lie to you. That is how they make the money.


----------



## skwoodwiva

chef8489 said:


> No you are under placebo. That is the problem. You not understanding the difference in analouge and digital and falling for marketing. The industry relies on your brain and ears to lie to you. That is how they make the money.


I agree to disagree with you time will tell....


----------



## Glmoneydawg (Mar 24, 2018)

skwoodwiva said:


> I agree to disagree with you time will tell....


Your problem here is that this is the sound science area....if you say something you may have to back it up with proof of some sort...graphs,test ,articles ect...having said that,a mother bat can locate her baby in a colony of a million bats using sound....and we cant explain it....so dont take offence if you get challenged for evidence bud.If you want to learn about digital audio,this is the place to be though...some clever people in here.


----------



## chef8489

skwoodwiva said:


> I agree to disagree with you time will tell....


Time will tell. I have been working with digital audio for over 20 years. I have used cheap and expensive analogue and digital cables. They have been tested over the years by many profesionals and many profesionals have explained it here that are not trying to sell overpriced cables. There is a huge difference in digital and analogue audio signal and how they work.


----------



## Glmoneydawg

chef8489 said:


> Time will tell. I have been working with digital audio for over 20 years. I have used cheap and expensive analogue and digital cables. They have been tested over the years by many profesionals and many profesionals have explained it here that are not trying to sell overpriced cables. There is a huge difference in digital and analogue audio signal and how they work.


I have to agree here...differences are usually in the the analogue pre out electonics of digital  gear.


----------



## chef8489

Glmoneydawg said:


> I have to agree here...differences are usually in the the analogue pre out electonics of digital  gear.


Differences are how the audio signal is transfered from source. One us analogue and sound can be affected by the cable makeup, the other is digital where as long as the 1 and 0 get there the make up of the cable does not matter and does not affect the sound. As we are talking cables.


----------



## Glmoneydawg

chef8489 said:


> Differences are how the audio signal is transfered from source. One us analogue and sound can be affected by the cable makeup, the other is digital where as long as the 1 and 0 get there the make up of the cable does not matter and does not affect the sound. As we are talking cables.


Agreed.....digital signal isn't affected the way analog is.


----------



## skwoodwiva

Cartma said:


> As with everything, you start out as a skeptic and with an open mind you are able to stumble across pieces of equipment that you can't believe you went with-out.
> After trying a few USB cables I came across the Nordost Blue Heaven USB. This was the first USB cable that actually made an improvement in my system instead of just sounding slightly different. I then decided to go all out and get the next step up.. the Nordost Heimdall 2 USB. This thing made as much, if not more of an improvement then a power cable or interconnect. But the question is WHY?


The op asked, why
You all say it doesn't matter so
Why does Belden & others make a dam- expensive digital foamed Teflon coax cable?


----------



## chef8489 (Mar 24, 2018)

skwoodwiva said:


> The op asked, why
> You all say it doesn't matter so
> Why does Belden & others make a dam- expensive digital foamed Teflon coax cable?


Because they can make money on it plain and simple. It is easy to convince people they need expensive cables. Much easier to convince them they do then show them they dont.


----------



## colonelkernel8 (Mar 25, 2018)

skwoodwiva said:


> The op asked, why
> You all say it doesn't matter so
> Why does Belden & others make a dam- expensive digital foamed Teflon coax cable?



For longer runs of cable possibly. But this doesn’t make it “better” in some way for shorter runs.

Anyway, this thread is regarding USB, not coax. Coax isn’t differential like USB is, which is why parasitic capacitance in the insulation may (at frequencies much higher than SPDIF) have an effect on the receiver being able to lock to the signal. Not a problem with differential signaling.


----------



## colonelkernel8

skwoodwiva said:


> I agree to disagree with you time will tell....



Time has told.


----------



## colonelkernel8

chef8489 said:


> Because they can make money on it plain and simple. It is easy to convince people they need expensive cables. Much easier to convince them they do then show them they dont.


It’s more likely they sell Teflon insulated cable for its heat resistant properties more than literally anything else. This is a perfectly legitimate engineering need.


----------



## chef8489

colonelkernel8 said:


> It’s more likely they sell Teflon insulated cable for its heat resistant properties more than literally anything else. This is a perfectly legitimate engineering need.


If you are running a cable where enviroment thermal properties would affect the internal wiring maybe so, but usb cables dont get hot by themselves.


----------



## colonelkernel8

chef8489 said:


> If you are running a cable where enviroment thermal properties would affect the internal wiring maybe so, but usb cables dont get hot by themselves.


Of course. This is referring to a coax cable in the case of skwoodwiva’s post. As far as I know no one is selling Teflon insulated USB cable in bulk. Other differential signaled serial IO cable perhaps, like RS-485 being used in an industrial application.


----------



## GrussGott (Mar 25, 2018)

chef8489 said:


> Differences are how the audio signal is transfered from source. *One us analogue and sound can be affected by the cable makeup, the other is digital where as long as the 1 and 0 get there the make up of the cable does not matter and does not affect the sound. As we are talking cables.*



Yes, the USB cable is the physical layer, but don't we need to talk about both physical and software, i.e., the USB protocol, as it's the total transport system that ultimately affects audio?

Thus isn't the issue here that for, say, file transfers, the USB file transfer protocol (software/firmware) will wait until it has all of the bits, so if one is lost due to error of a crappy cable, the protocol asks for it again until all bits are received, thus for USB file transfers, software/firmware compensates for a bad cable amongst other issues.

However with the USB audio protocol (streaming) this isn't the case because with, say, a live phone call, you can't pause the call to wait for the missing bits as error correction so the stream simply continues and we all hear the missing bits on our audio streams as glitches ... similar to walking too far away from bluetooth.  That is, software doesn't compensate for missing bits.

So isn't the key to good USB audio streams, which don't pause for error correction, that you ensure you eliminate every possible cause of error including crappy cables with crappy connectors?


----------



## bigshot

GrussGott said:


> So isn't the key to good USB audio streams, which don't pause for error correction, that you ensure you eliminate every possible cause of error including crappy cables with crappy connectors?



Unless you can verify that there is an audible difference, you're assuming that there is a problem which may not even exist. The first step is to make sure there is an audible impact on the sound. Once you've done that, you can go looking for solutions.

Why waste time focusing on theoretical degradations in sound quality when you can focus that attention on real and observable ones?


----------



## GrussGott (Mar 25, 2018)

bigshot said:


> *Unless you can verify *that there is an audible difference



I ain't no expert but I would think that's easy to verify in a semi-thought experiment right now ... use bluetooth as an example.

In bluetooth, which also has a non-pausing audio stream, play a song and start walking in a straight line away from your laptop / source.  What will happen is that, at a certain point, you'll get glitching and then suddenly massive glitching.  This is because the software on headphones starts getting missing bits which it initially tries to correct for, but is quickly overwhelmed so it just dumps the stream, which is why you go quickly from light glitches to huge ones.  The distance is too far for the power of the signal, and all kinds of things are causing only a few bits to get through to the receiver, which you hear as glitches.

If you really got nerdy, you could walk back and find the first point of glitching - the point where you're just starting to hear a glitch - there should be an audible drop in music quality because the software is correcting for missed bits by looking at the one before and after and trying to fill in the gap, and it doesn't always guess right.  The point is, in a non-pausing audio stream you can and do miss bits, and you can hear it in small or big ways.

So there, now you've proven that audio streaming across a medium (air in this case) causes an audible drop in music quality which is a simple extension of how non-pausing audio streams work and the fact that any missed bits cause a drop in quality which, with enough dropped bits, results in a dropped connection.

*Now take USB *- in USB the medium of stream transmission is a physical wire.  Since you're transmitting a non-pausing audio stream just like in bluetooth, you can do the same thought experiment.  Imagine a USB wire 1 mile long ... you wouldn't be getting much or any signal your DAC could decode at that length.  Start shrinking the length of the cable ... at some point just like BT you'd get a glitchy signal.  And if you started making small length decrements you'd find a point where the USB software was correcting for the missed bits which causes a drop in quality because you're not hearing the actual bits sent (if the sent bit is different than the guessed bit - which would happen at least occasionally)

So there, now you've proven that with USB audio streaming the receiver doesn't pause the stream to request for lost bits and you can very easily cause stream interference and dropped bits which the firmware tries to correct for but will quickly get overwhelmed.  If the USB receiver is correcting for a few missed bits, it's obviously guessing, thus for certain sounds it'll be wrong thus a drop in quality.  If there are enough missed bits it'll simply pass along the gaps which you'll hear as glitches.

So if we can easily cause USB glitches with a long USB cable ... what other factors cause missed bits?  Probably a lot.

*Now, does all of that mean a 1 foot unobtanium USB cable improves sound quality over a cheapie? *likely not, but we'd have to inventory every single source of dropped bits in that system and if one of them was, say, a cheap connector or EMI from a nearby subwoofer, and the unobtanium cable had great connectors and heavy shielding, then yeah it improved the sound simply because the receiver is getting the sent bits rather than error correcting for missing ones.


----------



## amirm

GrussGott said:


> *Now take USB *- in USB the medium of stream transmission is a physical wire. Since you're transmitting a non-pausing audio stream just like in bluetooth, you can do the same thought experiment. Imagine a USB wire 1 mile long ...


Most USB DACs today use what is called "asynchronous USB" transfers.  They work just like data now.  They are fetched "faster than real-time" and output as needed by the DAC.  So they are not streaming the data.

Any lost samples will cause severe distortion in audio due to discontinuity in samples.  The type of fidelity differences people talk about cannot be explained by data loss.\

That said, it is incorrect to interpret USB's only role as "1" and "0."  Power is provided over USB for many lower cost DACs.  And the ground shared with its analog output of the DAC in many cases.  This means that it is very possible and happens frequently that noise is transmitted from the PC all the way to the audio equipment even though no 1s and 0s are lost.  There are lots of reports of people hearing the activities of their computers through their DAC, proving that such problems are real.  And the system does NOT work as people assume.


----------



## bigshot

GrussGott said:


> So there, now you've proven that audio streaming across a medium (air in this case) causes an audible drop in music quality which is a simple extension of how non-pausing audio streams work and the fact that any missed bits cause a drop in quality which, with enough dropped bits, results in a dropped connection.



I'm not an expert in this, but my impression of digital audio is that it's pretty much an all or nothing thing. You have error correction which can work to a point, but if you step over the line, it glitches big. There isn't a "twilight zone" where it fades smoothly into glitching.


----------



## skwoodwiva

bigshot said:


> I'm not an expert in this, but my impression of digital audio is that it's pretty much an all or nothing thing. You have error correction which can work to a point, but if you step over the line, it glitches big. There isn't a "twilight zone" where it fades smoothly into glitching.


Well that does not explain the Sony DVPs7000 phenomenon. As a transport it is still sought after.


----------



## bigshot

What is that phenomenon?


----------



## skwoodwiva

bigshot said:


> What is that phenomenon?


A early 90s player coax & opical out, not much as a cd or dvd stand-alone, cheap op amps.
But they hit a stunning home run as a tranport. It read the foil like none other at least for under 5K it was 600.00. It still may beat all comers


----------



## GrussGott (Mar 25, 2018)

amirm said:


> That said, it is incorrect to interpret USB's only role as "1" and "0."  Power is provided over USB for many lower cost DACs.  And the ground shared with its analog output of the DAC in many cases.  This means that it is very possible and happens frequently that noise is transmitted from the PC all the way to the audio equipment even though no 1s and 0s are lost.  There are lots of reports of people hearing the activities of their computers through their DAC, proving that such problems are real.  And the system does NOT work as people assume.



This.  The USB-cables-don't-matter people and/or the it's-all-1s-and-0s people have no idea what they're talking about.

To be fair, neither do I, but I listen to people like Benson:

_All USB Type-C (USB-C) Cables and Accessories are not created equal. Some will charge most efficiently, others might just fry your battery. Google Chromebook engineer and Caped Cable Crusader Benson Leung has been testing USB Type-C (USB-C) cables off Amazon, and it’s not just the no-brand products that have been failing. Benson’s campaign mostly consists of ordering USB Type-C (USB-C) cables off Amazon, testing them to see if they meet the minimum standards or if they’re just knock-offs, and then leaving Amazon reviews. Cables and chargers fail in all sorts of different ways, although incorrect resistors seem to be a common problem that Benson’s been finding. bensonapproved.com lists all USB Type-C (USB-C) Cables and Accessories approved by Benson. For more info follow us on Twitter @bensonapproved or contact us at bensonapproved@gmail.com_​And the bottom line is, USB cables matter FOR EVERYTHING including audio quality.

Why that is true is massively varied depending on software, firmware, hardware, and operating environment, but it's true.


----------



## chef8489 (Mar 25, 2018)

GrussGott said:


> This.  The USB-cables-don't-matter people and/or the it's-all-1s-and-0s people have no idea what they're talking about.
> 
> To be fair, neither do I, but I listen to people like Benson:
> 
> ...


Yes we do know what we are talking about. When the Dac is usb powered and designed badly where interference is heard across the line or the pc is causing noise to be transmitted that is a different issue al together. You are dealing with bad circuity and design. This is completely different to a usb cable changing how the music sounds. In a situation like this even a cheap well designed insulated cable might fix the problem, but even an expensive cable probably wont. You will have to isolate the noise the circuitry is causing.Usually a powered usb hub will fix this issue.

If it is connecting the ground of the usb to the ground of the analogue circuitry it is a really crappy design.


----------



## skwoodwiva (Mar 25, 2018)

chef8489 said:


> Yes we do know what we are talking about. When the Dac is usb powered and designed badly where interference is heard across the line or the pc is causing noise to be transmitted that is a different issue al together. You are dealing with bad circuity and design. This is completely different to a usb cable changing how the music sounds. In a situation like this even a cheap well designed insulated cable might fix the problem, but even an expensive cable probably wont. You will have to isolate the noise the circuitry is causing.Usually a powered usb hub will fix this issue.
> 
> If it is connecting the ground of the usb to the ground of the analogue circuitry it is a really crappy design.


 In my opinion you do not, Sir ,you miss what error correction catches & the result is audible...
That is why the Sony player was so good error correction never or rarely kicked in.


----------



## chef8489 (Mar 25, 2018)

skwoodwiva said:


> In my opinion you do not, Sir ,you miss what error correction catches & the result is audible...
> That is why the Sony player was so good error correction never or rarely kicked in.


I was not even talking about that. I was talking about usb powered dacs where the ground line is causing interfierence. If you are going to talk crap atleast be on the same page. He was quoting an earlier post that had nothing to do with error correction or the sony.


----------



## skwoodwiva (Mar 25, 2018)

chef8489 said:


> I was not even talking about that. I was talking about usb powered dacs where the ground line is causing interfierence. If you are going to talk crap atleast be on the same page. He was quoting an earlier post that had nothing to do with error correction or the sony.


So it is not true that error correction is inherently in all digital audio to prevent hearing damage that errante bits could cause?
Oh chip mfgs tell me it is not so....


----------



## colonelkernel8

skwoodwiva said:


> In my opinion you do not, Sir ,you miss what error correction catches & the result is audible...
> That is why the Sony player was so good error correction never or rarely kicked in.


This is not how error detection works...it doesn't matter how "good" the Sony player was. The confirmation bias is serious in this thread.


----------



## colonelkernel8 (Mar 25, 2018)

skwoodwiva said:


> So it is not true that error correction is inherently in all digital audio to prevent hearing damage that errante bits could cause?



NO. Hearing damage? What? Error correction is necessary in CD players because of scratches in the polycarbonate or other physical defects in the media. It's called Reed-Soloman error correction code. ENTIRELY different than USB transmission.

Edit: Let me further this: because of buffers and asynchronous transmission, if there is a packet error in the USB transmission, the packet is automatically resent, you will not hear this because it's not playing back the data at the exact same time it's receiving it. The packet can be corrected before it is ever converted into analog sound information.


----------



## chef8489

skwoodwiva said:


> So it is not true that error correction is inherently in all digital audio to prevent hearing damage that errante bits could cause?
> Oh chip mfgs tell me it is not so....


What are you talking about. You lost yourself with that one. You really have no clue what you are talking about.


----------



## skwoodwiva (Mar 25, 2018)

colonelkernel8 said:


> NO. Hearing damage? What? Error correction is necessary in CD players because of scratches in the polycarbonate or other physical defects in the media. It's called Reed-Soloman error correction code. ENTIRELY different than USB transmission.


Hmm well then you are sure there is no newer form of correction?
Raw bits conveying what dymamics they please? Then I learned something,
My appologies....


----------



## colonelkernel8 (Mar 25, 2018)

skwoodwiva said:


> Hmm well then you are sure there is no newer form of correction?
> Raw bits convening what dymamics they please? Then I learned something,
> My appologies....



I think you are conflating synchronous digital transmission formats like SPDIF with USB data transmission, which are two entirely different things.

Finally, NONE of this has to do with cables.


----------



## skwoodwiva

colonelkernel8 said:


> I think you are conflating synchronous digital transmission formats like SPDIF with USB data transmission, which are two entirely different things.
> 
> Finally, NONE of this has to do with cables.


So if errors occur how does the DAC or USB handle them?
Is there not something?


----------



## chef8489 (Mar 25, 2018)

skwoodwiva said:


> So if errors occur how does the DAC or USB handle them?
> Is there not something?


Most of the time when data is lost due to a bad cable you hear pops and cracks or other artifacts. In this case replace the cable with an in spec functioning cable and all should be good.

Now dont confuse this with a badly encoded mp3 or other digital file. The same file when transmitted on a functioning cable will be perfect, but malfunctioning cable there will be artifacts or loss of audio all together as the data does not arrive.


----------



## bigshot (Mar 25, 2018)

skwoodwiva said:


> A early 90s player coax & opical out, not much as a cd or dvd stand-alone, cheap op amps.
> But they hit a stunning home run as a tranport. It read the foil like none other at least for under 5K it was 600.00. It still may beat all comers



Is it better at reading scratched or scuffed discs? Or perhaps burned media? Because digital audio generally is what it is. It can't extract better sound out of a disc than any other way of reading a disc. It either reads it or it doesn't. I've never found a CD player since the 80s that isn't audibly transparent. I have a $60 Walmart cheapie CD player that I've compared to my Oppo and it sounds identical.


----------



## GrussGott (Mar 25, 2018)

There are 3 questions:
(1.) Is a usb cable capable of affecting the sound quality in any way?  Yes.  build a 1000' USB cable to find out.

(2.) Can a usb cable "roll" sound?  Maybe, depending on the source, the environment, the dac, the firmware, hardware, and the software.

(3.) Will an unobtanium USB cable always sound better than a cheapie?  Probably not, but depends on the source, the environment, the dac, the firmware, hardware, and the software.

/thread.


----------



## chef8489

GrussGott said:


> There are 3 questions:
> (1.) Is a usb cable capable of affecting the sound quality in any way?  Yes.  build a 1000' USB cable to find out.
> 
> (2.) Can a usb cable "roll" sound?  Maybe, depending on the source, the environment, the dac, the firmware, hardware, and the software.
> ...


Seeing as 1# is not in spec is automatically disquallified. You are limited to 3 meters with usb 3.0 and about 5 meter with usb 2.0 without usb repeaters or hubs. Everyone knows an out of spec or faulty cable will fail. This is a stupid example trying to argue it. No one is arguing against faulty equiptment or out of spec. 

Can a usb cable change sound when in spec. No. Only other things in the chain can do that. A usb cable can not add extensipn or soundstage, dynamics, or deeper bass that many people think they are hearing with placebo.


----------



## colonelkernel8

chef8489 said:


> Seeing as 1# is not in spec is automatically disquallified. You are limited to 3 meters with usb 3.0 and about 5 meter with usb 2.0 without usb repeaters or hubs. Everyone knows an out of spec or faulty cable will fail. This is a stupid example trying to argue it. No one is arguing against faulty equiptment or out of spec.
> 
> Can a usb cable change sound when in spec. No. Only other things in the chain can do that. A usb cable can not add extensipn or soundstage, dynamics, or deeper bass that many people think they are hearing with placebo.


/thread


----------



## castleofargh (Mar 25, 2018)

can drug XXX help me heal from disease YYY? yes.
should I take that drug without knowing what it does or even any idea if I have the disease? most likely not.

there is a fine line between prevention and poisoning ourselves. audiophiles who chain up magic boxes and allegedly special cables between the computer and the DAC without measuring the results, are IMO taking random drugs because another guy said he got better when taking those.
you want an expensive cable, get it. your default cable was crap and a new one works better, great for you. it did happen to me on rare occasions. something changes or doesn't change but you enjoy music more once you're reassured by the fancy cable. that is perfectly fine too. what really matters is that you enjoy your music.
what isn't fine is to have no proper evidence of improvement, yet trying to convince people that it's a good idea to invest in USB cables for paranoid reasons.


----------



## skwoodwiva

chef8489 said:


> Most of the time when data is lost due to a bad cable you hear pops and cracks or other artifacts. In this case replace the cable with an in spec functioning cable and all should be good.
> 
> Now dont confuse this with a badly encoded mp3 or other digital file. The same file when transmitted on a functioning cable will be perfect, but malfunctioning cable there will be artifacts or loss of audio all together as the data does not arrive.


Seems you did not answer as to whether error correction exits or not on new USB/ DACs...


----------



## skwoodwiva

bigshot said:


> Is it better at reading scratched or scuffed discs? Or perhaps burned media? Because digital audio generally is what it is. It can't extract better sound out of a disc than any other way of reading a disc. It either reads it or it doesn't. I've never found a CD player since the 80s that isn't audibly transparent. I have a $60 Walmart cheapie CD player that I've compared to my Oppo and it sounds identical.


That is my whole beef w/chef...
Error correction was in play in any CD/DVD player.
So that is why the Sony was so fab. It was nearly perfect. Anything less kicks is correction & degrades sound. You just do not hear it....


----------



## colonelkernel8

skwoodwiva said:


> Seems you did not answer as to whether error correction exits or not on new USB/ DACs...


I answered this question clearly. If there is a transmit error detected with a CRC check, the packet is resent. End of story.


----------



## colonelkernel8 (Mar 26, 2018)

skwoodwiva said:


> That is my whole beef w/chef...
> Error correction was in play in any CD/DVD player.
> So that is why the Sony was so fab. It was nearly perfect. Anything less kicks is correction & degrades sound. You just do not hear it....


I want you to be aware that whatever you thought you were hearing that was special with this Sony CD player, assuming nothing was wrong with it, didn’t exist. I just thought you should know that. Error correction doesn’t do what you believe it does. If error detection isn’t working (or the disc is really damaged for instance), you don’t get a degraded sound, you get a click, a pop, or a skip. Like when you’d tap on the top of a Discman before they had FIFO buffers (they’d advertise this as “memory” of a certain length of time) built into them.

But it seems that you don’t want to understand that. You have a belief and you will defend that belief, however irrationally, forever. You’re in the wrong forum mate.


----------



## skwoodwiva

colonelkernel8 said:


> I want you to be aware that whatever you thought you were hearing that was special with this Sony CD player, assuming nothing was wrong with it, didn’t exist. I just thought you should know that. Error correction doesn’t do what you believe it does. If error detection isn’t working (or the disc is really damaged for instance), you don’t get a degraded sound, you get a click, a pop, or a skip. Like when you’d tap on the top of a Discman before they had FIFO buffers (they’d advertise this as “memory” of a certain length of time) built into them.
> 
> But it seems that you don’t want to understand that. You have a belief and you will defend that belief, however irrationally, forever. You’re in the wrong forum mate.


So, it is your control panel, but not your forum
.
Ignore me.
I am looking for others who can hear artifacts in digital processing


----------



## colonelkernel8

skwoodwiva said:


> So, it is your control panel, but not your forum
> .
> Ignore me.
> I am looking for others who can hear artifacts in digital processing



“Digital processing”. Now you’ve brought up another, entirely different subject.


----------



## chef8489

I have explained what happens when you have loss of data. As someone else said error detection and error correction for a cd are completely two different things. YOu are trying to apply one technology that applies to reading cd's to usb data transfer and you can not do that. What artifacts are you looking for in digital processing? Are you looking for artifacts from badly encoded encoded digital media? Are you looking for artifacts from faulty usb cables? Are you looking for artifacts from faulty grounds on a pcb board because it is not isolated from the analogue signal? Are you looking for a power ground loop from the transformer? How about rf frequency from badly shielded dac or capacitor whine. All these artifacts can be heard on badly designed dacs and people thing it can be fixed with a high dollar usb cable except the bad encoding.


----------



## GrussGott (Mar 26, 2018)

chef8489 said:


> Can a usb cable change sound when in spec. No. Only other things in the chain can do that. A usb cable can not add extensipn or soundstage, dynamics, or deeper bass that many people think they are hearing with placebo.



You guys.
Cables matter.  So does tons of other stuff.
Read - and, seriously R E A D, all about it from this guy.

PART 1 - What is Digital?
PART 2 - Are Bit just Bits?
Cables, Bits, and Noise: How Cables Can Make A Sound Difference

*Just look at this guy: doesn't he look like he knows a shizload more about electronics than you?*
That's mostly because he does.







*TLDR*
_*So again the ground plane isolation and signal isolators can decrease the jitter and noise going from the USB receiver to the DAC circuits, BUT they cannot eliminate it. Some always gets through.

So why even bother with asynchronous USB? *Because it DOES help a lot. With adaptive USB the clock feeding the DAC chip comes out of the USB receiver with all the rather large amount of noise and jitter already discussed. With async the DAC chip clock does come from a local oscillator, so even though it is affected by the noise from the USB receiver through the mechanisms outlined above, it is still WAY better than what you get out of an adaptive receiver._
.......
_*The result is that DACs that deal well with all of these issues are essentially non-existent. 
*_​Complete your education with this:
There's no such thing as digital: A conversation with Charles Hansen, Gordon Rankin, and Steve Silberman


----------



## chef8489

GrussGott said:


> You guys.
> Cables matter.  So does tons of other stuff.
> Read - and, seriously R E A D, all about it from this guy.
> 
> ...


Why is it we keep going around in circles over and over and address these issues in this thread. We discussed jitter prior to this. I am done with this. People dont read or research what has already been discussed. This thread is getting pretty boring with the same crap over and over. Funny people that dont know crap dont want to listen to the other engineers on here that have explained over and over. But oh well. Like I said earlier it is easier to convince people you need high end usb cables than you dont.


----------



## bigshot (Mar 27, 2018)

chef8489 said:


> Seeing as 1# is not in spec is automatically disquallified.



That's a bingo!



skwoodwiva said:


> That is my whole beef w/chef... Error correction was in play in any CD/DVD player.



Do you have any evidence that typical levels of error in transports is audible? I have never seen anything like that... only theories that it MIGHT be audible. Let me know if you find an example of a CD player that doesn't perform to redbook spec.



GrussGott said:


> *Just look at this guy:[/SIZE] doesn't he look like he knows a shizload more about electronics than you?*



I look like that guy! Believe me!

Jitter is horse poop. Anyone who talks about jitter is talking purely in theory. Jitter as it exists in consumer audio products is an order of magnitude below the threshold of audibility. The only purpose for jitter is so one audibly transparent product can convince you to spend more instead of buying a cheaper audibly transparent product. It's marketing. Show me a product with audible levels of jitter.



chef8489 said:


> Why is it we keep going around in circles over and over and address these issues in this thread. We discussed jitter prior to this. I am done with this. People dont read or research what has already been discussed.



People come and dump on Sound Science the same way people dump on Facebook. The internet is breeding a generation of self validators.


----------



## colonelkernel8 (Mar 26, 2018)

GrussGott said:


> You guys.
> Cables matter.  So does tons of other stuff.
> Read - and, seriously R E A D, all about it from this guy.
> 
> ...



This guy is a nut. I have no doubt that ground plane equipotential is an issue in gigahertz RF circuitry or some scientific instrumentation, but it’s inane here. 0.1 volts across the ground plane? On a 3.3v digital circuit? You’ve gotta be kidding me. There isn’t a ground plane in existence that has a resistance of 0.1 ohms across its furthest stretches and yet if it did you’d need a full amp of current to create a 0.1 volt potential. The resistance of a ground plane across, say, one inch on a one inch wide board is 0.000243 ohms. The highest current usage for a TCXO I could find was 10 mA. Let’s assume some madness that the whole 10 mA of current is being switched on and off causing noise. This situation would never, ever happen in a DAC but even still that’s 0.00000243 volts or -115 dBV. Inaudible by a long shot. This is nonsense.


----------



## chef8489 (Mar 26, 2018)

bigshot said:


> That's a bingo!
> 
> 
> 
> ...


I think what it is they ignore the majority of science and data and find the very few that back up the industry that sells cables as to justify their expensive purchases.


----------



## bigshot

You're right. And Colonel is right too. That guy is a nut.


----------



## GrussGott

bigshot said:


> You're right. And Colonel is right too. That guy is a nut.



if by "nut" you mean "actually has understands why cables matter", I agree!  
(and it's not just cables, it's everything, but it's also cables)

I also posted lots of info on why that is, which I didn't think would work, and it didn't.

Anyway, you can read about Darko making fun of you guys here, in case you wanted to know what experts think versus, say, you guys.

_It usually unfolds thusly: A thread is started with a link to a deluxe cable or doohickey seeking opinions on the same. The first responder bowls in with a “that looks suss to me”-type comment. The ensuing pile-on is as ugly as it is predictable. The product is either rubbished in theory or the (perceived) absence of proof from the manufacturer pointed to as proof of its snake-oil status. “Well, this ‘ere world globe suggests the world is not flat after all…but it’s nothing more than a toy – BURN HIM!”_​


----------



## chef8489

GrussGott said:


> if by "nut" you mean "actually has understands why cables matter", I agree!
> (and it's not just cables, it's everything, but it's also cables)
> 
> I also posted lots of info on why that is, which I didn't think would work, and it didn't.
> ...


That test was rubbish and not conducted correctly. We know you are just going to a website to justify your purchases. What you dont understand is most of us are strong believers in cables. Many are engineers. Many have run tests on usb and other digital cables both double blind tests set up correctly with repeating cables in the mix. They have also taken measurements by a lot of different means. But go ahead and keep going to your avanue driven website where the owner has to justify expensive usb cables. You still have not provided any empirical data backing up that a usb cable can change the digital data as it transmits to change the sound to expand the soundstage, increase the bass, increase the highs and such.This is the only thing an audiophile cable can do that a standard in spec usb cable cant that all you guys  that believe in this magical usb cable with no science behind it.


----------



## colonelkernel8 (Mar 26, 2018)

GrussGott said:


> if by "nut" you mean "actually has understands why cables matter", I agree!
> (and it's not just cables, it's everything, but it's also cables)
> 
> I also posted lots of info on why that is, which I didn't think would work, and it didn't.
> ...



Ok, cool man. He "understands" but doesn't/can't actually show it. This is sound "science", not sound "guessing". Show me that ground plane noise causes audible changes to the source signal in a DAC. Your ability to "hear" the differences of (in-spec) USB cables is about as reliable as someone's ability to "feel" the "holy spirit" in proving either to exist, which is an apt comparison given the religious nature of audiophiles.

As for Darko making "fun" of me, I couldn't care less. He can buy his multi-thousand dollar ethernet cables and speaker cable mass dampening to feed his imagination. I'm sure it's putting some kid through school...optimally where they'll learn not to believe in fairy tales and snake oil.


----------



## bigshot

GrussGott said:


> if by "nut" you mean "actually has understands why cables matter", I agree!



No, I think he is a nut in the sense that he manufactures differences that he could never hear in a controlled listening test in a million years. Nutty audiophiles are ones that worry about theoretical sound more than actual sound.

Check out the two AES seminar videos in my sig file. I think you'd find them interesting. They come with links to the test files so you can hear for yourself. If you understand what the specs and numbers represent in real world sound, it's easier to detect the nuts when you run across them.


----------



## chef8489

bigshot said:


> No, I think he is a nut in the sense that he manufactures differences that he could never hear in a controlled listening test in a million years. Nutty audiophiles are ones that worry about theoretical sound more than actual sound.
> 
> Check out the two AES seminar videos in my sig file. I think you'd find them interesting. They come with links to the test files so you can hear for yourself. If you understand what the specs and numbers represent in real world sound, it's easier to detect the nuts when you run across them.


He wont like it because it does not backup his purchases.


----------



## skwoodwiva

GrussGott said:


> if by "nut" you mean "actually has understands why cables matter", I agree!
> (and it's not just cables, it's everything, but it's also cables)
> 
> I also posted lots of info on why that is, which I didn't think would work, and it didn't.
> ...


Thank you, I may not be up to date on many digital details, but I HEARHEAR(!) that it often sounds like (rap.


----------



## gregorio

GrussGott said:


> [1] if by "nut" you mean "actually has understands why cables matter", I agree!
> [2] Anyway, you can read about Darko making fun of you guys here, in case you wanted to know what experts think versus, say, you guys.



1. No, by "nut" I would mean someone who either has pretty much no understanding of how cables work or has a very good understanding which he chooses to misrepresent for some personal gain/agenda.
2. I am interested in knowing what experts think, can you post a link to one? And by expert I mean an actual expert in digital audio and how it works, not an expert in "fake news" and using it to con audiophiles. 

I get it, you've been conned and either you're in denial or even worse, you haven't yet even realised you're being conned. Either way, this is the science forum and your personal ability to recognise that you're being scammed is not relevant, the facts are. Quoting "fake news" or marketing BS to backup your apparent belief that you are not being conned is not acceptable here and of course, it's actually counter productive, as relying on fake news demonstrates the exact opposite, that you are in fact being conned! Oh dear ...

G


----------



## GrussGott

bigshot said:


> No, I think he is a nut in the sense that he manufactures differences that he could never hear in a controlled listening test in a million years. Nutty audiophiles are ones that worry about theoretical sound more than actual sound.



Just FYI, I live in and work in Silicon Valley with engineers who design this stuff for a living and they're using this thread as comic relief ... in a "never have so few said so much that meant so little" kind of way.

Anyway, just thought you might want to know.

*For the OP *(and non bits-are-bits religious)*:*

*Do cables matter?*
Yes, but in very complex and non-intuitive ways

*Why?
PART 1 - What is Digital?
PART 2 - Are Bit just Bits?
Cables, Bits, and Noise: How Cables Can Make A Sound Difference

Should I sweat buying a cheapie USB cable?*
Probably not

*Should I buy an unobtanium USB cable?*
Probably not

*How should I prioritize my audio spend?*
Headphones
Amp
DAC
source
cables


----------



## chef8489

GrussGott said:


> Just FYI, I live in and work in Silicon Valley with engineers who design this stuff for a living and they're using this thread as comic relief ... in a "never have so few said so much that meant so little" kind of way.
> 
> Anyway, just thought you might want to know.
> 
> ...


Yet you cant come up with any other sources.


----------



## colonelkernel8

GrussGott said:


> Just FYI, I live in and work in Silicon Valley with engineers who design this stuff for a living and they're using this thread as comic relief ... in a "never have so few said so much that meant so little" kind of way.
> 
> Anyway, just thought you might want to know.
> 
> ...



Any of those "Silicon Valley engineers" care to have a Skype chat? I'd love to embarrass them.


----------



## gregorio (Mar 26, 2018)

GrussGott said:


> I live in and work in Silicon Valley with engineers who design this stuff for a living ...



So, that's a "no" then, thanks for playing!

G

Edit: Do you honestly think that repeat posting links to "fake news" is either acceptable in this sub-forum or somehow gains you credibility?


----------



## bigshot

I’m sitting here having tea with the Queen Of England and she can’t stop laughing at how funny you are. She just blew tea out her nose she was laughing so hard!


----------



## Glmoneydawg (Mar 26, 2018)

bigshot said:


> I’m sitting here having tea with the Queen Of England and she can’t stop laughing at how funny you are. She just blew tea out her nose she was laughing so hard!


The Queen would never take tea at 2:30!...thats how i know you're fibbing.....unless you are visiting Windsor Castle...time difference is about right...ok its possible...now I'm embarrassed...say hi to her majesty for me.


----------



## Glmoneydawg

GrussGott said:


> Just FYI, I live in and work in Silicon Valley with engineers who design this stuff for a living and they're using this thread as comic relief ... in a "never have so few said so much that meant so little" kind of way.
> 
> Anyway, just thought you might want to know.
> 
> ...


There are different kinds of engineers my friend....i get the feeling the ones in here work in and know the audio thing pretty well....having said that i have to agree with your spending priorities with a digital setup,but i doubt anyone would disagree with them.


----------



## castleofargh

I'm a big believer in cables, I have some in front of me. I even use them. ^_^

guys. show how an expensive cable does that better than fine 10$ USB cable using measurements, and we'll all agree to the fact or at least we'll be interested in the conditions surrounding the measurements. in any case you'd have everybody's attention. obviously if the magnitude of the changes at the DAC's output is way down well below -100dB, don't expect everybody to agree that 400$ or more on a USB cable is a good investment. that money would probably have done more for fidelity if put somewhere else in the audio chain. but at least better specs, better resulting signal fidelity, those are element of evidence we can all stand by.
they mean something. 

a dude saying "I know what I'm hearing" on the internet, sorry but it's really not worth much of anything. we can keep the kitty fight and pretend we're talking science, but the reality is always the same. why should we trust a random guy who's ignorant enough about his own human condition to assumes that a subjective impression from poorly done listening test, defines objective fidelity? that's not how you define or measure audio fidelity. end of story. 

I don't doubt that throwing money endlessly to manufacture the best USB cable can result in better performances than stuff from a batch of 10$ USB cables. I also don't doubt for a second that it would be measurable. now would that be at levels relevant for humans listening to music? well it's another story. 
 given that I already arrive at the limits of measured resolution for my gears using random cheap USB cables both for output and input, I have no reason to suspect any issue that a fancy USB cable would solve thanks to mega shielding, or some signal filtering that should never be a cable's job in the first place. maybe other people with other gears end up in different situations, and maybe super fancy cable came and saved the day for someone. I don't know because it seems to be really hard to find megabuck USB cable advocates who also are able and equipped for high fidelity measurements. some could even find the correlation interesting. as if it was easier to see the truth of USB cable goodness when we don't own any measurement gear. but I will refrain from making a claim about that, we all know the danger or assuming causality from cherry picked correlations.


----------



## bigshot

Audiophool logic: You don't know if fancy cables will make a difference unless you've done a super scientific test with each and every cable in the world!


----------



## skwoodwiva (Mar 27, 2018)

bigshot said:


> Audiophool logic: You don't know if fancy cables will make a difference unless you've done a super scientific test with each and every cable in the world!


You know wire physics is funny, when I first heard from an audiophile "freak" years ago that the silver plated copper conductors souned harsh in the top end, really what a nut.

It is cheap to be had teflon salvage wire. Well after comparing this interconnect that I made to a pair of pure silver, again homemade, I found statement true.
Yet it was only after upgrading all wire, everywhere to silver that I was sure. I put the old plated wire on one channel & the pure stuff on the other. The system was worth 18000.00 retail in '95. All Sony ES bought on sale.  Go figure....

https://www.head-fi.org/threads/introduction-first-post-semi-review-of-sony-mdr1a-b.874614/


----------



## gregorio

skwoodwiva said:


> You know wire physics is funny...



No it's not, it's been well known for a century or more. Do you honestly think you've learned something from a home made cable that generations of physicists, engineers and corporations don't know about? If so, let's see the evidence.

G


----------



## skwoodwiva

gregorio said:


> No it's not, it's been well known for a century or more. Do you honestly think you've learned something from a home made cable that generations of physicists, engineers and corporations don't know about? If so, let's see the evidence.
> 
> G


So I take it you disbelieve my testamony?
I just want to understand you surly


----------



## colonelkernel8

skwoodwiva said:


> You know wire physics is funny, when I first heard from an audiophile "freak" years ago that the silver plated copper conductors souned harsh in the top end, really what a nut.
> 
> It is cheap to be had teflon salvage wire. Well after comparing this interconnect that I made to a pair of pure silver, again homemade, I found statement true.
> Yet it was only after upgrading all wire, everywhere to silver that I was sure. I put the old plated wire on one channel & the pure stuff on the other. The system was worth 18000.00 retail in '95. All Sony ES bought on sale.  Go figure....
> ...


Literally impossible. Sorry pal. The whole silver and copper thing bringing out “bright” or “warm” sound is a silly joke related to the color of the metals themselves.


----------



## colonelkernel8

skwoodwiva said:


> So I take it you disbelieve my testamony?
> I just want to understand you surly


I know your testimony is incorrect because it is physically impossible.


----------



## skwoodwiva

colonelkernel8 said:


> I know your testimony is incorrect because it is physically impossible.


Dogmatic?
Hmm....


----------



## colonelkernel8

skwoodwiva said:


> Dogmatic?
> Hmm....


The opposite of dogmatic.


----------



## skwoodwiva

colonelkernel8 said:


> The opposite of dogmatic.


Please do not reply to me anymore.
Ty.


----------



## gregorio (Mar 27, 2018)

skwoodwiva said:


> So I take it you disbelieve my testamony?



Are you really asking me if I believe your testimony against the testimony and hard evidence of generations of engineers and physicists? This isn't a bible forum, your testimony is worthless here. Now if you've got some hard evidence that's a different matter but be aware that an extraordinary claim, which contradicts decades of accepted knowledge, requires exceptional evidence!

G


----------



## colonelkernel8

skwoodwiva said:


> Please do not reply to me anymore.
> Ty.


Now THAT’S dogmatic.


----------



## skwoodwiva

colonelkernel8 said:


> Now THAT’S dogmatic.


You got it...


----------



## castleofargh

let's not lose ourselves for no reason. your anecdote didn't even concern USB cables right? if so, let's not turn this into an all cable war topic.


----------



## bigshot

Shall I say that all properly designed and manufactured cables sound exactly the same for the purposes of hooking up a home stereo system now?


----------



## bfreedma

bigshot said:


> Shall I say that all properly designed and manufactured cables sound exactly the same for the purposes of hooking up a home stereo system now?



Only if I can bring back the whalebat.


----------



## amirm

bigshot said:


> Shall I say that all properly designed and manufactured cables sound exactly the same for the purposes of hooking up a home stereo system now?


This is one of those unhelpful chants we should refrain from making.  "Properly designed?  What is there to design in a cable?  "Properly manufactured?"  You mean have the wires connected versus not?

And what do you mean by "all?"  Based on what data and experience?

Best to say that you think they all sound the same if they work and have nothing else to contribute to the topic.


----------



## castleofargh

bfreedma said:


> Only if I can bring back the whalebat.


the whalebat was collateral damage. with rabid posts all around, I had to put it down just in case. certainly was a sad day, losing such a majestic creature.



bigshot said:


> Shall I say that all properly designed and manufactured cables sound exactly the same for the purposes of hooking up a home stereo system now?


grrrrr


----------



## colonelkernel8 (Mar 28, 2018)

amirm said:


> This is one of those unhelpful chants we should refrain from making.  "Properly designed?  What is there to design in a cable?  "Properly manufactured?"  You mean have the wires connected versus not?
> 
> And what do you mean by "all?"  Based on what data and experience?
> 
> Best to say that you think they all sound the same if they work and have nothing else to contribute to the topic.


No. Just, no. We don’t need to account for the 0.1%. I'm with Bigshot here. “Properly designed” is if there is a standard; built at or above that standard. So correct impedance, shielding, twisted pair, length, other design requirements, etc. “Properly manufactured” is the connectors fit snugly, the insulation, shielding, and internal conductors are intact, all electrical joints are connected with solder or mechanically fastened.

Edit: let’s go with AES standards for everything.


----------



## castleofargh

Spoiler: off topic on topic of the off topic. now discuss dem USB cables!



the consequence is that because the claim was global and definitive, the guy experiencing that 0.1% will conclude that we're all full of crap. and he'll be right because our model doesn't seem to allow his experience to exist.
just saying proper gear and proper use, that means nothing to most audiophiles as they know close to nothing about electronic or electricity. to them proper gear is expensive gear and proper use is plugging the right shape of cable into the holes, or whatever concept of synergy related to subjective impression of the sound. in the end it comes down to us setting up unclear elitist(for a very ignorant hobby!!!!!!!)conditions so that we can always end up on our feet and say we were right. it works, but it's not helping anybody.

I'd be fine with a simple "should sound the same". and I've been playing this game for a while with bigshot. it doesn't abandon the idea that cables aren't supposed to do fancy night and day analog signal processing. but it also doesn't tell a lie or a truth under conditions most people won't understand. it leaves the door open so that people who experience a weird situation, or even people who can't test for crap or made up differences in their head, can see the "should" and wonder what went wrong. I'd rather they can do that instead of becoming a crusader for the "cable is life" religion, because bigshot doesn't like to bother with small exceptions.
 we chose to care about for facts and follow something of a low key scientific method in this section. then let's do it and offer inclusive explanations instead of closing doors because most of the time under proper conditions, that door is useless. we're good at being super specific and detailed when we disagree with a claim, if we have double standards when we do agree, why should anybody trust us?
I get that simple black&white models are good for proselytism, I just need to look at audio marketing to confirm that it works amazingly well. but simplified black&white models aren't good for truth. maybe I'm mistaken, and convincing audiophiles anyway we can should take priority because like anybody else, we know that we're right and that it's for their own good. but I have much more basic ambitions, I hope to learn stuff, and have a place where I don't have to triple fact check everything I read.

wow I went deep and pretentious real fast. engage countermeasure: I went to a seafood disco last night, and pulled a mussel.


----------



## amirm

colonelkernel8 said:


> No. Just, no. We don’t need to account for the 0.1%. I'm with Bigshot here. “Properly designed” is if there is a standard; built at or above that standard. So correct impedance, shielding, twisted pair, length, other design requirements, etc. “Properly manufactured” is the connectors fit snugly, the insulation, shielding, and internal conductors are intact, all electrical joints are connected with solder or mechanically fastened.
> 
> Edit: let’s go with AES standards for everything.


It is not accounting for .1% but just the talking points themselves which are annoying and unhelpful.  No one on the other side likes to read stuff like that.  And no one on our side learns a thing about audio/technology by reading it either.  Let's leave talking points for PR people.  If we have nothing useful to say, let's not say it at all.  The "all" part just adds insult to injury.


----------



## bigshot (Mar 28, 2018)

I'd be happy to write a review of the usefulness of you if you'd like to invite me!



amirm said:


> What is there to design in a cable?



I'm sure there are plenty of people here willing to speak up and answer that one too!

"Proper" is a cable that does its job. There is no excuse for a cable that doesn't do its job. If you can name a cable that is audibly inferior, please do and warn people in big red letters to avoid it. Show evidence that it has an AUDIBLE DEFECT. Don't just show that another one is better in theory. What matters is what we hear. If there are audibly inferior products out there, name them. Prove they are inferior. Don't just talk about them in theory. Prove it. Anything else is semantic BS that isn't helpful to anyone.

I'm not asking you to do something that I'm afraid to do. I got banned from this forum for a couple of years by proving the emperor had no clothes. Do that and I'll be your fan instead of the thorn in your side. But don't give me semantics and bluster and ego. That doesn't work with me.


----------



## Joe Bloggs

There are people who hear differences in cables, and people who don't, and never shall the twain meet. 

For my part I hear and play with differences in so many things in audio that science agree will make a difference that I wonder why everybody else seem to be exclusively limiting themselves to tweaking things that science say can't make a difference on one side, or yelling at people that nothing makes a difference on the other side (because of the limitation imposed by the first side).


----------



## colonelkernel8 (Mar 28, 2018)

Joe Bloggs said:


> There are people who hear differences in cables, and people who don't, and never shall the twain meet.
> 
> For my part I hear and play with differences in so many things in audio that science agree will make a difference that I wonder why everybody else seem to be exclusively limiting themselves to tweaking things that science say can't make a difference on one side, or yelling at people that nothing makes a difference on the other side (because of the limitation imposed by the first side).



"There are people who are misled, lied to, and conned into hearing differences in cables, and people who know better and don't appreciate people lying to make a profit off of the gullible and in the process, destroying the integrity of their hobby."

That's what it boils down to. I don't like my hobby being turned into a bazaar of bull full of mass-dampened, sand-filled cables, quantum manipulators, magic pebbles, and pieces of wood with magical little metal cups I stick to the wall.


----------



## skwoodwiva

colonelkernel8 said:


> "There are people who are misled, lied to, and conned into hearing differences in cables, and people who know better and don't appreciate people lying to make a profit off of the gullible and in the process, destroying the integrity of their hobby."
> 
> That's what it boils down to. I don't like my hobby being turned into a bazaar of bull**** full of mass-dampened, sand-filled cables, quantum manipulators, magic pebbles, and pieces of wood with magical little metal cups I stick to the wall.


You know what baby & bath water means?


----------



## bfreedma

skwoodwiva said:


> You know what baby & bath water means?



Instead of the non-sequiturs, can you post the results of the study you reference?


----------



## colonelkernel8

skwoodwiva said:


> You know what baby & bath water means?



Do you know what being "full of crap" means?


----------



## skwoodwiva

bfreedma said:


> Instead of the non-sequiturs, can you post the results of the study you reference?


Cannot find it. Tried many times. Why am I here.
This info & all I that goes on here will be spread all over audiophile forums by me.


----------



## colonelkernel8

skwoodwiva said:


> Cannot find it. Tried many times. Why am I here.
> This info & all I that goes on here will be spread all over audiophile forums by me.


So your goal is to spread incoherence and lies. Neat philosophy.


----------



## bfreedma

skwoodwiva said:


> Cannot find it. Tried many times. Why am I here.
> This info & all I that goes on here will be spread all over audiophile forums by me.




I figured - can't produce the hard evidence.   So your purpose here is to reference studies you can't produce then publish our responses to "audiophile forums"?   

The very definition of a troll.


----------



## skwoodwiva (Mar 28, 2018)

bfreedma said:


> I figured - can't produce the hard evidence.   So your purpose here is to reference studies you can't produce then publish our responses to "audiophile forums"?
> 
> The very definition of a troll.


Hmm I hold my tongue at such rashness. Not just hornet
I am appealing to other like me to find the study or the truth.


----------



## bfreedma

skwoodwiva said:


> Hmm I hold my tongue at such rashness. Not just hornet
> I am appealing to other like me to find the study or the truth.




No, you're just making word salads as you troll.   I doubt it will go on much longer.


----------



## gregorio

skwoodwiva said:


> Hmm I hold my tongue at such rashness.



You are making statements of fact without any hard evidence, how is that not rash? And why therefore are you not holding your tongue? It's patently obvious this quote is untrue, so why post it? Do you think we're too stupid notice something so patently obvious? Who are you used to conversing with who would be stupid enough to fall for such an untruth? You're making bfreedma's conclusion pretty much impossible to disagree with!

G


----------



## gregorio

Joe Bloggs said:


> There are people who hear differences in cables, and people who don't, and never shall the twain meet.



Do you have any hard evidence that "there are people who hear differences" or only anecdotal evidence that some people think they hear differences? All the better evidence I've seen (DBTs for example), indicates that there are no people who hear differences in cables? If there are no people who hear real/actual differences, how could the twain ever meet?

G


----------



## bigshot

There are people who think they hear differences in cables. And if they refuse to do any sort of controlled listening test and don’t bother to figure out how cables work, they can maintain their misconceptions for a long time.


----------



## Joe Bloggs

Lol I was being loose with my terms... 
Suggestion: can @castleofargh or anybody move threads like these out of Sound Science into their rightful places such as Cables (DBT-free), Computer Audio (Fidelizer thread), etc.? If nobody is allowed to take a firm stance against topics like these, maybe at least one could make a gesture to show what is Sound Science and what isn't, simply by the positioning of threads?  People can gush about the benefits of these topics in those places without intervention from the people here for the most part.


----------



## skwoodwiva

gregorio said:


> Do you have any hard evidence that "there are people who hear differences" or only anecdotal evidence that some people think they hear differences? All the better evidence I've seen (DBTs for example), indicates that there are no people who hear differences in cables? If there are no people who hear real/actual differences, how could the twain ever meet?
> 
> G





gregorio said:


> Do you have any hard evidence that "there are people who hear differences" or only anecdotal evidence that some people think they hear differences? All the better evidence I've seen (DBTs for example), indicates that there are no people who hear differences in cables? If there are no people who hear real/actual differences, how could the twain ever meet?
> 
> G


http://www.geocities.ws/jonrisch/


----------



## colonelkernel8 (Mar 28, 2018)

skwoodwiva said:


> http://www.geocities.ws/jonrisch/



Geocities...this ought to be good.

Unsurprisingly, there's nothing on that website of value. Just bull tweaks and nonsense. All the links are dead, considering it's 15 year old content at a minimum.


----------



## skwoodwiva

colonelkernel8 said:


> Geocities...this ought to be good.
> 
> Unsurprisingly, there's nothing on that website of value. Just bull**** tweaks and nonsense.


Phenomenal


----------



## gregorio

skwoodwiva said:


> http://www.geocities.ws/jonrisch/



Huh? Maybe you didn't understand the question? Sorry but I don't know how to make this question any simpler for you to understand, all I can do is repeat it: "_Do you have any hard evidence that there are people who hear differences_"?

G


----------



## skwoodwiva

gregorio said:


> Huh? Maybe you didn't understand the question? Sorry but I don't know how to make this question any simpler for you to understand, all I can do is repeat it: "_Do you have any hard evidence that there are people who hear differences_"?
> 
> G


It is just hard to find there.

Look here
https://db.audioasylum.com/cgi/search.mpl?forum=cables&searchtext=Interconnects

Now his testimony is there I will have to dig if you do not find it.


----------



## skwoodwiva

skwoodwiva said:


> It is just hard to find there.
> 
> Look here
> https://db.audioasylum.com/cgi/search.mpl?forum=cables&searchtext=Interconnects
> ...





skwoodwiva said:


> It is just hard to find there.
> 
> Look here
> https://db.audioasylum.com/cgi/search.mpl?forum=cables&searchtext=Interconnects
> ...


https://db.audioasylum.com/cgi/search.mpl?forum=cables&searchtext=Harsh+silver

More like what you may want?


----------



## colonelkernel8

skwoodwiva said:


> https://db.audioasylum.com/cgi/search.mpl?forum=cables&searchtext=Harsh+silver
> 
> More like what you may want?



Quoting the same old tired tropes is a waste of time. "Harsh silver" became a self-perpetuating myth in the same way so many other audiophile myths are formed.

Silver, as a material, CAN NOT alter the frequency response of a cable or whatever it's attached to. It just can't. It doesn't inherently have some low frequency blocking series-capacitive property. No metal does. I don't know how else to help you with this. I don't have a spectrum analyzer handy to show this to you, but I assure you a silver cable and copper cable would have a perfectly flat frequency response from 0 to 20 kHz, and far beyond that into likely the MHz (depending on the insulation, yes, the insulation matters in the MHz).


----------



## skwoodwiva

colonelkernel8 said:


> Quoting the same old tired tropes is a waste of time. "Harsh silver" became a self-perpetuating myth in the same way so many other audiophile myths are formed.
> 
> Silver, as a material, CAN NOT alter the frequency response of a cable or whatever it's attached to. It just can't. It doesn't inherently have some low frequency blocking series-capacitive property. No metal does. I don't know how else to help you with this. I don't have a spectrum analyzer handy to show this to you, but I assure you a silver cable and copper cable would have a perfectly flat frequency response from 0 to 20 kHz, and far beyond that into likely the MHz (depending on the insulation, yes, the insulation matters in the MHz).


Do I have to spoon feed?
https://db.audioasylum.com/cgi/search.mpl?forum=cables&searchtext=Smearing


----------



## colonelkernel8 (Mar 28, 2018)

skwoodwiva said:


> Do I have to spoon feed?
> https://db.audioasylum.com/cgi/search.mpl?forum=cables&searchtext=Smearing



Do you know what "science" is? Evidence? How the scientific method works? I've heard all of this nonsense in the past. A million people could tell me that silver cables are "brighter", but then that same million people would be wrong. Dead wrong.

The "skin" effect that this so-called phase "smear" would require massively thick conductors laid out over MILES to be noticeable.


----------



## gregorio

skwoodwiva said:


> [1] It is just hard to find there. Look here https://db.audioasylum.com/cgi/search.mpl?forum=cables&searchtext=Interconnects
> [2] Now his testimony is there I will have to dig if you do not find it.



1. No, there's nothing there either.

2. It's a very simple question, how come you are unable to understand it? The question was NOT "do you have any testimony that there are people who hear differences", the question was (YET AGAIN!): "Do you have any hard evidence that there are people who hear differences". Do you really not understand the question, was Bfreedma's conclusion spot on?

G


----------



## colonelkernel8 (Mar 28, 2018)

gregorio said:


> 1. No, there's nothing there either.
> 
> 2. It's a very simple question, how come you are unable to understand it? The question was NOT "do you have any testimony that there are people who hear differences", the question was (YET AGAIN!): "Do you have any hard evidence that there are people who hear differences". Do you really not understand the question, was Bfreedma's conclusion spot on?
> 
> G


That's not evidence that people actually hear those differences. We JUST had someone claim that they heard differences between two 100% IDENTICAL files (prior to knowing they were identical, mind you) in your other thread. Does that not suggest the fallibility of human hearing?


----------



## Whazzzup

For some reason i have been drawn to the chord company sarum array usb cable. Course there are only testimonials, reviews, and a whopper cost, but as I researched they are mid market. Can you believe it. There are 10,000$ 3 ft cables being sold out there, course no proof of effects..
Well thought id throw that out there get the juices flowing.


----------



## skwoodwiva

gregorio said:


> 1. No, there's nothing there either.
> 
> 2. It's a very simple question, how come you are unable to understand it? The question was NOT "do you have any testimony that there are people who hear differences", the question was (YET AGAIN!): "Do you have any hard evidence that there are people who hear differences". Do you really not understand the question, was Bfreedma's conclusion spot on?
> 
> G


Gregorio, concider this as maybe not what you want but a better than averageaverage testimony.

"
You know wire physics is funny, when I first heard from an audiophile "freak" years ago that the silver plated copper conductors souned harsh in the top end, really what a nut.

It is cheap to be had teflon salvage wire. Well after comparing this interconnect that I made to a pair of pure silver, again homemade, I found statement true.
Yet it was only after upgrading all wire, everywhere to silver that I was sure. I put the old plated wire on one channel & the pure stuff on the other. The system was worth 18000.00 retail in '95. All Sony ES bought on sale. Go figure....

https://www.head-fi.org/threads/introduction-first-post-semi-review-of-sony-mdr1a-b.874614/

" 
The nut was Jon Risch.
 Now I do know of a study done in 2001 proving hearing acuity in .1% of males. This is what I cannot find w/o going to the LA times.


----------



## colonelkernel8

skwoodwiva said:


> Gregorio, concider this as maybe not what you want but a better than averageaverage testimony.
> 
> "
> You know wire physics is funny, when I first heard from an audiophile "freak" years ago that the silver plated copper conductors souned harsh in the top end, really what a nut.
> ...



Oh Jesus...you're in the wrong forum man. Wire physics aren't "funny". They're nearly perfectly well understood (I hesitate to say nearly as I know audiophools will latch on to this, but no one knows 100% about anything).

This is how soundly I believe in science: We could find the absolute pinnacle of this coveted 0.1% of males you keep rambling on about, and if he told me he heard differences between copper and silver wire in the same setup, I'd still know he was wrong. Completely wrong.


----------



## Joe Bloggs

At this point would anyone mind if a mod deleted all responses by SS regulars but moved this thread to the cables forum?


----------



## bigshot (Mar 28, 2018)

I discovered a great feature of this forum software. If you click on a poster's name, it pops up a window with some options in it. If you click on "ignore", you don't have to wade through the posts of a person who posts blather purely for their own benefit. Skwoodwiva, if you continue to speak without listening and keep trying to dominate the conversation with pointless comments, I (and probably many other people here) will start ignoring you.

You are serving an audience. We are that audience. Don't piss us off. Consider this a shot across the bow.


----------



## colonelkernel8

bigshot said:


> I discovered a great feature of this forum software. If you click on a poster's name, it pops up a window with some options in it. If you click on "ignore", you don't have to wade through the posts of a person who posts blather purely for their own benefit. Skwoodwiva, if you continue to speak without listening and keep trying to dominate the conversation with pointless comments, I and probably many other people here will start ignoring you.
> 
> You are serving an audience. We are that audience. Don't piss us off. Consider this a shot across the bow.


Sorry bigshot, I should’ve let it go and ignored the guy.


----------



## Joe Bloggs

Assuming this topic is worth continuing at all, somebody could show him what a science paper featuring DBT on a audio phenomenon that was actually proven to make a difference looks like. That would be a start...


----------



## skwoodwiva

Joe Bloggs said:


> At this point would anyone mind if a mod deleted all responses by SS regulars but moved this thread to the cables forum?


Good idea


----------



## colonelkernel8

Joe Bloggs said:


> Assuming this topic is worth continuing at all, somebody could show him what a science paper featuring DBT on a audio phenomenon that was actually proven to make a difference looks like. That would be a start...


I doubt he knows what DBT stands for, let alone would he take its results to heart.


----------



## colonelkernel8

Joe Bloggs said:


> At this point would anyone mind if a mod deleted all responses by SS regulars but moved this thread to the cables forum?


Throwing this back to the echo chamber of disreality would be counter productive.


----------



## bigshot (Mar 28, 2018)

They don't move dumb comments from sound science to the cables forum. They only move dumb comments from the cable forum to sound science. Funny how that works!



Joe Bloggs said:


> Assuming this topic is worth continuing at all, somebody could show him what a science paper featuring DBT on a audio phenomenon that was actually proven to make a difference looks like. That would be a start...



Have you seen any indication that he's listening to anything that people say to him? I sure haven't. I think he is earning a good old fashioned Amish style shunning.


----------



## Joe Bloggs

colonelkernel8 said:


> I doubt he knows what DBT stands for, let alone would he take its results to heart.



I assume that also means you've concluded this topic is not worth continuing at all--unless you love Chinese fire drills and mutually administered self-torture


----------



## castleofargh (Mar 29, 2018)

Joe Bloggs said:


> Lol I was being loose with my terms...
> Suggestion: can @castleofargh or anybody move threads like these out of Sound Science into their rightful places such as Cables (DBT-free), Computer Audio (Fidelizer thread), etc.? If nobody is allowed to take a firm stance against topics like these, maybe at least one could make a gesture to show what is Sound Science and what isn't, simply by the positioning of threads?  People can gush about the benefits of these topics in those places without intervention from the people here for the most part.


it wasn't originally in Sound Science, I even stopped posting in it because ego was vastly dominating the conversation like it too often does. then a while after it got moved here and I actually complained at the time. in part because I didn't want to have to handle so many people who judge everything with sighted tests and unwarranted self confidence in an objectivity focused sub section. but here we are.


@skwoodwiva I've been letting things go because you're new, but this Sound Science sub section of the forum where you amazingly made 2/3 of your posts, is mainly focused on measurements and blind tests. measurements because they're still the most effective way to quantify physical variations, and blind tests because they're the most unbiased listening test we have so far. also we insist on blind test because they are a forbidden subject in the rest of the forum. so at least this place has to take a stand for what is right.
now, if all your posts will keep being about making wild claims without evidence, calling obvious facts false without providing anything objective info that would suggest you're right, and rely on your feelings to "demonstrate" things, well, sorry but you need to go do that in another section of the forum. one that values personal impressions and doesn't mind empty claims and sighted tests. you can see that people are reaching the end of their rope in a few topics of the section because of your posts, and I'll soon have to start deleting posts and at least locking you out of a few topics just to be able to put them back on track. please show me that you're not just trolling on purpose, and mind what you're posting from now on in a science oriented section. measurements, testimonies from blind tests, information on electrical behaviors inside a conductor. information on USB protocols. not how grandma felt in the other room last time I used my new USB cable.

and for others, as always, please don't feed the trolls too much. ignore if it's dumb, report if it's insulting. there isn't a lot more to do within the TOS.


----------



## skwoodwiva

castleofargh said:


> it wasn't originally in Sound Science, I even stopped posting in it because ego was vastly dominating the conversation like it too often does. then a while after it got moved here and I actually complained at the time. in part because I didn't want to have to handle so many people who judge everything with sighted tests and unwarranted self confidence in an objectivity focused sub section. but here we are.
> 
> 
> @skwoodwiva I've been letting things go because you're new, but this Sound Science sub section of the forum where you amazingly made 2/3 of your posts, is mainly focused on measurements and blind tests. measurements because they're still the most effective way to quantify physical variations, and blind tests because they're the most unbiased listening test we have so far. also we insist on blind test because they are a forbidden subject in the rest of the forum. so at least this place has to take a stand for what is right.
> ...


While I will chew on more of this message,
Please edit the usb thread as you like I am not the op.
I will get back to you later
Ty


----------



## Whazzzup (Mar 28, 2018)

Jeez missed it, see what happens when you unsubscribe. Has anyone heard this chord Sarum array USB? Or better tested this...


----------



## colonelkernel8

Whazzzup said:


> Jeez missed it, see what happens when you unsubscribe. Has anyone heard this chord Sarum array USB? Or better tested this...


They make them as expensive as this to prevent testing...I’m sure it performs just as well as any other factory made USB cable.


----------



## gregorio (Mar 29, 2018)

skwoodwiva said:


> Gregorio, concider this as maybe not what you want but a better than averageaverage testimony. ...



Firstly, why should I consider that as "better than average testimony"? "Testimony" is typically information formally given under oath, the information you've provided therefore hardly even qualifies as testimony, let alone better than average testimony! And secondly, even if it really were better than average testimony, how does that answer the question? How can I make it any clearer that the question was *NOT* "do you have any TESTIMONY that there are people who hear a difference" but do you have any "HARD EVIDENCE"?

We are left with only two possible conclusions: 1. You don't appear to know what the word "testimony" means but far more importantly (and relevantly!), you do not even know the difference between something someone posts on the internet and "hard evidence" or 2. You are trolling.

Please try to understand what castleofargh has posted. I don't hold out much hope though, as you have repeatedly failed to understand even my simple question, despite the fact that I've further clarified it to the point that it could not be any simpler!!



colonelkernel8 said:


> We JUST had someone claim that they heard differences between two 100% IDENTICAL files (prior to knowing they were identical, mind you) in your other thread. Does that not suggest the fallibility of human hearing?



It's not just a claim, it's a well known, scientifically studied effect and an easily demonstrated fact! And btw, even prior knowledge of the fact the files are 100% identical still does not prevent us from "hearing" an obvious difference. If you have not already seen it, please watch this 3 min video.
Notice in the previous sentence I put the word "hearing" in quotation marks, that's because "hearing" is not entirely the correct term, "perceiving" would be a more accurate term. Referring back to the video, we are always hearing "Baa" but we are not always perceiving "Baa". Appreciating the difference between hearing and perceiving is absolutely essential at every level, not just in regards to cables and other audio equipment but even to the fundamental level of what music actually is. Unfortunately, many audiophiles do NOT appreciate this difference, they typically believe that perception, hearing and the actual physical properties of sound waves are all exactly the same thing. If instead they did appreciate this difference, then most/all of the audiophile snake oil would simply not exist and neither would disputes such as this thread!

G


----------



## NorCal (Mar 29, 2018)

What I don't understand is, why someone wouldn't just play one, (or more), of the games on Head-Fi, to reach their 100 posts ... instead of seemingly trolling  here. Maybe I'm wrong, but that's what I kept thinking as I read all of these posts today. Seems like a lot of effort on his/her part.


----------



## rule42

gregorio said:


> Firstly, why should I consider that as "better than average testimony"? "Testimony" is typically information formally given under oath, the information you've provided therefore hardly even qualifies as testimony, let alone better than average testimony! And secondly, even if it really were better than average testimony, how does that answer the question? How can I make it any clearer that the question was *NOT* "do you have any TESTIMONY that there are people who hear a difference" but do you have any "HARD EVIDENCE"?
> 
> We are left with only two possible conclusions: 1. You don't appear to know what the word "testimony" means but far more importantly (and relevantly!), you do not even know the difference between something someone posts on the internet and "hard evidence" or 2. You are trolling.
> 
> ...


----------



## Yuurei

colonelkernel8 said:


> Silver, as a material, CAN NOT alter the frequency response of a cable or whatever it's attached to. It just can't. It doesn't inherently have some low frequency blocking series-capacitive property. No metal does.



Are we still talking about USB cable or any cable in (in our case) audio setup? I'm not attacking or anything I'm just reall curious about it


----------



## rule42

I think seeing the McGurk Effect for the first time was a huge wow moment for me and I thank @gregorio for the introduction and for keeping on bringing it up. Implications are huge and has helped me throw a load of preconceptions out of the window (plus saving me a heap of money and reading a lot about psychoacoustics). Thanks.The brain is a wonderful thing.


----------



## skwoodwiva

Yuurei said:


> Are we still talking about USB cable or any cable in (in our case) audio setup? I'm not attacking or anything I'm just reall curious about it


Right you be on this, that I truly my fault & way off topic.
I lost track as to non op thread.


----------



## skwoodwiva (Mar 29, 2018)

NorCal said:


> What I don't understand is, why someone wouldn't just play one, (or more), of the games on Head-Fi, to reach their 100 posts ... instead of seemingly trolling  here. Maybe I'm wrong, but that's what I kept thinking as I read all of these posts today. Seems like a lot of effort on his/her part.


Good call I am too ernest to be a troll, I call you Sherlock.
But the one type of silver on one channel vs pure on the other should not have caused harshness to be one one side of the room...


----------



## chef8489

skwoodwiva said:


> Good call I am too ernest to be a troll, I call you Sherlock.
> But the one type of silver on one channel vs pure on the other should not have caused harshness to be one one side of the room...


You are saying that with speakers in a room that just changing one wire to one set of speakers you hear harsheness out of that side of the room. Give me a break. Get real.


----------



## skwoodwiva

chef8489 said:


> You are saying that with speakers in a room that just changing one wire to one set of speakers you hear harsheness out of that side of the room. Give me a break. Get real.


It was all the interconnects & ~ 30 feet each


----------



## chef8489

skwoodwiva said:


> It was all the interconnects & ~ 30 feet each


The more you post the more we relise how useless your posts are. I really think you should stay away of the sound science forum as was sugested earlier if you think you can hear a difference in cables while a systen with speakers are playing in a room. soundwaves would bounce off walls and mix. Even if the  room was soundproofed the soundwaves would mix in the room. You could not isolate such a subtle difference even if one existed with both speakers playing in the same room.


----------



## bigshot

skwoodwiva said:


> But the one type of silver on one channel vs pure on the other should not have caused harshness to be one one side of the room...



It's a good idea if you are going to throw ideas out there to know whether they'd actually work that way. In this case, I don't have to ask you whether you've actually tried this. I know you're making it up. You may actually believe that it works this way, so it doesn't mean you're lying. But it does mean that the amount you talk has a tendency to overrun the amount you have to say. You really should make an effort to listen and understand what people are saying to you. You appear to fixate on ideas and not be able to communicate well with others.


----------



## amirm

skwoodwiva said:


> But the one type of silver on one channel vs pure on the other should not have caused harshness to be one one side of the room...


Unfortunately you can be convinced that is the case even if the sound has not changed.  Next time you perform this type of test have a loved one switch the cables, or not every day.  Have them keep a log and you do the same as to whether you think there is a silver cable or not.  At the end of the seven days, see what percentage you got right.  In other words, make the test blind so that your perception of what is what does not impact the test outcome.

To motivate your loved one and you to do the test, I will offer you $50 Amazon gift card to perform the test.  Doesn't matter what the outcome is.  You will get the $50.  Just post the two logs when you are done and I will send you the gift card.  Deal?


----------



## bigshot

...this isn't going to end well.


----------



## Glmoneydawg (Mar 29, 2018)

bigshot said:


> ...this isn't going to end well.


Not so fast bud......50$ will buy cables both made of the same material..its a win/win for him


----------



## skwoodwiva

amirm said:


> Unfortunately you can be convinced that is the case even if the sound has not changed.  Next time you perform this type of test have a loved one switch the cables, or not every day.  Have them keep a log and you do the same as to whether you think there is a silver cable or not.  At the end of the seven days, see what percentage you got right.  In other words, make the test blind so that your perception of what is what does not impact the test outcome.
> 
> To motivate your loved one and you to do the test, I will offer you $50 Amazon gift card to perform the test.  Doesn't matter what the outcome is.  You will get the $50.  Just post the two logs when you are done and I will send you the gift card.  Deal?


Great idea, but I have an easier one.
I was going to make a nice cable for my Sony cans. So I make 3.
1)Silver, 
2)plated silver on 1 channel & silver on other.
3) the Opposite.
I could ID them by marks on plug shaft. My wife could swithing.
The money mean nothing it is not my motivation...


----------



## Glmoneydawg

Glmoneydawg said:


> Not so fast bud......50$ will buy cables both made of the same material..its a win/win for him


Ok...possibly not


----------



## skwoodwiva (Mar 29, 2018)

amirm said:


> Unfortunately you can be convinced that is the case even if the sound has not changed.  Next time you perform this type of test have a loved one switch the cables, or not every day.  Have them keep a log and you do the same as to whether you think there is a silver cable or not.  At the end of the seven days, see what percentage you got right.  In other words, make the test blind so that your perception of what is what does not impact the test outcome.
> 
> To motivate your loved one and you to do the test, I will offer you $50 Amazon gift card to perform the test.  Doesn't matter what the outcome is.  You will get the $50.  Just post the two logs when you are done and I will send you the gift card.  Deal?


Deal!
I did not realize who you were. Forgive me for messing your thread.
I also requested a new thead but still in SS. Title
"YourYour UN" 's requested wire testing.
Ok?
It will start with your request..


----------



## Glmoneydawg

skwoodwiva said:


> It was all the interconnects & ~ 30 feet each


I should preface this by saying i have some nice cables...they have nice tight connections are good at rejecting 60hz line hum for my phono section and they look cool...and i could afford them lol,but i have no illusions about improved sound quality....if your system 
draws 20amps(it doesn't) you could argue for a heavy gauge power cord to reduce voltage drop with heavy amp draw.Rfi and hum rejection would also be legimate in some circumstances,but none of these things will actually make a system sound harsh...these things are also all in the analog domain!In the digital domain none of this applies as i'm sure previous posters have pointed out.Trust us here.


----------



## skwoodwiva

Glmoneydawg said:


> I should preface this by saying i have some nice cables...they have nice tight connections are good at rejecting 60hz line hum for my phono section and they look cool...and i could afford them lol,but i have no illusions about improved sound quality....if your system
> draws 20amps(it doesn't) you could argue for a heavy gauge power cord to reduce voltage drop with heavy amp draw.Rfi and hum rejection would also be legimate in some circumstances,but none of these things will actually make a system sound harsh...these things are also all in the analog domain!In the digital domain none of this applies as i'm sure previous posters have pointed out.Trust us here.


All this I know...
But OK.
I did not apply in my original test anyway.


----------



## Glmoneydawg (Mar 29, 2018)

skwoodwiva said:


> All this I know...
> But OK.
> I did not apply in my original test anyway.


Good as i have now exposed myself to ridicule from@bigshot for having fancy cables


----------



## skwoodwiva

Glmoneydawg said:


> Good as i have now exposed myself to ridicule from bigshot for having fancy cables


I love ridicule


----------



## Glmoneydawg

skwoodwiva said:


> I love ridicule


Keep watching then....its comming lol


----------



## skwoodwiva

Glmoneydawg said:


> Keep watching then....its comming lol


Ohh I know, some troll stealing the stage in SS, WT...


----------



## castleofargh (Mar 29, 2018)

I'd still love it if we could stick to USB cables. all the other possible situations of using an electrical cable have little to do with USB cables and the way a USB signal is manipulated. next we'll argue about high voltage wires and how a USB cable should have the same thickness.
the purpose of a USB cable is to be good at its USB cable job. who cares about other cables with other standards and requirements.


----------



## bigshot

Which sounds better? RCA connectors, BNC connectors or HDMI plugs?

just kidding!


----------



## skwoodwiva (Mar 29, 2018)

castleofargh said:


> I'd still love it if we could stick to USB cables. all the other possible situations of using an electrical cable have little to do with USB cables and the way a USB signal is manipulated. next we'll argue about high voltage wires and how a USB cable should have the same thickness.
> the purpose of a USB cable is to be good at its USB cable job. who cares about other cables with other standards and requirements.


I asked in a report to create a new SS thread starting with the OPs request of me.
Are you in a posiition to mske sure that happens?


----------



## skwoodwiva

bigshot said:


> Which sounds better? RCA connectors, BNC connectors or HDMI plugs?
> 
> just kidding!


There are military tests, they have reverted to tin. Gold in not the end all. For reliability anyway. Sonics will not be much effected by such a block of metal. I know it was a joke.
But did you know that?


----------



## Glmoneydawg (Mar 29, 2018)

1


bigshot said:


> Which sounds better? RCA connectors, BNC connectors or HDMI plugs?
> 
> just kidding!


Carefull bud.....you may have to cut down the tallest tree in the forest with.....a herring lol(i know castleofargh will get this)....not so sure about anyone else...oh well


----------



## skwoodwiva (Mar 29, 2018)

amirm said:


> Unfortunately you can be convinced that is the case even if the sound has not changed.  Next time you perform this type of test have a loved one switch the cables, or not every day.  Have them keep a log and you do the same as to whether you think there is a silver cable or not.  At the end of the seven days, see what percentage you got right.  In other words, make the test blind so that your perception of what is what does not impact the test outcome.
> 
> To motivate your loved one and you to do the test, I will offer you $50 Amazon gift card to perform the test.  Doesn't matter what the outcome is.  You will get the $50.  Just post the two logs when you are done and I will send you the gift card.  Deal?


I can easily get the plated silver cheap, however if anyone knows a source of silver TFE wire please post it.
I am not sure of the best gauge for 24 ohm cans. I bet 24 ga would be plenty for a 6 footer.
Also is a shield necessary with a cell phone? With interconnects a braid was ok but a double ground is needed for a braid, 3 wires.


----------



## bigshot

Glmoneydawg said:


> not so sure about anyone else...oh well



me neither!


----------



## skwoodwiva

.


----------



## gregorio

skwoodwiva said:


> Also is a shield necessary with a cell phone?



Something like an iPhone for example, typifies the problem with audiophilia. Do we judge "audiophile grade" by cost/purchase price or by audible fidelity? If it's the former, then an iPhone is pretty much the exact opposite of audiophile grade because the total cost of all it's audio components, DAC, amp and interconnects, is probably no more than about $20-$30. If it's the latter though, then iPhones aren't just hi-fi, they're summit-fi, it doesn't get any better than an iPhone! The latter is what we judge by in this sub-forum, the former in most others. The "systems on a chip" in cell phones produce considerable interference and shielding is therefore necessary but they achieve adequate shielding and summit-fi performance without containing any hundred or thousand dollar interconnects/cables!

G


----------



## skwoodwiva

gregorio said:


> Something like an iPhone for example, typifies the problem with audiophilia. Do we judge "audiophile grade" by cost/purchase price or by audible fidelity? If it's the former, then an iPhone is pretty much the exact opposite of audiophile grade because the total cost of all it's audio components, DAC, amp and interconnects, is probably no more than about $20-$30. If it's the latter though, then iPhones aren't just hi-fi, they're summit-fi, it doesn't get any better than an iPhone! The latter is what we judge by in this sub-forum, the former in most others. The "systems on a chip" in cell phones produce considerable interference and shielding is therefore necessary but they achieve adequate shielding and summit-fi performance without containing any hundred or thousand dollar interconnects/cables!
> 
> G


Right.
So I will braid 2 grounds & the signal wire, hence a braid.
I will use some ofc Kimber 19Ga and some old tfe 18ga plated silver
Thanks
Like my avitar?


----------



## castleofargh

off topic




skwoodwiva said:


> .


I love Lord of the Ring. it's impressive how they made those actors look small for the hobbit roles.


----------



## KLK2A1

castleofargh said:


> off topic
> 
> 
> 
> I love Lord of the Ring. it's impressive how they made those actors look small for the hobbit roles.



That's Python's Holy Grail.  Not Hobbits, but the knights who say Ni!


----------



## castleofargh

KLK2A1 said:


> That's Python's Holy Grail.  Not Hobbits, but the knights who say Ni!


sorry friend I meant to make a lame joke, not to set up a trap. have a good look at my nickname.


----------



## Glmoneydawg

castleofargh said:


> sorry friend I meant to make a lame joke, not to set up a trap. have a good look at my nickname.


the dangers of a sense of humour.


----------



## KLK2A1

castleofargh said:


> sorry friend I meant to make a lame joke, not to set up a trap. have a good look at my nickname.




Gotcha.


----------



## Glmoneydawg

KLK2A1 said:


> Gotcha.


Nice!


----------



## GrussGott (Mar 31, 2018)

bigshot said:


> Jitter is horse poop. Anyone who talks about jitter is talking purely in theory. Jitter as it exists in consumer audio products is an order of magnitude below the threshold of audibility. The only purpose for jitter is so one audibly transparent product can convince you to spend more instead of buying a cheaper audibly transparent product. It's marketing. Show me a product with audible levels of jitter.



Here's another engineer who designs high end audio products for a living...

He explains  jitter for you ...



What jitter is and why it's audible (and how you could hear it for yourself) ...



And how and why - AND WHERE in the music you can hear it

*Most people only need to watch this video, but you need to watch them all*


----------



## colonelkernel8 (Mar 31, 2018)

lol. This guy is so full of crap. “I’d speculate drummers would care about jitter”. Really. A drummer is going to pick up on “timing issues” measured in picoseconds? You only need a tiny amount of understanding and this guy’s bull falls apart like a house of cards. @GrussGott since you don’t have any engineering understanding, let me make it abundantly clear that while this guy sounds like he knows what he’s talking about, he absolutely doesn’t. On top of that, he has the damn oscilloscope on the bench behind him. Who builds a DAC and then listens to it to see if it’s performing correctly? No one. Engineers will measure it first. He couldn’t hear the jitter, not in a million years. He expected the 50 cent clock multiplier chip from SiLabs to cause a problem, so he heard a problem.

Edit: Ah he works for PS Audio. SAY NO MORE.

Final edit: he also completely disproves your point by suggesting that everything before the asynchronous buffer *doesn’t matter*. I agree with him here. I disagree with his ridiculous exaggeration of 0.2 ps of jitter has on a DAC.

Final final edit: “what I always look for is are people’s toes tapping to the music, that’s a sign there’s lower jitter”. Hahahahhahahahahahhahahhahahahahhahahahahahhahahaha. Ok this guy is pointless.


----------



## Glmoneydawg

colonelkernel8 said:


> lol. This guy is so full of ****. “I’d speculate drummers would care about jitter”. Really. A drummer is going to pick up on “timing issues” measured in picoseconds? You only need a tiny amount of understanding and this guy’s bull**** falls apart like a house of cards. @GrussGott since you don’t have any engineering understanding, let me make it abundantly clear that while this guy sounds like he knows what he’s talking about, he absolutely doesn’t. On top of that, he has the damn oscilloscope on the bench behind him. Who builds a DAC and then listens to it to see if it’s performing correctly? No one. Engineers will measure it first. He couldn’t hear the jitter, not in a million years. He expected the 50 cent clock multiplier chip from SiLabs to cause a problem, so he heard a problem.
> 
> Edit: Ah he works for PS Audio. SAY NO MORE.
> 
> ...


But he has an oscilloscope!...and a giant beard....he looks very smart!...Hawaiian shirt is a nice touch also.


----------



## GrussGott (Mar 31, 2018)

colonelkernel8 said:


> @GrussGott since you don’t have any engineering understanding



Well not "no understanding" ... I went to college for EE and worked as an engineer for 10 years, but not designing consumer audio equipment.  Nowadays, living here in silicon valley, I mostly just talk to engineers with decades of experience designing audio electronics for things like Cisco IP phones, smart phones, and that kind of stuff.

Anyway, they all tell me to a person that if I'm going to get music out of my laptop or similar source it should be in this order:

*Ethernet=I2S >>>>>>  spdif  >>>>>>>>>>>>>>>>>>>>>>>> USB > TOSLINK*

They describe USB as a firestorm of electrical interference and say toslink would've been great due to no electrical noise (galvanic isolation), except apparently toshiba ruined it with crappy connectors and now it's lucky if it can reliably get 96/24.  They say the same is true with spdif in that it has separate clocks, data, etc, but they went and multplexed it all together.  I understand when they explain it, but I have no deep understanding myself.

Anyway, since you claim to, how many decades of experience designing consumer audio equipment do you have again?

Because honestly the only people I've heard of that disagree with the audio engineers I talk to that actually design, test, and build stuff are you people.

So just curious on the practical product experience you're basing your opinions on ... and why you're not a billionaire!


----------



## colonelkernel8

GrussGott said:


> Well not "no understanding" ... I went to college for EE and worked as an engineer for 10 years, but not designing consumer audio equipment.  Nowadays, living here in silicon valley, I mostly just talk to engineers with decades of experience designing audio electronics for things like Cisco IP phones, smart phones, and that kind of stuff.
> 
> Anyway, they all tell me to a person that if I'm going to get music out of my laptop it should be in this order:
> 
> ...


These engineers should know that Toslink and SPDIF are the same thing, just transmitted over a different medium, and that calling USB a “firestorm” of interference is a ****ing lie, and that Ethernet and USB are both packet-based asynchronous formats and are completely different than I2S or Toslink/SPDIF. I2S is for transmission of PCM data between chips on a single board. There is no cable standard for I2S. “The I2S connection was not intended to be used via cables, and most integrated circuits will not have the correct impedance for coaxial cables.“ Wikipedia.

It doesn’t matter how many “decades” of consumer audio engineering experience I have, whichever engineers you’re talking to either don’t know what they’re talking about or you’ve made them up. Like I said, I’d be happy to Skype with these morons and embarrass them, hell, I’m calling them out personally to tell me how they decided upon that magical order of digital transmission formats.


----------



## colonelkernel8 (Mar 31, 2018)

GrussGott said:


> They describe USB as a firestorm of electrical interference and say toslink would've been great due to no electrical noise (galvanic isolation), except apparently toshiba ruined it with crappy connectors and now it's lucky if it can reliably get 96/24.



By the way, it’s optoisolation. Not galvanic. That’s the whole point of using an optical cable.

Oh look, proof with actual data! Shocking!
http://thewelltemperedcomputer.com/Intro/SQ/Toslink_Coax.htm


----------



## GrussGott

colonelkernel8 said:


> It doesn’t matter how many “decades” of consumer audio engineering experience I have ...



Ahhh ... so no training, no practical experience, aggressive idea beat downs, assumed infallibility ... yup, it's confirmed!

You're religious!

Cunning plan, setting up your church under the cover of "science" ... well at least your church has great parking!


----------



## colonelkernel8 (Apr 1, 2018)

GrussGott said:


> Ahhh ... so no training, no practical experience, aggressive idea beat downs, assumed infallibility ... yup, it's confirmed!
> 
> You're religious!
> 
> Cunning plan, setting up your church under the cover of "science" ... well at least your church has great parking!



Nice job deflecting. I’ve been an engineer for 10 years (if you count engineering school). I am relatively young.


----------



## castleofargh

in the end we have 3 main options: 
1/ we want improved measurements and improved fidelity. we don't care if it's audible, better is better. in such a case the one and only relevant data for a decision is to measure my system and check if every time I try new gears, I'm really getting improved fidelity. and not just the idea of better fidelity a marketing guy placed in my head. fidelity is a measure of how much change occurred in the signal, only a measurement in my playback chain can give the answer to "is this cable better?", "is this DAC better?"

2/ we care about what we can hear. in such a case the one and only relevant data is a blind test between the gears we're wondering about. we test them in conditions where only the sound is relevant(which is what a blind test really is about) and we learn if there is any difference for us specifically. when there is, we pick the one we prefer, or maybe we decide to measure them and pick the best? not very subjective but still fairly rational for components of a digital process. 

3/ the audiophile way. no measurement but talking about fidelity all day long. the fidelity that we quantify subjectively, because who cares about the meaning of fidelity. and I don't know what a listening test looks like, but I talk with certainty about minute variations I might have made up in my head, and I describe them as night and day different. 
it's the apogee of paradox, the most defective way to approach audio quality. as nothing is measured, we can never know if something is a problem and could be significantly improved. so of course when some marketing dude talks about an issue they just happen to know how to fix with the stuff they sell, we wonder. do I have that issue? should I "fix it"? and because I measure nothing and can't do a proper listening test to save my life, why would that doubt go away? instead it will probably grow stronger as time passes until I decide to get the magical device to fix my main problem called: insecurity. 


we can make up hypotheses all day long about why we need special stuff or how we can be special ourselves and have special needs. we can pretend that stuff down at -120dB is stopping us from enjoying music properly. imagination has no limit. but without proper controls, objective or subjective, we're bound to live with doubt.


----------



## GrussGott

castleofargh said:


> iwe can make up hypotheses all day long about why we need special stuff or how we can be special ourselves and have special needs. we can pretend that stuff down at -120dB is stopping us from enjoying music properly. imagination has no limit. but without proper controls, objective or subjective, we're bound to live with doubt.



And we can also believe that:

(1.) We know all that is measurable
(2.) Our beep-boop boxes are capable of measuring all that we know
(3.) We are perfect interpreters of those measurements.

Of course none of that is true, which is why most of this thread is religion not science.

Science strives to find answers for _*observable phenomena, *_not discount that which is not explainable as not observed.

Colonel8 up there gets a pass for being a kid - I was a know-it-all arsehat when I was his age too, but for the rest of the people here?

This is supposed to be a science forum which means when something is observed we don't dismiss it, but attempt to find an answer - the absence of our ability to explain observation does not equal an absence of the observed ... which is the very definition of doctrinal region and  what 99% of people on this "science" forum toss out: doctrine.

The only reason I post here is for the innocent; in the hopes they don't take all the pseudo-science claptrap doctrine as reality.

Cables make a difference and there are lots of reasons we think we know for that, but there's a lot we don't know.

Nothing is settled, and that's the scientific state-of-the-art right now.


----------



## colonelkernel8 (Apr 1, 2018)

GrussGott said:


> And we can also believe that:
> 
> (1.) We know all that is measurable
> (2.) Our beep-boop boxes are capable of measuring all that we know
> ...


I am not a know-it-all arsehat, but this is subject matter that I am well versed in.

When you observe something, you don’t dismiss it, no. You attempt to find why you observed such a thing, and that observation isn’t limited to our very, very limited senses. So if measurements using equipment far more sensitive and repeatable than your biological senses are prove you didn’t observe what you thought you did, then that is that, you didn’t truly observe it. It becomes a psychological question, one that is well studied, and indeed, observed. Some audiophiles start at the wrong end and try to suggest that minutiae like jitter and the crystalline structure of wire affect the sound but are never able to measure audible differences. This is the opposite of science.

Measurements have not shown that cables make any kind of audible change. Thus, your subjective opinion is null and void. Throwing your hands in the air and saying “well I guess it’s just a mystery, but I observed it!” is promoting the very clap-trap pseudoscience you claim we preach.


----------



## castleofargh

GrussGott said:


> And we can also believe that:
> 
> (1.) We know all that is measurable
> (2.) Our beep-boop boxes are capable of measuring all that we know
> ...


I suggest to measure or to listen. apparently you do want to believe there is a third path that isn't the way I described it. which path is it?

so here is my mind blowing concept. if we really care about *sound*, we should test sound and only sound. I know it's a lot to take in. that of course implies blind testing. if you know another way please propose it because I don't. 
IMO going to switch the cable myself, cable that I bought because I already hoped at the time that it would alter the sound(hey there preconception!). cable I picked because it was (strike the unneeded mention) pretty, expensive, had some technology I was told about by a guy who knows a guy who's a serious audiophile. then going to sit in my chair, grab a glass of coca cola(I take serious drugs), and trying to find out if I can hear the differences I'm positively dying to hear at this point. well I'm not sure we can honestly call that a *listening* test. sound seems to be coming to me with a lot of non audio baggage. 

if something is obvious for me, but when I try to find it again in a blind test, it becomes really hard or sometimes just impossible. I don't conclude that I'm always right and that blind testing sucks. I admit that I exaggerated the difference in my head or simply made it up.  so instead of who has the ear of science, I'd argue that we just have a vastly different idea of what defines an *observable phenomena* in sound.

oh and BTW, if you know of any audible change in sound that can be confirmed under test but cannot be measured, please tell me all about it. because I can't think of anything like that.


----------



## bigshot (Apr 1, 2018)

The thing that a lot of audiophiles seem to miss is that measurements are just half the story. Comparing numbers without relating measurements to actual real world listening conditions is what gets people to double down over and over again on "Improvements" they can't actually hear. It really helps to play with an equalizer and a SPL meter and a sound editing program to learn what all those numbers sound like. What do the various frequencies sound like and how do they contribute to the sound? How much is a dB? Is it a lot? A little? Is a dB difference at one frequency range the same as a dB difference at a different range? How high and low can humans hear? How much distortion is too much and what do different kinds of distortion sound like? If you know the answers to these questions, you can look at a chart showing the response of headphones or read manufacturer's specs and understand how it will impact you listening to your music in your home. If you haven't a clue, it's just abstract numbers.


----------



## gregorio (Apr 1, 2018)

GrussGott said:


> He explains jitter for you ...



Thanks for those videos, some of the funniest I've seen. That guy is a complete nutter!



GrussGott said:


> Well not "no understanding" ... I went to college for EE and worked as an engineer for 10 years, but not designing consumer audio equipment.



I've never designed consumer audio equipment. However, I've got 25 years experience of using high-end professional audio equipment and I've been lucky enough to work with a number of the world's best drummers and percussionists. The very best ones are incredibly accurate, sometimes to as little as a milli-second or so, it's really amazing. The problem here of course should be blatantly obvious, with jitter we're talking about the pico-second range of timing inaccuracy. That's several million times more timing accuracy than the world's best drummers. That guy in the videos you posted really is a nutter!



GrussGott said:


> (1.) We know all that is measurable
> (2.) Our beep-boop boxes are capable of measuring all that we know
> (3.) We are perfect interpreters of those measurements.
> 
> Of course none of that is true, which is why most of this thread is religion not science.



I'm afraid you have that backwards! It's completely irrelevant whether we know "all that is measurable" or whether we are "capable of measuring all that we know". Audio recording is measuring/converting, therefore, if we can't measure/convert it, then we CANNOT record it!! Since the dawn of recording technology we've measured/converted and recorded just two things; amplitude and frequency, that's it, nothing else! This is true with today's technology, the only difference being that we can measure/convert these two properties many times more accurately than could Edison. If there were something else out there that we don't know about or that we do know about but can't measure then it's irrelevant because we can't record it and it does not exist in any of the audio recordings to which you listen!!

As your preposition is irrelevant, your conclusion is nonsense!

G


----------



## bigshot

gregorio said:


> Thanks for those videos, some of the funniest I've seen. That guy is a complete nutter!



He's pretty popular with audiophools. He validates what they want to be told and he does it with a level of obfuscation that makes it seem believable if you don't understand how anything he's talking about works.


----------



## amirm

bigshot said:


> Comparing numbers without relating measurements to actual real world listening conditions is what gets people to double down over and over again on "Improvements" they can't actually hear.


Who gets to define real world for everyone else?  You?  I don't think so....


----------



## amirm

bigshot said:


> It really helps to play with an equalizer and a SPL meter and a sound editing program to learn what all those numbers sound like. What do the various frequencies sound like and how do they contribute to the sound? How much is a dB? Is it a lot? A little? Is a dB difference at one frequency range the same as a dB difference at a different range?


What is this doing in a thread about USB cables?  Anyone is saying it changes the frequency response?


----------



## amirm

gregorio said:


> 've never designed consumer audio equipment. However, I've got 25 years experience of using high-end professional audio equipment and I've been lucky enough to work with a number of the world's best drummers and percussionists. The very best ones are incredibly accurate, sometimes to as little as a milli-second or so, it's really amazing. The problem here of course should be blatantly obvious, with jitter we're talking about the pico-second range of timing inaccuracy. That's several million times more timing accuracy than the world's best drummers


There is a ton of confusion in these statements.  Jitter does NOT change the arrival accuracy of notes.  You are confusing very low speed changes with effects of jitter that occurs as modulation of music as a carrier.  

Audibility of jitter has been shown to be in nanosecond range.  Tell me that is impossible too because of what a drummer can or cannot do!

Anyway, best to stay on the top of USB cables before we give away the farm on audio objectivity due to lack of our understanding of other topics like jitter.


----------



## bigshot (Apr 1, 2018)

Jitter is inaudible because (aside from products that are defective or poorly designed) jitter levels are below the threshold of audibility even in the cheapest home audio products.

Sound is at its essence frequency and amplitude. If some sort of degradation is going to be audible, it has to manifest itself through frequency and amplitude.

I won't try to define the real world for you. You've already defined your world for yourself and nothing is going to change it.


----------



## amirm

bigshot said:


> Jitter is inaudible because (aside from products that are defective or poorly designed) jitter levels are below the threshold of audibility even in the cheapest home audio products.


As I said, no one better let you define what the "reality" means in audio. With no data from 99.999% of audio gear out there, you declared inaudibility of jitter in all of them?



bigshot said:


> Sound is at its essence frequency and amplitude. If some sort of degradation is going to be audible, it has to manifest itself through frequency and amplitude.


You are in dire need of understanding the difference between linear and non-linear systems.


----------



## colonelkernel8 (Apr 1, 2018)

amirm said:


> You are in dire need of understanding the difference between linear and non-linear systems.


You need to stop holding water for crackpot theories by obsessing over corner cases seen in less than 0.01% of audio setups. It’s utterly *insane* to believe that before we declare jitter to be almost always inaudible we need to measure every device on the planet. It’s disingenuous and unscientific.

Observe:



This is from the AES Damn Lies seminar in bigshot’s signature.


----------



## amirm

colonelkernel8 said:


> You need to stop holding water for crackpot theories by obsessing over corner cases seen in less than 0.01% of audio setups. It’s utterly *insane* to believe that before we declare jitter to be almost always inaudible we need to measure every device on the planet. It’s disingenuous and unscientific.


"Almost?"  0.01%?  Where did you get those numbers scientifically?  How many studies have you read in jitter audibility or think exists?






That graph hurts your case, not help.  For one, it is for a single, sinusoidal jitter.  You think that is the profile of jitter for all devices?

That aside, the chart shows that at 20 kHz, jitter contributions better be less than 1 nanoseconds.  You are willing to stipulate that as the requirement for audio reproduction for 16-bit samples? 

The only thing crackpot is for non-technical people to make grand technical statements.  Audio science is a beautiful thing.  No need to screw it up with lay intuition masquerading as the real thing.


----------



## colonelkernel8

amirm said:


> "Almost?"  0.01%?  Where did you get those numbers scientifically?  How many studies have you read in jitter audibility or think exists?
> 
> 
> 
> ...



Better be less than 1ns? Because -85 dB and 20 kHz is terribly audible? Please. Stop focusing on the minutiae that is only applicable to the science of signals in general to that of the audio realm. That is the real beautiful science here; signals, audio is but a tiny, almost inconsequential portion of it in the big picture, and one that is very, very easy in this day and age to get right.


----------



## bigshot (Apr 1, 2018)

amirm said:


> As I said, no one better let you define what the "reality" means in audio. With no data from 99.999% of audio gear out there, you declared inaudibility of jitter in all of them?



WHAT A GOLDEN OPPORTUNITY FOR YOU TO PROVE ME WRONG! 20ns is the threshold for jitter in music (or somewhere between -40dB and -50dB if you prefer that rating). Find me something that measures above those thresholds in the core frequencies and OH! What a donkey I will look like! Go! Run! Do it now! I'm waiting to be proven wrong! I'm patient.

In the meantime I'll chew on the logic of "just because no one has ever tested proving a phenomenon exits, that means we should assume it does exist until we have a chance to test everything." Will the sun rise in the East tomorrow... Hmmm... I don't know. We'll find out tomorrow. But by then tomorrow will be day after tomorrow and we'll have to wait to find out again!


----------



## gregorio

amirm said:


> [1] There is a ton of confusion in these statements. Jitter does NOT change the arrival accuracy of notes. You are confusing very low speed changes with effects of jitter that occurs as modulation of music as a carrier.
> [2] Audibility of jitter has been shown to be in nanosecond range. Tell me that is impossible too because of what a drummer can or cannot do!



1. I'm afraid the confusion is yours! I know jitter does not change the arrival time of notes, I was referencing several statements made in the video posted; regarding drummers' timing acuity and that drummers would therefore be particularly sensitive to the timing inaccuracy of jitter. Those statements were nonsense because as I stated, we're talking about several orders of magnitude difference in timing inaccuracy between jitter and what drummers are capable of, and because as you have stated, jitter does not change the arrival accuracy of notes anyway.

2. I can't remember the published study off the top of my head but jitter (in musical material) was demonstrated to be audibly detectable down to 200ns. That's a thousand or so times more jitter than I'd expect to see in even a cheap modern DAC. I don't think any of the test subjects were drummers though! 

G


----------



## ev13wt

amirm said:


> Who gets to define real world for everyone else?  You?  I don't think so....



Since you love reading, read this: https://en.wikipedia.org/wiki/Self-fulfilling_prophecy



I heard a song once on youtube that had lots of jitter (I was using my onboard soundcard). Sounded really bad. Bought the CD and a good DAC and now the song is clean sounding! Jitter is real.


----------



## chef8489 (Apr 17, 2018)

ev13wt said:


> Since you love reading, read this: https://en.wikipedia.org/wiki/Self-fulfilling_prophecy
> 
> 
> 
> I heard a song once on youtube that had lots of jitter (I was using my onboard soundcard). Sounded really bad. Bought the CD and a good DAC and now the song is clean sounding! Jitter is real.


It probably was not jitter but artifacts from bad encoding and possibly noise from pc.


----------



## ev13wt

chef8489 said:


> It probably was not jitter but artifacts from bad encoding and possibly noise from pc.



Yes. It was not jitter. Sorry for not marking my irony  I understand that the sentence in question could very well happen here


----------



## Arpiben

Noise from PC -> Bounded Uncorrelated Jitter (BUJ) then.


----------



## chef8489

Arpiben said:


> Noise from PC -> Bounded Uncorrelated Jitter (BUJ) then.


No. It can be anything from capicator whine to other noise or interfierence.


----------



## Arpiben

chef8489 said:


> No. It can be anything from capicator whine to other noise or interfierence.



Have no idea for the real reason and was half kidding only since, BUJ, a subcomponent of total jitter, is commonly caused by crosstalk coupling from adjacent interconnects on printed circuit boards (PCB). However, the characteristics of BUJ are still not well understood.
It is classified as uncorrelated due to being correlated to the aggressor signals and not
the victim signal or data stream.


----------



## Clive101

Where's everyone gone...?

66 pages and not a definitive answer......


----------



## donunus

There have been definitive answers except everyone has a different one lol. My short answer is yes they make a difference. Longer answer is just how much depends on the system's transparency and how good or bad the power situation is and also depends on how the dac transport/pc sends info to the dac. Bottom line is just get something better than el cheapo cables but don't spend more than 20% or so of the value of the entire system and lastly, just audition a few and have fun.


----------



## Clive101

+1


----------



## gregorio

Clive101 said:


> Where's everyone gone...?
> 66 pages and not a definitive answer......



Everyone's gone because there has been a definitive answer!

G


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## GrussGott (Jul 20, 2018)

gregorio said:


> Everyone's gone because there has been a definitive answer!



Which is to try them!

USB cables are oddly controversial - any reputable cable dealer allows at least a 30 day in-home trial with a 100% refund, so ...

*Here's the methodology:

(1.)* *Acquire: *Get new cables, and install
*(2.)* *Listen: *for ~3 weeks
*(3.)* *Revert: *swap back to old cables
*(4.)* *Decide:* Do you like the sound better or worse or no different?
*(5.)* *Take Action: *If the old cables sound worse, keep the new cables.   Done!

Some are compelled to intellectually prove to themselves they heard what they heard (oddly they always seem the most incapable of doing so).  This is like trying to prove why this week's grilled steak tastes better than last week's - who cares why?  Enjoy the steak, and repeat the methodology next week - if that's a glass of fecking merlot before the steak, drink the fecking merlot; no reason to assemble the junior science club.

The only test that can tell you anything is your ears, your system, your home.

The music experience is the True North.


----------



## bigshot

I just set up a quick level matched direct A/B switched comparison and know right away if it's worth it or not. I don't bother with comparing cables any more though. They always sound the same. If they did sound different, I'd be worried because a cable should be audibly transparent.


----------



## Phronesis

GrussGott said:


> Which is to try them!
> 
> USB cables are oddly controversial - any reputable cable dealer allows at least a 30 day in-home trial with a 100% refund, so ...
> 
> ...



Not a reliable methodology, IMO.  Very easy for expectations to shape perception with that methodology.


----------



## GrussGott

bigshot said:


> I just set up a quick level matched direct A/B switched comparison and know right away if it's worth it or not. I don't bother with comparing cables any more though. They always sound the same. If they did sound different, I'd be worried *because I believe a cable should be audibly transparent*.



FTFY


----------



## bigshot (Jul 20, 2018)

It is extremely inefficient to apply coloration using out of spec cables. Let’s say your system is a little bright in the 5kHz range. But it’s fine above 10kHz... You can buy a grossly inefficient cable that rolls off above 5 and it will solve your problem with 5-10, but you’re going to lose the top octave above 10 along with that.... or you simply use an equalizer to set an EQ curve precisely nailing your spike, cancelling it out. I know which way I’d prefer to address that problem!

If you have a cable that deliberately colors the sound, it’s by definition not going to present a balanced response. Cables don’t come with frequency response specs, which means you have to swap a bunch of them randomly until you find the one that solves your particular problem. If you have more than one source, each and every interconnect has to color the sound identically, so you're back to randomly swapping cables again until you find the one that matches.

Equalization is best applied at the very last stage before amplification using an equalizer so you can precisely fine tune to your desired curve. If you try to do it through random swapping of colored components upstream, it’s chaos and you’ll never get optimal sound. That’s why audio components are designed to perform to spec with a balanced response.

You may assume that I’m arguing against colored sound. I’m not. You can adjust your response any way you’d like. But don’t do it upstream with cables. Start with a calibrated balanced response, and then add your coloration at the end of the chain so everything is colored the same. That is just common sense.

I am willing to bet that every cable in your system would sound exact the same to you if you did a controlled comparison designed to remove expectation bias. Colored cables, DACs and amps are extremely rare. I’ve been trying to document the existence of one in the wild for years, and so far I haven’t found any. There are differences between how equipment measures, but to human ears they sound the same in a blind test.


----------



## GrussGott

Phronesis said:


> Not a reliable methodology, IMO.  *Very easy for expectations to shape perception* with that methodology.



Which is exactly why it's 100% reliable.  The only concern should be, "did that sound better"?  That's the whole point of buying any of this equipment in the first place.

What's your methodology to determine if your dinner tastes good?  You taste it.  If it's in a nice place, and looks great, and you love it do you care whether that was expectations or something else?

You shouldn't, as this is a leisure hobby unless you're a vendor.


----------



## bigshot (Jul 20, 2018)

If you consider placebo and expectation bias to be features that you are willing to pay extra for, feel free to do that. But if you’re going to extol the virtues of your delusion in sound science you aren’t going to get very far with it. We get to call you on the sloppiness of your logic and demand objective proof of what you say. If you refuse to do that, we get to dismiss you with a wave of the hand!

We are perfectly willing to let you be foolish if that’s how you want to be. To each his own. But don’t expect us to validate your foolishness.


----------



## GrussGott (Jul 20, 2018)

bigshot said:


> It is extremely inefficient to apply coloration using out of spec cables.



Definitely agree with that, yet to to be fair to the OP and the topic:


Cartma said:


> After trying a few USB cables I came across the Nordost Blue Heaven USB. This was t*he first USB cable that actually made an improvement in my system* instead of just sounding slightly different. I then decided to go all out and get the next step up.. the Nordost Heimdall 2 USB. This thing made as much, if not more of an improvement then a power cable or interconnect. *But the question is WHY?*



To your point, randomly trying USB cables until you find one that improves sound quality is (a.) annoying, and (b.) shouldn't be done for purposes of coloring sound.

For me, I don't worry about why, only if, and for me the AQ Carbon USB cable was the right mix of improvement and cost because I don't digital EQ at the source and anything lost between my laptop and DAC can never be recovered.


----------



## gregorio

GrussGott said:


> *(4.)* *Decide:* Do you like the sound better or worse or no different?
> [A] The only concern should be, "did that sound better"?



4. As USB cables do not carry any sound, what does judging sound have to do with anything?

A. If I buy a USB cable, whether for a DAC, a printer, external disk or whatever, the only concern should be: "Is this cable USB compliant, does it transfer data perfectly according to USB specifications?". Maybe your "only concern" is whether the USB cable for your printer, hard disk or other digital device "sounds better" but I certainly don't and I don't believe many others on the planet do either.

G


----------



## GrussGott (Jul 20, 2018)

bigshot said:


> But don’t expect us to validate your foolishness.



I don't expect anything from more from you (I don't know who "us" is - are you speaking for some formal committee?) than I do from any other poster on this forum: be realistic and honest about which hobby you're discussing.  And FYI the name-calling is probably not supported by posting rules as well just plain makes you sound so weak and fragile, which I'm guessing is the opposite of what you intend.

So back on topic, and to the OP's point, many experience an improvement with USB cables - but *explaining why takes us out of the realm of the leisure hobby of enjoying music, and into other pursuits that I believe are beyond this forum (and this hobby).*


----------



## GrussGott (Jul 20, 2018)

gregorio said:


> 4. As USB cables do not carry any sound, what does judging sound have to do with anything?



If you've tried an expensive USB cable in your system for a few weeks and didn't hear a difference, please let us know what your system setup is, and what cable you tried.

If you didn't, then just disclaim that your opinions are all amateur scientist guesses and theories that you have no actual practical experience with.


----------



## Triode User

gregorio said:


> 4. As USB cables do not carry any sound, what does judging sound have to do with anything?
> 
> A. If I buy a USB cable, whether for a DAC, a printer, external disk or whatever, the only concern should be: "Is this cable USB compliant, does it transfer data perfectly according to USB specifications?". Maybe your "only concern" is whether the USB cable for your printer, hard disk or other digital device "sounds better" but I certainly don't and I don't believe many others on the planet do either.
> 
> G



I dipped in to this thread before and then dipped out. But may I introduce the possibility that digital cables can also carry unwanted analogue noise which can get into the dac and colour the sound. I am familiar with the response that any properly designed and executed dac would filter out any such piggy backing noise but non the less the ideal world situation does not always exist in that respect. I have personally demonstrated the difference in sound due to different digital cables and have sold them to people who have handed over their hard earned cash on the basis of the demonstration. Obviously the ones and noughts are still the same ones and noughts so the actual music contained in the digital signal is unaltered. 

Just a thought.


----------



## GrussGott (Jul 20, 2018)

Triode User said:


> may I introduce the possibility that digital cables can also carry unwanted analogue noise



As well as the fact the any cable with a conductor is transmitting an analog signal; including when that analog signal is constructed in such a way as to represent digital, i.e., a square wave.

A perfect square wave is not possible so the equipment is configured to translate less than perfect square waves into digital like this:







but, if there's "noise on the wire" errors in translation can occur, changing the result to this:






The higher quality the quality of the transmission, the lower the probability of translation errors


----------



## gregorio

Triode User said:


> [1] But may I introduce the possibility that digital cables can also carry unwanted analogue noise which can get into the dac and colour the sound.
> [2] I am familiar with the response that any properly designed and executed dac would filter out any such piggy backing noise but non the less the ideal world situation does not always exist in that respect.
> [3] I have personally demonstrated the difference in sound due to different digital cables and have sold them to people who have handed over their hard earned cash on the basis of the demonstration.



1. No, ANY competently designed DAC (or other digital device) will reject any noise and only read the zeros and ones.There's always noise in a USB signal and going through a USB cable, regardless of whether it's cheap or expensive cable, either a USB DAC operates optimally with a USB signal or it's not a USB DAC. There are DACs for less than $80 which reject noise to many times below audibility, are audiophile DACs inferior to cheap DACs?

2. How many billions of digital devices are there in the world which are apparently ideal and do read USB data bit perfectly without the need for expensive cables?

3. Yep, it's amazing how people can be persuaded to part with their hard earned cash with a bit of marketing and suggestion. Loads of people handed over their extremely hard earned cash over 100 years ago for the original snake oil.

G


----------



## castleofargh

GrussGott said:


> Which is exactly why it's 100% reliable.  The only concern should be, "did that sound better"?  That's the whole point of buying any of this equipment in the first place.
> 
> What's your methodology to determine if your dinner tastes good?  You taste it.  If it's in a nice place, and looks great, and you love it do you care whether that was expectations or something else?
> 
> You shouldn't, as this is a leisure hobby unless you're a vendor.


the very idea that a USB cable would be picked by ear is pretty special IMO. it's born on the premise that USB cables will sound different, and then on the premise that your sighted experience is reliable. 
while the first one can probably happen for some reason sometimes(I'd expect that to be rare), the second one is just false. 

the good part about measurements is that they provide a clear quantification and let us know when the magnitude of variations are so small that it doesn't make much sense to look for them by ear. or when it does, it serves as evidence of the improvement. making our biased sighted impressions a little less suspicious. 



donunus said:


> There have been definitive answers except everyone has a different one lol. My short answer is yes they make a difference. Longer answer is just how much depends on the system's transparency and how good or bad the power situation is and also depends on how the dac transport/pc sends info to the dac. Bottom line is just get something better than el cheapo cables but don't spend more than 20% or so of the value of the entire system and lastly, just audition a few and have fun.


where is the evidence that cheap cables don't usually do the job? from which hat did you pull this 20% value?

the fact is that most people don't have to and don't care about USB cables at all. they get a DAC, plug the USB cable usually provided with it and never have to think about it again. people who buy several USB cables to try them, they're maniacs. I'm one of those somehow, and there isn't a single doubt that I've done more extensive testing of my cables than most audiophiles. but I can still see that it's not the usual behavior or what everybody should do. USB cables aren't bad enough often enough to warrant suspecting them de facto of failing at transparency.


----------



## Phronesis

GrussGott said:


> Which is exactly why it's 100% reliable.  The only concern should be, "did that sound better"?  That's the whole point of buying any of this equipment in the first place.
> 
> What's your methodology to determine if your dinner tastes good?  You taste it.  If it's in a nice place, and looks great, and you love it do you care whether that was expectations or something else?
> 
> You shouldn't, as this is a leisure hobby unless you're a vendor.



That sounds obvious and reasonable, but the problem is that our perceptions are actively constructed by our brains, and that process of perceptual construction is highly influenced by factors which operate at a subconscious level, and therefore almost entirely without our awareness.  One of those subconscious factors is our expectations.  For example, with your dinner analogy, if the same food is served in (A) a dingy restaurant with low prices and a reputation for mediocre food quality vs (B) a renowned restaurant with a celebrity chef, you and I and pretty much everyone else is very likely to believe that the food from restaurant B is clearly better, and we would be able to get quite specific about the ways in which it's better, even though it's exactly the same.  We may indeed enjoy the food in restaurant B better because of our expectations, but that enjoyment would derive from our expectations rather than the food actually being better.


----------



## gregorio

GrussGott said:


> [1] As well as the fact the any cable with a conductor is transmitting an analog signal; [1a] including when that analog signal is constructed in such a way as to represent digital, [1b] i.e., a square wave.
> [2] A perfect square wave is not possible so the equipment is configured to translate less than perfect square waves into digital like this:
> [3] The higher quality the quality of the transmission, the lower the probability of translation errors.



1. Clearly that is a false statement.
1a. Either it's an analogue signal OR it's an electrical signal that represents digital data, which is it?

2. A perfect square wave is not possible, which is why the USB protocol does NOT specify square waves!!

3. Already answered, "_How many billions of digital devices are there in the world which are apparently ideal and do read USB data bit perfectly without the need for expensive cables?_"

G


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## bigshot (Jul 20, 2018)

Edit: Isn't editing posts fun!



GrussGott said:


> I don't expect anything from more from you (I don't know who "us" is - are you speaking for some formal committee?)



You are in the Sound Science forum. You can compare your headphones to a good steak and your cable to a bottle of wine, but we don't have to pat you on the head and tell you that you are a clever boy.  We get to ask you what proof you have and we get to ask you to define your terms. This isn't just another forum on the list. The rules here are different and the regular posters here are different than the rest of the site. If you don't want to play by our rules, prepare to be paddled with science. I tend to think that isn't your strongest suit.



GrussGott said:


> many experience an improvement with USB cables - but *explaining why takes us out of the realm of the leisure hobby of enjoying music, and into other pursuits that I believe are beyond this forum (and this hobby).*



Your inability to reconcile your perceptual experience with rational thought isn't my problem, it's yours.

If I remember correctly, you've popped in here before, taken a snipe or two, and then ran off with your tail between your legs. How long before we get the pleasure of your exit again?


----------



## Triode User

gregorio said:


> 1. No, ANY competently designed DAC (or other digital device) will reject any noise and only read the zeros and ones.There's always noise in a USB signal and going through a USB cable, regardless of whether it's cheap or expensive cable, either a USB DAC operates optimally with a USB signal or it's not a USB DAC. There are DACs for less than $80 which reject noise to many times below audibility, are audiophile DACs inferior to cheap DACs?
> 
> 2. How many billions of digital devices are there in the world which are apparently ideal and do read USB data bit perfectly without the need for expensive cables?
> 
> ...



And that in a nutshell is why I lost patience in here before. Anyone with an ounce of an an enquiring mind might be interested in hearing the differences and then might want to investigate why those differences exist but instead we get the usual rote spewed out. I am personally insulted by 3 but it also betrays the limits of your understanding of audio systems in the real world.

Bye.


----------



## bigshot (Jul 20, 2018)

Triode User said:


> Anyone with an ounce of an an enquiring mind might be interested in hearing the differences and then might want to investigate why those differences exist.



Wait a minute... maybe I missed something... When was it proven that differences exist? Just claiming that there is a difference and refusing to test in a way that minimizes bias isn't enough to interest me. Maybe you're more easily interested. I'm very interested in investigating things that go against the established ideas of how things work, but only if they are proven to exist first. There are too many misconceptions and blatant lies for me to be interested in stuff people don't bother to prove.

So all that being said... can you point to a controlled test that indicates that USB cables sound different?


----------



## gregorio (Jul 20, 2018)

GrussGott said:


> [1] If you've tried an expensive USB cable in your system for a few weeks and [1a] didn't hear a difference, please let us know what your system setup is, and what cable you tried.
> [2] If you didn't, then just disclaim that your opinions are all amateur scientist guesses and theories that you have no actual practical experience with.



1. It doesn't take me 3 weeks to determine if a USB cable can pass a USB signal bit perfectly, just a few minutes.
1a. Again, what has hearing got to do with it, no human can hear digital data?

2. Huh? I've measured/assertaind numerous USB cables for bit perfect transfer and measurements are NOT opinions, guesses or theories! You're the one arguing opinions and not even amateur level science, nice try though! 



Triode User said:


> [1] And that in a nutshell is why I lost patience in here before.
> [2]  Anyone with an ounce of an an enquiring mind might be interested in hearing the differences and then might want to investigate why those differences exist but instead we get the usual rote spewed out.
> [3] I am personally insulted by 3 but it also betrays the limits of your understanding of audio systems in the real world.
> 
> [4] Bye.



1. Not sure I understand, you lost patience because we don't tolerate false statements here?

2. And anyone with two ounces of an enquiring mind might be interested to find out if there are any differences to hear in the first place! Stopping at one ounce isn't going to get you beyond all the marketing BS!

3. And I'm personally insulted by those so suckered by the marketing BS that they call others ignorant when they are the one's who are sadly deluded.

4. Seems like you might not be aware you're in the Sound Science sub-forum? ... Bye.

G


----------



## Triode User

gregorio said:


> 4. Seems like you might not be aware you're in the Sound Science sub-forum? ... Bye.



WAS in the Sound Science forum. If ever anything was misnamed it is this forum. As you say, bye.


----------



## gregorio

Triode User said:


> [1] WAS in the Sound Science forum.
> [2] If ever anything was misnamed it is this forum.
> [3] As you say, bye.



1. But you haven't provided any science or even anything resembling any science, all you've provided is your feeling that you've "lost patience", apparently that you only have an ounce of an enquiring mind.and an erroneous supposition of my understanding of audio systems, when you have absolutely no idea who I am or what my level of understanding is. 

2. How would you know?

3. Didn't you realise I was quoting you? But you're still here?!

G


----------



## bigshot

Triode User said:


> WAS in the Sound Science forum. If ever anything was misnamed it is this forum. As you say, bye.



BUH-BYE!


----------



## bigshot

GrussGott said:


> For me, I don't worry about why, only if, and for me the AQ Carbon USB cable was the right mix of improvement and cost because I don't digital EQ at the source.



If you just have one source it's OK to EQ at the source. But if you have multiple sources, it should be done at the last step before the amp. If the laptop is your only source, it's very easy to get parametric equalizers that work on laptops. They're a more precise way to either correct for imbalances or create coloration than using out of spec cables. There is no easier way to improve the sound of any system than proper EQing.

Understanding how digital audio works is the best way to be able to predict whether something will be an improvement or not. Random guesses end up with random results and ends up costing a lot more money than informed choices.

Working to eliminate bias by applying controls to your tests is the best way to know that your improvements are actually improvements. Bias is real. It's human. We all are subject to it. We shouldn't surrender to it.

Slackness in any of these things is fine for you if it meets your standards, but it doesn't mean that your techniques and impressions will be useful to anyone else. We all hear with the same sort of ears, but we aren't all subject to the same random luck or preconceived biases. I'm interested in having control over my system and that requires understanding and analysis. If you aren't interested in the science behind sound reproduction and you just want to roll the dice and plug something in and listen to music, feel free. But that isn't what this forum is about as I already explained.



GrussGott said:


> For me, I don't worry about why, only if, and for me the AQ Carbon USB cable was the right mix of improvement and cost because I don't digital EQ at the source and anything lost between my laptop and DAC can never be recovered.



If you've found a USB cable that sounds different than others, it isn't conveying more information. It's more likely that it's altering the information in some way. Any certified USB cable should pass signals bit perfect. They should all be perfect. If one isn't, it is probably defective in some way. Maybe you like the way that defect sounds, but I tend to think it's not that. I think it's bias.


----------



## GrussGott (Jul 20, 2018)

Phronesis said:


> *That sounds obvious and reasonable*, but the problem is that our perceptions are actively constructed by our brains,



That's because for anyone who's primary concern is listening to music, it's not only reasonable, but the only answer: try it, if you like the effect keep it.

Leisurely listening to music is all in what you perceive.

Sure, there are many here from the amateur science club who post-stoke each other for pleasure, but I prefer the music, and music lovers focus on it-does, not why-it-does.


----------



## GrussGott (Jul 20, 2018)

gregorio said:


> 1. It doesn't take me 3 weeks to determine if a USB cable can pass a USB signal bit perfectly, just a few minutes.
> 1a. Again, what has hearing got to do with it, no human can hear digital data?



It's ok to admit you have no practical experience thus everything you post is simply the theoretical guesswork of an amateur.


----------



## bigshot

GrussGott said:


> It's ok to admit you have no practical experience thus everything you post is simply the theoretical guesswork of an amateur.



Go away Herr Troll.


----------



## donunus

castleofargh said:


> where is the evidence that cheap cables don't usually do the job? from which hat did you pull this 20% value?
> 
> the fact is that most people don't have to and don't care about USB cables at all. they get a DAC, plug the USB cable usually provided with it and never have to think about it again. people who buy several USB cables to try them, they're maniacs. I'm one of those somehow, and there isn't a single doubt that I've done more extensive testing of my cables than most audiophiles. but I can still see that it's not the usual behavior or what everybody should do. USB cables aren't bad enough often enough to warrant suspecting them de facto of failing at transparency.



Last time I checked this hobby was about getting enjoyment out of one's system and if something sounds better to you then it is evidence enough but since we are in the sound science forum and I am not an engineer or scientist that can give you papers proving evidence then you win. All I know is that I can tell the difference and I enjoy the nuances that the better cables can give me. I'm out lol


----------



## castleofargh

GrussGott said:


> That's because for anyone who's primary concern is listening to music,
> 
> it's not only reasonable, but the only answer: try it, if you like the effect keep it.
> 
> ...


music lovers focus on whatever the hell they want, thank you very much.
if you want to push that line of thought, this amateur science club's main focus is on making sure that a listening experience is about the music and as little else as possible. in effect, we're more interested in music than many other audiophiles for we focus almost entirely on sound in our experiences.
and when we rely on measurements to make sure a USB cable does its job, we can effectively confirm that it's offering the expected high fidelity at the output of the DAC. those who don't care can go with their own gut feelings, but for those who care about fidelity, measurement is 





GrussGott said:


> not only reasonable, but the only answer



------------------------------------------------------------------------------------------------------









donunus said:


> Last time I checked this hobby was about getting enjoyment out of one's system and if something sounds better to you then it is evidence enough but since we are in the sound science forum and I am not an engineer or scientist that can give you papers proving evidence then you win. All I know is that I can tell the difference and I enjoy the nuances that the better cables can give me. I'm out lol


I have no issue with you or anybody else picking his gears however he likes for any possible reason. but the second someone insinuates that the difference is big enough to be audible in USB cables, I'm going to desire evidence and context. and that despite convincing arguments such as:






of course it's tricky to go do a proper blind test of USB cables, but if something is hard to prove, where I was raised it meant that people should not make claims about it.
I'll never deny a possibility for audible differences, I have my own bag of weird audio anecdotes. but I'm also conscious of all the people(me included) who will be sure they heard a difference in sighted tests when there wasn't one. so without any sort of evidence or measurement suggesting possible audibility, why should I assume that you're not one of them? 
so my typical reaction is to reject the claim until something convincing comes up to support it. for the same reason I'm also not a fan of people claiming there cannot be any difference caused by USB cables. no proper mean to prove something=no claim. if we could just follow that I'd be a happy camper.


----------



## donunus

Oh I have done a blind test but its really hard to prove to you unless you were here so this thread is actually useless lol


----------



## Brooko

GrussGott said:


> It's ok to admit you have no practical experience thus everything you post is simply the theoretical guesswork of an amateur.



The funny thing is that you have zero knowledge of Greg's credentials - yet you post this.

A few short facts for you:

Professional for decades
Musician and producer
Owns own professional studio
Grammy award winning
Perhaps you'd like to retract or apologise ?


----------



## GrussGott (Jul 21, 2018)

Brooko said:


> Perhaps you'd like to retract or apologise ?





riffrafff said:


> LOL.   Ah, the assumptions we make.


Why would I do that? According to your list, Greg is not

* A digital signals processing scientist
* A digital signals engineer
* A digital audio products designer
* not even an electrician

So sure, he's super qualified to comment on exactly what I said:  a non-scientific opinion on what system configurations he's used and what he heard.  that would be super useful!  As it is, if he's not heard a particular cable - has no practical experience with it - he's not qualified to discuss it ... and even if he has, he's not qualified to offer a scientific opinion.

Anybody think the name of this sub-forum is unrealistically aspirational?

anyway, if you tell me the music he produced I'll be sure to listen to it with a shiity USB cable as he intends.


----------



## riffrafff

Brooko said:


> The funny thing is that you have zero knowledge of Greg's credentials - yet you post this.
> 
> A few short facts for you:
> 
> ...



LOL.   Ah, the assumptions we make.


----------



## GrussGott

donunus said:


> Last time I checked this hobby was about getting enjoyment out of one's system and if something sounds better to you then it is evidence enough b*ut since we are in the sound science forum and I am not an engineer or scientist*



Don't let that stop you!  Nobody else here does.  "science"


----------



## Brooko

GrussGott said:


> Why would I do that? According to your list, Greg is not
> 
> * A digital signals processing scientist
> * A digital signals engineer
> ...



You did not answer my question about your assumption - which I shall state again plainly for all to see:



GrussGott said:


> It's ok to admit you have no *practical experience* thus everything you post is simply the *theoretical guesswork of an amateur.*



Please quote your own actual qualifications.


----------



## GrussGott (Jul 21, 2018)

Brooko said:


> You did not answer my question about your assumption - which I shall state again plainly for all to see: Please quote your own actual qualifications.



Sure brooks:
* My qualifications for my claim ("I bought this new gear, replaced my old gear, and heard better shiz") are that I bought some new gear, replaced the old gear, and actually used the new gear before I made a bunch of claims about it.   You know - actual practical empirical data on something.  Sciency people might call that "empirical assessment"

* As for my qualifications to spot amateur science club members, I have enough training and work experience in sciency stuff to know that anyone making for-reals-you-guys-trust-me theoretical claims about sufficiently complex systems for sure have no fecking idea what they're talking about, and the odds of them being experienced in science are about 5% and in being good at it are 0% (note: those are casual estimates)

*Back to the topic:*

Each person has to make a decision: are they willing to experiment and, if so, how much?

*With USB cables, many who try high quality USB cables (and/or decrapifiers) experience better sound quality:  What's going on?*

*(1.)* *Signals processing engineers will tell you* this is because the better the conductor (and shielding) the lesser the chance of transmission data errors (which doesn't mean no chance, far from it, and the effect may be small or non-existent depending on config)

*(2.)* *Others, including non-scientist/non-engineers* on this forum, claim conductor quality only must meet a minimum threshold to perfectly transmit an analog signal configured to represent digital data.  Further they would claim any improvement is SQ must be mass hallucination.

Personally I'm trusting my experience and the signals processing engineers, but it's up to each person.

If a non-scientist is a big believer in #2 and is doling out advice based on science, it seems only ethical to disclaim they have no education, training, or work experience in signals processing nor do they design digital audio products, nor do they have any practical experience with the cable(s) in question.

Just common courtesy, really.


----------



## Brooko (Jul 21, 2018)

GrussGott said:


> Sure brooks:
> * My qualifications for my claim ("I bought this new gear, replaced my old gear, and heard better shiz") are that I bought some new gear, replaced the old gear, and actually used the new gear before I made a bunch of claims about it.   You know - actual practical empirical data on something.  Sciency people might call that "empirical assessment"
> 
> * As for my qualifications to spot amateur science club members, I have enough training and work experience in sciency stuff to know that anyone making for-reals-you-guys-trust-me theoretical claims about sufficiently complex systems for sure have no fecking idea what they're talking about, and the odds of them being experienced in science are about 5% and in being good at it are 0% (note: those are casual estimates)
> ...



So you admit to having no professional experience - yet you slate others and try to discredit them without having the common courtesy to actually inquire what their actual level of expertise is. A simple respectful inquiry to Greg will get you all you need to know.  You also choose to rely on cable makers as experts in their fields without realising that in audio they have a very vested interest in what they are pushing.  Have you noticed that in the professional audio industry (ie the guys in the studios actually making the recordings etc), they use standards compliant well shielded cabling.  They do not use boutique mega $$$ stuff.  What does that tell you?  Their jobs rely on the quality of their output - yet you will not see Nordhost or any other boutique cabling in their studios.  Why?

The problem is that this IS the Sound Science section, and when people make claims it IS ok to question them and get more information.  Thats what science is about - being able to make assumptions based on repeatable empirical data to support it.  All that is asked here is for the data.  The common "well I hear a difference, so there" is not what this section is about.  Unless you're trying to troll - in which case its pretty easy to contact the Mods and have you permanently removed.  No-one wants that.

So respectfully - please produce your hypothesis, empirical repeatable data supporting it - and we can have an adult conversation.  If there is new data which shows evidence of boutique USB cables actually having an audible effect - I would be very interested.  So far I have seen no evidence.

Oh and the one part I missed - your method in coming to your conclusions.  Was the cable the only thing you changed?  Was the swapping sighted or unsighted?  Was it the same track?  Was it the same volume?  Was it the same listening position or in the case of headphones, the same pair, and the same position on head?  Did you perform a volume matched blind test?

Hard data and method - thats not so hard is it?


----------



## GrussGott (Jul 21, 2018)

Brooko said:


> So you admit to having no professional experience - yet you slate others and try to discredit



(1.) I possess the minimum credentials to back up my claim: I actually listened to the USB cables I'm commenting on.

(2.) I didn't TRY to discredit others, YOU fully and completely discredited them - You said Greg has ZERO scientific education, training, or experience.  FYI, that's pretty discrediting when it comes to making scientific claims.  Maybe you should apologize to Greg if that's not true.

(3.) I don't listen to gear, I listen to music, and I don't give a schiit why because music is a leisure hobby for me (although I did explain why a few posts back - look for the pictures).

What you're describing is a science hobby, so you should get busy and figure out why.  I don't care why.


----------



## Brooko

So your admittedly in the wrong section of the forums.  Thanks.  I'll let the mods know.


----------



## gregorio

GrussGott said:


> *[A] With USB cables, many who try high quality USB cables (and/or decrapifiers) experience better sound quality: What's going on?
> (1.)* *Signals processing engineers will tell you* this is because the better the conductor (and shielding) the lesser the chance of transmission data errors (which doesn't mean no chance, far from it, and the effect may be small or non-existent depending on config)
> *(2.)* *Others, including non-scientist/non-engineers* on this forum, claim conductor quality only must meet a minimum threshold to perfectly transmit an analog signal configured to represent digital data.
> [2a] Further they would claim any improvement is SQ must be mass hallucination.



A. You seem to have this completely backwards! You make various absolute explanations and statements of fact and THEN you ask "what's going on?". You should learn "what's going on" FIRST and only then presume to make statements of fact. If you don't do it this way around, you're going to be justly viewed as just another ignorant, deluded fan boy who has no idea "what's going on", is just spouting nonsense and/or repeating marketing BS.

1. You just made that up! Are YOU a digital signals processing engineer? How many of the world's digital signals processing engineers do you know? So firstly, how do you know what digital signals processing engineers "will tell you"? And secondly, even if you did know, as you clearly have little/no knowledge of the science/facts behind how digital works or the transmission of digital data, how would you know if you correctly understood it and it's context? You're just making up statements to support your fan boy beliefs. Why don't you find out the science/facts behind "what's going on" BEFORE you post your uninformed explainations, especially here in this forum?!

2. Again, that's just nonsense you've made up! Firstly, the cable is EITHER transmitting an analogue signal OR it's transmitting digital data. If it's the former then the cable is carrying an alternating current which is analogous to sound pressure waves (hence "analogue"), if it's the latter then it's a differential on/off switching signal representing zero and ones and is not an analogue signal, so make your mind up, which do you think it is; analogue OR digital? Secondly, it's not only "others, including non-scientist/non-engineers on this forum", Your statement is not only wrong, it's completely backward because it's EVERYONE except a relatively few deluded audiophiles! It's all those scientists/engineers who invented the USB protocols, it's all those engineers who designed all the world's digital devices and it's all those who use those billions of devices. If just one data bit out of every 500 million were corrupted during transfer then every digital device on the planet would crash every second or so and there would be no "digital age". *Are you claiming there is no "digital age" OR, that all digital devices must contain hundreds/thousands of dollars worth of "audiophile grade" data interconnects in order to work for longer than a few seconds at a time?*
2a. Please quote one person on this thread/forum who has claimed that "it must be mass hallucination". If you cannot provide such a quote then clearly you have just made-up a lie!

Hang on, only two? Where's the other potential explanations for "what's going on"? Are you completely ignorant of the other potential explanations or are you deliberately omitting them in order to troll or promote your fan boy delusions?



GrussGott said:


> (1.) I possess the minimum credentials to back up my claim: I actually listened to the USB cables I'm commenting on.
> (2.) You said Greg has ZERO scientific education, training, or experience.



1. As it's a physical impossibility to listen to a USB cable, then not only do you have zero credentials but you must also be deluded if you think you can listen to a USB cable.

2. Please quote where Brooko said I have "ZERO scientific education, training or experience". Can't provide such a quote? Then that's just another deliberate lie you've made-up! And, not just any lie but a laughably ironical one, because for 6 years I was a Senior University Lecturer and Course Leader (in Music/Digital Audio Technology), responsible for providing that "scientific education, training and experience" to others! However, you seem to be completely missing the point, this is the Sound Science forum, what's important here is the science and the facts, not what you think you heard, not your uniformed and erroneous beliefs/opinions and not even what my education, training or credentials are!

G


----------



## Phronesis

GrussGott said:


> That's because for anyone who's primary concern is listening to music, it's not only reasonable, but the only answer: try it, if you like the effect keep it.
> 
> Leisurely listening to music is all in what you perceive.
> 
> Sure, there are many here from the amateur science club who post-stoke each other for pleasure, but I prefer the music, and music lovers focus on it-does, not why-it-does.



A few things:

- Excessive focus on sound quality tends to interfere with enjoyment of music.  A lot of people on head-fi endlessly chase enjoyment by chasing gear upgrades, whereas they'd probably be better off getting some quality gear and then not thinking about the gear at all, and instead just enjoying the music.

- As I said before, gear can easily sound better to us because we expect it to, despite the gear not actually being better or significantly different.  This can result in wastage of a lot of money, including by people who don't really have the money to waste ("I'm leaning towards getting that expensive DAC/amp, but it will take me a while to save up for it").  This can also result in people making recommendations to others spend more on gear they can't really afford, despite the gear not actually sounding significantly better.

Here's a possible rule of thumb: if you *perceive* a piece of fancy gear to sound better, and the cost isn't an issue for you, go ahead and buy it, and don't do any careful testing which may provide evidence that it doesn't actually sound significantly better.  But do NOT share your perception with others, since you may influence them to waste money.

Here's an article which has some good discussion of how perception works, and how it's influenced by expectations.  The emphasis is on vision, but the main ideas apply to sound also:

http://jonlieffmd.com/blog/how-does-expectation-affect-perception

And here's a good paper on how expectations can influence perception of music:

https://www.nature.com/articles/s41598-018-24528-3


----------



## GrussGott (Jul 21, 2018)

gregorio said:


> how do you know what digital signals processing engineers "will tell you"?



Because I live and work in Silicon Valley and discuss digital signals processing with scientists and engineers who design and build DSP products (including audio) for military, industrial, and consumer applications.

I'd be thrilled to hear more about your experiences and less about your scientific conclusions since, as you've said, you're not a digital signals processing scientist.

Oh, and here's what Brooks said about you:

_Professional for decades_
_Musician and producer_
_Owns own professional studio_
_Grammy award winning_
He didn't list a single scientific credential.  So, yeah, he discredited any scientific conclusion you've made because as he points out - you're not a scientist.  If that's not accurate, blame him.



gregorio said:


> Firstly, the cable is EITHER transmitting an analogue signal OR it's transmitting digital data.



Let's be specific Greg:

A USB cable is transmitting an electrical signal of varying voltage - that signal is generated in such a way as to be more easily _*converted to digital*_ 1s and 0s in downstream equip.   (FYI: engineers typically refer to electrical signals as "analog signals", thus any electrical signal carried by a conductor can be referred to as "analog", even if the electrical signal is generated in such a way as to ease downstream conversion to digital data)

Since the USB signal on the wire is indeed electrical, it's vulnerable to electromagnetic interference either from the source or along the way, which can then cause the signal receiving equipment to either receive a value that wasn't sent, receive no value, or fail due to unexpected errors - this is because the receiving equipment uses a fixed methodology to interpret the electrical voltage variance of the signal.

As I've previously posted, here's what can happen when an electrical signal generated to represent (and be converted to) digital data is degraded:

The top line indicates the electrical signal when sent, received, and converted as intended, with the bottom line indicating the intention...







The red boxes above indicate the voltage measurement methodology the receiving equipment uses to translate the incoming analog electrical signal into digital data as theoretically represented on the second line.  If the two voltage measurements are read below or above the reference level, it's a "0", however if the two voltage measurements are one above and one below, it's a "1".

But, if there's excessive interference along the way, those transmitted electrical voltages can degrade causing translation errors due to inaccurate voltage measurement.  In this depiction on the top line you can see that the voltage representing the 4th bit was degraded and thus mistranslated by the receiving equipment (the voltage level didn't rise fast enough to be measured above reference and was thus interpreted as a "1" instead of as a "0" as intended):






These mis-translated bits ultimately wind up being converted by the DAC into sine waves, amplified by the amplifier and sent to headphones.

But just like any translation process, errors in originating transmission affect the quality of the translation, thus affect the quality of translated message (in this case the music you hear).

Thus the reason USB cables can have a "sound" is *NOT *because they transmit electrical sine waves that become degraded - _it's much worse than that!_

It's because USB cables carry a vulnerable electrical signal BEFORE conversion to end-use sine waves and any data lost or miscommunicated before conversion can _*AT BEST*_ have no impact on sound quality.  The magnitude of that impact depends on zillions of factors, but there's an impact of USB conductor and shield quality on end-result sound due to mid-stream translation.

All of that said, I do agree with @Phronesis : mostly likely cables are the last thing to focus on.  Transducers > amp > dac > cables

And lastly it's interesting to note that voltage measurements for "bit depth" are extremely tiny the higher the resolution and thus always vulnerable to EMI and/or other equip limitations that effect sound heard.  As you can see, at 16 bits we're talking 30 micro volts:






but I ain't no expert, so I make no conclusion other than what I've heard.


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## GrussGott (Jul 21, 2018)

Phronesis said:


> *Here's a possible rule of thumb*: if you *perceive* a piece of fancy gear to sound better, and the cost isn't an issue for you, go ahead and buy it, and don't do any careful testing which may provide evidence that it doesn't actually sound significantly better.  But do NOT share your perception with others, since you may influence them to waste money.



Here's a for-sure rule of thumb:

* Unless you're a digital signal processing scientist, don't present scientific conclusions about DSP gear.
* Unless you're a psychoacoustics scientist or audiologist don't present conclusions about how humans perceive sound.
* Feel free to share your gear experience on the gear experience sharing forum

*Good sciencey behavior for this (or any) forum:*
Hey, let's share research about DSP or audiological theory!
This might help us get closer to understanding experienced phenomena, but we can't present conclusions because we're just amateurs and - holy shiit - this is just a hobbyist audiophile forum.

*Bad non-sciencey behavior (i.e., most everyone here):*
USB cables don't matter and that's a fact!!  It's all delusions!  Because, you know, nothing is more scientific than making up explanations for things we can't explain about topics we're amateurs in!


----------



## Brooko

GrussGott said:


> Here's a for-sure rule of thumb:
> 
> * Unless you're a digital signal processing scientist, don't present scientific conclusions about DSP gear.
> * Unless you're a psychoacoustics scientist or audiologist don't present conclusions about how humans perceive sound.
> ...



For a start - the quote in the above post was not made by me.  So please stop making things up.  Second - despite evidence that Greg really does know his stuff (including digital audio) you still refuse to apologise.  Like I said - I've advised the Mods.  At this point I can only conclude you are trolling.  Congratulations - you are the first person to make my permanent ignore list.

I've always found the real measure of a man is to acknowledge when they are wrong - and apologise for it. I can't see that happening with you.  Good day - thats my last reply to you.


----------



## GrussGott (Jul 21, 2018)

Brooko said:


> For a start - the quote in the above post was not made by me.
> I've always found the real measure of a man is to acknowledge when they are wrong - and apologise for it.



You're correct, the above referenced post was not by you - not sure how/why that happened - I went in and corrected it.  See?  I can admit when I posted something that was wrong!


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## Phronesis

GrussGott said:


> Here's a for-sure rule of thumb:
> 
> * Unless you're a digital signal processing scientist, don't present scientific conclusions about DSP gear.
> * Unless you're a psychoacoustics scientist or audiologist don't present conclusions about how humans perceive sound.
> ...



We don't need to be specialists or professionals in a given area to become knowledgeable about that area.  But it does require prerequisite knowledge and then typically a lot of time and effort to read the literature in that area.

Regarding perception of sound, there's plenty of literature on that, and I provided a recent paper which goes into detail about how expectations can shape perception of music.

Regarding sharing gear experiences, those experiences are again based on perceptions, which are often unreliable.  A lot of perceptual experiences that get discussed on head-fi are misleading, such as upgrading to expensive cables making a transformative difference in the sound of already very expensive headphones which already come with fancy cables from the manufacturer.  I don't rule out the possibility that cables can make *some* difference in *some* situations, but am extremely doubtful that they make a substantial and worthwhile difference in the vast majority of situations.


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## GrussGott (Jul 21, 2018)

Phronesis said:


> *We don't need to be specialists or professionals* in a given area to become knowledgeable about that area.
> 
> Regarding sharing gear experiences, those experiences are again based on perceptions, which are often unreliable.


While one may attain a hobbyist / amateur's level of awareness of other's research (of digital signal science and audiology in this case), that amateur's awareness in no way qualifies them to offer conclusive, global advice based on "science" truisms.

This is why civil pilots, accountants, lawyers, doctors, stock brokers, et al, all have accreditation standards  - bad advice can feck up your life - thus it's both unethical and illegal for anyone not accredited to provide advice.

*I'm suggesting posters halt the unethical practice of doling out conclusive advice based on their amateur's-level awareness of digital signals and psychoacoustics science and/or research.
*
Again, disclaiming what you don't know and why you're not qualified is common courtesy.

There are literally hundreds of posters driven out of this sub-forum by the bullying tactics, so how about everyone knock it off - you're not scientists and you're not qualified.  Offer opinions, share research, but offer no conclusions because it's ethically irresponsible and metaphysically impossible for you to have any.

@amirm for example, may be controversial, but he shares his actual empirical data and experiences.  We can disagree, but he's open about what he's seen, why, and how.

@chef8489 for another example, I don't agree with him, but he shares his actual empirical data and experience.


----------



## Phronesis (Jul 21, 2018)

GrussGott said:


> While one may attain a hobbyist / amateur's level of awareness of other's research (of digital signal science and audiology in this case), that amateur's awareness in no way qualifies them to offer conclusive, global advice based on "science" truisms.
> 
> This is why civil pilots, accountants, lawyers, doctors, stock brokers, et al, all have accreditation standards  - bad advice can feck up your life - thus it's both unethical and illegal for anyone not accredited to provide advice.
> 
> ...



I'm a licensed professional engineer.  I understand professional ethics and the obligation to not offer professional advice outside one's areas of expertise.

But you're conflating understanding and discussing science (and technology) with offering professional advice.  We can do the former without doing the latter.  I can and do know a lot about biomedicine without needing to be a doctor.  The science in a given area can be understood without going to the level of becoming a specialist in that area.  Physics of drivers, acoustics, circuit theory, psychoacoustics, etc. can be learned in depth by people who have prerequisite technical background and the motivation to learn it.  Nowadays, knowledge is accessible online to all of us.

Seems that you're trying to argue that, in discussions among non-specialists, all opinions are equally (in)valid and (un)informed.  That's obviously not the case.


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## Steve999

@GrussGott, you and I are not on the same side on the merits, but I am with you on this one, full stop.



GrussGott said:


> There are literally hundreds of posters driven out of this sub-forum by the bullying tactics, so how about everyone knock it off.


----------



## Phronesis

Steve999 said:


> @GrussGott, you and I are not on the same side on the merits, but I am with you on this one, full stop.



+1

The Sound Science forum can't be described as neutral and objective, and there's no shortage of 'bullying' behavior here.  I hope my comments didn't come across that way.


----------



## bigshot (Jul 21, 2018)

donunus said:


> Last time I checked this hobby was about getting enjoyment out of one's system and if something sounds better to you then it is evidence enough



If you are getting enjoyment because of that bottle of wine you're drinking, it doesn't make sense to recommend a particular interconnect as being the source of the better sound. Solipsist impressions are fine for you. They mean jack diddly to me. The only things we can share are objective facts... or perhaps a glass of that wine you're drinking.



donunus said:


> I'm out lol



BUH BYE!



donunus said:


> Oh I have done a blind test but its really hard to prove to you unless you were here so this thread is actually useless lol



WOW! Back so soon! Welcome back. If you do a blind test, you can share how you conducted it. Other people can replicate your results. That's how science works! Blind tests aren't hard to do. You just have to have a switch box, a way to balance the line level, and a friend to help flip the switch for you. The switch box and level adjustment is easy. You have a friend, don't you?


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## bigshot (Jul 21, 2018)

GrussGott said:


> Why would I do that? According to your list, Greg is not
> * A digital signals processing scientist
> * A digital signals engineer
> * A digital audio products designer
> ...



Be careful of criticizing other people's credentials. Someone may demand the same of you. Personally, I don't care about resumes. I can tell from what people say whether they know what they're talking about. Fair warning... You are being judged by your words and the degree of respect you receive will vary accordingly. When it comes to bullying behavior, ye shall reap just what you sow. I get along fine with people who are polite and respectful and listen to what other people say. But I don't suffer fools gladly.


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## GrussGott

Phronesis said:


> I
> But *you're conflating understanding and discussing science (and technology) with offering professional advice*.  We can do the former without doing the latter.



No, in fact I said the exact opposite of that.

What we *CAN *say is:
* In my experience with X cable in X system ...
* I conducted a study with this methodology and it found that ...
* I read X research linked here that concluded that ...

What we _*CAN'T *_say is:
* It's impossible for an expensive USB cable to affect audio because science because
(a.) everyone here is an amateur, and
(b.) every human is an amateur compared to nature.

 If you're an experienced engineer working in any industrial setting, then every single week of your career at least one thing happened that nobody can explain ... which is the wise never rule anything out.


----------



## Redcarmoose

I see the USB cable argument going the same route as using balanced connections. At first only balanced connections were important for long long cables. There was no proof about balanced headphone cables adding any improvements. If there was proof stated it was argued about. Then slowly in the night balanced headphone amplifiers and balanced headphone cables started to become widely introduced in the community to the point SS does not concern themselves with the subject.

Just like fancy USB cables, they cost more and are a fairly new thing with  questionable ways of measuring audio improvements.

In 10 years audiophile USB cables will be more common.


----------



## GrussGott (Jul 21, 2018)

bigshot said:


> Be careful of criticizing other people's credentials. [/SIZE]



FYI I didn't criticize anybody's credentials, I factually stated what those credentials are NOT.  and neither you nor greg are digital signal scientists or engineers so neither of you are in any way qualified to offer anything other than experiential opinions to anybody.  That doesn't mean you might not have some great experiences to share, or some excellent studies you've read, it just means you're hobbyists only.

So the point is, in any posts where you state scientific conclusions, be ethical and add that you're amateurs only, thus any "science" conclusions you've drawn are of the lowest possible scientific standard, which is to say the guesswork of an amateur.


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## GrussGott (Jul 21, 2018)

Redcarmoose said:


> I see the USB cable argument going the same route as using balanced connections.
> Just like fancy USB cables, they cost more and are a fairly new thing with  questionable ways of measuring audio improvements.
> In 10 years audiophile USB cables will be more common.



Love this - much the same as with supplements in fitness and body building; most don't offer much if any benefit (and many are harmful) but some originally derided as killers, aren't and are effective for many, and others have become medically recommended staples (like whey protein).

The problem with USB cable research is, at the end of the day, your ears, your system, your music.

People know what they hear.  The idea that's a delusion is it's own reverse delusion!  "Prove to me with data/reports/studies I can hear something - once I intellectually believe,  then I'll hear it"

We all know instantly the difference between live music and a speaker, no matter the quality of the speaker, in virtually any location or setting.  Most can easily even instantly point out live music played through speakers, like electric guitar, versus a CD of the exact track.

This arrogant notion that all of sound reproduction science is understood and measurable would be laughable if there weren't so many people here that think seeing data allows them to hear things.


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## Redcarmoose

https://www.head-fi.org/threads/balanced-cable-what-is-it-and-why-would-i-want-it.753012/


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## castleofargh

GrussGott said:


> While one may attain a hobbyist / amateur's level of awareness of other's research (of digital signal science and audiology in this case), that amateur's awareness in no way qualifies them to offer conclusive, global advice based on "science" truisms.
> 
> This is why civil pilots, accountants, lawyers, doctors, stock brokers, et al, all have accreditation standards  - bad advice can feck up your life - thus it's both unethical and illegal for anyone not accredited to provide advice.
> 
> ...


on one hand you've made all those posts based on half understood electrical principles, and your self powered belief that anything you feel sighted comes from sound. on the other hand you troll others for talking theory without being lead scientists in the domain they're trying to discuss... such double standards make it hard to take anything you say seriously.



about the forum and bullying, the assumption in this section is that we should work on evidence based models. TBH I wish I could apply a rule like on Hydrogen and simply forbid and delete objective claims made from sighted impressions. that would solve so many issues and clarify so many kitty fights.
this section is the only allowed place to discuss placebo and blind testing on the forum, those who disregard both, like you clearly do, should logically post somewhere else. if I go and keep bringing up blind tests in a headphone impression topic, I'll soon be bullied just the same by people telling me to shut up and crawl back to my section. and a few times when I insisted to counter false claims, I got locked out of the topic by moderation. so let's not pretend that this is something unique to this section. when one decides that "I know what I heard" provides objective facts about a cable. first, it really doesn't. second, wrong section!
 you're lucky that Brooko isn't a modo anymore or you'd probably have experienced first hand what being "driven out of this sub-forum" feels like  . right now I'm inclined to show a little more tolerance because I remember how this topic got beamed up in Sound Science by Mr Sulu without warning. you didn't ask to be here and I can appreciate that. but it's been some time now, we're here, and when in Rome...

 if someone believes in his idea, he should do what he can to provide evidence so that people who do care about facts can take the evidence into account when forming their own opinions. fighting it out with rhetoric and putting worlds in other people's mouth is certainly not the answer.


----------



## Phronesis

GrussGott said:


> People know what they hear.  The idea that's a delusion is it's own reverse delusion!  "Prove to me with data/reports/studies I can hear something - once I intellectually believe,  then I'll hear it"
> 
> We all know instantly the difference between live music and a speaker, no matter the quality of the speaker, in virtually any location or setting.  Most can easily even instantly point out live music played through speakers, like electric guitar, versus a CD of the exact track.



It would be more accurate to say that people tend to believe what they perceive, because they're not aware of the subconscious cognitive processes involved in creating those perceptions and they (we) have the sense that those perceptions 'mirror' reality.  There's ample literature going back decades which discusses how past experience, expectations, etc. shape perception.  I suggest doing some reading about visual illusions, and try some of them yourself.

This doesn't mean that we can never tell a difference between two sounds that are actually physically different.  But it does mean that we can perceive differences in sounds that are physically the same.


----------



## GrussGott (Jul 21, 2018)

castleofargh said:


> *if someone believes in his idea, he should do what he can to provide evidence so that people who do care about facts can take the evidence into account when forming their own opinions*.



Thanks for supporting me! I couldn't agree more except to add that "he" should also disclaim when giving advice whether they're doing so as a trained, experienced digital signals scientist or purely as a hobbyist.  As you point out, I've provided all of the evidence to back up every claim I've made: I heard it, and told you my understanding of why it happens.  I even included pictures!  *If you believe that to be only half understood,* *please provide the other half!  *Feel free to reply to my post with the pictures and fill in the blanks ...

Maybe the completed result could even be a product of this sub-forum we share to help others?

*As to "when in Rome",* isn't this the Sound Science *public *forum?   *Because what you described sounds like a private forum* where those invited are screened for beliefs and behaviors.

Sounds you'd be more comfortable in a private forum where all share like beliefs and opinions?   Maybe I didn't understand what you meant ...


----------



## GrussGott (Jul 21, 2018)

Phronesis said:


> It would be more accurate to say that people tend to believe what they perceive, because they're not aware of the subconscious cognitive processes involved in creating those perceptions and they (we) have the sense that those perceptions 'mirror' reality.  *as far as I've read  and in my amateur's opinion*



FTFY - science!  modesty, disclosure and ethics always appreciated in science.



Phronesis said:


> This doesn't mean that we can never tell a difference between two sounds that are actually physically different. But it does mean that we can perceive differences in sounds that are physically the same.



maybe, but that would presume we can fully, accurately, and completely "physically" measure sound, and that we're perfect interpreters of those measurements and that we further perfectly understand how the human ear works and we perfectly understand how the human brain interprets those ear functions.

That kind of accuracy and understanding doesn't sound plausible to me - does it to you?


----------



## Phronesis

GrussGott said:


> maybe, but that would presume we can fully, accurately, and completely "physically" measure sound, and that we're perfect interpreters of those measurements and that we further perfectly understand how the human ear works and we perfectly understand how the human brain interprets those ear functions.
> 
> That kind of accuracy and understanding doesn't sound plausible to me - does it to you?



As I've myself argued in this forum, I don't think we can assume that a given set of measurements will necessarily capture all differences in signals or equipment which could be perceived by listeners. 

But at the same time, we need to consider all of the factors which could contribute to our perceiving differences between things.  The research (by specialists, not amateurs) shows clearly that one of the biggest factors in that variation is our cognitive processing involved in perception.  Again, that cognitive processing can be highly influenced by factors such as expectations, without our even being aware of that influence.

Take a look at how powerful these visuals illusions are: http://brainden.com/visual-illusions.htm.  Even when you *know* your perception is fooling you, it's difficult to override your perception and not be fooled by it.  A main reason why these perceptions fool us and work as illusions is because of our expectations of how things are in the world.


----------



## Brooko

castleofargh said:


> you're lucky that Brooko isn't a mod anymore or you'd probably have experienced first hand what being "driven out of this sub-forum" feels like  . right now I'm inclined to show a little more tolerance because I remember how this topic got beamed up in Sound Science by Mr Sulu without warning. you didn't ask to be here and I can appreciate that. but it's been some time now, we're here, and when in Rome...



All I'm asking for is common decency and for people not to hide behind a wall of ignorance and write their own rules.

You have one poster writing about subjective findings, but then declaring all science based finding as null and void (based on qualifications).  When questioned/refuted by someone with knowledge, he gets to dismiss out of hand.  He can post what he wants, and then can dismiss everyone else's. When they provide information he can say that they are ordinary laymen (something he himself admits), plus he can then attack them.

Some of Greg's credentials have already been provided, showing he is a professional in his field, he has years of experience in a production environment (so has practical knowledge of the differences of cables) - and at least as much subjective experience as our "learned friend".  Whats more - Greg has backed up with the fact that he for "*6 years I was a Senior University Lecturer* and Course Leader (in Music/*Digital Audio* Technology), responsible for providing that "scientific education, training and experience" to others!"

In most peoples eyes, this qualifies Greg as the expert with far more knowledge than most of us in this field.  I still have not seen any apology from said gentleman - and he still continues to troll the thread without accepting the expert opinion of the person who actually knows.

Yes  - you are right CoA - if I was still Moderating, said member would have been given a warning by now.  And its not about trying to silence a POV which does not align with my own.  Its about having a *facts based discussion* in the *Sound Science* section.  There was a time once when that was encouraged ....... sadly I see the standards somewhat slipping.


----------



## Brooko

Phronesis said:


> As I've myself argued in this forum, I don't think we can assume that a given set of measurements will necessarily capture all differences in signals or equipment which could be perceived by listeners.
> 
> But at the same time, we need to consider all of the factors which could contribute to our perceiving differences between things.  The research (by specialists, not amateurs) shows clearly that one of the biggest factors in that variation is our cognitive processing involved in perception.  Again, that cognitive processing can be highly influenced by factors such as expectations, without our even being aware of that influence.
> 
> Take a look at how powerful these visuals illusions are: http://brainden.com/visual-illusions.htm.  Even when you *know* your perception is fooling you, it's difficult to override your perception and not be fooled by it.  A main reason why these perceptions fool us and work as illusions is because of our expectations of how things are in the world.



Thanks you.  And to add to that - the line in my signature is very apt:
“*Sometimes, the truths are those things you want to hear, and sometimes what we call truths are habitual lies we're comfortable with*.”


----------



## bigshot (Jul 21, 2018)

GrussGott said:


> FYI I didn't criticize anybody's credentials, I factually stated what those credentials are NOT.



Are you a "digital signal scientist"? I don't think you have any qualifications whatsoever other than being a customer of snake oil. In case you haven't been paying attention, Gregorio is a recording engineer and has even taught the subject. He is perfectly qualified to offer an opinion, and you could learn something from him if you actually listened instead of marching around like a poser. Get a clue.

This joker shows up every six months to a year, chimps out for a week or so and then disappears again. He's a troll. There's nothing to discuss with him because he isn't interested in the subject of this forum, he's only interested in stirring up crap. I am now going to start talking past him to all of the rest of you. I'm not going to quote him any more.


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## Arpiben

Why not start understanding digital transmission with this:


----------



## bigshot

My dad was a ham radio operator back in the days where you had to do morse at a certain speed to get a license. He had records that he would practice with. I remember sitting in my room zoning out to the sound of "dah dit dah dit daaah daaah dit dah" through the wall. His call letters were ZCF which were the three hardest letters to tap out.


----------



## GrussGott (Jul 21, 2018)

Brooko said:


> You have one poster writing about subjective findings, but then declaring all science based finding as null and void (based on qualifications).  When questioned/refuted by someone with knowledge, he gets to dismiss out of hand.  He can post what he wants, and then can dismiss everyone else's.



@Brooko I never, ever said "science based findings" were null and void - I said posters shouldn't provide advice based on scientific conclusions when they have no scientific credentials/experience to make those scientific conclusions (e.g., "USB cannot affect sound quality because science!").  Those two similar things are quite different.

You, yourself, just posted about credentials "in most people's eyes" - well not in my eyes, so you absolutely ARE advocating silencing someone because they disagree with you.  That's playing arbitrary popularity contests, rather than moderating.  FURTHER, @bigshot called me foolish and delusional like 20 times.  So open name-calling isn't apology-worthy to you?  Seems like arbitrary bias.  _(note: I don't care about name-calling)_

*To be ultra clear about what credible credentials are "in my eyes" for stating scientific conclusions of USB cable capabilities:*
* 20 years of experience in digital signals science/engineering and/or technical product development ... then maybe.  Call me a cynic.

*Now, back to USB cables - do any of you have any peer-reviewed scientific papers showing the physical impossibility of USB cable architecture (beyond base spec) affecting sound quality?
*
Because if you did, that would useful and those papers are probably by digital signals scientists which I understand is a much higher level of qualification than some of you require.


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## GrussGott (Jul 21, 2018)

bigshot said:


> Are you a "digital signal scientist"?



No, which is why I don't offer scientific conclusions about digital signals products and recording engineers and railroad engineers shouldn't either.


Anyway, let's see that peer-reviewed study about how in-spec USB cables in digital audio systems cannot affect a transmitted signal, then we can just close up this thread.


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## bigshot




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## gregorio

GrussGott said:


> [1] He didn't list a single scientific credential. So, yeah, he discredited any scientific conclusion you've made because as he points out - you're not a scientist. If that's not accurate, blame him.
> [2] FYI: engineers typically refer to electrical signals as "analog signals", [2a] thus any electrical signal carried by a conductor can be referred to as "analog", even if the electrical signal is generated in such a way as to ease downstream conversion to digital data)



1. Brooko did not list my entire resume, he just responded to an erroneous assertion that I'm an amateur. Clearly he did NOT discredit any scientific conclusion I made, that's just another lie that you've made up!

2. What do you mean "for my information"? You're funny! You're NOT an audio engineer, never been an audio engineer but you presume to give a "FYI" about what's typical for engineers to an actual engineer with 27 years professional experience. If that's not evidence of delusion, I can't imagine what is!!
[2a] To address the actual point: In the audio world, an analogue signal is one that is analogous to an acoustic sound signal, hence why it's called "analogue" in the first place! It's really an extremely simple concept to grasp. 



GrussGott said:


> I'm suggesting _posters halt the unethical practice of doling out conclusive advice based on their amateur's-level awareness of digital signals and psychoacoustics science and/or research._



Firstly, why don't you take your own suggestion? Secondly, who are you referring to? Obviously not me, as I have a professional's-level awareness of digital signals. And additionally, there are quite a few people in this forum who may not be professional scientists or engineers but have a good understanding of digital signals. Vlearly you don't fall into either category.

So what are you saying, that doling out conclusive advice based on amateur's-level awareness of digital signals is not acceptable but doling out conclusive advice based on ignorance and fan boy delusion is?



GrussGott said:


> [1] Thanks for supporting me!
> [2] As you point out, I've provided all of the evidence to back up every claim I've made: I heard it, and told you my understanding of why it happens.



1. He wasn't, he was doing the exact opposite! Another simple concept you've failed to grasp ... Oh dear, this seems to be a pattern!
2. You've provided no evidence whatsoever beyond anecdotal evidence. You berate others for not being professional scientists but you don't even seem to know what science is or what qualifies as scientific evidence. Hypocrite, delusional or both?



GrussGott said:


> [1] No, which is why I don't offer scientific conclusions about digital signals products and recording engineers and railroad engineers shouldn't either.
> [2] ... maybe, but that would presume we can fully, accurately, and completely "physically" measure sound ...
> [2a] That kind of accuracy and understanding doesn't sound plausible to me - does it to you?



1. You're joking right? You're saying that engineers who are specifically educated and trained to record, manipulate and reproduce digital signals are not qualified to offer scientific conclusions about digital signals or even the basics of what digital signals are or how they work? What do you think digital audio engineers are educated in, how trains work? Your statement is so bizarre, it's funny!

2. If we can't measure sound, how can we record, digitise or reproduce it?
2a. Huh? It doesn't sound plausible to you that hundreds of millions of bits of data can be transferred per second without error? How do you think smartphones, tablets, laptops, digital TV's, etc., work without crashing every second or so? Or, are you saying that you don't understand the proven basics of how digital audio and digital information in general works? ... This is NOT the "What sounds plausible to GrussGott" forum, it's the sound science forum and the actual facts/science do not depend on what you find plausible!  What "doesn't sound plausible" to me is that someone could be so incapable of grasping such simple concepts ... either trolling or delusion sounds far more plausible to me!!

G


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## gregorio

GrussGott said:


> Anyway, let's see that peer-reviewed study about how in-spec USB cables in digital audio systems cannot affect a transmitted signal, then we can just close up this thread.



Again, you're joking right? Are you really saying that USB spec cables cannot accurately transmit USB specification signals? If so, what is the point of USB specification cables in the first place and how can the USB protocol ever work? Do I have to provide you with a peer reviewed study indicating that the USB protocol works bit perfectly (with USB spec cables), isn't billions of practical demonstrations of countless terabytes of data over more than two decades not enough?

Honestly, how ridiculous are you going to get?

G


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## bigshot

Prove a negative, Gregorio!


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## Steve999 (Jul 21, 2018)

You are questioning first principles and premises. I like that. I'm a big fan of that. It gets you places if done well. Yes, it makes people uncomfortable and they want you to go away. So let me look at some of your premises. I understand by one account that you come around here every six months or so and annoy everybody. Good! And argument, if constructive, can constitute one of the great pillars of higher-level learning. Don't get me wrong though--practical experience and book-learning are just as crucial.


So, respectfully, as to your premises: First, never underestimate the power of a brilliant uneducated mind. Questioning credentials is a relatively lowly method of reasoning when it comes to constructive argument. I dispute the premise that a person who is not educated in a particular field should not speak in that field as an authority. See:

https://en.wikipedia.org/wiki/Michael_Faraday

https://en.wikipedia.org/wiki/Wright_brothers


I am not going to pay $33 for it and it would be improper for me reproduce it here in violation of copyright law but this might possibly do the trick as to proving in a peer-reviewed paper the audio transparency and flawless data transmission of USB cables, from the year 2000:

http://www.aes.org/e-lib/browse.cfm?elib=9053

So by your reasoning this may mean that we can close the thread.


Also, I question your premise that engineers are not competent to speak on scientific topics in their field. Let's take the example of a student who gets a graduate degree in chemical and biomolecular engineering. They are going to have to be at least competent in the sciences of biology, chemistry, computers, physics, and statistics, at a minimum. Engineers apply science. If they are not competent to do so then they will fail miserably at their craft. They may have a better working knowledge and more fertile and active minds and intuition than the scientists themselves in those same fields. They may also be capable of making major advances in the fields of science in which they practice. _See _Nikola Tesla, and Wilbur and Orville Wright, for two examples who have profoundly affected all of our lives.

By the way I am one of the several credentialed professionals I believe you mentioned in this thread (I apologize if it was not you). But I am extremely conscious in day-to-day life not to assume that this means I am right and someone else is wrong, though it is all too human to do so. Argument by authority is pretty lame in my book. Much snake oil is pedaled on that basis. It cuts both ways--it shouldn't be common practice in Sound Science or in the other parts of head-fi. In day to day life we have to rely on academic and scientific authorities and principles for innumerable things, down to driving our cars or running our air conditioners. But if there is a dispute, it's a pretty weak way of making your point--argument by authority is a perilous and potentially deceptive form of argument, and nobody learns much or gets anywhere new. Everyone just talks in circles. I am not very respectful of either questioning qualifications or flouting them in an argument. Either is too prone to amount to nothing more than a rather unpleasant and unwarranted ad hominem attack.

If you disagree with me, write, and write well. I may not answer, but I will read with genuine interest and kind feelings. I am not a big fan of posting here for just some of the reasons that you mention.



GrussGott said:


> No, which is why I don't offer scientific conclusions about digital signals products and recording engineers and railroad engineers shouldn't either.
> 
> Anyway, let's see that peer-reviewed study about how in-spec USB cables in digital audio systems cannot affect a transmitted signal, then we can just close up this thread.


----------



## Phronesis

Steve999 said:


> So, respectfully, as to your premises: First, never underestimate the power of a brilliant uneducated mind. Questioning credentials is a relatively lowly method of reasoning when it comes to constructive argument. I dispute the premise that a person who is not educated in a particular field should not speak in that field as an authority. See:
> 
> https://en.wikipedia.org/wiki/Michael_Faraday
> 
> https://en.wikipedia.org/wiki/Wright_brothers



… or Elon Musk.  He's a guy that I'm guessing will still be talked about a century from now.


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## Glmoneydawg (Jul 21, 2018)

Phronesis said:


> … or Elon Musk.  He's a guy that I'm guessing will still be talked about a century from now.


Elon touts lithium ion batteries. ...ni cad batteries last anywhere from 6 to 10 years.....part of my business is warranty work on batteries. .....we put an incredible number of lithium ion batteries in the landfill every week ....3 years is average life expectancy on this crap.This goes against his whole philosophy  doesn't it?...so yep he will be talked about .


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## GrussGott (Jul 22, 2018)

Steve999 said:


> You are questioning first principles and premises. I like that. I'm a big fan of that. It gets you places if done well. Yes, it makes people uncomfortable and they want you to go away. So let me look at some of your premises. I understand by one account that you come around here every six months or so and annoy everybody. Good! And argument, if constructive, can constitute one of the great pillars of higher-level learning. Don't get me wrong though--practical experience and book-learning are just as crucial.
> 
> So, respectfully, as to your premises: First, never underestimate the power of a brilliant uneducated mind. *Questioning credentials* ...



This is all pretty good stuff with one key error: I'm not questioning anyone's credentials (everyone can make their own conclusions about that - I have), only the ethics of stating science-based conclusions without significant and practical experience in the actual research and design of the item in question: USB cables for hi-fi digital audio transmission.  (which nobody here has claimed to have) or by busting out peer-reviewing research demonstrating their conclusion. (which nobody here has produced)

And yes - the *OP's question could be easily and conclusively answered with peer-reviewed research showing the physical impossibility of an in-spec USB cable affecting downstream sound quality*. Anybody making that claim should just show us the paper and then, yes, we can close this thread.  QED.

The paper you posted doesn't seem to address the OP's question: why do USB cables improve audio quality?  Just that using USB for "excellent" audio is possible: _"This document demonstrates that USB technology is now mature to have a full range of applications with excellent Audio quality."_

Again, everyone - engineers or otherwise -- can comment and form any opinions they want.  go for it!  Let's discuss!  It's when they present their opinions as scientific fact to those asking for advice that it becomes irresponsible at best.

It's not ethical to portray advice as settled science when the science isn't settled - and if it is, it's as easy as linking to the peer-reviewed paper.  /thread.


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## Arpiben

GrussGott said:


> This is all pretty good stuff with one key error: I'm not questioning anyone's credentials (everyone can make their own conclusions about that - I have), only the ethics of stating science-based conclusions without significant and practical experience in the actual research and design of the item in question: USB cables for hi-fi digital audio transmission.  (which nobody here has claimed to have) or by busting out peer-reviewing research demonstrating their conclusion. (which nobody here has produced)
> 
> And yes - the *OP's question could be easily and conclusively answered with peer-reviewed research showing the physical impossibility of an in-spec USB cable affecting downstream sound quality*. Anybody making that claim should just show us the paper and then, yes, we can close this thread.  QED.
> 
> ...



Why do you need an answer since,IMHO, your posts are a perfect example of digital transmission issues:

Your arguments are burried in a lot of noise. Your Signal to Noise Ratio is negative in Decibel and far out of specifications for an information Transmitter.
Nevertheless your posts are reaching us unaltered through different media/technologies/cables.
As Receivers, some of us, are not able to properly retrieve the information you are sending.Too much noisy.
As Receivers, others are pleased with that noise and do bellieve that Receivers in point 3 are the ones out of specifications.
Addendum:

Using Ferrites/ Dongles/decrapifiers/etc at Receivers point 3 side will not help understanding you better
Using corrective action at Transmitter side (different argumentation) will allow Receivers in point 3 to deal with your information but Receivers in point 4 will be out.


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## donunus (Jul 22, 2018)

bigshot said:


> If you are getting enjoyment because of that bottle of wine you're drinking, it doesn't make sense to recommend a particular interconnect as being the source of the better sound. Solipsist impressions are fine for you. They mean jack diddly to me. The only things we can share are objective facts... or perhaps a glass of that wine you're drinking.
> 
> 
> 
> ...



Priceless lol Scientific proof this thread is useless. If you are actually serious, how do you hocus pocus people using my ears. Surely, trained ears with some experience will pass and the newbies will fail due to the lack of training in finding the subtleties here. It is defininitely not as easy as comparing the sound coming from a boom car to a refined electrostat but the differences were there and I identified the cable playing after being used to how each cable sounded for a few days. All cables were covered in black cloth and labeled a number during the test then I took notes every listen. Someone else swapped the cables by the way so I didn't try to cheat and touch them to feel which one was under the cloth.


----------



## Phronesis

GrussGott said:


> This is all pretty good stuff with one key error: I'm not questioning anyone's credentials (everyone can make their own conclusions about that - I have), only the ethics of stating science-based conclusions without significant and practical experience in the actual research and design of the item in question: USB cables for hi-fi digital audio transmission.  (which nobody here has claimed to have) or by busting out peer-reviewing research demonstrating their conclusion. (which nobody here has produced)
> 
> And yes - the *OP's question could be easily and conclusively answered with peer-reviewed research showing the physical impossibility of an in-spec USB cable affecting downstream sound quality*. Anybody making that claim should just show us the paper and then, yes, we can close this thread.  QED.
> 
> ...



Perhaps it’s not a fact that it’s been conclusively shown that there could be no perceivable difference in sound when using two different USB cables.  However, it is indeed a fact, based on decades of research, that perception is unreliable to the extent that large differences may be perceived to exist which do not actually exist.  Controls can be introduced to make perception more reliable, but you haven’t used such controls, so it would be unwise for you to conclude that you’ve perceived a real difference in sound.  Try introducing those controls and see what your results are.  I did that when comparing DAC/amps, and was shocked to find that differences I had clearly perceived previously disappeared when introducing those controls.


----------



## Phronesis

donunus said:


> Priceless lol Scientific proof this thread is useless. If you are actually serious, how do you hocus pocus people using my ears. Surely, trained ears with some experience will pass and the newbies will fail due to the lack of training in finding the subtleties here. It is defininitely not as easy as comparing the sound coming from a boom car to a refined electrostat but the differences were there and I identified the cable playing after being used to how each cable sounded for a few days. All cables were covered in black cloth and labeled a number during the test then I took notes every listen. Someone else swapped the cables by the way so I didn't try to cheat and touch them to feel which one was under the cloth.



I jumped into this thread late and haven’t seen your posts where you describe your methodology and results.  Could you provide links to those posts?


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## donunus

I haven't posted much. I just started posting again the past few days (3 days or so). The tests I did with USB cables were done a few years ago and I just posted here baffled at why people don't actually try something like the simple blind test I did to see if they could hear a difference or not. Now if a person hears the differences with consistent notes on which cable is which, how much is that sound worth to you and is the preferred cable worth the small difference in sound? Or is it an important enough change to warrant whatever cost of the cable in question.

So far as the engineering explanation is concerned, there are things everywhere on the internet explaining why USB cables sound different but it is not really useful information if a certain person can't hear the differences anyway. So I suggest everyone just listen and throw biases away then make their own decision if the differences are significant enough to bother obsessing about


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## Phronesis

donunus said:


> I haven't posted much. I just started posting again the past few days (3 days or so). The tests I did with USB cables were done a few years ago and I just posted here baffled at why people don't actually try something like the simple blind test I did to see if they could hear a difference or not. Now if a person hears the differences with consistent notes on which cable is which, how much is that sound worth to you and is the preferred cable worth the small difference in sound? Or is it an important enough change to warrant whatever cost of the cable in question.
> 
> So far as the engineering explanation is concerned, there are things everywhere on the internet explaining why USB cables sound different but it is not really useful information if a certain person can't hear the differences anyway. So I suggest everyone just listen and throw biases away then make their own decision if the differences are significant enough to bother obsessing about



If you do a blind test and consistently hear a difference, it’s certainly reasonable for you to count that as meaningful evidence and base your decisions on it. Of course, if you want others to give weight to your results, you would need to lay out the details of what you did, similar to what’s expected when submitting a paper for peer review.


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## donunus (Jul 22, 2018)

All I did was have a friend swap the cables covered in black cloth labeled numbers 1-4. I took notes of the sound of each number and guessed which cable it was based on listening to all of them previously. Music played were ones I was familiar with and I chose the music to play while he swapped cables every minute or so and played the same track for each cable. He played 5 tracks for me in total. I Identified which cable was which. I think my conclusion was that for my sub 1000 dollar headphone setup, a 20 dollar belkin gold was fine but was definitely a worthy improvement over a cheap freebie to my ears. I had an expensive cable included that sounded different as well but felt that it actually didn't do much more for me in terms of musical enjoyment. Another one was an audioquest cable which was also decent FWIR but I can't remember all the details of my notes anymore. This was a few years back. I bought the belkin gold, a 20 dollar no brainer and never thought much more about it.


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## gregorio

GrussGott said:


> [1] This is all pretty good stuff with one key error: I'm not questioning anyone's credentials ...
> [1a] ... only the ethics of stating science-based conclusions without significant and practical experience in the actual research and design of the item in question: USB cables for hi-fi digital audio transmission. (which nobody here has claimed to have) or by busting out peer-reviewing research demonstrating their conclusion. (which nobody here has produced)
> [2] And yes - the *OP's question could be easily and conclusively answered with peer-reviewed research showing the physical impossibility of an in-spec USB cable affecting downstream sound quality*. Anybody making that claim should just show us the paper and then, yes, we can close this thread. QED.
> [3] It's when they present their opinions as scientific fact to those asking for advice that it becomes irresponsible at best.
> [4] It's not ethical to portray advice as settled science when the science isn't settled ...



1. Clearly that's a lie. Anyone can read your posts over the last few pages and easily see for themselves that you've consistently questioned people's credentials, so what's the point of posting such an obviously refutable lie?
1a. Do I need to be a geology research scientist in order to state the "science based conclusion" that the Earth is not flat? Can a school teacher or university lecturer not state such a conclusion? What about an inter-continental airline pilot who is educated and trained to navigate and fly around the Earth, do they have to be a research geologist to state that the Earth isn't flat?

2. What do you mean "And yes"? The peer-reviewed research you're asking for CANNOT exist because science cannot prove a negative, which you would know if you had any understanding of science! Secondly, besides trolling, what's the point of arguing against a claim that NO ONE here has or is making? The claim being made is that bit perfect transfer of data through standard USB spec cables is not only possible but is physically demonstrated by countless tens of millions of people every day for more than 20 years! Your claim is that standard USB spec cables are error prone and that expensive audiophile cables reduce that error. Where is your evidence that standard spec USB cables are so error prone? How could you even logically provide reliable evidence for a claim which contradicts such a massively well demonstrated fact? And, where is your reliable evidence that audiophile USB cables actually do reduce error compared to standard USB spec cables or are you saying that audiophile cables result in better than bit perfect transfer?

3. It is scientific fact that standard USB spec cables transfer data bit perfectly, you don't need to be a research scientist to copy a file across a USB spec cable and run some free software to check if the copy and the original are bit for bit identical. This is a trivially easy to prove objective fact, NOT an opinion! You on the other hand are presenting a personal opinion that is contrary to the proven objective facts, without even a single shred of reliable evidence. This is not "irresponsible at best", it's an insulting attempted perversion of this forum and if that's not bad enough you then further insult those who recount the proven objective facts. AGAIN, this is not your personal opinion forum or a forum dedicated to what you are capable of believing is "plausible"! 

4. Not settled? There can't be many more well demonstrated objective facts in the whole of human history!

Is the Earth flat? Am I not allowed to state it's a scientific fact that the Earth is not flat? Do you think it would be acceptable to post in a science/factual forum that the Earth is flat and then insult those who refute your claim as amateurs with no idea or right to state the actual facts? The ONLY difference between this ridiculous Flat Earth example and your contribution to this thread is PURELY what you personally find "plausible"!!! Or maybe you're just trolling, which is it?

G


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## GrussGott (Jul 22, 2018)

gregorio said:


> It is scientific fact that standard USB spec cables transfer data bit perfectly,* you don't need to be a research scientist to copy a file across a USB spec cable* and run some free software to check if the copy and the original are bit for bit identical.



*sounds like you're technically equating USB file transfer with USB audio transfer?  Did I read that right??*

So you're disagreeing with this author's explanation of USB file transfer versus USB audio transfer?  Where's he getting it wrong?  You're saying they're the same?

*Asynchronous & Isochronous Basics*
Isochronous refers to the _transfer type_ and asynchronous USB essentially refers to the location of the master clock (who controls the clock?). In the context of USB, isochronous and asynchronous are mutually exclusive notions.

*USB initiates a transfer with a specific device with of one of four types: bulk, control, interrupt, and isochronous.* Bulk transfers are not time-critical (USB hard drives) and frames will be retransmitted when an error is detected.

With isochronous transfers, a certain amount of bandwidth is allocated on the host to accommodate the frames/bits required per second by the audio stream. DACs could detect errors but frames will not be retransmitted. But what defines the notion of a “second”?

With synchronous USB, the clock resides on the host (your PC, server, etc). With asynchronous USB, the master clock typically resides on the DAC. The DAC tells the host when to send the packets which essentially defines what a “second” means. This way audio data is “packaged” and streamed properly and the DAC never misses a sample. This does not ensure the integrity of those incoming bits, however, it just guarantees a specific rate using the presumably more accurate/consistent master clock on the DAC.
...
The USB standards themselves don’t even take into consideration the inductance or capacitance of a cable, which really only affects an audio or video signal.
...​
https://audiobacon.net/2017/09/18/curious-cables-usb-review/

*So write up a point by point response of where he's getting USB audio transfer methodology wrong - that would be super useful!*

Help us all understand the USB spec when comes to computer audio transfer - show us where this guy is wrong.


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## GrussGott (Jul 22, 2018)

Phronesis said:


> perception is unreliable to the extent that large differences may be perceived to exist which do not actually exist.



Yes, and it's also a fact that we don't fully understand how or what the human ear hears, processes echos, timing queues, frequencies, etc, nor can we perfectly measure audio.

So we're stuck: we know human perception can be unreliable and we also know we can't say for a fact what should or shouldn't be heard.

That doesn't sound like a good recipe for presenting an opinion as a conclusive science fact.


----------



## Steve999

Now that's a discussion worth having. This is what Stephen Colbert calls "truthiness"--it sounds like it could be true but in fact it's something that sounds like the truth to skate past a myriad of untruths.

Where he's getting it wrong is discussing what goes on at either end of the cable once you get past the cable. The cables themselves make no difference as long a they are in spec. Intentionally or not, he is feeding you B.S. in support of a snake-oil industry.

Here are a couple of serious articles on the matter. Good design engineering past the ends of the cable fixes it. What USB cable you use, as long as it is in spec, is irrelevant.


http://www.electronicdesign.com/embedded/achieving-bit-perfect-usb-audio

https://www.edn.com/design/consumer...-with-care--Scary-stories-from-the-test-bench



GrussGott said:


> So you're disagreeing with this author's explanation of USB file transfer versus USB audio transfer?  Where's he getting it wrong?
> 
> *Asynchronous & Isochronous Basics*
> Isochronous refers to the _transfer type_ and asynchronous USB essentially refers to the location of the master clock (who controls the clock?). In the context of USB, isochronous and asynchronous are mutually exclusive notions.
> ...


----------



## GrussGott (Jul 22, 2018)

Arpiben said:


> Here are a couple of serious articles on the matter.



Sweet, now we're cookin!  I'll check 'em out, but how about a quick summary in your own words for everyone?

EDIT: ok so I just read both articles and

article 1 describes how a vendor can test their USB spec implementation audio quality:

_"*A modern mobile audio accessory is a spaghetti-fest of code, and innocent changes to an interrupt priority here and a DMA descriptor there can subtly change the behaviour of your system at the margins.* Swap your release candidate designs between teams and buy them beer, or tea, or whatever, if (when!) they find the failure points."_​
and article 2 describes the spec no different from the link I provided:

_In asynchronous mode, the master clock is provided by a separate clock source locally (Fig. 5). *This mode allows for clocks to be as clean as development time and production cost can allow for the system. *

"The asynchronous approach using a PLL provides low-jitter clocks with no locking or synchronization issues. However, using this mode adds another level of complexity to the buffer-management aspects of the system. That’s because the local crystal oscillator is not necessarily locked on to what the host thinks is 48 kHz. The tiny mismatches in frequencies will eventually lead to an over/underflow, causing audible pops if left alone."_​What'd I miss?

Maybe you should point out the exact place where the audiobacon author gets the spec or theory wrong with a corresponding passage from your articles


----------



## Steve999 (Jul 22, 2018)

[Edit in the spirit of Phronesis.]

Wrong:

"It’s apparent the quality of the material and geometric design used for a USB cable is correlated to the level of signal deformation."

It is not apparent and seems very highly unlikely. Under prevailing theory if the USB cable is in-spec for its use, the particular USB cable used makes no difference. It is trasmitting the ones and zeros in the same manner and with the same timing as any other in-spec USB cable would. This is the point where he pulls his sleight of hand (or demonstrates his lack of understanding) and moves on over into the world of audio cable snake-oil.




GrussGott said:


> Maybe you should point out the exact place where the audiobacon author gets the spec or theory wrong with a corresponding passage from your articles


----------



## Phronesis (Jul 22, 2018)

donunus said:


> All I did was have a friend swap the cables covered in black cloth labeled numbers 1-4. I took notes of the sound of each number and guessed which cable it was based on listening to all of them previously. Music played were ones I was familiar with and I chose the music to play while he swapped cables every minute or so and played the same track for each cable. He played 5 tracks for me in total. I Identified which cable was which. I think my conclusion was that for my sub 1000 dollar headphone setup, a 20 dollar belkin gold was fine but was definitely a worthy improvement over a cheap freebie to my ears. I had an expensive cable included that sounded different as well but felt that it actually didn't do much more for me in terms of musical enjoyment. Another one was an audioquest cable which was also decent FWIR but I can't remember all the details of my notes anymore. This was a few years back. I bought the belkin gold, a 20 dollar no brainer and never thought much more about it.



If I understand correctly, you were able to identify four cables based on sound alone, using a variety of tracks.  If there were no substantial flaws in your methodology and interpretation of results, I can see why you would consider that to be compelling evidence.

It happens that I need a longer lightning-to-USB cable, so maybe I'll pick up a $20 Belkin gold too. Unlikely that it sounds worse than other cables, and even if it doesn't sound better, there no real risk or loss involved in spending $20 on it when I need a cable anyway. 



GrussGott said:


> Yes, and it's also a fact that we don't fully understand how or what the human ear hears, processes echos, timing queues, frequencies, etc, nor can we perfectly measure audio.
> 
> So we're stuck: we know human perception can be unreliable and we also know we can't say for a fact what should or shouldn't be heard.
> 
> That doesn't sound like a good recipe for presenting an opinion as a conclusive science fact.



I do think we're kind of stuck, and unlike many others in this forum, I see even blind tests as suffering from a significant issue with respect to always comparing a sound being heard in real time vs a sound recalled from memory.  I don't see a way around that, since we can't compare two sounds simultaneously.  It's not like double blind trials in medicine, where we can compare the results of a drug vs placebo by randomly assigning each to separate groups of people and then comparing outcomes.

I also agree that we can't necessarily assume that particular measurements will necessarily encompass everything that could matter with respect to perception - maybe we can rely on measurements to capture big stuff, but they could conceivably miss subtle stuff.

So, like real scientists, I think we need to get away from confidently claiming that we have 'conclusive scientific facts' and instead recognize that there are some uncertainties, exercise some judgment to think in terms of likelihoods, and accept that there will be debates and disagreements until there's a large enough body of evidence to put the debates to rest.


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## Steve999 (Jul 22, 2018)

Wow, excellent point, I hadn't thought of that. I bet if we were somehow able to perceive both audio samples separately in real time without resorting to audio memory we would be able to be more sensitive and discerning between the two samples, to one degree or another. How much more we can only speculate. And we really are stuck in that sense because that is physically impossible.



Phronesis said:


> I do think we're kind of stuck, and unlike many others in this forum, I see even blind tests as suffering from a significant issue with respect to always comparing a sound being heard in real time vs a sound recalled from memory.  I don't see a way around that, since we can't compare two sounds simultaneously.  It's not like double blind trials in medicine, where we can compare the results of a drug vs placebo by randomly assigning each to separate groups of people and then comparing outcomes.


----------



## Phronesis

Steve999 said:


> Wow, excellent point, I hadn't thought of that. I bet if we were somehow able to perceive both audio samples separately in real time without resorting to audio memory we would be able to be more sensitive and discerning, to one degree or another. How much more we can only speculate. And we really are stuck in that sense because that is physically impossible.



It's actually even worse than that.  If we're comparing what we're hearing in real time vs what we're recalling from memory, the two can presumably be interfering with each other.  And if we're comparing two things recalled from memory (neither in real time), the two memories can still interfere with each other, and the sequence in which they were heard could also influence the comparison.  The time dimension is a fundamental problem with audio comparisons.


----------



## bigshot (Jul 22, 2018)

hat doesn't mean that I would hate it if someone proved part of my beliefs to be incorrect. On the contrary, I would be very excited by that. It would make my day, because I would get the opportunity to learn something new. Over the past couple of decades, I have been wrong about a lot of things. But I was open to being proved wrong. And when it was proven to me, I unceremoniously dropped my misconception and moved forward with the new truth. However, when I have seen something proven time and time again, I require tighter controls and more documentation before I'll accept my error.

When it comes to USB cables sounding different, there is no reason to assume that they do. Digital transmission is pretty much an all or nothing thing. USB cables are designed to perform within specs that guarantee accurate transmission. If we are eliminating defects in design or manufacture from the mix, then your impression is saying that everything we know about USB cables must be wrong, and the people who designed the standard must have made huge errors when they created it.

If you want to prove that properly designed and manufactured USB cables sound different from each other, you have a large burden of proof. I'm open to it. I would be thrilled to know all about it. But you are going to have to adhere to the strictest controls if you want to prove something that is that firmly established is dead wrong. If you want to be the one that proves it conclusively, there are people here who will be happy to help you and provide advice for how you do that. Just ask.

If you don't want to go to all that trouble, and you just want to believe what you believe, that is fine too. Feel free to believe whatever you want. Just don't expect people who have gone to the trouble to research and test things themselves in the past to validate your belief. Here in sound science we get to call the "put up or shut up" of documented evidence to prove claims. That's what science is about. This is the one thing that sets us apart from the rest of Head-Fi.

There are people in the rest of Head-Fi who know a lot of things and are very smart. But you can know a lot of things and be smart... and be dead wrong because of bias, sloppy testing and incorrect assumptions. Here in sound science, we're subject to those errors too. We just have a process for rooting that out. If you're uncomfortable with that process as some people here are, and it makes you mad or belligerent, or cranky, this forum isn't the best place for you. We aren't going to abandon our process to make you feel better.


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## bigshot (Jul 22, 2018)

donunus said:


> All I did was have a friend swap the cables covered in black cloth labeled numbers 1-4. I took notes of the sound of each number and guessed which cable it was based on listening to all of them previously.



What were you listening for and what was the difference you heard? If a USB cable isn't transmitting digital audio accurately, you will hear pops and clicks or the stream will drop entirely. I've experienced that with optical cables and HDMI cables with kinks in them. The HDMI went back into handshake mode and started flashing a blue screen on my monitor. These are all signs of a defective or damaged cable. However if the difference you observed was something like "veils over the sound" or "deeper soundstage" those are red flags for bias. And things like "warmer sound" or "reduced treble detail" would indicate a change in response that would be easily measured and very unlikely since digital audio isn't subject to the same sort of errors as analogue. If you guessed correctly and you eliminated the possibility of a defective cable, I would suggest that you would need to do more trials to increase the statistical odds. I would also ask you to check to see if you could identify each of the other cables individually. Were they all different? Or was just one of them different? If just one of them was different and was easily identifiable over multiple trials, the next step would be to submit that cable for measurement to determine why it is different.



donunus said:


> So far as the engineering explanation is concerned, there are things everywhere on the internet explaining why USB cables sound different but it is not really useful information if a certain person can't hear the differences anyway. So I suggest everyone just listen and throw biases away then make their own decision if the differences are significant enough to bother obsessing about



The only reason to ask "what?" is to lead to the answer to the question "why?" Again, you are in sound science, not the rest of Head-Fi. We don't stop at just coming up with a subjective impression and leave it at that. We want to know the reason and we want to quantify the amount objectively.


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## sonitus mirus

A letter responding to folks on this site from USB.org.

http://thepenguin.eu/2018-01-19-audiophile-usb-cables/


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## bigshot (Jul 22, 2018)

Phronesis said:


> I see even blind tests as suffering from a significant issue with respect to always comparing a sound being heard in real time vs a sound recalled from memory.  I don't see a way around that, since we can't compare two sounds simultaneously.



Direct A/B switchable, line level matched. I was able to compare SACD to CD by lining up two players side by side playing the same disc with the same mastering on the SACD and CD layer. It took a few tries to get it started in sync, but once they were in sync, I could switch back and forth as fast or slow as I needed and could directly compare one to the other.


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## bigshot (Jul 22, 2018)

sonitus mirus said:


> A letter responding to folks on this site from USB.org.
> http://thepenguin.eu/2018-01-19-audiophile-usb-cables/



We have a winnah! Give that man a baby doll!

This link is great not just because it tells us that every USB cable certified and properly manufactured sound sound the same, but because it also tells us how USB works and what to listen for to detect USB errors. It doesn't seem to be too difficult to tell if a cable is working properly or not. That tells us that perceived subtle differences between cables are most likely errors in testing procedure or bias creeping in.


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## sonitus mirus

bigshot said:


> We have a winnah! Give that man a baby doll!
> 
> This link is great not just because it tells us that every USB cable certified and properly manufactured sound sound the same, but because it also tells us how USB works and what to listen for to detect USB errors. It doesn't seem to be too difficult to tell if a cable is working properly or not. That tells us that perceived subtle differences between cables are most likely errors in testing procedure or bias creeping in.



But there is no explanation for USB cables providing better instrument separation or a warmer sound.


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## chef8489 (Jul 22, 2018)

sonitus mirus said:


> But there is no explanation for USB cables providing better instrument separation or a warmer sound.


A USB cable does not alter the data and can not change these characteristics. A USB cable is a transport for the digital signal to go from point a to point b where it is converted by the dac from a digital to analogue, where filters are applied that can alter the sound. If the digital signal is not altered there can be no change in those characteristics. If there were it would be measurable.


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## sonitus mirus

chef8489 said:


> A USB cable does not alter the data and can not change these characteristics. A USB cable is a transport for the digital signal to go from point a to point b where it is converted by the dac from a digital to analogue, where filters are applied that can alter the sound. If the digital signal is not altered there can be no change in those characteristics. If there were it would be measurable.


I could get into how science doesn't measure everything and human hearing perception is barely understood in some ridiculous rant on the fringe of being rational, but I'll just let you know that I was being sarcastic.   I agree with your position wholeheartedly.  I could not find an eye roll emoticon, so I went with speechless.


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## GrussGott (Jul 22, 2018)

Steve999 said:


> [Edit in the spirit of Phronesis.]
> 
> Under prevailing theory if the USB cable is in-spec for its use,



Yet your articles point out that receiving chips, like all computer systems, are design limited and if those limits are exceeded errors result.

It comes down to two things:

(1.) If a square wave is impacted by EMI in transmission such that, say, a transmitted voltage representing a 0 is actually measured on the receiving end as a 1, how does the receiver deal with that?

(2.) And then, if the receiver expends resources to deal with missed bit, what happens when those resources are maxed out?


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## chef8489

sonitus mirus said:


> I could get into how science doesn't measure everything and human hearing perception is barely understood in some ridiculous rant on the fringe of being rational, but I'll just let you know that I was being sarcastic.   I agree with your position wholeheartedly.  I could not find an eye roll emoticon, so I went with speechless.


Lol ok. But so many think the opposite. That's why they sell 1,00.00 USB cables and people buy them. Because they give better soundstage and a warmer sound. Lol. I have kept quiet for a while. , guess I will go back into the shadow again.


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## GrussGott

chef8489 said:


> A USB cable does not alter the data and can not change these characteristics. A USB cable is a transport for the digital signal to go from point a to point b where it is converted by the dac from a digital to analogue, where filters are applied that can alter the sound. If the digital signal is not altered there can be no change in those characteristics. If there were it would be measurable.



What happens if a transmitted voltage is altered by EMI in transit and thus mis-read on the receiving end?  Is that impossible with all in-spec USB cables?  And, if not, what happens in that case?


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## bigshot (Jul 22, 2018)

If the DAC at the receiving end isn’t capable of accurately reconstructing the signal being transmitted by a properly functioning usb cable, that isn’t the fault of the cable. It’s the fault of the DAC. USB cables are shielded. As long as you don’t live in Hoover Dam that should be fine. If someone is receiving errors due to interference, I would like to know what the usb cable is plugged into. That is probably the source of the problem. I’m just as interested in finding out about DACs that are designed and manufactured out of spec as I am lousy cables. I haven’t found that either of those things are common enough for me to run across one yet, but I’m still looking.


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## chef8489 (Jul 22, 2018)

GrussGott said:


> What happens if a transmitted voltage is altered by EMI in transit and thus mis-read on the receiving end?  Is that impossible with all in-spec USB cables?  And, if not, what happens in that case?


That is a different situation than what I was referring to. In that case you get clipping or skipping. It would have to be pretty strong EMI, but some cases it does happen. We have talked about this. In a situation like that it does not matter what the data is. The data is corrupted. A better cable might have helped, or a shielded cage with the wiring going through should work. I doubt anyone here would be in this situation though as it would take some serious emi.


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## Phronesis

bigshot said:


> Direct A/B switchable, line level matched. I was able to compare SACD to CD by lining up two players side by side playing the same disc with the same mastering on the SACD and CD layer. It took a few tries to get it started in sync, but once they were in sync, I could switch back and forth as fast or slow as I needed and could directly compare one to the other.



The problem remains that a memory of sound is being compared to something being heard in real time.  No way to avoid it.

More generally, any listening comparison, whether blind or not, is using subjective human perception as the 'measuring instrument', with its associated problems.  Matching volumes and music segments, controlling switching time, etc. will change how perception operates and may reduce some of the problems with perception by mitigating problems of memory, expectations, etc., but it can't eliminate them - you still have complex and fallible human perception at the end of the chain.

IMO, for the components in the chain prior to transducers, it may be best to rely on measurements to evaluate equipment, even if measurements have limitations.  Once we get to sound waves in the air, things get more complicated, and even more so when sound waves become auditory nerve signals, brain states, and mental perceptions - I think we need to use listening comparisons there, even if they're problematic.


----------



## Phronesis

Side note: I learned the phrase "Gruss Gott" when we were on honeymoon in Europe decades ago.  Pretty cool to run across it again!


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## GrussGott (Jul 22, 2018)

sonitus mirus said:


> A letter responding to folks on this site from USB.org.  http://thepenguin.eu/2018-01-19-audiophile-usb-cables/



Uh huh, and here's what that USB dude says in his 2011 letter:

_USB supports isochronous transport which is a timely delivery of data. The
isochronous transport has guaranteed bandwidth on USB. Isochronous
protocol, however, does not support error recovery. In other words, if data
is flagged as an error by the receiver, there will be no attempt at data
retransmission. So if the receiver is using the isochronous protocol, *then
there can be errors in data*. Most webcams use the isochronous transport.
*High-end audio/video *equipment that does not mandate real-time delivery of
data* should not use the isochronous transport because accurate data delivery
is not guaranteed.*_​
...
_*Most USB audio/video devices use the bulk transport *because real-time
delivery of the data is not necessary_.​
And *within the context of not using isochronous transport for audio, but bulk*, your 2011 dude recommends walmart USB cables. makes sense.

But 2018 audio devices don't appear to use his recommended "bulk" transport for USB audio transport streaming playbck, but rather the unrecommended isochronous transport ...  Because even back in 2012 the EDN dudes say

_*USB Audio uses isochronous,* interrupt and control transfers. *All audio data is transferred over isochronous transfers*; interrupt transfers are used to relay information regarding the availability of audio clocks; control transfers are used used to set volume, request sample rates, etc.





_​And last August 2017 the android dudes say

_*USB audio uses isochronous transfer mode *for its real-time characteristics, *at the expense of error recovery.* In isochronous mode, bandwidth is guaranteed, and data transmission errors are detected using a cyclic redundancy check (CRC). *But there is no packet acknowledgement or re-transmission in the event of error.*_​So I guess PC/mobile USB audio uses isochronous mode, which was not recommended by your USB folks, thus making their cable recommendations irrelevant to us for streaming playback because in isochronous a missed bit is a missed bit ... there's no retransmission as is the case in bulk which is used for file transfers.

Seems like your linked content doesn't apply then, or only applies to people using USB bulk for audio transport (i.e., streaming playback) which isn't any of us?   But please correct me if I'm misreading.


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## GrussGott (Jul 22, 2018)

Phronesis said:


> Side note: I learned the phrase "Gruss Gott" when we were on honeymoon in Europe decades ago.  Pretty cool to run across it again!



Wow, that was probably a fantastic honeymoon, congrats!  Beautiful part of Europe!  I used to do a lot of work with some Siemens engineers out of Munich and so i was always saying that on answering the phone and my US colleagues started calling me that as a little joke so ... that's the back story


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## GrussGott

edit error - can we not delete posts?


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## bigshot

Phronesis said:


> The problem remains that a memory of sound is being compared to something being heard in real time.  No way to avoid it. More generally, any listening comparison, whether blind or not, is using subjective human perception as the 'measuring instrument', with its associated problems.  Matching volumes and music segments, controlling switching time, etc. will change how perception operates and may reduce some of the problems with perception by mitigating problems of memory, expectations, etc., but it can't eliminate them - you still have complex and fallible human perception at the end of the chain.




The purpose of controls is to reduce variables to just the things that are relevant to your test. If you want to eliminate the variable of human perception, you just look at measurements. But if your test is to establish if something is audible to human ears for the purposes of listening to music in the home, a direct A/B switched, line level matched blind comparison is more than adequate for determining if a difference is audible or not. In fact, a comparison test like that is more controlled a situation than the circumstances we are in when we listen to music in our living rooms.


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## sonitus mirus

GrussGott said:


> Uh huh, and here's what that USB dude says in his 2011 letter:
> 
> _USB supports isochronous transport which is a timely delivery of data. The
> isochronous transport has guaranteed bandwidth on USB. Isochronous
> ...




Doesn't seem to make any audible difference that anyone has been able to prove.

http://www.realhd-audio.com/?p=5971


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## Phronesis (Jul 22, 2018)

bigshot said:


> The purpose of controls is to reduce variables to just the things that are relevant to your test. If you want to eliminate the variable of human perception, you just look at measurements. But if your test is to establish if something is audible to human ears for the purposes of listening to music in the home, a direct A/B switched, line level matched blind comparison is more than adequate for determining if a difference is audible or not. In fact, a comparison test like that is more controlled a situation than the circumstances we are in when we listen to music in our living rooms.



The problem I see is that our perception, when used as a measuring instrument, is variable and somewhat unreliable, and involves the complexities of operating at both conscious and subconscious levels.  Moreover, controlled testing conditions are generally quite far from normal listening conditions, so we can't necessarily generalize results from test conditions to normal listening conditions.

That said, my best guess is that the vast majority of differences people perceive between gear other than transducers are due to misperception rather than real differences in signals and sounds, so those differences are actually either negligibly small or non-existent.  If people would try introducing controls and quick switching for themselves, as you and I and many others have done, they would likely reach that conclusion.

I personally am not much interested in really tiny differences.  It seems a lot more useful to focus on the things that are known to make a big difference.


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## sonitus mirus

I'd like to see someone run a test with a generic 3 meter USB cable and see how many isochronous errors were found transferring test data at full capacity over USB 1.0 and 2.0.  I don't expect that there would be more than 1 error in a 24 hour period, if any at all.  If someone can show that errors are an issue, then we can discuss if the cable is the likely culprit.  Assuming that full USB transfer rates are typically significantly higher than practically every popular audio format and 3 meters is probably a much longer cable than most people use when connecting a DAC to a PC or phone/device, it is very unlikely that USB cables matter.


----------



## castleofargh

GrussGott said:


> Thanks for supporting me! I couldn't agree more except to add that "he" should also disclaim when giving advice whether they're doing so as a trained, experienced digital signals scientist or purely as a hobbyist.  As you point out, I've provided all of the evidence to back up every claim I've made: I heard it, and told you my understanding of why it happens.  I even included pictures!  *If you believe that to be only half understood,* *please provide the other half!  *Feel free to reply to my post with the pictures and fill in the blanks ...
> 
> Maybe the completed result could even be a product of this sub-forum we share to help others?
> 
> ...



let's start by the beginning:

- you decide that a sighted test is a valid listening test. boom you're out. we can make long lists of what you got wrong, but what's the point when your very axiom relies on a mistakes?
this is my go to link because I feel that he explains it well enough in a simple enough way http://seanolive.blogspot.com/2009/04/dishonesty-of-sighted-audio-product.html
Toole really started to clarify those issues on speaker impressions and to offer solutions in books and peer reviewed papers, sadly it's AES stuff. "money money!"
but it's not exactly new that sighted tests are full of flaws, and that the smaller the differences, the more unsuited it is as a test method. trying to argue about other stuff while dismissing that issue makes no sense to me.

basically, if your purpose was to say "hi, I felt something when I changed the cables". well, good for you. this probably belongs to the appreciation topic about the cable you like best and will be wonderful confirmation bias for all the owners who will love you for saying it. but the total objective value of that information is you saying "I like that one best". we don't know why. maybe it's sound, maybe not. nothing in your "experiment" clarifies even that. it's how bad your listening method is, you get out of it without even being able to confirm that sound caused your impressions. you don't have to do more if you don't want to as a casual audiophile, but you get the conclusive evidence and the respect your experiment deserves. zero objective information about sound, and some gut feelings most people don't really care about outside of a subjective review or the appreciation topic for the cable. in a technical discussion about the objective impact caused by USB cables, it's basically unhelpful noise.




- the objective information you bring up tells nothing about the potential magnitudes or probabilities such events could have on a typical cable and typical DAC. in fact what you provide doesn't really explains why it's the cable that would solve most of those potential issues, or how.
somehow you seem to imagine that random radio noises will generate a 1V DC signal or something. unless you're in a very special situation, the noise getting through the shield will be super tiny voltage. the worst it usually does is very slightly modify the overall voltage of the signal so the receiver will be triggered a tiny moment before or after. that alone can hardly become audible as is, but all modern DACs can handle some async system and have fancy reclocking, upsampling, buffers, sometime proprietary stuff and what not . to attenuate or completely eliminate such issues. the notion that if my cellphone is on the table then all the 0 in the audio signal will become 1 anytime it's sending something, is completely unrealistic.
in practice, error are very rare. and of course they are, the moment you start getting regular errors, you will end up with codes other than the audio signal being corrupted, like the very request for the next packet depending on which device is "master". and that will soon screw up with the  computer and probably just cut off the signal. it's like good old analog TV signal vs digital TV signal. with analog we could have a cloud of noise over the picture and it would still go on, showing whatever the signal was no matter how corrupted. at the start of digital TV, the smallest hiccup would get a frozen picture of some horrible giant "pixel" like artifacts. the idea that the consequences of repeated digital error would somehow be a slightly lower quality music isn't realistic. also we have to consider the magnitudes involved, the "noise" would have to be high enough to trigger the wrong value, but also small enough so that just a tiny attenuation from some fancy overkill shielding in the cable will put us back to getting the right code. noise below that tiny window of amplitude and the special cable wouldn't change anything. noise above and we would still get the errors. and we're not talking shielding or no shielding. we're talking shielding or fancy shielding from audiophile cable doing whatever. the improvement is unlikely to be extreme or necessary.

but more than anything, you keep running after confirmation bias and anything that might justify why you feel a change. you should stop that and try instead to concern yourself with first making sure the perceived change is in the sound. maybe measure a few stuff to make sure your system performs within expected fidelity. then you could start playing around and try to diagnose your system to find out what specific objective change is involved in that audible change. but your random fishing for an objective reason to be right, that's never going to work. even if you find something credible, there is still nothing saying that it applies to your situation and nothing saying that you didn't make up the change in your head. you cannot completely substitute bad testing practices with cherry picked signal theories and hope it will stick. it's the guy getting the right answer in math using a double error in his calculus. nobody deserves points for that. 

for example, I usually buy several super cheap cables from various brands, measure a few stuff with them and get rid of the ones showing weird behaviors and bad measurements. which admittedly happens from time to time. I haven't found the result to sound audibly different, but if it might, surely such cables were ideal candidates to pass a blind test as they really measured poorly. 
otherwise, I pretty consistently have more variations from plugging the cable in a different USB port or computer or power hub, than from switching between my cables. just to put things in proper perspective.
 I honestly don't know what a "better" USB cable is supposed to be. I don't know if audiophile stuff are just good typical USB cables, or eye candy, or random cable and marketing BS? or if they're high speed cables, or maybe the opposite and they have a very early low pass effect they consider a good thing as it filters out more high frequency noises? IDK. I haven't seen any clear technical literature and feel that there is no actual concept of fidelity associated with the "audiophile" label on cables.
anyway, right now my DACs and ADCs give measures real close to the manufacturers measurements, so I have no reason to suspect that my cables are just all equally bad. more likely they're all pretty fine. 
now if you want to send your "better" cable to me for a few days, I'll bother testing what I can and maybe my conclusions would give you credit. IDK. or maybe send stuff to @amirm if he cares and has the time. as you seem to trust him maybe the results would be more relevant to you. (I'd advise against sending me a bomb, it probably wouldn't pass customs.^_^)




- trying to force Greg to prove that a cable can't ever change the sound, man what a precious strawman. do you think presenting the opposing party with some impossible to prove challenge is going to make people go "hey, Greg can't prove it so whatever BS the other guy was supporting must be true"?
that made me laugh. 





about the section of the forum being public. I believe I've explained myself clearly enough in my last post. maybe read that part again. this section was literally created so that people would have a place to discuss controlled testing, biases, placebo, and be able to take an objective approach to things without people around starting to go crazy. it was given so people would stop discussing those stuff in the other sections. it's not a private section, but if you're on a fishing forum and you don't care about them fishes, you probably shouldn't post on that forum. isn't it just common sense?
if you don't get it, just go in the cable section and contest every auditory claim you read, systematically ask for blind test and measurements. see how that will be received and how open minded and welcoming they are about it. after a few days come back here if you didn't get a perma ban and tell me again about private forums and how people treat you. 




and I wrote a book. ... it's a disease, I need a prescription of medical Pringles to calm down or something. .


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## donunus (Jul 22, 2018)

Reply to bigshots last reply to my post...
If you are asking about the engineering side, I have read quite a few times that usb realtime audio playback doesn't work the same way as using cables to just copy files from one end to the other. The timing issue matters FWIR. That probably explains the sonic differences. I can't say for sure but dropouts would probably mean more than just a bit or two of loss and is usually corrected by setting buffers etc but the sound with the different cables with same buffer settings on the computer is not just about dropouts. The music actually sounds like its more liquid, more analog if I were to use more generic terms. I had details of what to listen for in the exact songs I used but It wasnt like an mp3 vs lossless comparison where you would usually wait for parts with extreme transients to clearly detect differences besides the high frequency extension differences.


----------



## chef8489

donunus said:


> Reply to bigshots last reply to my post...
> If you are asking about the engineering side, I have read quite a few times that usb realtime audio playback doesn't work the same way as using cables to just copy files from one end to the other. The timing issue matters FWIR. That probably explains the sonic differences. I can't say for sure but dropouts would probably mean more than just a bit or two of loss and is usually corrected by setting buffers etc but the sound with the different cables with same buffer settings on the computer is not just about dropouts. The music actually sounds like its more liquid, more analog if I were to use more generic terms. I had details of what to listen for in the exact songs I used but It wasnt like an mp3 vs lossless comparison where you would usually wait for parts with extreme transients to clearly detect differences besides the high frequency extension differences.


Data across an USB cable is the same no matter if it is a file or music. It is still a 1 or a zero. It is no different than transferring a file to a printer or transferring a video file. Until the 1 or 0 is decided or converted by the opject ie printer, dac, or whatever, it is just a digital file represented by a 1 or a 0.


----------



## donunus

data is the same but according to reports from people in the industry, the timing the data is sent for real time playback affects sound quality. This is why people buy reclockers for example. As for me, if you check what I have done before, I did hear the differences although not huge but it was there and the differences were consistent between the cables.


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## GrussGott (Jul 22, 2018)

castleofargh said:


> let's start by the beginning:


Or we could discuss the topic of the thread - USB audio.  That said, I'm happy to participate in a thread dedicated to all of the off-topic stuff you listed, just let me know where.



sonitus mirus said:


> Doesn't seem to make any audible difference that anyone has been able to prove. http://www.realhd-audio.com/?p=5971



Ok, we're getting somewhere!

*(1.) USB audio streaming relies on the USB-IF Audio Class which uses isochronous transfer mode*, the one that can't recover from errors, unlike data file transfer which use bulk mode.

*(2.) So we need to pick from 3 isosych sub-modes: asynchronous, adaptive, and synchronous.*  Hopefully it's not controversial to say asynchronous is preferred as it allows the DAC to be the master clock, so any decent external DAC is iso-asynch

So why is isochronous-asynchronous - letting the DAC be the master clock - important?

As I understand it, Jitter.  It's not only important that all the 1s and 0s arrive intact (which in async mode they might not) _but that those bits arrive on time ... _because we're talking live music samples, say 44/16, and we expect the DAC to translate those square waves into sine waves.  To do that, the DAC needs to know exactly when to make the sample voltage X volts - if the DAC sets the analog sine wave voltage at -2.05v slightly before or after the source, it may not sound right because you just changed the analog wave from the source analog wave.

In other words, if any of these measurements don't arrive correctly or on time then you hear it:






So, yeah, I guess we just have to wonder *how plausible it is that these allowed errors can't ever be heard?*
and if we think maybe they could, then the question is, is it plausible a well designed USB cable could help prevent them more than a base-spec one?

Where I think we all agree is that cables are the last place to go for sound improvements ... but for me it's plausible they could help.


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## GrussGott (Jul 22, 2018)

chef8489 said:


> Data across an USB cable is the same no matter if it is a file or music. It is still a 1 or a zero. *It is no different than transferring a file to a printer or transferring a video file. *Until the 1 or 0 is decided or converted by the opject ie printer, dac, or whatever, it is just a digital file represented by a 1 or a 0.



No sir, you need to read the USB specs.

*If you connect a DAC to your PC* that "enumerates" as part the USB Audio Class, it *sets the USB data transfer mode as "isochronous" which means errors are not corrected*, which means your DAC live converts those errors to analog sine waves, which means your amp gets the errors, which means your headphones do, which means you do*.

USB Spec:
_An essential issue in audio is synchronization of the data streams. Indeed, the smallest artifacts are easily detected by the human ear. Therefore, a robust synchronization scheme on isochronous transfers has been developed and incorporated in the USB Specification. The Audio Device Class definition adheres to this synchronization scheme to transport audio data reliably over the bus._​
*If you connect a USB drive*, then it enumerates as mass storage, *which sets the USB transfer mode to "bulk", which DOES allow for error correction*, meaning the receiving device checks for errors and re-asks for data until no errors are present.  This is why data files are always exact duplicates.

*NOTE: the spec provides for some assistance with jitter via clock feedback, and while isochronous does check for errors, it has no ability to request errored-out data


So the question is, Chef, do you think those uncorrected errors your DAC just got aren't audible, and never will be?


----------



## chef8489

GrussGott said:


> No sir, you need to read the USB specs.
> 
> *If you connect a DAC to your PC* that "enumerates" as part the USB Audio Class, it *sets the USB data transfer mode as "isochronous" which means errors are not corrected*, which means your DAC live converts those errors to analog sine waves, which means you amp gets the errors, which means your headphones do, which means you do.
> 
> ...


Again you missed the point i was making. Yes there is a difference between isochronous and bulk. My point is the data is identical. Whether it is corrected or not was not my point. My point was that it is a 1 or a 0 till whatever device decodes or converts the 1 or a 0 into a audio file, video file, picture, document or whatever. Just as the cable can not change the picture making it more vibrant  or making the video a higher definition than it started off, you can not get better separation or wider sound stage or better highs or deeper bass. 

If you have a faulty cable what you can get is lost data resulting in clips, skips, sometimes artifacts  or total loss of music. If you have a bad ground that might transfer over the usb cable and the DAc does not filter it out you can get noise over on the analogue side of the dac. This is not the USB cables fault most of the time but the hardware.


----------



## GrussGott (Jul 22, 2018)

chef8489 said:


> Again you missed the point i was making. Yes there is a difference between isochronous and bulk. *My point is the data is identical.*



Chef, if the data transmission errors aren't corrected for, then it's not identical.

For example, if you USB-bulk mode a FLAC file from PC to PC, the received file will be an exact copy due to the error correction of USB bulk mode.

If, however, if you hit play on iTunes on that same FLAC file and _*live stream it *_over USB in isochronous mode to your DAC, the DAC will likely NOT have an exact copy due to inevitable transmission errors.

It's not the same.  You will not hear the same file.


----------



## chef8489

Again you are missing my point. The data, the pictures, music, files are all 1,s and 0's. that is what I am saying Not the data received and transmitted are identical if errors. The cable does not differentiate between music, photos, files, word documents. There is no way for a cable to make changes to those files to make the picture more vibrant, the video have more definition or a sharper picture, the music to have more detail, instruments to have more separation or more warmth. That was my point. The cable sees these files identically.


----------



## donunus

chef8489, pictures load before viewing while music plays as it is streaming through the cable. There is no timing issue with a picture being viewed because it is preloaded.


----------



## GrussGott (Jul 22, 2018)

chef8489 said:


> Again you are missing my point. The data, the pictures, music, files are all 1,s and 0's. that is what I am saying Not the data received and transmitted are identical if errors. The cable does not differentiate between music, photos, files, word documents. *There is no way for a cable t*o make changes to those files to make the picture more vibrant, the video have more definition or a sharper picture, t*he music to have more detail, instruments to have more separation or more warmth*. That was my point. The cable sees these files identically.



Yeah, I just explained why that's not true by using the actual USB spec:

(1.) If your DAC enumerates as USB Audio class it will select isochronous data transfer mode - live stream and no error correction
(2) If you have have a decent DAC, it will select the asynchronous sub-mode which means the DAC controls the clock (this helps with jitter errors)
(3.) Live transmission of, say, a 44/16 will begin, and there will be errors, and those errors won't be corrected for
(4.) The DAC will live convert those errored bits into an analog sine wave
(5.) You may hear the effect of those errors.

 There's a lot places those errors can come from, but one of them is interference through the cable.

That said, there are many architectural ways to design a cable to minimize transmission errors: separate the power, shielding, etc etc.  Some of these are in the USB spec, some are recommended but not required, some seem to empirically work, and some are complete garbage / BS / snakeoil.

Net-Net:
If the cable prevents live-stream errors that otherwise would've gotten through, that very well may sound to you like warmth or staging or whatever.  Very possible, which is why the USB spec has cable requirements, and cable recommendations, and why they specifically have an audio class spec.

The fact that the errors are there is not even a question, and they may have gotten in via your cable, but can you hear them?

We've established we can't conclusively say since we have way of quantitatively stating what Chef SHOULD hear on this day, at this time, with this gear.


----------



## chef8489

donunus said:


> chef8489, pictures load before viewing while music plays as it is streaming through the cable. There is no timing issue with a picture being viewed because it is preloaded.


Music does not stream through the cable. Data is transferred through the cable. It is then turned back into music by the dac.


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## donunus (Jul 22, 2018)

data is streamed through the cable in real time while the music is playing.
EDIT: Nice try with the philosophical trolling though. Props for that lol


----------



## GrussGott (Jul 22, 2018)

chef8489 said:


> Music does not stream through the cable. Data is transferred through the cable. It is then turned back into music by the dac.



Exactly, your DAC converted ERRORED data into analog sine waves WITH ERRORS (music) that is NOT THE SAME as the original file.


----------



## chef8489

GrussGott said:


> Exactly, your DAC converted ERRORED data into analog sine waves WITH ERRORS (music) that is NOT THE SAME as the original file.


Holy crap I said that it was not the same original file and that was not what I was talking about. Christ. This is why people get so pissed off with you.


----------



## GrussGott

chef8489 said:


> Holy crap I said that it was not the same original file and that was not what I was talking about. Christ. This is why people get so pissed off with you.



could be, my apologies ... so then we agree that USB isochronous transfer mode errors could be prevented by higher-spec architected cables?

Thus leaving the only question as - can we hear those errors consistently enough to make that cable worth it?


----------



## sonitus mirus (Jul 22, 2018)

donunus said:


> chef8489, pictures load before viewing while music plays as it is streaming through the cable. There is no timing issue with a picture being viewed because it is preloaded.


Audio also ‘loads’ prior to playing, though it is possible to have errors with dropped frames.  These frames are rarely dropped and isochronous transfers have the highest priority.  We are talking about possibly 125 micro seconds of UAC audio data IF an error occurs.  I seriously doubt this error could be heard.  If a USB cable is designed and manufactured to specs, there should almost never be any isochronous data errors, and if there were errors, this is digital, and these errors would not just randomly occur in bunches that would be audible on a few select audio tracks.  Such a poor performing cable would be obviously and measurably defective.


----------



## donunus

well the doubting part if it can be heard can easily be debunked once you dive in to actual listening tests. But seriously though, I guess music can be loaded before playback but I don't think the DACs have big enough memory buffers to store entire tracks of music.


----------



## colonelkernel8

sonitus mirus said:


> A letter responding to folks on this site from USB.org.
> 
> http://thepenguin.eu/2018-01-19-audiophile-usb-cables/





sonitus mirus said:


> I'd like to see someone run a test with a generic 3 meter USB cable and see how many isochronous errors were found transferring test data at full capacity over USB 1.0 and 2.0.  I don't expect that there would be more than 1 error in a 24 hour period, if any at all.  If someone can show that errors are an issue, then we can discuss if the cable is the likely culprit.  Assuming that full USB transfer rates are typically significantly higher than practically every popular audio format and 3 meters is probably a much longer cable than most people use when connecting a DAC to a PC or phone/device, it is very unlikely that USB cables matter.


The issue with isosynchronous errors is they also don’t square with the descriptions people provide of what different USB cables sound like. A single word error (16 bit) in an audio stream would at its worst sound like a pop or a click or otherwise generally be undetectable after a low pass reconstruction filter. It’s really silly at this point.

To take it further, almost no high end home USB audio DACs are isosynchronous. They have buffers and error checking because the latency isn’t an issue with audio replay. With a studio USB audio interface, you need as little latency as possible, so they are isosynchronous. You’re misinformed @GrussGott.


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## colonelkernel8 (Jul 22, 2018)

donunus said:


> data is streamed through the cable in real time while the music is playing.
> EDIT: Nice try with the philosophical trolling though. Props for that lol


No it isn’t. Not with the majority of USB audio DACs. You and @GrussGott are now set on this false narrative of isosynchronous usage in USB DACs. It’s obvious you’re now cherry picking evidence to support this bias of yours.


----------



## donunus (Jul 22, 2018)

I am lost here so are you guys saying that any old dac can load a 200 megabyte dsf file, you can take off the usb cable and the thing will still play the music? I always understood that the computer is still sending the file to the dac as it is playing the music in real time.

EDIT: If the DAC stores the music before playback THEN I will agree that USB cables don't make a difference. Other than that it's either bad ears or bunk science.


----------



## colonelkernel8

donunus said:


> I am lost here so are you guys saying that any old dac can load a 200 megabyte dsf file, you can take off the usb cable and the thing will still play the music? I always understood that the computer is still sending the file to the dac as it is playing the music in real time.


No. It doesn’t need to. The process of resending a packet with an error in it takes microseconds. It only needs to buffer a few samples to correct an error packet before it’s sent to the DAC for conversion. Generally, popular devices like the XMOS USB audio interface transfer several samples per USB packet, and it will buffer several hundred samples at a time.


----------



## GrussGott (Jul 22, 2018)

colonelkernel8 said:


> No it isn’t. Not with the majority of USB audio DACs. You and @GrussGott are now set on this false narrative of isosynchronous usage in USB DACs. It’s obvious you’re now cherry picking evidence to support this bias of yours.



tonally I disagree, but mostly I agree with your point.

There are a ton of variables, and there are ton of different system configs that can, say, skip iso altogether ... so, yeah, I'm definitely cherry picking to focus on a simple path to USB cables having an impact.  (although I would argue that many here don't understand the basics of the USB spec, so there's that)

And, really, that complexity is why the topic never gets resolved in any global way, and never will.

AudioQuest and others make great money selling all kinds of cables including USB, and their industry and businesses are growing, so that's it's own kind of resolution.

Ultimately people have voted with their wallets, whatever the "truth" is


----------



## donunus

key words if it doesn't alll load into a device beforehand.... Timing errors


----------



## Arpiben

USB Audio is *Isochronous:*

Iso = Single in greek ( Plesio/several)
Packets are sent timed with one single rythm:the PC/DAP's *USB clock*
For Full Speed USB packets are sent every 125us with a maximum size of 1024 byte
The USB Audio *data transfer mode* between PC/DAP and DAC is _*Asynchronous*_ in most of cases:

DAC receives the packets and buffers them.
DAC controls its buffer size using its own clock not the recovered one from PC/DAP->asynchronous
When the buffer is almost full/empty DAC requests PC/DAP to decrease/increase the size of packets
DAC can not request a timing change or pause.
Clicks/pops occur when buffer can not absorb the packet bursts
Data Integrity in USB Audio:

In principle when a packet is detected erroneous (CRC) there is no request for resending it
Errors can eventually be corrected inside DAC/MCU chip.
Some DAC vendors pretend that when using their Windows drivers there is request for resending the bad packet ( I don't know).
USB cables, unless defective or out of specs are rarely the cause of bit errors.
PC/DAP internals (USB buses/PCB layout/etc) are more likely to generate errors vs cable
Some vendors are over exaggerating  the data integrity in order to sell their products: purifiers,cables,etc.
Unless design flaws or defective item the propability to have errors is extremely low.
Regarding a standard USB cable, you can send packet burst at USB Audio rate during months and you will not have any single error.


----------



## colonelkernel8

GrussGott said:


> Ultimately people have voted with their wallets, whatever the "truth" is



People also bought pet rocks. Voting with your wallet doesn't make something true, or good.


----------



## GrussGott (Jul 23, 2018)

Arpiben said:


> *USB cables*, unless defective or out of specs *are rarely the cause of bit errors.*
> PC/DAP internals (USB buses/PCB layout/etc) are *more likely* to generate errors vs cable
> Some vendors are over exaggerating  the data integrity in order to sell their products: purifiers,cables,etc



So for any given system (I'm only concerned with mine) the question would be what's "rarely" and "more likely"?

And, yes, some vendors move beyond exaggerating into outright lying.



colonelkernel8 said:


> People also bought pet rocks. *Voting with your wallet doesn't make something true, or good*.



Sure, yet we're now all agreed that it's technically possible for cables to matter, the question is what is the probability in any given system that there's an audible impact?

To "scientifically" know we could do all kinds of measurements on each of our setups ...

*or we could just try high-end USB cables for free as all reputable cable vendors all you do*.  And I think we're also agreed that that should probably be one of the last tweaks one should try with their system.


How did USB cables become controversial when we're all agreeing now?


----------



## bfreedma

GrussGott said:


> So for any given system (I'm only concerned with mine) the question would be what's "rarely" and "more likely"?
> 
> And, yes, some vendors move beyond exaggerating into outright lying.
> 
> ...




I'm not sure I'm on board with the plan.  Throw money at a problem the overwhelming majority don't have with a solution that wouldn't be likely to fix the problem for the few who really do experience the issue?

Do you have data that shows a level of data corruption on the USB connection/data topology in question representing an actual issue in any reasonable facsimile of the typical listening environment.  If that doesn't exist, why the concern?  Because it could be a theoretical issue based on, at best, an extremely rare use case?  In that unusual/unique scenario, better to diagnose the exception and then invest with a reasonable chance of impacting the problem for the better.


----------



## GrussGott (Jul 23, 2018)

bfreedma said:


> I'm not sure I'm on board with *the plan.  Throw money at a problem* the overwhelming majority don't have with a solution that wouldn't be likely to fix the problem for the few who really do experience the issue?



No, the plan is to not throw money at anything ... at least that's not my plan nor my recommendation.

My recommendation is if you're set for HPs, amps, DACs, etc, you can try high-end USB cables for FREE (<- no money) for 30 or 60 days.  We're all agreed that it's technically possible for one to hear an improvement, the open question is the probability.

Again, when it's free to try something, the probability becomes irrelevant and we move into nothing-ventured-nothing-gained territory ... at least for leisure hobbies like music enjoyment.

PS - Interesting that you asked me for data, but prior, threw around words like "overwhelming majority" - do you have data showing that's true?  Not that I care.


----------



## Phronesis

GrussGott said:


> No, the plan is to not throw money at anything ... at least that's not my plan nor my recommendation.
> 
> My recommendation is if you're set for HPs, amps, DACs, etc, *you can try high-end USB cables for FREE* (<- no money) for 30 or 60 days.  We're all agreed that it's technically possible for one to hear an improvement, the open question is the probability.
> 
> ...



The bigger challenge may be in how you go about "trying" the cables.  Casual sighted listening comparisons without controls are known to be unreliable, even when listeners are quite sure they're perceiving clear and obvious differences - I know because I've experienced this kind of misperception myself! (PM sent)


----------



## Arpiben

GrussGott said:


> So for any given system (I'm only concerned with mine) the question would be what's "rarely" and "more likely"?
> 
> And, yes, some vendors move beyond exaggerating into outright lying.
> 
> ...



You are free to try.
You are also free to keep in mind that USB cables are no the cure for:

DACs susceptibilty to ground noises (EMI/RFI/PSU/Internal from FPGA/MCU/etc)
PC/DAP issues
Users letting EMI/RFI appliances on top of their DACs: phones/PSU/etc


----------



## gregorio

So, you answered pretty much NONE of my questions and just responded with a bunch of information (which you apparently didn't understand) and asked me questions. Why should I answer your questions and you ignore mine, is it one rule for you and another for everyone else?

At least for the potential benefit of others, I won't be petty and I will respond:



GrussGott said:


> (A) No sir, you need to read the USB specs.
> It comes down to two things:
> (1.) If a square wave is impacted by EMI ...
> [1a] What happens if a transmitted voltage is altered by EMI in transit and thus mis-read on the receiving end? Is that impossible with all in-spec USB cables?
> ...



A. So he (sir) needs to read the USB specs but you don't? If you had read the specs then you would know:

1. The USB spec does NOT specify square waves, it specifies an "eye pattern" and the exact tolerances of the eye pattern. So why do you keep going on about square waves and impacts on square waves?
1a. Not impossible but not far off. USB specifies differential data signalling through a twisted pair (D+ and D-). In essence this is identical to a balanced type connection used in analogue audio. Any EM interference entering the cable will almost certainly affect both D+ and D- equally and will therefore be eliminated/rejected by the receiver (Common Mode Rejection, CMR). Under normal conditions, EMI entering the cable should never cause missed/altered bits, unless maybe if you live next door to an industrial magnet factory!

2. In the unlikely event there is a missed or corrupted bit and the receiver (DAC) has insufficient internal resources to apply it's own error correction, then clearly the DAC has been badly/incompetently designed!

3. And why is that important? With bulk transfer mode data is typically transmitted at the highest available transmission speed (EG. 480Mbps with USB 2), data loss is more likely and therefore packet resend error correction is important. Stereo CD for example runs at a tiny fraction of the highest available transmission speed (approx. 1.4Mbps) and within a guaranteed data bandwidth. So there's far less chance of an error in the first place and a packet resend facility is not important, CRC error detection and correction is sufficient.

"There can be errors" is *NOT* the same as "There are errors"! Which brings me back to a question I've asked and you have avoided: *What reliable evidence do you have for the actual existence of all these (supposed) errors?*



GrussGott said:


> [1] So why is isochronous-asynchronous - letting the DAC be the master clock - important?
> [2] As I understand it, Jitter. ...
> [2a] In other words, if any of these measurements don't arrive correctly or on time then you hear it ...



1. It's not necessarily important, only really to cover the *possibility* of an out of spec clock in the source/host USB controller (+ or - 500ppm). For example, a poor design which does not adequately account for crystal ageing.

2. Yes, jitter is the result. There will always be some amount of jitter, even with "in spec" host and receiver clocks in asynchronous mode.

2a. How do you get from "there *might* be errors" and "there will be jitter" to: "then you hear it"? Either you're just completely making up nonsense or post some reliable evidence to back up your claim! In practise, even cheap DACs reduce jitter errors/noise down to -120dB or so. For example, the Behringer UMC204HD reduces jitter noise to around -130dB, good luck trying to even reproduce that, let alone actually hear it! 



GrussGott said:


> (1.) If your DAC enumerates as USB Audio class it will select isochronous data transfer mode - live stream and no error correction
> (2) If you have have a decent DAC, it will select the asynchronous sub-mode which means the DAC controls the clock (this helps with jitter errors)
> (3.) Live transmission of, say, a 44/16 will begin, and there will be errors, and those errors won't be corrected for
> (4.) The DAC will live convert those errored bits into an analog sine wave
> (5.) You may hear the effect of those errors.



1. No, that is an *untrue* statement! Any competently designed DAC will indeed have error correction! It will have CRC to identify which bit is in error and then it will correct that bit. The only error correction methodology isochronous mode prohibits is packet resend.

2. Define "decent DAC". The above Behringer unit, with jitter down at -130dB (and is therefore at least "decent"), costs about $80 inc. Shipping.

3. Again, there CAN be errors does NOT mean there WILL be errors. Presumably you can present some reliable evidence to back up your claim that there WILL be errors? And yes, if there are errors they WILL be corrected by any competently designed DAC. The only exception would be where the number of consecutive errors exceeds the tolerance of the DAC's error correction mechanisms and then the result would be as already mentioned by others, a digital glitch (an obvious pop/click).

4. No, the DAC will convert those error corrected bits into an analogue signal.

5. What effect and what errors?

Much of the above (your points or my responses) has little/nothing to do with USB cables! Step 1: Even if we were to assume that there are uncorrected and audible errors with a standard USB spec cable, what reliable evidence can you present to back up your claim that those errors would be eliminated by an expensive audiophile cable?

G


----------



## colonelkernel8 (Jul 23, 2018)

GrussGott said:


> So for any given system (I'm only concerned with mine) the question would be what's "rarely" and "more likely"?
> 
> And, yes, some vendors move beyond exaggerating into outright lying.
> 
> ...


Are you now holding water for high-end cable manufacturers? They perpetrate fraud on a daily basis, I don’t want to give them business. You don’t get to make fact-free claims first to color a person’s perspective and then wait for the confirmation bias to roll in (the cable makers that is, not you).


----------



## Arpiben

Phronesis said:


> The bigger challenge may be in how you go about "trying" the cables.  Casual sighted listening comparisons without controls are known to be unreliable, even when listeners are quite sure they're perceiving clear and obvious differences - I know because I've experienced this kind of misperception myself! (PM sent)



Well since @GrussGott has good friends an alternative would be to let them test his USB cable with Data tester more or less similar to:


----------



## bfreedma

GrussGott said:


> No, the plan is to not throw money at anything ... at least that's not my plan nor my recommendation.
> 
> My recommendation is if you're set for HPs, amps, DACs, etc, you can try high-end USB cables for FREE (<- no money) for 30 or 60 days.  We're all agreed that it's technically possible for one to hear an improvement, the open question is the probability.
> 
> ...




Nice deflection on the request to support the claim that USB audio transmission is an actual issue in a realistic real world scenario.  Answering a question with a question has a definite connotation in a debate...

You're also abusing the system if you continuously try cables or other solutions for "free".  Ignoring that all of our time has value, the try and return model drives up vendor cost and in the end, they raise prices to address it.  Unless you're on board that either the profit margin in cables is so great that the vendors don't actually suffer materially if a large percentage is returned, or that cable vendors repackage used cables as new.

I don't know with absolute certainty that putting a large inflatable pig in my listening room will improve headphone SQ, but until someone provides reasonable evidence, I think I'll hold on to my money.


----------



## bigshot (Jul 23, 2018)

I think this guy really loves the attention he's generating. I wonder if he even owns any audio equipment. If he does, he's "voting with his wallet" in a way that would make P. T. Barnum proud.


----------



## bigshot

donunus said:


> If the DAC stores the music before playback THEN I will agree that USB cables don't make a difference



Buffering?


----------



## sonitus mirus

GrussGott said:


> Sure, yet we're now all agreed that it's technically possible for cables to matter, *the question is what is the probability in any given system that there's an audible impact?*



How is this not blatantly obvious at this point in the discussion that the answer to that question is practically no impact at all outside of some pathological situation that probably should be addressed properly first before using cables in any attempt to remedy?  A certified USB cable connecting certified USB devices should not make any difference, and any audible differences from a malfunction would translate to pops, clicks, static, or no sound at all.



GrussGott said:


> How did USB cables become controversial when we're all agreeing now?


  The controversy is with how some people seem to unquestioningly believe that USB cables can alter subtle sound characteristics that can easily be heard.  That seems extremely unlikely based on the information provided by both sides of the discussion.  It would largely be a fools errand to use various USB cables in an attempt to tweak the overall sound quality.


----------



## Phronesis

bigshot said:


> I think this guy really loves the attention he's generating. I wonder if he even owns any audio equipment. If he does, he's "voting with his wallet" in a way that would make P. T. Barnum proud.



Let's not make it personal.  I take him to be sincere in the views he expresses, which are directly relevant to the thread topic.  Just because someone says things that deviate from the mainstream view of people posting in a thread, that doesn't make it trolling.  And if anyone doesn't want to engage with him, they have to choice to not do so - we all participate in discussions voluntarily, and the stakes involved in this topic are rather small, so let's not pretend that anyone is here out of obligation to protect the world against dangerous untruths.


----------



## bigshot (Jul 23, 2018)

I don't care if he spouts bologna. There's a whole world full of that outside sound science. My objection is that he isn't discussing with us. He's talking *at* us and not responding to any points that don't go his way. He's also being disrespectful as an argumentative technique. To me, those things are disingenuous. You can grant him respect if you'd like, but with me he has to earn it. I'm always polite first. Then I hear how they represent themselves and I judge by the integrity of what they say. I reserve that right.


----------



## sonitus mirus

Arpiben said:


> Well since @GrussGott has good friends an alternative would be to let them test his USB cable with Data tester more or less similar to:



I wonder if UAC2 could transmit error-free for 10 straight days?  Supposedly that is what was seeing errors that was the root of all this controversy.  Though, it was never established that any cable could reduce the number of errors.


----------



## Phronesis

bigshot said:


> He isn't discussing with us. He's talking at us and not responding to any points that don't go his way. You can grant him respect if you'd like, but with me he has to earn it.



That's how debates go sometimes.  If you don't like how someone is debating, just stop debating with them.  I don't see it as a matter of respect or lack of respect, just basic courtesy and not making things personal.


----------



## sonitus mirus

bfreedma said:


> I don't know with absolute certainty that putting a large inflatable pig in my listening room will improve headphone SQ, but until someone provides reasonable evidence, I think I'll hold on to my money.



I can't answer with regards to your listening room, but it sure did seem to make for a more entertaining Pink Floyd concert.


----------



## donunus

bigshot said:


> Buffering?


The computer buffers data but thats before the USB cable stage isn't it?


----------



## bfreedma

sonitus mirus said:


> I can't answer with regards to your listening room, but it sure did seem to make for a more entertaining Pink Floyd concert.




LOL - I'll have to listen to Animals later today.

Can you produce your ABX of a PF concert with and without the inflatable pig?  Were the, um, "conditions" the same at both concerts?


----------



## bigshot (Jul 23, 2018)

The only problems I've heard about with USB cables not performing to spec involved the charging pin. There are certain devices that can't charge with certain USB type C cables. It doesn't affect data transfer that I know of.



donunus said:


> The computer buffers data but thats before the USB cable stage isn't it?



The buffer goes on the other end of the cable... in the DAC. Most modern DACs include buffers so the stream going through the DAC is solid. The latency is so small you can't hear it because the buffer fills up much quicker than the music plays. The buffer is constantly refilling and trickling out the signal to the DAC with perfect timing.

I really like the Sonic Swine! He would go good with my Sonic Swordfish!


----------



## castleofargh

donunus said:


> The computer buffers data but thats before the USB cable stage isn't it?


of course the DAC has a buffer. the way you imagine USB streaming would define it as analogue, and we should all be pretty clear on the fact that it isn't. the data is sent in packets, the size of those packets doesn't even has to correspond to a full audio sample or a fixed number of full audio samples. because it doesn't matter how the data is "cut", those packet will be put back together to form whatever code, containing the audio sample values, some communication codes, and whatever else defined in the USB protocol standard. any modern DAC will resync the data to it's own clock, so it should be obvious that buffering is involved otherwise how could it be done?


----------



## bigshot (Jul 23, 2018)

The only way a USB cable could fail to play sound properly that I can think of is to block enough packets that the buffer runs out. That would require a huge failure. I can also imagine some sort of RF interference getting into the DAC though cables, but that would be a whole lot of interference or a DAC that isn’t designed very well. I don’t see any way that subtle differences could be caused. If people report nebulous stuff like narrow soundstage or veils, I would more likely suspect bias or sloppy comparison.


----------



## Phronesis (Jul 23, 2018)

bigshot said:


> The only way a USB cable could fail to play sound properly that I can think of is to block enough packets that the buffer runs out. That would require a huge failure. I can also imagine some sort of RF interference getting into the DAC though cables, but that would be a whole lot of interference or a DAC that isn’t designed very well. I don’t see any way that subtle differences could be caused. *If people report nebulous stuff like narrow soundstage* or veils, I would more likely suspect bias or sloppy comparison.



My sense is that claims of being able to hear better soundstage are more a matter of active perception than the gear, especially with headphones.  If the 3D structure of the outer ear isn't being used in a normal way to localize sound in space (which isn't possible with headphones), soundstage is already very compromised, then add in the facts that the perception of soundstage also very much depends on the recording, plus most recordings are mixed for speakers rather than headphones.  I've heard variations in the sense of how 'big' the soundstage is with headphones (largely influenced by frequency response), but have never heard a headphone that I thought had an overall 'good' sense of soundstage.


----------



## GrussGott

Arpiben said:


> You are free to try.
> You are also free to keep in mind that USB cables are no the cure for:
> 
> DACs susceptibilty to ground noises (EMI/RFI/PSU/Internal from FPGA/MCU/etc)
> ...



Totally, there's a whole hullaballoo on the Schiit Jot thread about "building amps with ground loops" that's got Jason involved


----------



## bigshot

Phronesis said:


> My sense is that claims of being able to hear better soundstage are more a matter of active perception than the gear, especially with headphones.  If the 3D structure of the outer ear isn't being used in a normal way to localize sound in space (which isn't possible with headphones), soundstage is already very compromised, then add in the facts that the perception of soundstage also very much depends on the recording, plus most recordings are mixed for speakers rather than headphones.  I've heard variations in the sense of how 'big' the soundstage is with headphones (largely influenced by frequency response), but have never heard a headphone that I thought had an overall 'good' sense of soundstage.



agreed on every point


----------



## GrussGott (Jul 23, 2018)

gregorio said:


> So, you answered pretty much NONE of my questions


That's because I only respond to stuff I find interesting or useful and because I don't exist to serve you ... unlike most of the other posters here, I guess


gregorio said:


> *1. No, that is an untrue statement! *Any competently designed DAC will indeed have error correction! It will have CRC to identify which bit is in error and then it will correct that bit. *The only error correction methodology isochronous mode prohibits is packet resend*.



My lord you're dramatic ... yes USB isochronous transfer mode CALCULATES for errors, but as you said it does not request more data, the DAC has to just deal with it.  See?  we can agree about stuff and it's all cool.

Might want to switch to decaf.


----------



## GrussGott (Jul 23, 2018)

colonelkernel8 said:


> Are you now holding water for high-end cable manufacturers? They perpetrate fraud on a daily basis, I don’t want to give them business. You don’t get to make fact-free claims first to color a person’s perspective and then wait for the confirmation bias to roll in (the cable makers that is, not you).



Just holding water for truth and accuracy!  And the truth is USB cables amongst a zillion other things can affect sound quality due to transmission errors.   (<- chock full o' facts!)

What you do about that ... try them, buy them, don't buy them, up to you.  I don't care.


----------



## GrussGott (Jul 23, 2018)

sonitus mirus said:


> The controversy is with how some people seem to unquestioningly believe that USB cables can alter subtle sound characteristics that can easily be heard.  That seems extremely unlikely based on the information provided by both sides of the discussion.  It would largely be a fools errand to use various USB cables in an attempt to tweak the overall sound quality.



Nobody should "unquestionly" believe anything so, yeah, with you there.   That would be religious.  BTW, this isn't the religious forum right?


----------



## GrussGott (Jul 23, 2018)

bigshot said:


> He's also being disrespectful as an argumentative technique.








    dude.  If we edited all of your posts for name-calling, personal attacks, and bullying there'd only be filler words left.

I could reply in kind, but I don't, because I don't care about you.


----------



## Phronesis

GrussGott said:


> dude.  If we edited all of your posts for name-calling, personal attacks, and bullying there'd only be filler words left.



Yes, I understand that people can get heated up, but there should minimal latitude for making things personal (personal attacks).  Debate the topic, not the person.


----------



## bigshot (Jul 23, 2018)

I'm not heated up. I just don't feel the need to waste my time and words on someone who doesn't back up their arguments, ignores other peoples rebuttals and just moves on without reply or admission, and assumes a tone that is disrespectful of the people he is talking with.

See the description under number 2 on this webpage:

https://www.wikihow.com/Win-Informal-Arguments-and-Debates


----------



## gregorio

GrussGott said:


> [1] That's because I only respond to stuff I find interesting or useful ... [1a] and because I doesn't exist to serve you
> [2] Yes it USB isochronous transfer mode CALCULATES for errors, but it does not request more data, the DAC has to just deal with it.
> [3] Just holding water for truth and accuracy! And the truth is USB cables amongst a zillion other things can affect sound quality due to transmission errors.
> [4] Nobody should "unquestionly" believe anything ...  [4a] this isn't the religious forum right?



1. So you just decide that anything which demonstrates you're talking rubbish or requires you to provide evidence to support your claims is not "interesting or useful" and you don't respond to it. Great, you can just carry on making up nonsense and talking rubbish and completely ignore the facts. Your refusal to respond to legitimate requests for supporting reliable evidence in this forum is, in effect, a tacit admission that you're lying, trolling or at least just making up nonsense!
1a. But this forum does exist to serve you? 

2. Yes, the DAC does have to "just deal with it" but it deals with it by employing it's own internal error correction, it does NOT as you state, "deal with it" by just reconstructing an incorrect analogue waveform with the erroneous bit (uncorrected)!

3. Supporting evidence or you're lying, trolling or making up nonsense! And, how would you have any idea what "the truth is" if you don't find the truth "interesting or useful" and ignore it? You can't have it both ways, unless of course you're a hypocrite and a troll.

4. But making up nonsense and ignoring the facts is perfectly OK? 
4a. Not unless you're successful in your attempts to pervert it!

G


----------



## Phronesis

bigshot said:


> I'm not heated up. I just don't feel the need to waste my time and words on someone who doesn't back up their arguments, ignores other peoples rebuttals and just moves on without reply or admission, and assumes a tone that is disrespectful of the people he is talking with.
> 
> See the description under number 2 on this webpage:
> 
> https://www.wikihow.com/Win-Informal-Arguments-and-Debates





bigshot said:


> I think this guy really loves the attention he's generating. I wonder if he even owns any audio equipment. If he does, he's "voting with his wallet" in a way that would make P. T. Barnum proud.



Then why write the above?  It's clearly a personal attack to suggest that someone is seeking attention, may be lying about the gear he owns, and is a sucker with regard to being duped into spending money.  It has nothing to do with whether USB cables can affect sound.


----------



## bigshot (Jul 23, 2018)

Because I think the reason he isn't debating fairly is because he's trolling. Trolls say things that they think will get a rise out of a group deliberately to attract attention to themselves. It's a time honored internet forum tradition. He may not even have any particular interest in USB cables. I've been on the internet since the days of usenet, before there were such things as web forums. I've seen this kind of behavior before. It fits the pattern. He isn't discussing, he's doing a monologue and we are supposed to be his pawns. I'm opting out and calling it, that's all. You can feel free to answer him if you want. And I'm happy to chat with you. No problem there. I'm just letting you know why I am responding like I am.

This forum regularly gets invaded by people who come here for the express purpose of rattling our cage. The subject here is science. We talk about things analytically and we apply science. People who come in here saying "Science doesn't know everything, so it can't know anything" aren't here to discuss science with us. They're here to crap on the purpose of this forum. I kinda like it here. I don't need or appreciate people like that. They have the whole rest of Head-Fi to do that in.


----------



## sonitus mirus

An older blog post from Archimago has more information about USB cables and even provides audio samples of a properly working USB cable vs an improperly working USB cable. 

http://archimago.blogspot.com/2014/01/demo-measurements-what-does-bad-usb-or.html

Interesting to note that the letter from USB.org that was linked to earlier dismisses jitter as a USB cable issue.

_"Jitter is not a cable problem. Jitter is a transceiver (PHY) issue on the devices."
_
This is further supported with Archimago's jitter testing between the good and bad USB cables, revealing practically no legitimate difference being measured.

_"In any case, using a different DAC, the jitter test remains unchanged; two examples now of how an obviously poor USB cable does not appear to affect the jitter from asynchronous DACs in terms of the analogue output (which IMO is the only important measure since that's what we hear!)."_


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## GrussGott (Jul 23, 2018)

bigshot said:


> Because I think the reason he isn't *debating fairly *


@castleofargh , as moderator, do thread/sub-forum rules dictate we have to address any and every question, topic, or inquiry posed?



gregorio said:


> requires you to provide evidence ... Supporting evidence *or you're lying ...Your refusal to respond to legitimate requests ... *



Greg, given you're in the entertainment industry, maybe you have a lot at stake in these threads, I'm not sure.

For me, this is an informal leisure hobby forum; my responses are meant as a general contribution to the thread in a public "here's a thought..." style, saving PMs for 1-to-1 comms.

I'm flattered you want all my responses to every point, thanks for that, however my recommendation is we create a group base of knowledge where everyone contributes versus logging 1-to-1 banter.

You made some great points.


----------



## bigshot (Jul 23, 2018)

Great info Sonitus Mirus. I've never found an example of jitter coming anywhere close to audible levels. I think jitter is a theoretical hoodoo. The example of the "bad USB" cable sounded exactly how I would expect it to... pops and dropouts that aren't subtle.


----------



## GrussGott (Jul 23, 2018)

sonitus mirus said:


> An older blog post from Archimago has more information about USB cables and even provides audio samples of a properly working USB cable vs an improperly working USB cable.



If you'd like measurement data across a range of interfaces (USB, SPDIF, TOS, etc) and products you can't beat atomicbob's stuff.  This is purely a place to start, you have to go farther afield with a google search to get the benefit of his knowledge which is not directed at USB specifically, more at products and product chains in general, covering USB along the way.  USB cable shield resistance technical measurements could be something to google for tangential info and measurements, or system synergy special sound.  Bob's super-synergy systems don't usually have spendy USB cables, but rather cables he's found to be of reliable quality.

And as long as we're posting jitter, might as well have NWAVGUY's link handy


----------



## bigshot (Jul 23, 2018)

"I don't believe jitter is an audible problem in reasonably well designed products." -NWAVGUY

I can up the ante on that a bit. I've been looking for several years for any consumer audio product with audible levels of jitter. The closest I have been able to find is a McIntosh media server that a knowledgeable Sound Science participant pointed out to me. It had a remarkably high level of jitter, but it was still well below the threshold of audibility. Most consumer audio components- even very cheap ones- have jitter levels more than an order of magnitude below audibility. If anyone knows of any consumer audio products with audible levels of jitter, please let me know.

We can measure far further than we can hear. Most audiophools know a lot about measurements and they can recite technical sales pitch they memorized from manufacturer's tear sheets, but they make very little effort to determine where the threshold of audibility lies for various types of timing errors, imbalances, noise and distortion. It took me about a week of googling part time to figure it all out. Now I know that most of the mountains people talk about on Head-Fi aren't even molehills. They're a tiny individual grain of sand on the beach.

Perspective is sadly lacking in the home audio community. Happily, there is a solution... the line level matched, direct A/B switchable double blind test. That is the tool for us to put measurements into context.


----------



## castleofargh

GrussGott said:


> @castleofargh , as moderator, do thread/sub-forum rules dictate we have to address any and every question, topic, or inquiry posed?


but of course. under law as decreed by Aslan the lion or Narnia, answering is mandatory and I'm always here to make sure you answer.




seriously though, you've been working real hard as a fisherman to get whatever might suggest some remote possibilities of errors occurring somewhere in USB streaming. but to what end?
you haven't been concerned about statistical occurrence or magnitudes of any of the stuff you've brought up. in most posts you "forgot" to show how the USB cable is the cause or the solution for it. or what difference in the special cable would lead to that result. also nothing about any of all that leading to evidence of audibility. so where are you trying to go exactly?
you haven't bothered trying to confirm that your entire belief on this subject isn't due to placebo and bad testing method. 
all in all, it's not pretty and even people believing that fancy USB cables are important, might have a hard time standing behind you.  
I believe that crap happens and that it's fairly possible to have some audible impact due to weirdo USB cable and other massive issues sometimes. I think it's rare and I don't think it has much of anything to do with decoding the proper binary code. but still I believe in the possibility, given the right circumstances. 
and yet I'm clearly against most of your posts. 

do you even have an idea about what a "better" USB audio cable should have as electrical specs? or is your grand solution only to get a bunch of cables and keep the one our guts tell us to keep in a sighted test? is that how we determine fidelity now? 
you go back and forth from trying to convince people about all the binary errors in USB, to "let your soul, be your pilot". it's a contradiction on top of everything else.


----------



## GrussGott (Jul 23, 2018)

castleofargh said:


> *even people believing* that fancy USB cables are important, *might have a hard time standing behind you*.



That's fair and I wouldn't ask anyone to "stand behind me" since I'm a digital signals processing amateur: I didn't design the USB interface and I don't design products using it, so I wouldn't feel ethical offering an absolutist opinion on USB cables.

What I can do is share my USB cables experience and offer an opinion on technically why.

Plus, I've been married for a few decades so i can use the alone time.


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## bigshot (Jul 24, 2018)

Anybody is qualified to put forward anecdotal information. There are people out there who will offer all sorts of opinions. You know the old saying that goes along those lines. I don't have to repeat it. However, "offering an opinion on technically why" requires experience, solid research and honest critical thinking. Gregorio was doing that and you told him he wasn't qualified. You were dead wrong there. You had an opportunity to learn something and improve your knowledge and you blew it.

The point of a discussion isn't to win at all costs and never back down. And it isn't to dominate the conversation and puff yourself up. The point is to learn from each other and discover the truth together. I think you've got a lot to learn.


----------



## jagwap

Everyone is having fun I see.

One or two points I can add, of help I hope:

USB audio does not have error correction as has been stated. It has error detection. But then the DAC cannot correct for these errors. Not in the way people think as in CD reed-solomon error correction, where the error is perfectly repaired through redundancy stored data in thr stream. A pity, but thats the way it is.  At best you may be able to interpolate the error out. However, as any USB cable within the USB specification has less than one error a month when transmitting for a month, this is not worth worrying about.

As to jitter, asynchronous is the way to go. If not a PLL is needed. Any DAC always needs one anyway for the other inputs, so it can be argued is is no disadvantage. But clocking a DAC from a nearby fixed clock of known quality while the USB as asked to supply the data at the rate required is just the right way to do it. Relying on a PC clock to dictate the data rate is less elegant when you don't have to.

But as to cables making a difference? Maybe, but:

Not because of jitter as asynchronous USB doesn't have any.

Not because of errors, as there aren't any.

So what is left? RF interference and ground loops.

So get a galvanicaly isolated USB adaptor and stop worrying, and also save money on pretty cables.

Now have ypu seen these gold plated TOSLINK cables?

https://www.amazon.com/Cable-Matters-Toslink-Digital-Connectors/dp/B0099UWHH6


----------



## Arpiben

jagwap said:


> Everyone is having fun I see.
> 
> One or two points I can add, of help I hope:
> 
> ...



Unfortunately too many of those are in the market.
In industry fibers connectors are less shiny:


----------



## gregorio

GrussGott said:


> [1] Greg, given you're in the entertainment industry, maybe you have a lot at stake in these threads, I'm not sure.
> [2] For me, this is an informal leisure hobby forum; [2a] my responses are meant as a general contribution to the thread in a public "here's a thought..." style ...
> [3] ... my recommendation is we create a group base of knowledge ...
> [4] I wouldn't feel ethical offering an absolutist opinion on USB cables.
> [5] What I can do is share my USB cables experience and offer an opinion on technically why.



1. Nope, it makes no difference to me professionally.

2. That's my point, this forum isn't "for you" and neither is this the "informal leisure hobby" forum, it's the Sound Science forum. We are less formal than the world of published science, nevertheless, science and the actual facts are the ultimate priority here, not least because it's so actively discouraged in the other sub-forums.
2a. But that is NOT how you've presented your contributions. You have not said "it's my thought that ..." or posted statements with any sort of conditionality, your "style" has been absolute; "there will be errors, those errors will not be corrected", "the truth is ...", "I know what I hear", etc. And AGAIN, this is not the "Here's a Thought" forum, it's the Sound Science forum!

3. A "group base of knowledge" based on what? Based on audiophile myths, marketing BS, uninformed/erroneous fan boy opinion/assumption or based on the actual facts and science?

4. But you've offered an inferred absolutist opinion on USB cables and offered absolutist opinions on a wide range of USB properties and digital audio data in general, all of which you appear to "feel" entirely "ethical" about? Even to the point of questioning the ethics of those who refute your "absolutist opinions"!

5. This isn't the "Share my Experience" forum or the "Offer my opinion Why" forum,  this is the Sound Science forum! Sharing one's experiences or opinions "on technically why" is not unacceptable here, what is UNACCEPTABLE is the repeated promotion of absolute opinions/statements which contradict the known facts/science and a refusal to provide any supporting reliable evidence!

ALL the points 2-5 above bring us back full circle to where we started. This is NOT the "informal leisure hobby" forum, the "what Grussgott finds plausible" forum, the "here's a thought" forum or the "promote any nonsense you want to make up or repeat" forum, this is the Sound Science forum and you are in the WRONG forum! This is the only forum on head-fi where the actual facts/science are given absolute priority/authority. We have a low tolerance for anyone attempting to pervert that absolute priority/authority and turn Sound Science into yet another forum where the absolute priority/authority is given to fan boys and marketing BS!

G


----------



## Phronesis

jagwap said:


> Now have ypu seen these gold plated TOSLINK cables?
> 
> https://www.amazon.com/Cable-Matters-Toslink-Digital-Connectors/dp/B0099UWHH6



Those are some nice looking cables!  Seriously, for a few bucks more, I'd buy them for the luxury aesthetics and potential placebo effect, even if my analytical/skeptical mind tells me there should be no difference in sound.


----------



## gregorio (Jul 24, 2018)

jagwap said:


> [1] USB audio does not have error correction as has been stated. It has error detection. But then the DAC cannot correct for these errors. ... At best you may be able to interpolate the error out.
> [2] But clocking a DAC from a nearby fixed clock of known quality while the USB as asked to supply the data at the rate required is just the right way to do it.
> [3] So what is left? RF interference and ground loops.



1. Aren't the last two sentences in this quoted point contradictory? If the DAC "interpolates the error out" hasn't the DAC "corrected for these errors"?
2. Are you suggesting that using an external master clock, rather than the DAC's own internal clock, is the "right way to go"?
3. How would a cable achieve USB specification if it had a ground loop and, any reasonable amount of RF interference would be rejected (CMR) by the differential signalling. So, what IS left? Abnormal/Extreme amounts of RF interference or, err, mmmm!

G


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## GrussGott (Jul 24, 2018)

gregorio said:


> We are less formal than the world of published science
> This is NOT the "informal leisure hobby" forum



Sounds a bit contradictory, Greg.  Readers and posters should consider that the URL is "head-fi.org" and that no poster (<- don't forget the 't' !) here is a digital signals processing scientist.

Further, relative to this thread, the USB spec is what it is, and the spec for the USB Audio Class says that DACs cannot re-request errored data and thus must deal with those errors on their own.   That means if any of us have a DAC like, say, the Mimby, well, it uses USB Audio Class 2 ... So, can the DAC recover from all errors perfectly and, if not, is that audible?

I've posted that one can use google to find atomicbob's very sciencey and specific testing of USB cable shielding (USB cable shield resistance technical measurements), including with popular brands (like AudioQuest and PYST).  What he finds in his non-leisurely testing is that generic cables like monoprice perform horribly and others, like the AQ Carbon perform great.

Thus, if you agree with Bob's testing methodology, from a scientific perspective, AQ cables are less likely to have their transmission effected.  Further, the Mimby is great, but its USB implementation (C-Media CM6631A) is, like all computer equipment, resource limited, including in its ability to deal with transmission-induced errors that Bob showed us happen.

Finally it's also a scientific fact that we can't define what's "correct" about re-produced audio - we just don't know about the biology to say that what was re-produced was exactly what was sent.  That's just the state of the science today.

QED.


----------



## jagwap (Jul 24, 2018)

gregorio said:


> 1. Aren't the last two sentences in this quoted point contradictory? If the DAC "interpolates the error out" hasn't the DAC "corrected for these errors"?
> 2. Are you suggesting that using an external master clock, rather than the DAC's own internal clock, is the "right way to go"?
> 3. How would a cable achieve USB specification if it had a ground loop and, any reasonable amount of RF interference would be rejected (CMR) by the differential signalling. So, what IS left? Abnormal/Extreme amounts of RF interference or, err, mmmm!
> 
> G



1. No. And you know it.
2. A DAC IC never has an internal clock. If you meant the clock in the "DAC box" then yes, the internal clock.
3. Ground loops exist between equipment, and you know that. The USB recieer PHY may reject RF to get the bit corrent, but the RF is now inside the DAC, and with all the FCC and CE approval out there, many designs are susceptable to some RF. PCs have a metric f*ck-tonne of RF flapping about.

Edited to remove interpretation. There still will be some, but I am aiming for a reduction.


----------



## sonitus mirus

Phronesis said:


> Those are some nice looking cables!  Seriously, for a few bucks more, I'd buy them for the luxury aesthetics and potential placebo effect, even if my analytical/skeptical mind tells me there should be no difference in sound.



Those are even cheaper than the ones I bought.  It was mostly an aesthetic decision and not performance related.

https://www.amazon.com/gp/product/B071KWFK87


----------



## GrussGott

Phronesis said:


> Those are some nice looking cables!  Seriously, for a few bucks more, I'd buy them for the luxury aesthetics and potential placebo effect, even if my analytical/skeptical mind tells me there should be no difference in sound.



Ha, I like my AQ interconnects and got the Atmos OFC copper cable for my ZMF Dynamics just cause I like the audio-jewelry look.  I've got a few more months of listening and testing before I'd be ready to say whether there's a difference from the stock cable, but it sure looks cool


----------



## bigshot (Jul 24, 2018)

There was a high end cable being touted here a few years ago that ended up being aquarium tubing stuffed with peat moss with two mono price wires running down the middle. The connectors looked like something out of a Frankenstein movie. It had fantastic anecdotal reviews!

Some folks are more subject to the effects of pretty equipment than others. My system is hidden away and the only thing out where you can see it is the remote control. I've always hated the look of black glowing boxes. I think I got that from my brother. He bought a full McIntosh system and then put it in a closet in the hallway outside the room.


----------



## Phronesis

Phronesis said:


> Those are some nice looking cables!  Seriously, for a few bucks more, I'd buy them for the luxury aesthetics and potential placebo effect, even if my analytical/skeptical mind tells me there should be no difference in sound.



Taking it further, placebo effects may occur despite our knowing it's a placebo: https://www.vox.com/science-and-health/2017/6/1/15711814/open-label-placebo-kaptchuk

My experience suggests to me that this kind of thing can happen with audio too.


----------



## bigshot

Phronesis said:


> Taking it further, placebo effects may occur despite our knowing it's a placebo



Yeah. You can't will bias away. The only way to minimize it is to put on controls... specifically blind testing. However if you're buying something for purely cosmetic reasons and you don't care about functionality, that's just preference, not bias.


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## GrussGott (Jul 24, 2018)

Phronesis said:


> Taking it further, placebo effects may occur despite our knowing it's a placebo: https://www.vox.com/science-and-health/2017/6/1/15711814/open-label-placebo-kaptchuk
> 
> My experience suggests to me that this kind of thing can happen with audio too.



That dude is pretty famous in medical circles and I like his description from another publication:

_"*The placebo effect is* *more than positive thinking *— believing a treatment or procedure will work. *It's* *about creating a stronger connection between the brain and body and how they work together,*" says Professor Ted Kaptchuk of Harvard-affiliated Beth Israel Deaconess Medical Center, whose research focuses on the placebo effect.

Placebos won't lower your cholesterol or shrink a tumor. *Instead, they work on symptoms modulated by the brain, like the perception of pain*. "Placebos may make you feel better, but they will not cure you," says Kaptchuk. "They have been shown to be most effective for conditions like pain management, stress-related insomnia, and cancer treatment side effects like fatigue and nausea."_​
And since hearing is similar to pain - modulated by the brain - and since we don't understand how the human brain "hears" or what "should be heard"  .... is the concept of placebo even applicable in listening to music?


----------



## bigshot

Placebo is just one form of bias. We're talking about bias in general, not just placebo.


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## GrussGott (Jul 24, 2018)

bigshot said:


> Placebo is just one form of bias. We're talking about bias in general, not just placebo.



What's the biological or neurological or psychoacoustical definition of bias?


----------



## bigshot

A simple google search provided me with this definition...

A cognitive bias is a systematic error in thinking that affects the decisions and judgments that people make. Some of these biases are related to memory. The way you remember an event may be biased for a number of reasons and that in turn can lead to biased thinking and decision-making. Other cognitive biases might be related to problems with attention. Since attention is a limited resource, people have to be selective about what they pay attention to in the world around them. Because of this, subtle biases can creep in and influence the way you see and think about the world.

Cognitive biases can be caused by a number of different things, but it is these mental shortcuts, known as heuristics, that often play a major contributing role. While they can often be surprisingly accurate, they can also lead to errors in thinking. Social pressures, individual motivations, emotions, and limits on the mind's ability to process information can also contribute to these biases.

Types of bias:

Confirmation Bias: This is favoring information that conforms to your existing beliefs and discounting evidence that does not conform.
Availability Heuristic: This is placing greater value on information that comes to your mind quickly. You give greater credence to this information and tend to overestimate the probability and likelihood of similar things happening in the future.
Halo Effect: Your overall impression of a person influences how you feel and think about his or her character. This especially applies to physical attractiveness influencing how you rate their other qualities.
Self-Serving Bias: This is the tendency to blame external forces when bad things happen and give yourself credit when good things happen. When you win a poker hand it is due to your skill at reading the other players and knowing the odds, while when you lose it is due to getting dealt a poor hand.
Attentional Bias: This is the tendency to pay attention to some things while simultaneously ignoring others. When making a decision on which car to buy, you may pay attention to the look and feel of the exterior and interior, but ignore the safety record and gas mileage.

Actor-Observer Bias: This is the tendency to attribute your own actions to external causes while attributing other people's behaviors to internal causes. You attribute your high cholesterol level to genetics while you consider others to have a high level due to poor diet and lack of exercise.
Functional Fixedness: This is the tendency to see objects as only working in a particular way. If you don't have a hammer, you never consider that a big wrench can also be used to drive a nail into the wall. You may think you don't need thumbtacks because you have no corkboard on which to tack things, but not consider their other uses. This could extend to people's functions, such as not realizing a personal assistant has skills to be in a leadership role.
Anchoring Bias: This is the tendency to rely too heavily on the very first piece of information you learn. If you learn the average price for a car is a certain value, you will think any amount below that is a good deal, perhaps not searching for better deals. You can use this bias to set the expectations of others by putting the first information on the table for consideration.

Misinformation Effect: This is the tendency for post-event information to interfere with the memory of the original event. It is easy to have your memory influenced by what you hear about the event from others. Knowledge of this effect has led to a mistrust of eyewitness information.
False Consensus Effect: This is the tendency to overestimate how much other people agree with you.
Optimism Bias: This bias leads you to believe that you are less likely to suffer from misfortune and more likely to attain success than your peers.
More info: https://www.verywellmind.com/what-is-a-cognitive-bias-2794963


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## GrussGott (Jul 24, 2018)

bigshot said:


> A simple google search provided me with this definition...



I guess I was asking specific to human hearing - like for music and stuff.

For those not aware, there's a field of research called psychoacoustics which basically integrates objective and subjective analysis to determine sound quality or lack thereof.  It's obviously used in audiology, but also for industrial and commercial studies for things like factory noise, airplane noise, venue ambiance, product design, etc.

Human hearing is not well measured past a certain level of complexity.  We can use frequency sweeps and like to identify gross capabilities, but when move to something complex like an outdoor scene or music, findings fall apart fast ... but strange correlations also appear.  For example women might be better able to place a child crying a park scene than men, but men are better at placing the barking german shepard.

But then if that women is more concerned about the crying child than the man, is that bias?  Or just capability?

The point is, there can bias for equipment, bias for a sound flavor, and then bias for the actual sounds themselves and that's just a few categories.

As for placebo, it's questionable if it's even bias since hearing is all in the mind: we all obviously believe we are hearing what we're hearing, and that's what makes it heard.  Maybe everything we hear is placebo.


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## bigshot (Jul 24, 2018)

Bias is bias. Off the top of my head, the forms that apply most to sound reproduction and the disease of audiophilia nervosa are...

Confirmation Bias: "I paid a lot of money for this and my casual impression is that it is better, so I'll dismiss a controlled test showing that it sounds the same as less expensive ones."
Halo Effect: "The connectors are 14K gold plated and they shine in the sun, so it must sound better!" "These are the cables that Pink Floyd uses!"
Attentional Bias: "I don't care if the AES says it isn't so. I only believe the ads I read about it in Stereophile!"
Actor Observer Bias: "I thear it with my casual listening. If you don't hear it with your controlled test, it must be your ears or your crappy equipment!"
Anchoring Bias: "When I bought this, the magazine review told me that this was the best amp I could buy. I don't care if the measurements say differently."
Misinformation Bias: "Everyone says that lossless sounds better than lossy. I used 320 LAME MP3s a long time ago with my iPod and it sounded terrible."
False Consensus Effect: "Everyone knows that all amps don't sound the same."
Optimism Bias: "Every one of the components in my system is perfect! It couldn't be better. I'm good at picking 'em!"

Placebo is confirmation bias crossed with anchoring bias.

Human hearing is VERY well documented. The thresholds of perception have been established for nearly a century. The way our mind processes what we perceive may not be as well understood. But that is more how we think, not how we hear.

Psychoacoustics is quite well understood and continues to advance. That is the basis behind audio compression codecs.


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## castleofargh

GrussGott said:


> I guess I was asking specific to human hearing - like for music and stuff.
> 
> For those not aware, there's a field of research called psychoacoustics which basically integrates objective and subjective analysis to determine sound quality or lack thereof.  It's obviously used in audiology, but also for industrial and commercial studies for things like factory noise, airplane noise, venue ambiance, product design, etc.
> 
> ...


 I always demand to get babies and german shepards out of the room when conducting a listening test. I've been very strict about this. 

 most of the biases we care to eliminate in a listening tests are things unrelated to sound. because we came up with that strange avant-garde idea that a listening test should be about sound. so we set up conditions where, hopefully, sound will be the only independent variable, the only cause for a change in our impressions. that way we can at least try to directly correlate sound and impressions. it's also much easier for others to try and replicate the experience if we don't have an unknown number of external factors to deal with. that in turn adds repeatability which with time will allow for the bulk of similar experiences to become usable knowledge for the community. so it's really win-win to go the blind test way.  
a sighted test ruins that attempt at correlating sound and impressions by introducing many unwanted factors. we still have impressions but we can't demonstrate that sound caused them. 

now with all that said, given the typical magnitude of variations in sound from a USB cable, a listening test is not really the first thing I would care about. the USB cable is a piece of passive equipment supposed to have as little impact on the signal as possible. so measuring fidelity should be the first and foremost concern IMO. if we get high fidelity, then the cable is doing a great job, the end.


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## gregorio

GrussGott said:


> [1] Sounds a bit contradictory, Greg.  [1a] Readers and posters should consider that the URL is "head-fi.org" and that no poster (<- don't forget the 't' !) here is a digital signals processing scientist.
> [2] So, can the DAC recover from all errors perfectly and, if not, is that audible?
> [3] What he [atomicbob] finds in his non-leisurely testing is that generic cables like monoprice perform horribly and others, like the AQ Carbon perform great.
> [3a] Thus, if you agree with Bob's testing methodology, from a scientific perspective, AQ cables are less likely to have their transmission effected.
> ...



1. It's only contradictory if you don't understand science and scientific publication! For example, it's not required that posts here be peer reviewed before they're made public.
1a. And now you're going round in circles, ignoring questions/responses and simply repeating the same thing. Again, do I need to be a research geologist in order to state that the earth is not flat?

2. At last, you're actually asking questions rather than making absolute statements as you have in the past! Are there errors, how many errors, can a DAC recover from errors, is it audible? Is completely different from the absolute statements you said you would "feel unethical" about and yet made anyway, which effectively were: "There will be errors, they will not be corrected, you will hear them".

3. Hang on, you're making an interpretation and absolute statement of fact based on that interpretation and yet by your own admission you have little/no knowledge/credentials, let alone are actually a "digital signals processing scientist"! Hypocritical or what? Atomicbob did NOT find that something like monoprice performs horribly and AQ Carbon performs great, he didn't even test their performance, he ONLY tested the resistance of the cables! Does the difference in shield resistance actually cause the USB signal to go out of USB spec? If so, then the cable is not a USB spec cable. If not, then it is incumbent on the DAC to accurately recover the data from a USB spec signal otherwise it is an out of spec USB DAC.
3a. Any affect on transmission is irrelevant unless it's great enough to cause the USB signal to go out of spec.
3b. Again, Bob did NOT show us that transmission-induced errors "happen", he didn't even test USB signal integrity: "_Please remember all that is being tested is the shield connector resistance_"!

4. That's a shame, back to absolute statements of fact which completely contradict the actual facts. Haven't you learned your lesson? Even ignoring the you not being a scientist nonsense and hypocrisy, you're just making up nonsense and making yourself look ignorant and foolish (and/or a troll), AGAIN. Unless you're sure and can back up your "facts", then ask a question (as you have in point #2) or at the very least, phrase your statement extremely conditionally. To actually address your point: It's trivially easy to both define and measure what is "correct" about re-produced audio. Simply take the produced audio and compare it with the re-produced audio, IE. Compare the input signal to a piece (or chain) of audio reproduction equipment and compare it to the output signal. 
4b. What's biology got to do with it? Compare the input signal with the output signal using for example, a simple Null Test. If the result is "null" then the reproduction is PERFECTLY "correct"! This can be done inside just about any audio editing software in a few minutes or simply use free software like RIAA. It's all hardware, software and actual objective measurements, no biology involved! 
4c. That's not even the state of science decades ago, let alone today! Making false statements does not benefit anyone, not me, not other members/visitors to this sub-forum and certainly not you, because false statements will be refuted. 
4d. Ah, so you can demonstrate/prove your statement of "scientific fact" then. Great, let's see it!



jagwap said:


> 1. No. And you know it.
> 2. A DAC IC never has an internal clock. If you meant the clock in the "DAC box" then yes, the internal clock.
> 3. Ground loops exist between equipment, and you know that.



1. What is the practical and audible difference between an error which is "interpolated out" or replaced by resending the packet?
2. Agreed then, the DAC's internal clock.
3. Isn't that an issue of the equipment then, rather that an issue with the cable?

G


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## Phronesis (Jul 25, 2018)

We need to be careful to avoid confusion regarding biases, placebos, hearing, and perception.

The info @bigshot found regarding cognitive biases is good.  We're prone to systematic errors in our perception, memory, judgment, decision-making, etc., and those errors usually happen without our awareness, which means they're mainly due to what happens at a subconscious level.

Placebos are generally introduced intentionally, because it's understood that they can have a powerful effect on our minds and bodies, despite our having a limited understanding of how those effects occur.  We can view good aesthetics of audio equipment as a type of placebo.  Placebo effects aren't merely 'fake', they correspond to real changes in the brain which can affect how things sound to us and our enjoyment of music.  I think it's pragmatic to cost-effectively use placebo effects to our advantage, especially given that they can operate even when we consciously know that they're placebo effects.

'Hearing' is somewhat understood in terms of what the ear does, thresholds of detection, etc.  But we have a LOT still to learn about perception of sound and music.  This recent paper which I've cited before has some important findings, and not much research of this type has been done so far:

https://www.nature.com/articles/s41598-018-24528-3

"Although the _cognitive_ processes underlying framing bias have received increasing attention in recent years, there is surprisingly scarce evidence regarding the _neural_ mechanisms that underlie decision-makers’ ability to reduce the influence of contextual information to form a less biased (or more objective) decision."​
For those who're interested in these topics in general, I highly recommend reading the book "Subliminal: How Your Unconscious Mind Rules Your Behavior" by Leonard Mlodinow.  It's highly relevant to audio.


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## gregorio

GrussGott said:


> And since hearing is similar to pain - modulated by the brain - and [1a] since we don't understand how the human brain "hears" or [1b] what "should be heard" .... is the concept of placebo even applicable in listening to music?



This is another whole can or worms, in fact several cans of worms! However, it's effectively all a red herring because human hearing/perception has nothing to do with USB cables. As mentioned in my previous post, we can measure/compare the input signal with the output signal and arrive at a precise objective determination of signal integrity with no involvement of human aural perception and biases.

Although unrelated to the fidelity/integrity of USB data transmission through USB cables and DACs, and is therefore effectively off-topic, it is maybe worth briefly answering your question:

The strict answer to your question is "No"! Strictly speaking, "placebo effect" is only applicable to medical treatments. However, it is commonly (though technically incorrectly) used here and in the audio community as a "catch all" term for the effects of a range of cognitive biases and the peculiarities of human hearing perception. Used in this sense, not only is "placebo" applicable to listening to music, it's absolutely vital because without it there is no music! Without placebo (cognitive biases and the propensities of human perception) all that actually exists is just semi-random noise!

1a. You just made that up! You are again employing a logical fallacy; just because we (humankind) do not know everything does NOT mean we don't know anything. We don't know everything about the formation of this planet but does this invalidate the statement that the Earth is not flat? *When you say "we don't understand", do you really just mean you don't understand?* You seem incapable of following through your statements logically, of asking yourself what are the consequences of your statements if you follow them through to their logical conclusions? For example, the logical consequence of a statement like "we cannot transfer digital data as an electric signal down a wire bit perfectly" is that there would be no "digital age" because all digital devices would crash every few seconds. 

1b. Again, you're not considering the logical conclusion or consequences if you're statement were actually true. If we do not know what "should be heard", then what is it that music composers do? If composers have no understanding of "what should be heard", do they just write random dots on a piece of manuscript? Were Bach, Mozart and Beethoven just astronomically lucky or were they composing on the basis of a very good understanding of what should be heard/perceived? Does 6+ centuries of music theory and composition development not exist? 

G


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## bigshot (Jul 25, 2018)

Preference is almost always colored by bias. But you don't have to test to determine your own preference. You do that automatically with every decision you make. Controlled tests are designed to minimize bias so you can get an objective answer to a question... Like "Does this USB cable alter the sound?" That is a very simple thing to test for. It was done back when digital audio was first being sent through a USB cable. The question has been answered for years. Yet bias keeps leading people to the wrong answer. And here we are wasting our energy spinning our wheels on dumb topics like this.

A person has to make a little bit of effort to NOT be influenced by bias. When I see people questioning the validity of the scientific process and controlled tests, I know that bias has a strong grip on them. They're cherry picking for the sole purpose of eliminating the best method for filtering out their bias. They are allowing bias to even color their analytical thinking process. I really think that schools should teach logic and critical thinking skills along with grammar and times tables. Critical thinking is an important life skill.


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## Phronesis

Measurement is objective.  Any test involving listening involves _subjective_ perception and is therefore subject to bias and misperception, whether blinded or not.  Blinded listening tests are NOT in the same category as blind testing used in medicine, where you're comparing outcomes for separate groups using objective criteria.  It is too common for people to naively assert that because someone couldn't detect and report a difference in a given blind listening test, they necessarily didn't perceive a difference at conscious or subconscious levels.


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## bigshot (Jul 25, 2018)

Multiple tests, multiple test subjects, statistical analysis... you end up with an objective threshold. It may not be exactly applicable to every individual individually, but you end up with a nice objective bell curve that gives you a nice objective idea of what the truth is. Testing of medicine is exactly the same.

I don't think subconscious "perception" has anything to do with listening to music in the home. I know I listen to music consciously. I don't think I'm alone in that. The whole "subconscious" hearing thing is a red herring designed to justify inaudible frequencies. There was a test presented at the AES that statistically showed that super audible frequencies added absolutely notihing to the perceived quality of recorded music. Inaudible is inaudible.


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## castleofargh

are we so deep down the rabbit hole that we're now seeking euphonic ways to corrupt digital signal by mean of a USB cable? is USB cable a new form of DSP to play with in the mind of hyper subjectivists? 
if not, then who cares about subjective impressions? even @GrussGott has been pretending to be concerned about accurate retrieval of the digital signal and such notions of objective fidelity. you measure the output signal somewhere, check if it's close to the reference signal, and you know if out of 2 USB cables, one really is crap. the end.




Phronesis said:


> Measurement is objective.  Any test involving listening involves _subjective_ perception and is therefore subject to bias and misperception, whether blinded or not.  Blinded listening tests are NOT in the same category as blind testing used in medicine, where you're comparing outcomes for separate groups using objective criteria.  It is too common for people to naively assert that because someone couldn't detect and report a difference in a given blind listening test, they necessarily didn't perceive a difference at conscious or subconscious levels.


 there are many clinical trials with the same types of issues and requirements as a blind listening test. I have no idea why you'd try to create a dichotomy between blind testing and blind testing? 
as for the naive assertion, a blind test starts with a null hypothesis which is our default stand on the experiment as long as we don't get evidence saying otherwise. failing the test doesn't prove or disprove the hypothesis, so of course what we have at that time is... an hypothesis. but there is nothing wrong with keeping that assumption until we have reason to think otherwise. a failed test certainly doesn't provide much motivation to dismiss the null hypothesis. 
on the other hand, a guy who fails a blind test but keep claiming he's hearing a difference, now that's naive IMO.


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## bigshot

Assuming that digital audio is subject to the same sorts of error that analogue audio is subject to is naive too.


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## Phronesis

bigshot said:


> Multiple tests, multiple test subjects, statistical analysis... you end up with an objective threshold. It may not be exactly applicable to every individual individually, but you end up with a nice objective bell curve that gives you a nice objective idea of what the truth is. Testing of medicine is exactly the same.
> 
> I don't think subconscious "perception" has anything to do with listening to music in the home. I know I listen to music consciously. I don't think I'm alone in that. The whole "subconscious" hearing thing is a red herring designed to justify inaudible frequencies. There was a test presented at the AES that statistically showed that super audible frequencies added absolutely notihing to the perceived quality of recorded music. Inaudible is inaudible.



Most of what happens in hearing, listening, and perception happens subconsciously.  The conscious part is the part we're most directly aware of.  The two aren't really separable, because there could be no conscious perception without the subconscious part working behind the scenes, and without the conscious part we don't even know that we're hearing.  Look into 'blindsight' - people can sort of 'see' without the conscious experience of seeing.



castleofargh said:


> are we so deep down the rabbit hole that we're now seeking euphonic ways to corrupt digital signal by mean of a USB cable? is USB cable a new form of DSP to play with in the mind of hyper subjectivists?
> if not, then who cares about subjective impressions? even @GrussGott has been pretending to be concerned about accurate retrieval of the digital signal and such notions of objective fidelity. you measure the output signal somewhere, check if it's close to the reference signal, and you know if out of 2 USB cables, one really is crap. the end.
> 
> there are many clinical trials with the same types of issues and requirements as a blind listening test. I have no idea why you'd try to create a dichotomy between blind testing and blind testing?
> ...



I'm all for objective fidelity in digital signal transmission.  Let me know when you guys pin down the error rate.

The blind part of blind listening tests is good.  I don't really see any downside, other than the hassle of doing it, and the upside is that it should eliminate biases due to expectations, etc.  The problem with blind listening tests is that they still rely on judgments of a subjective perceiver, with the associated problems with memory and perception at both conscious and subconscious levels.  Blinding can't entirely eliminate those problems.


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## bigshot

Enough samples, enough people tested and the perceptual bias isn't really an issue any more. Over the spread of so many different people, it all cancels out. It's the same as testing medicine. Some people aren't cured, some people might be cured. If you have a big enough sample, you can determine if it's effective overall.

Preference is a little dicey, but with enough people, you can come up with a general conclusion. The easiest thing to determine is audible thresholds though. You just give people two samples, make a bunch of tests to see if they can tell the difference and see if any of it reaches a statistical conclusion.

Each individual test may have an element of subjectivity, but the overall pattern of all the tests can show objective facts. Too many people used subjectivity as an excuse to poo poo controlled listening tests. That's throwing the baby out with the bathwater. You just need to apply the proper controls to minimize subjective error.


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## pinnahertz

Phronesis said:


> The blind part of blind listening tests is good.  I don't really see any downside, other than the hassle of doing it, and the upside is that it should eliminate biases due to expectations, etc.  The problem with blind listening tests is that they still rely on judgments of a subjective perceiver, with the associated problems with memory and perception at both conscious and subconscious levels.  Blinding can't entirely eliminate those problems.


Sure they can.  Using a real ABX comparator along with proper test design eliminates memory problems because the comparison is instantaneous, and eliminates perception issues with multiple testers of a statically significant number, along with each doing a statically significant number of trials.  The test is double-blind because the tester doesn’t know what A,B or X is, and the test admin doesn’t know what X is until data is collected as it changes randomly with each trial.  Yes, an ABX test relies on subjective judgement, but that’s the entire point.  It is one of the few ways to determine what is and is not an audible difference. 

BTW, a real ABX test includes a trial set where A,B and X are identical as a sort of control/calibration.


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## Phronesis (Jul 26, 2018)

pinnahertz said:


> Sure they can.  Using a real ABX comparator along with proper test design eliminates memory problems because the comparison is instantaneous, and eliminates perception issues with multiple testers of a statically significant number, along with each doing a statically significant number of trials.  The test is double-blind because the tester doesn’t know what A,B or X is, and the test admin doesn’t know what X is until data is collected as it changes randomly with each trial.  Yes, an ABX test relies on subjective judgement, but that’s the entire point.  It is one of the few ways to determine what is and is not an audible difference.
> 
> BTW, a real ABX test includes a trial set where A,B and X are identical as a sort of control/calibration.



Let's break it down:

- Instant switching does NOT eliminate memory problems.  Things are always being heard in a sequence, with a comparison of what was heard previously, hence use of memory.  If you listen to A then B, with instant switching, you're still listening to B in real time and comparing with a memory of A.  For that matter, even listening in real time requires use of memory, since there can be no perceived sound for an instant of time.  Sound and its perception involve the time dimension and are dynamic, not static.

- Using multiple testers will give you data for a group, and the perception of individuals in a group is likely to vary.  If the question is what differences a particular person hears or doesn't hear, you want to test only that person rather than mixing their data with group data.

-  Whether you test a group or an individual, you can't 'eliminate perception issues'.  You can't have hearing without perception!

-  Doing a large number of trials is needed to make statistical claims, but perception need not be consistent from trial to trial.  Someone may really hear distinct differences in say 5% of the trials, resulting in a result which is unimpressive statistically, yet they really did hear differences *some* of the time.  Statistics aren't some sort of magic which removes all subjectivity and makes everything objective.  With listening tests, there's always subjectivity, and statistics may even mislead us about what's really going on by mixing variable things together.

Ultimately, I see tests like double-blind ABX listening tests as an attempt to give an aura of scientific and quantitative rigor which they don't really have, and such tests can be quite misleading when the underlying processes of perception and memory aren't delved into.  It can become garbage in/garbage out if the tester just crunches numbers without trying to understand the psychological aspects of the testing.  Blinding eliminates expectation bias, but the other issues with perception and memory remain.  All of this said, I'm not trying to imply that casual sighted listening comparisons are better - while they have the benefit of a 'naturalistic' setting, they have their own problems, and arguably the problems may be even worse than with a double-blind ABX test with good controls and instant switching.

Even in medicine, consider that a drug which does well against a placebo in a randomized double-blind trial will generally not have the same beneficial and side effects for each person using the drug.  The benefits and side effects will vary across patients, and only in aggregate can you say that the net benefits were found to outweigh the net side effects.


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## Whazzzup (Jul 26, 2018)

Statistical significance has to be high with a very low margin of error, to prove a theory. Like 95% or greater, 98% repeatable results is good enough. Course experiment controls are other issues to eliminate confounding errors.


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## gregorio

Phronesis said:


> [1] I'm all for objective fidelity in digital signal transmission. [2] Let me know when you guys pin down the error rate.
> [3] The blind part of blind listening tests is good.



1. Why is that not the end of the story then?
2. I can't speak for others but the reason I haven't been able to "pin down the error rate" is because when I've specifically tested USB cables I haven't detected any errors attributable to USB cables, with some obvious exceptions such as damaged USB cables.
3. Again, what has blind testing got to do with USB cables? Either a USB cable is passing data bit perfectly or it's not and we can measure that, it has nothing to do with human hearing, perception or biases.

G


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## Phronesis

gregorio said:


> 1. Why is that not the end of the story then?
> 2. I can't speak for others but the reason I haven't been able to "pin down the error rate" is because when I've specifically tested USB cables I haven't detected any errors attributable to USB cables, with some obvious exceptions such as damaged USB cables.
> 3. Again, what has blind testing got to do with USB cables? Either a USB cable is passing data bit perfectly or it's not and we can measure that, it has nothing to do with human hearing, perception or biases.
> 
> G



I see the USB and blind testing as pretty much two different discussions. 

People who think USB cables might affect sound should probably just spend a few bucks more to get cables that look good and have a good reputation, enjoy any real and placebo effects they might offer, and call it a day.


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## gregorio

Phronesis said:


> [1] People who think USB cables might affect sound should probably just spend a few bucks more to get cables that look good and have a good reputation, [2] enjoy any real and placebo effects they might offer, and call it a day.



1. It's not just a few bucks more, it's typically hundreds or thousands more.

2. What real effects? ... So, we're effectively talking about paying hundreds/thousands of dollars more, just for placebo effects. I've got no problem with that, if someone wants to spend hundreds/thousands more for placebo effect, that's entirely up to them, even if they want to spend hundreds/thousands more for not even placebo effect, say just for a more attractive visual appearance, that's absolutely fine. What's clear though from this and other threads, is pretty much without exception, those who've spent the hundreds/thousands on audiophile USB cables have done so under the belief that they're getting some real audible audio improvement. As far as some of the most vociferous extremist audiophiles are concerned my view is; fine, serves them right, I sure they and their placebo will be very happy together, right up until their biases are manipulated by some new marketing BS. However, what I strongly object to is when aspiring/newbie audiophiles or just those looking to improve their systems are authoritatively/forcefully advised by those vociferous extremist audiophiles of the "real" benefits of audiophile USB cables.

G


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## Phronesis

gregorio said:


> 1. It's not just a few bucks more, it's typically hundreds or thousands more.
> 
> 2. What real effects? ... So, we're effectively talking about paying hundreds/thousands of dollars more, just for placebo effects. I've got no problem with that, if someone wants to spend hundreds/thousands more for placebo effect, that's entirely up to them, even if they want to spend hundreds/thousands more for not even placebo effect, say just for a more attractive visual appearance, that's absolutely fine. What's clear though from this and other threads, is pretty much without exception, those who've spent the hundreds/thousands on audiophile USB cables have done so under the belief that they're getting some real audible audio improvement. As far as some of the most vociferous extremist audiophiles are concerned my view is; fine, serves them right, I sure they and their placebo will be very happy together, right up until their biases are manipulated by some new marketing BS. However, what I strongly object to is when aspiring/newbie audiophiles or just those looking to improve their systems are authoritatively/forcefully advised by those vociferous extremist audiophiles of the "real" benefits of audiophile USB cables.
> 
> G



The $20 cables mentioned in this thread look pretty good to me.

I don't know whether more expensive USB cables have any benefits with respect to sound.  I'm doubtful, and I place the burden of proof on those who make such claims.  Without strong evidence, I agree that it's inappropriate to much such claims.  But we should remember that those who make such claims typically sincerely believe that they've heard clear differences, and are unaware of how substantially their auditory perceptions can be influenced by expectations.  The real solution to all of this would be to do a lot more testing, in a proper way, but there's lack of funding to do so.


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## Arpiben

@Phronesis
What perception bias leads people to believe charlatans rather than professionals ?
Tell them that as digital transport, cables (USB,Coaxial,Optical,..) are error free they will keep refuting it. Lack of magic maybe.


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## Phronesis (Jul 26, 2018)

Arpiben said:


> @Phronesis
> What perception bias leads people to believe charlatans rather than professionals ?
> Tell them that as digital transport, cables (USB,Coaxial,Optical,..) are error free they will keep refuting it. Lack of magic maybe.



I think that people often want to believe sales pitches because they're continually searching for a higher high in sound, and hoping that product X will give that to them - they want the sales pitch to be true, so they're inclined to believe it.  And if the cost involved is disposable income, there isn't much incentive to worry about wasting money.  And if they buy the product and it sounds better to them due to expectations, the loop becomes closed, reinforced, and perpetuated.

With many people, I see an element of addiction and obsession when it comes to audio.  I personally am kind of done searching for audio upgrades with my gear, at least for a while, and lately have been enjoying just listening to music.


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## bigshot

I still have upgrades I'd like to do, but it involves more channels, more speakers and a whole lot more money.


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## Glmoneydawg

bigshot said:


> I still have upgrades I'd like to do, but it involves more channels, more speakers and a whole lot more money.


Lol...yep...you guys have ruined digital "upgradeitus" for me.Speaker upgrades are a lot more expensive and complicated....thanks


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## bigshot

I'm itching for Atmos!


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## sonitus mirus

A post made 8 years ago by @nick_charles provides numerous references about this topic.

https://www.head-fi.org/threads/how...make-a-difference.481385/page-25#post-6598849


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## Vaskedama

Currawong said:


> And noise, which is where I think the issue has been. Supposedly Schiit Audio's new Eitr solves that by using ethernet isolation transformers to block it.



If Noise is the problem, then running a dual conversion UPS to your pc and to your audio setup will be the better choice as this should eliminate most, if not all of the line noise. The good thing about this is that it has the benefit of science behind it.


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## GrussGott

Vaskedama said:


> If Noise is the problem, then running a dual conversion UPS to your pc and to your audio setup will be the better choice as this should eliminate most, if not all of the line noise. The good thing about this is that it has the benefit of science behind it.


oh boy.


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## Currawong

Vaskedama said:


> If Noise is the problem, then running a dual conversion UPS to your pc and to your audio setup will be the better choice as this should eliminate most, if not all of the line noise. The good thing about this is that it has the benefit of science behind it.



An additional problem appears to be that the USB transmitting and receiving chips themselves generate noise, which any kind of power supply cannot help with. This is supposedly the reason why software that exclusively controls the USB hardware during audio transmission can improve the sound, as the USB hardware is doing less processing and producing less noise. Of course, isolation should eliminate this issue on at least one end, if not the other.


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## gregorio

Vaskedama said:


> If Noise is the problem, then running a dual conversion UPS to your pc and to your audio setup will be the better choice as this should eliminate most, if not all of the line noise. The good thing about this is that it has the benefit of science behind it.



Assuming a very abnormal amount of noise on the power line and a DAC only designed to deal with a normal amount of noise, then a double-conversion on-line UPS would help. But, it would only help if BOTH those conditions are met and that would be a rare. In the vast majority of cases, a noise problem would have nothing to do with the power supply, most commonly it would be an under-powered amp but in a few cases it *could* be a computer outputting a large amount of noise/interference through it's USB output and a DAC not sufficiently designed to isolate or reject that noise.

G


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## Vaskedama

If the USB chips are producing noise then a good USB cable is not going to eliminate that.


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## gregorio

Vaskedama said:


> If the USB chips are producing noise then a good USB cable is not going to eliminate that.



Correct, neither a USB cable nor a UPS will correct for noise produced or passed through the USB chips. The solution is to isolate the DAC's output from that noise.

G


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## Vaskedama

I guess something like this would be in order:
http://www.schiit.com/products/eitr


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## gregorio

Vaskedama said:


> I guess something like this would be in order: http://www.schiit.com/products/eitr



Sure, that would probably do the trick OR, you could just buy a DAC that's competently designed in the first place and internally isolates it's output. And you can buy DAC that does that for less than the cost of the unit you suggest!

G


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## Steve999 (Nov 10, 2018)

gregorio said:


> Sure, that would probably do the trick OR, you could just buy a DAC that's competently designed in the first place and internally isolates it's output. And you can buy DAC that does that for less than the cost of the unit you suggest!
> 
> G



You guys just made me paranoid about my computer adding noise so I just hooked up a $30 USB-powered DAC I had lying around. It weighs just a few ounces and has a headphone amp built in too just to add to the blasphemy. I have no idea if it sounds any better but it drives my Beyers louder than my computer does so I'm happy about that. The USB out device shows up as Speakers (USB Audio CODEC) on my computer audio settings. I have a pretty purple DAC that is more versatile lying around somewhere. . . I'll have to track it down. As far as the subject of USB cables, it runs from the computer to the DAC by a USB cable and in fact is solely USB powered, so this is actually on-topic. I can't imagine how it would add any noise because it's it's external.

Edit: After rummaging around I found all three of my USB external DACs. They all work fine. They range from $30 to $70 to $200. They can all double as headphone amps. I imagine to myself that the pretty purple one sounds the best. The $70 one and the $200 one have lots of extra functions. I have accumulated them over the course of about 15 years for various purposes. They're all good at different things (aside from sound reproduction). I don't regret for a moment any of the three purchases, although the $70 one was a present. I'll probably use the $200 one the most for headphones from my computer as it has adjustable crossfeed and a rechargeable battery. The $30 one has a tiny bit of noise if you turn it up to unrealistic ear-bleeding volumes. The other two get even louder and are dead silent. The $30 one and the $70 one also have phono preamps. The $30 and the $70 one can run on USB only--no external power source needed. That should help to eliminate one more possible source of noise. The $200 one has tone controls and as I said continuously adjustable crossfeed and can run on AC or its rechargeable battery. I'm listening to the pretty purple one right now. I made sure they all work as DACs from my computer and they do.


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## gregorio (Nov 13, 2018)

Steve999 said:


> You guys just made me paranoid about my computer adding noise so I just hooked up a $30 USB-powered DAC I had lying around....
> ... After rummaging around I found all three of my USB external DACs. They all work fine.



Yep, that's entirely expected. It's true that the USB interface is potentially relatively noisy, computers have CPUs, GPUs and other components chugging away, producing all kinds of noise/interference and few are particularly vigilant about making sure none of it finds it's way out of it's USB port. Plus, you've got power potentially being delivered out of the port as well. All this sounds rather worrisome to all the paranoid audiophiles out there but there's some additional facts that HAVE to be taken into account:

Unlike analogue audio, digital audio is completely immune to/unaffected by transmission noise. What we're left with then, is the possibility of noise/interference finding it's way into the analogue section of the DAC. However, *IF* a particular DAC is sensitive to this noise, it's sheer INCOMPETENCE of the part of that DAC's designer, because: As virtually all computers output a relatively high amount of noise AND as it obviously isn't difficult nor expensive to isolate the DAC from this noise (as even many/most very cheap DACs manage it), what the DAC designer is effectively saying is that they haven't designed their USB DAC for use with "virtually all computers"!! This is not dissimilar to the mains power supply issue: Most/Virtually all mains power supplies fluctuate somewhat and have noise. However, that's always been the case and therefore it's completely expected/required (and relatively cheap/easy) as part of the design procedure to overcome that potential issue. It a particular DAC doesn't, then it's INCOMPETENTLY designed because it's a mains powered device which apparently hasn't been designed to operate optimally with "virtually all mains power supplies"!

In reality, the worst measurements I've seen for DACs susceptible to computer noise via the USB port are some of the Schitt DACs but even then, we're talking about noise down below -80dB, which should be entirely inaudible without additional factors, some fairly serious gain staging mismanagement on the part of the user for example. Why are some/many audiophiles so paranoid about the issue then? Well, Schitt should really have done a better job, as other DACs manage to get the noise below -100dB and some cheap ones even manage about -120dB but mainly, the paranoia is the result of marketing. There's lots of audiophile USB cable and USB purifiers products out there that HAVE to misrepresent the facts as a real problem, a problem which their product solves/cures. In reality, it's a "real problem" for virtually no one, maybe if you're unlucky enough to have a computer which produces more noise on it's USB port than 99% of other computers AND if you have a DAC that's a lot more susceptible to noise than a cheap DAC should be AND if you have a gain staging issue. I saw an example of this sort of thing here on head-fi some while ago. An audiophile was continually advising everyone that a power conditioning UPS was absolutely essential audiophile equipment and was absolutely adamant about the improvement it made. After many pages, it turned out this audiophile lived on a farm somewhere that relied on it's power supply from an ancient diesel generator which had been on it's last legs for years (but he couldn't afford to replace it). A conditioning UPS provided a relatively cheap and obviously superior result, which he then (fallaciously) extrapolated as similarly obvious and vital for EVERYONE serious about music reproduction, and anyone who disagreed with him must either be deaf, ignorant, just lying/"trolling" him or all three!

G


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## Currawong

While you are correct, it's unreasonably to consider manufacturers to be incompetent -- you have, in effect, declared this of literally every single manufacturer who has added a USB input to their digital hardware. If you have designed your own DAC immune to these issues, then it'd be fair. The manufacturers I know, not dissimilarly to you, believed that USB noise wasn't a big problem until they experimented with improving it after feedback from customers.


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## gregorio

Currawong said:


> ... it's unreasonably to consider manufacturers to be incompetent -- you have, in effect, declared this of literally every single manufacturer who has added a USB input to their digital hardware.



That's EXACTLY THE OPPOSITE of what I actually "declared"!!! I declared that a DAC manufacturer would be incompetent if they designed a USB DAC which could not isolate from computer USB noise sufficiently to be inaudible. I also declared that even the worst measurements I've seen of any DAC (some Schitt models) would be inaudible under any normal conditions. What I've actually declared "in effect" then, is that (as far as I'm aware) NOT a single manufacturer who has added a USB input to their DACs has done so incompetently!

IMO, for what it's worth: Knowing the market they are targeting and as it's clearly quite trivial/very cheap to do so, Schitt should have given themselves a larger margin by providing better isolation from USB noise and should have more thoroughly tested before releasing.

G


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## Steve999 (Nov 13, 2018)

gregorio said:


> Yep, that's entirely expected. It's true that the USB interface is potentially relatively noisy, computers have CPUs, GPUs and other components chugging away, producing all kinds of noise/interference and few are particularly vigilant about making sure none of it finds it's way out of it's USB port. Plus, you've got power potentially being delivered out of the port as well. All this sounds rather worrisome to all the paranoid audiophiles out there but there's some additional facts that HAVE to be taken into account:
> 
> Unlike analogue audio, digital audio is completely immune to/unaffected by transmission noise. What we're left with then, is the possibility of noise/interference finding it's way into the analogue section of the DAC. However, *IF* a particular DAC is sensitive to this noise, it's sheer INCOMPETENCE of the part of that DAC's designer, because: As virtually all computers output a relatively high amount of noise AND as it obviously isn't difficult nor expensive to isolate the DAC from this noise (as even many/most very cheap DACs manage it), what the DAC designer is effectively saying is that they haven't designed their USB DAC for use with "virtually all computers"!! This is not dissimilar to the mains power supply issue: Most/Virtually all mains power supplies fluctuate somewhat and have noise. However, that's always been the case and therefore it's completely expected/required (and relatively cheap/easy) as part of the design procedure to overcome that potential issue. It a particular DAC doesn't, then it's INCOMPETENTLY designed because it's a mains powered device which apparently hasn't been designed to operate optimally with "virtually all mains power supplies"!
> 
> ...



Thanks, lots of great learning there! On the $70 one i've actually got one with a switchable subsonic filter that will help with playback of LPs that I digitized before I got a better hang of digitized LP editing software. It also has line level and phono inputs and a ground I used for my old turntable. And it has pretty purple letters on the top. And digital and analog inputs and digital and analog outputs. COAX, optical, USB, mini, RCA, you name it. It's kind of fun. It's completely USB powered _or_ you can use a power adapter. I am just using USB power through USB 3.1 (i.e., old USB 3.0). I can see the digital optical output ready to do its thing some day in its glowing red way. Right now I'm just going USB out into the DAC and analog out. It's nice to have total dead quiet background silence even at a very high max volume. It inspires confidence in me.

I do have questions as I think of it (I'm using it right now)! I have a three-way switch on it marked "monitor source"--1) pre-amp (no sound comes out) 2) pre-amp plus CPU (nice sound) and 3) CPU only (sounds pretty much just like pre-amp plus CPU).  What's the difference? I am using nice smooth "monitor output level" knob that goes from 0 to 10 for listening to my headphones.

There is also a "gain trim" knob, but it seems to have no effect. It goes from -8 to +8. Maybe that's for other digital ins or analog in or the digital out, to avoid clipping?

Then there is very big purple button marked "_Eleven_" but I am scared to mess with that.

BTW, to keep things on topic, I am using a standard-issue USB cable I pulled out of drawer. It's black with normal metal end points.


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## GrussGott (Nov 13, 2018)

Currawong said:


> While you are correct, it's unreasonably to consider manufacturers to be incompetent -- you have, in effect, declared this of literally every single manufacturer who has added a USB input to their digital hardware. If you have designed your own DAC immune to these issues, then it'd be fair. *The manufacturers I know, not dissimilarly to you, believed that USB noise wasn't a big problem until they experimented with improving it after feedback from customers.*



That's a key point - one of many possible good points - many of which have been hashed out in the thread: anyone that's truly interested can review the last 50 or so pages.

In short, digital signals transmission & processing - and it's audible effect on the music we hear - is a super complex topic, especially when one is attempting to decompose it to a recommendation to a single individual's system.  Variables include their environment, their specific equipment, the files they're running, their biology, etc etc.

Hopefully all science oriented folk will agree we should get our science facts from scientists/engineers _experienced in this specific topic _- which in this case is a digital signals processing scientist or product engineer who has actually experimented with low-level implementations ... the rest is just opinions from amateurs and hobbyists.

Thus, beyond the amateur science opinions, the correct recommendation is always to try it cost-free and, if you can't, assume it won't help.


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## bigshot (Nov 13, 2018)

I've never had any problems with line noise. I don't do anything special to prevent it. I suspect that it's one of those rare problems where there's no doubt that you have the problem when you have it and you just have to deal with it when it crops up. People probably talk about it more than they experience it. I think it used to be more of a problem back in the 70s.

If there was line noise in USB that was reaching the level of causing problems, it would probably be a good idea to just replace the cable or the unit it's plugged into. Buying a fancier cable probably won't help, because it's caused by a defect of design or manufacture. USB is designed to work flawlessly. One should be able to expect it to do just that.


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## GrussGott (Nov 13, 2018)

bigshot said:


> *USB is designed to work flawlessly.* One should be able to expect it to do just that.



So are automobiles and airplanes, yet we all, at a minimum, perform routine maintenance and many of us choose to add modifications.

Personally I don't expect anything to work flawlessly, but that's mostly because, as an engineer, I've yet to experience "flawless" with anything, ever.

And I worked with commercial airplanes for a decade.


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## bigshot (Nov 13, 2018)

Planes and cars are designed to perform in a range of ways... some go fast, some carry lots of cargo, etc. A wire just has one job... to carry a signal from one end to the other without altering it. There's no "faster" or "more cargo" to it. Either it does that flawlessly, or it doesn't. I honestly don't know why people spend so much time talking about wires, because they should be totally invisible. You just plug something in and it works. You don't think about all the wires connecting you all the way to the power generators at Hoover Dam. It seems to me that if there is a problem somewhere, a USB cable is probably going to be one of the least likely places to find it.

I've got hundreds of flawless performers in my house. The fridge keeps my food cold. The microwave makes it hot. The lights light up when I flick a switch. My dog greets me happily when I get home. All of that functions flawlessly. All my wires function flawlessly too. I suppose my microwave isn't flawless at greeting me happily when I get home, but it wasn't designed to do that.


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## GrussGott (Nov 13, 2018)

bigshot said:


> Planes and cars are designed to perform in a range of ways... All my wires function flawlessly too.



Wires are designed to perform in a range of ways as well ... nevertheless ...

*It's a frame of reference thing: * My car is 1 year old, has 5,000 miles on it, and I drove 4,999 of them.  My car has worked flawlessly, in the sense that it always starts and has never done anything other than what I told it to do.

Yet that's not enough for me.  I want more.  and I can get more, so I modify it - not because of problems, but because I want more, i'm always searching for more performance, and I know I can get it.  and I do.

The happiest people are happy with what they have - that sounds like you!  Many don't even consider there could be more, and some don't even believe there could be more, and that's ok because they're happy with what they have!

Me? i want more.  but that's only because I know there is more to have.


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## bigshot

I guess my priority is sound fidelity. If more and better don't make any audible difference, it doesn't do anything for me. I'd rather spend my energy and money on something that produces better sound quality.


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## GrussGott

bigshot said:


> I guess my priority is sound fidelity. If more and better don't make any audible difference, it doesn't do anything for me. *I'd rather spend my energy and money on something that produces better sound quality.*



Me too!  MOAR!

That's why I have nice cables (including USB) - cause they produce better sound quality in my setup.  See?  I guess we are all after the same thing ... huh.


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## Steve999 (Nov 13, 2018)

GrussGott said:


> Me too!  MOAR!
> 
> That's why I have nice cables (including USB) - cause they produce better sound quality in my setup.  See?  I guess we are all after the same thing ... huh.



You did all of that great reading a few months ago. We both learned that the USB chain is massively more complex than I might have guessed. I was impressed with your honesty and your curiosity. But can you show me something credible that shows that there is any audible difference between non-defective cables? If so, let's hit it! If not, LEARN!!!! You are a BRIGHT guy!

Oh, and by the way, maybe you could post something in the Sound Science music thread. I get lonely there.


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## GrussGott (Nov 13, 2018)

Steve999 said:


> You did all of that great reading a few months ago. We both learned that the USB chain is massively more complex than I might have guessed. I was impressed with your honesty and your curiosity. But *can you show me something credible that shows that there is any audible difference* between non-defective cables? If so, let's hit it! If not, LEARN!!!! You are a BRIGHT guy!



Well Steve, I'm a big fan of experience being the best teacher, so here's what I can show you:

(1.) go to any credible gear shop
(2.) buy whatever nice cables you want to test - they'll have a minimum of 30 day free returns, most will have 45 or 60 days
(3.) Listen.

If you don't hear anything different, return them; If you hear something you like, keep them.

Ain't no learnin better than first-hand experience, and in this case your lesson is free!*

* alternatively you can spend the next decade becoming a digital signals processing expert and design your own USB implementation - experience seems easier


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## Steve999 (Nov 13, 2018)

GrussGott said:


> Well Steve, I'm a big fan of experience being the best teacher, so here's what I can show you:
> (1.) go to any credible gear shop
> (2.) buy whatever nice cables you want to test - they'll have a minimum of 30 day free returns, most will have 45 or 60 days
> (3.) Listen.
> ...



I've done double-blind testing. I heard no difference. Maybe your ears are better. Try it!

Or if you want to read about a lot of other people who tried it, with no one ever being able to hear a difference, not one person, go to the first post in the first thread in this sub-forum. There is a massive amount of book learning you can do, which I know you are capable of.

This may be a case where the truth is painful for you, but you only live once, eh? I like to see the world as it is, within my personal limits. I have been very wrong about things before, as has been every adult human being who ever inhabited this planet.


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## GrussGott

Steve999 said:


> I've done double-blind testing. I heard no difference. Maybe your ears are better. Try it!



I did!  And we know the way this goes:

* "this amateur science stuff proves correct!"
* "no this amateur science stuff say that amateur stuff is wrong and this science stuff is correct!"

*Net-net: *my empirical data says go.  your empirical data says stop.   We're both amateurs unqualified to explain our results, _as is everyone else here. _ The difference seems to be I know I'm an amateur unqualified to make global statements of fact about engineered products and you don't.


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## GrussGott (Nov 14, 2018)

This seems relevant here:

Paul McGowan of PS Audio on USB cables at RMAF 2018:

_While at RMAF a young group of fellow YouTube channel contributors approached me with folded arms and a challenge. They had purchased at Best Buy the cheapest USB cable they could find. Their challenge to me was to prove to them a difference between their cable and my high-performance cable mattered.

“No problem,” said I and invited them to Music Room One after the show. Within the first 30 seconds of the comparison the looks of shock on their faces was a sheer joy to me. Here were four bright young men intent on being right that cables cannot matter, yet open-minded enough to actually give it a try. After demonstrating the differences I left the room and their leader *proceeded to test them with blind ABs and the group fared well: 70% accurate choices. Not bad for inexperienced listeners.* (Yes, listening is a learned skill).

Do they always matter? No, they do not. _​
https://www.psaudio.com/pauls-posts/interconnects-and-speaker-cables-matter/
(btw - i believe the "young group" was DMS, Zeos, and Joshua Valour ... Metal571 may have been there too)


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## Steve999 (Nov 14, 2018)

Steve999 said:


> I've done double-blind testing. I heard no difference. Maybe your ears are better. Try it!





GrussGott said:


> I did!  And we know the way this goes:
> 
> * "this amateur science stuff proves correct!"
> * "no this amateur science stuff say that amateur stuff is wrong and this science stuff is correct!"
> ...



Good. You're learning. I'm one of the least knowledgeable people here about electronics and hifi. You can take it up with the experts here. They'll be much more likely to engage you as you show some effort and understanding. I know what I don't know. No need to throw around silly accusations. You'll just end up down the same path you've been on. Which is no big deal. Just don't expect the cats here to cut you any breaks. 

And maybe you could post something in the Sound Science music thread!


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## gregorio

GrussGott said:


> [1[ In short, digital signals transmission & processing - and it's audible effect on the music we hear - is a super complex topic ...
> [2] Variables include their environment, their specific equipment, the files they're running, their biology, etc etc.



1. Everything can seem like magic or a "super complex topic" to those who don't even understand the basic principles of how something works!

2. Huh? It's a "super complex topic" which you clearly don't understand and you even admit: "_I know I'm an amateur unqualified to make global statements of fact_". Bizarrely, knowing that you're unqualified "to make global statements of fact" doesn't seem to stop you from doing exactly that! Why is that, do like making yourself look foolish or are you just assuming that everyone here is similarly as ignorant of the basics and therefore won't recognise your "global statements of fact" are nonsense you've just made-up? In this specific example (which is just one of many), you've made a "global statement of fact" about what variables affect digital audio, a statement which impressively manages to completely contradict the whole point of what digital audio is and why it was invented in the first place! The actual fact is that the concept of digital audio was invented over 90 years ago for the specific purpose of eliminating the variables of environment, specific equipment and human biology.



GrussGott said:


> [1] Personally I don't expect anything to work flawlessly, but that's mostly because, as an engineer, *I've yet to experience "flawless" with anything, ever.*
> ... *My car has worked flawlessly* ... [1a] And I worked with commercial airplanes for a decade.
> [2] Yet that's not enough for me. I want more. and I can get more, so I modify it - not because of problems, but because I want more, i'm always searching for more performance, and I know I can get it. and I do.



1. Not only are you completely contradicting yourself (AGAIN!) but your also contradicting simple logic and one of the most proven and demonstrated facts in the whole of human history. That's an impressive feat for even the most ignorant and extremist of audiophiles! Firstly, the principle of digital working flawlessly was proven beyond any doubt mathematically over 70 years ago and secondly, it could hardly be a more demonstrated actual fact. For example, the latest generation of iPhones are apparently capable of about 5 trillion instructions per second. So, if only one in 5 trillion instructions (or the transmission of the digital data those instructions are acting upon) were flawed, the iPhone would crash on average about once per second. Are you really saying you've "yet to experience" an iPhone (other smartphone, computer or any other digital device) that didn't crash every few seconds? How on earth did the digital age come to be if no digital device could operate for more than a few seconds without crashing?
1a. A commercial airplane has what, countless thousands of cables totalling god knows how many kilometres length? If all those cables were operating "flawed", how would you ever even turn on the air conditioning, let alone actually get a commercial airliner off the ground? Are you saying that in a decade of working with commercial airplanes, you've "yet to experience" one that could actually fly?

2. And how do you modify a car to improve it's performance? Bolt on a turbo, remap the ECU, maybe change the exhaust OR, do you improve it's performance by changing say the (fully functioning) battery leads? It's relatively easy to stick a car on a dyno and measure it's performance, so presumably you can supply some objective evidence that changing any of the fully functioning cables in a car improves it's performance?



GrussGott said:


> [1] That's why I have nice cables (including USB) - cause they produce better sound quality in my setup.
> [2] Well Steve, I'm a big fan of experience being the best teacher, so here's what I can show you:



1. As a USB cable is Not carrying any audio how can it "produce better sound"?

2. You're joking right? Do you really not know what science is and why it was invented? Just a brief grade school recap: Thousands of years of personal experience led to all the dark age, medieval beliefs in witches, magic, the sun revolving around the earth, counter productive medical treatments and a whole host of other ridiculous beliefs and myths. Science was invented to try and eliminate those personal experiences/beliefs, to expand knowledge and get to the actual facts by far more objective methods. Sure, experience can be a very valuable commodity BUT ONLY if it's based on actual fact/science. If instead it ignores and contradicts the facts/science then it's the EXACT OPPOSITE of "being the best teacher"! Secondly, this is NOT the "What Grussgott is a big fan of" forum, nor is it the "Grussgott's experience" forum, this is the Sound Science forum. So unless "_what I can show you_" is the facts/science (or some compelling evidence which demonstrates the facts/science is wrong), then at best it's irrelevant and at worst it's wilful, ignorant trolling!

I've seen all kinds of utter nonsense posted by extremist audiophiles over the years but rarely have I seen quite so much obvious self contradiction and obvious contradiction of the most proven and demonstrated of facts.

G


----------



## castleofargh

when a cable creates a night and day improvement, I want to know first and foremost that it really happened outside the mind of the listener(objective reality and stuff). I want to know that it's an actual increase in fidelity, and not just a mess that the guy happens to enjoy subjectively. I want to know that the improvement isn't in fact that the original cable was damaged or really massively out of spec. and ideally, I'd like to know that the "improvement" is going to be transferable when using that cable on other computers and DACs(that's really the unlikely part of this all adventure TBH).
all those things are very much relevant in estimating the value of the "audiophile USB cable". so why are people making claims like they have already answered all those questions, but then when asked about them, it turns out that those questions didn't even come to the mind of the guy bragging about his cable, let alone trying to answer them.

most of us here are just amateur audiophiles like @GrussGott mentioned, and we certainly can't, or just don't want to go through a list of annoying tests. that's perfectly fine. so instead, you guys have a feeling that the sound is better on your system with the new USB cable. and that's it. first, good for you. second that's an anecdote about sighted impressions on a specific computer and DAC used under specific conditions. please when you tell us about it, describe things for what they are, not as if you just discovered the universal cure to low fidelity that has 100% success rate verified by all the guys at MIT and the top engineers at NASA for the last 20years.
remove all the posts that can't even follow that very obvious and simple request, and the topic is almost empty of claim or conflict.


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## bigshot (Nov 14, 2018)

GrussGott said:


> That's why I have nice cables (including USB) - cause they produce better sound quality in my setup.



How did you determine that? Measurements or controlled listening tests?

You posted an anecdotal story posted by a seller of cables on his retail website as proof. Is there any independent verification of this story to show that it isn't just sales pitch? If not, can you point to a controlled test that has been conducted by an independent group of people that came to the same results?


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## GrussGott

gregorio said:


> It's a "super complex topic" which you clearly don't understand and you even admit:



Well Greg, I'd put it this way: I'm wise enough on the topic to know nobody really knows.  We're all amateurs.  That doesn't mean we can't have great science discussions, but it does mean, if we're honest with ourselves and our egos, we'll never come to any solid conclusions because there aren't any possible from us.

For example, our USB cables use electricity, one of the 3 forces within the framework we call The Standard Model which theoretical scientists would tell us is derivative of quantum field theory.  The thing is, we know The Standard Model is wrong, just not how or where.  That means our understanding of electricity is wrong somehow, which means our ability to predict its behavior is wrong in some way - we're just not sure how, when, or where.  We can make good enough guesses to get the macros right, and usually keep from killing ourselves with it, but weird shiit is always happening.  Have you ever tried to design an electronics product?  If so, then you certainly know there's always some fresh new weird shiit! 

Anyway, all of that means it's not possible for us to provide definitive non-religious answers about electrical behavior, just good guesses and what's worked for us so far.


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## GrussGott (Nov 14, 2018)

bigshot said:


> How did you determine that? Measurements or controlled listening tests?
> 
> You posted an anecdotal story *posted by a seller of cables on his retail website as proof.* *Is there any independent verification of this story to show that it isn't just sales pitch? *If not, can you point to a controlled test that has been conducted by an independent group of people that came to the same results?



Given this is the science forum, and science is about explaining observed phenomena, my approach is to speculate based on electrical theory and digital signals processing.  I'm not convinced we've exhausted all equipment-based possibilities to explain the behavior, and, if you're curious, you can go back and read my posts about what those system-based explanations might be.

*I also don't believe any vendor like PS Audio *(who doesn't sell USB cables),* Schiit, AudioQuest, ZMF or any others that sell cables are doing so to defraud customers as you are suggesting.  *The notion these companies are lying, deceiving and/or intentionally misleading is tin-foil hat conspiracy at best and probably borders on slander.


----------



## Triode User

GrussGott said:


> probably borders on slander.



Libel because it is written.


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## PointyFox (Nov 15, 2018)

GrussGott said:


> Given this is the science forum, and science is about explaining observed phenomena, my approach is to speculate based on electrical theory and digital signals processing.  I'm not convinced we've exhausted all equipment-based possibilities to explain the behavior, and, if you're curious, you can go back and read my posts about what those system-based explanations might be.
> 
> *I also don't believe any vendor like PS Audio *(who doesn't sell USB cables),* Schiit, AudioQuest, ZMF or any others that sell cables are doing so to defraud customers as you are suggesting.  *The notion these companies are lying, deceiving and/or intentionally misleading is tin-foil hat conspiracy at best and probably borders on slander.



AQ does make claims and implies that "strand interactions", dielectric insulation effects, and metal grain boundaries introduce audible distortion which their USB wires solve, "nearly eliminating harshness and greatly increasing clarity".
I tried seeing if these were a thing and I couldn't find anything besides audio cable sales pitches.


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## gregorio

GrussGott said:


> [1] Well Greg, I'd put it this way: I'm wise enough on the topic to know nobody really knows...
> [2] For example, our USB cables use electricity, one of the 3 forces within the framework we call The Standard Model which theoretical scientists would tell us is derivative of quantum field theory. The thing is, we know The Standard Model is wrong, just not how or where. That means our understanding of electricity is wrong somehow, which means our ability to predict its behavior is wrong in some way - we're just not sure how, when, or where. We can make good enough guesses to get the macros right, and usually keep from killing ourselves with it, but weird shiit is always happening.
> [3] Have you ever tried to design an electronics product? If so, then you certainly know there's always some fresh new weird shiit!
> [4] Anyway, all of that means it's not possible for us to provide definitive non-religious answers about electrical behavior ...



1. We're not interesting in what way you would put it, in what you think you know or in how wise you think you are, this isn't the "what Grusscott thinks of himself" forum, it's the science forum! How many times?
2. Oh good, a long winded version of the old schoolboy fallacy: "Science doesn't know everything, therefore science doesn't know anything." What makes you think, here of all places, that employing such a schoolboy fallacy would make you appear anything other than foolish?
3. What new weird crap? Give us just one example of some weird new crap that affects an electric current in ways we can hear but can't measure, just one!
4. What all of that actually means is that it's apparently not possible that you know or understand any science later than about 200 years ago! Electrical behaviour was defined mathematically over 150 years ago, clearly you are ignorant of this fact, despite it being one of the most famous of all scientific facts. Again, this is the science forum, NOT the "Gusscott doesn't know anything, therefore no one does" forum!!



GrussGott said:


> [1] Given this is the science forum,
> [2] and science is about explaining observed phenomena,
> [3] my approach is to speculate based on electrical theory and digital signals processing.
> I'm not convinced we've exhausted all equipment-based possibilities to explain the behavior, and, if you're curious, you can go back and read my posts about what those system-based explanations might be.



1. What do you mean "given this is the science forum"? You're deliberately (or ignorantly) ignoring the science!

2. No it's not! Jezz, you've just demonstrated you don't even know what science is "about"! If you don't even know what science is, why are you even here?

3. If you don't even know what science is, let alone the specific science which defines electricity and digital audio then I suppose speculation is your only option. Not for us though and (yet) AGAIN, this is not the "Gusscott's Uniformed Speculation" forum, it's the SOUND SCIENCE forum!!!

G


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## Steve999 (Nov 15, 2018)

Triode User said:


> Libel because it is written.



If what was said or written were true that would be a complete defense. And if there was no merit to what you were saying you could face sanctions for a frivolous lawsuit against an innocuous internet poster. And if you were inducing people to spend money based on a deliberate misrepresentation of the facts that could form the basis of a countersuit for consumer fraud, or catch the attention a state or Federal attorney general. Are you ready to play hardball then?


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## castleofargh

GrussGott said:


> Well Greg, I'd put it this way: I'm wise enough on the topic to know nobody really knows.  We're all amateurs.  That doesn't mean we can't have great science discussions, but it does mean, if we're honest with ourselves and our egos, we'll never come to any solid conclusions because there aren't any possible from us.
> 
> For example, our USB cables use electricity, one of the 3 forces within the framework we call The Standard Model which theoretical scientists would tell us is derivative of quantum field theory.  The thing is, we know The Standard Model is wrong, just not how or where.  That means our understanding of electricity is wrong somehow, which means our ability to predict its behavior is wrong in some way - we're just not sure how, when, or where.  We can make good enough guesses to get the macros right, and usually keep from killing ourselves with it, but weird shiit is always happening.  Have you ever tried to design an electronics product?  If so, then you certainly know there's always some fresh new weird shiit!
> 
> Anyway, all of that means it's not possible for us to provide definitive non-religious answers about electrical behavior, just good guesses and what's worked for us so far.


sorry but that's nonsense. just throwing quantum theory into our everyday use of electricity and wires is like saying we don't know how to grow vegetables because we haven't gotten a full grasp of the quantum state of the atoms in the vegetable. you can say it if you like, but really you just sound weird.
here I believe you have to be careful about the difference between what you understand and what is universal knowledge available to mankind. I imagine that all electrical engineers have been tortured a few times with the game of simulating a wire as successive RLC components. hopefully nowadays teachers aren't dicks and they let students use some matlab program to do it all fast and clean.

of course you can always complain that it's only an approximation and that the result is only following the actual wire down to a µV or something and that's it's "dramatically" out of phase at whatever frequency. then you can declare that we don't know how things below µV impact our DAC, and once launched in that direction there really is nothing to stop you(aside from common sense). if you chose to go down the rabbit hole, it's all mystery and paranoia. maybe if I moved my cable one centimeter on the left, the resulting electrical properties would improve the sound? and what's fun is that it's actually possible, so long as you're ready to count any possible change of any magnitude as a relevant one. and when you got your wire and flexed it to straighten it up, that did change the electrical characteristics of the cable. hermagerd you just ruined your cable!!!! or maybe you could blame the guy who first deciding to roll it around something. if your limit is no limit, then everything is a drama.
 at the end of the day, you have to make a choice. live the life of an unstable paranoid person, or define your actual needs and simply ensure that your cable will keep the signal within those defined parameters. I've said it many times, but if your concern happens to be fidelity, then you should probably invest some time and a little money in measuring the output signal instead of worrying about highly technical stuff while at the same time testing cables with medieval techniques.
if your concern is audibility, you should bother setting up actual listening tests instead of listening with your eyes.
if your concern is what your guts tell you when you try a given cable. then you already know all you need to know. the one making you happy is the right one. sound may or may not have anything to do with it, but who cares if the one true target is being happy. I fully support this approach as being a valid one in audio. it just disqualifies people from claiming anything about the objective nature of the cable and the signal coming out of it. because subjective stuff aren't objective. the end. ^_^


----------



## Triode User

Steve999 said:


> If what was said was true that would be a complete defense. And if there was no merit to what you were saying you could face sanctions for a frivolous lawsuit against an innocuous internet poster. And if you were inducing people to spend money based on a deliberate misrepresentation of the facts that could form the basis of a countersuit for consumer fraud, or catch the attention of state of Federal attorney general. Are you ready to play hardball then?



Why are you addressing this to me? What do you mean, "Are you ready to play hardball then?" I only corrected the common libel/slander incorrect use of the words.


----------



## Whazzzup

Actually do dac makers, cable and USB makers, amplifier etc.. make any claims that they produce better sound than anyone else? I’d say let’s get the courts to sort out the audio industry. Let the gavels fly, but I think they covered themselves by only offering third party testimony and other non predictive measures to keep the smoke screen up.


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## Steve999

Triode User said:


> Why are you addressing this to me? What do you mean, "Are you ready to play hardball then?" I only corrected the common libel/slander incorrect use of the words.



Just throwing out some hypotheticals to extrapolate from your assertion and educate everyone a little bit. I won’t have a member of the trade making an off-hand comment to try to put a damper on the truth in this sub-forum. Next time think before you write.


----------



## Steve999

Whazzzup said:


> Actually do dac makers, cable and USB makers, amplifier etc.. make any claims that they produce better sound than anyone else? I’d say let’s get the courts to sort out the audio industry. Let the gavels fly, but I think they covered themselves by only offering third party testimony and other non predictive measures to keep the smoke screen up.



I think they just have much bigger fish to fry than these dudes. I don’t think their smokescreen is as good as they think it is.


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## Triode User

Steve999 said:


> Just throwing out some hypotheticals to extrapolate from your assertion and educate everyone a little bit. I won’t have a member of the trade making an off-hand comment to try to put a damper on the truth in this sub-forum. Next time think before you write.



I am sorry but you are entirely mistaken in your assumption that I was attempting to "put a damper on the truth in this sub-forum" and I would request that you withdraw that allegation. To quote you, "Next time think before you write."


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## gregorio

Whazzzup said:


> I’d say let’s get the courts to sort out the audio industry. Let the gavels fly, but I think they covered themselves by only offering third party testimony and other non predictive measures to keep the smoke screen up.



To be honest, the gavels need to fly first in the area of beauty/health/diet products. At least audiophile marketing is only spreading lies that cost the poor suckers their money, some of the diet/health/beauty products are downright physically dangerous! You're right though, in general they cover themselves, "we believe this is the best DAC" rather than "this is the best DAC" would leave you in court trying to disprove what someone believed. Unfortunately, we live in a society that instead of punishing liars, rewards the best ones with wealth and riches.

G


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## Steve999 (Nov 15, 2018)

Triode User said:


> I am sorry but you are entirely mistaken in your assumption that I was attempting to "put a damper on the truth in this sub-forum" and I would request that you withdraw that allegation. To quote you, "Next time think before you write."



Point A: I made no allegation, that was an opinion. In this country at least we are free to hold whatever opinion we like. My opinion was that as a member of the trade you were trying to squelch the truth. Maybe it was not intentional but that was the tenor of it, and you probably didn't think about what you were doing or how you were feeling. That's why I wrote for you to think before you write. As a member of the trade you have a particular and special status here.

Point B: If I am mistaken (only you would know for sure) I sincerely apologize and I would feel bad about that. I can't read your mind.

Point C: You have nothing to worry about from me except me calling BS if you piss me off _really badly_. Otherwise I'm inert.

Point D: I like to have fun here! I like to be silly! Maybe you could post something in the music thread! The other guys know a lot more than I do. I see nonsense here all the time and let it slide or even run with it. I could go around blasting it with dynamite even with my very limited knowledge but that's not my personality or my deal. I am not averse to having fun with people I disagree with. I _like_ people. If you want to shoot back at me that's your deal. That's how this place goes. I get offended very rarely but you offended me. We can have fun now if you would like, no problema.

@castleofargh WILL put me in check if I get out of hand. And I have done so. With silliness.


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## castleofargh

Steve999 said:


> Point A: I made no allegation, that was an opinion. In this country at least we are free to hold whatever opinion we like. My opinion was that as a member of the trade you were trying to squelch the truth. Maybe it was not intentional but that was the tenor of it, and you probably didn't think about what you were doing or how you were feeling. That's why I wrote for you to think before you write. As a member of the trade you have a particular and special status here.
> 
> Point B: If I am mistaken (only you would know for sure) I sincerely apologize and I would feel bad about that. I can't read your mind.
> 
> ...


I'd like to call up the lyrics from "Eye in the sky", both to discuss false accusations, and to remind everybody that as a modo, I am looking at you, and of course I can read your mind!


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## Steve999 (Nov 15, 2018)

castleofargh said:


> I'd like to call up the lyrics from "Eye in the sky", both to discuss false accusations, and to remind everybody that as a modo, I am looking at you, and of course I can read your mind!



Done! (With corrections by me after listening to the song, and a shrinking and colorizing of the font. Wow! I never appreciated the intensity of the lyrics before!)

Eye in the Sky
Alan Parsons
Songwriters: Alan Parsons / Eric Nor

Don't think sorry's easily said
Don't try turning tables instead
You've taken lots of chances before
But I'm not gonna give anymore
Don't ask me
That's how it goes
Cause part of me knows what you're thinkin'

Don't say words you're gonna regret
Don't let the fire rush to your head
I've heard the accusation before
And I ain't gonna take any more
Believe me
The sun in your eyes
Made some of the lies worth believing

I am the eye in the sky
Looking at you
I can read your mind
I am the maker of rules
Dealing with fools
I can cheat you blind

And I don't need to see any more
To know that
I can read your mind, I can read your mind
I can read your mind, I can read your mind

Don't leave false illusion behind
Don't cry, I ain't changing my mind
So find another fool like before
Cause I ain't gonna live anymore believing
Some of the lies while all of the signs are deceiving

I am the eye in the sky
Looking at you
I can read your mind
I am the maker of rules
Dealing with fools
I can cheat you blind

And I don't need to see any more
To know that
I can read your mind, I can read your mind
I can read your mind, I can read your mind

I am the eye in the sky
Looking at you
I can read your mind
I am the maker of rules
Dealing with fools
I can cheat you blind

And I don't need to see any more
To know that
I can read your mind, I can read your mind
I can read your mind, I can read your mind


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## Steve999 (Nov 15, 2018)

To Whom It May Concern:


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## Steve999 (Nov 15, 2018)

So, um, to stay on topic, I now attached to my computer here one outboard DAC going to a stereo and one outboard DAC going to some headphones. I found both of them lying around in some junk. I am actually very fond of both of them. I just hooked them up with two USB cables I dug up off the floor. I have no idea where I got the cables, and I truly don't care. _Really_. _I don't_. They probably came in a box with some gadget. So the answer to the topic of this thread, namely: Why do USB cables make such a difference, _might_ be, I dare say _might be, _something like, they don't make any audible difference if everything is even remotely okay, so the question is based on a false premise, and the rebuttal or support of that false premise generally speaking is the topic of this thread. Otherwise this whole thread _might_, I say _might_, have taken up _one or two posts_. Sorry if I am being, as @castleofargh might say, Captain Obvious, but I thought maybe I had steered this thread off course. Arm yourselves and resume!

I envision something like this:

Q: Why do USB cables make such a difference?

A: They don't make any audible difference if everything is even remotely okay. {Brief discussion}.


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## bigshot

GrussGott said:


> Given this is the science forum, and science is about explaining observed phenomena, my approach is to speculate based on electrical theory and digital signals processing.



So you’re saying that you’re saying there is a difference because of purely theoretical reasons and belief, but no actual evidence? A hypothesis is a great place to start, but it’s just a guess until you test it and start coming up with results that support it. I’d suggest that now that you have a theory, you should do a few controlled tests to see if it’s correct. Check back here once you’ve done that.


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## Redcarmoose

Going from drugstore HP USB cables to a $170 AudioQuest Carbon USB tomorrow night. I’ll report back any findings?


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## chef8489

Redcarmoose said:


> Going from drugstore HP USB cables to a $170 AudioQuest Carbon USB tomorrow night. I’ll report back any findings?


How do you plan on doing measurements? Or tests?


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## Redcarmoose (Nov 24, 2018)

chef8489 said:


> How do you plan on doing measurements? Or tests?


Highly subjective, inconclusive and non-scientific listening tests.

The only thing I have going for me is that I’m familiar with the sound as the system sits originally. The USB cable function is to go from a DAP docking station to a DAC/Amp. I was actually recommended this cable for the application from folks who have parallel set-ups, and report improvement. Truly I’m guessing for no improvement, but if there is a change then all’s good. It’s actually a fairly closed up system with not really any extra ways to get improved sound. The only next step would be the Kimber Axios cable after this USB is in place. The regular Kimber headphone cable added some improvement but no way am I spending 1K on a headphone cable, so this USB cable is the end of the line, short of getting some new IEMs.


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## GrussGott (Nov 24, 2018)

chef8489 said:


> How do you plan on doing measurements? Or tests?



As for measuring audio, seems like we'd first have to establish what "good" was by the numbers (after the macro measures of course such as distortion or whatever).  So, classic example, many listeners prefer phono over digital and we'd have to figure out how to measure for that, but even if we could, we get into the whole game of biology: even if we know what to measure, and have the capability to measure everything that establishes "excellent audio", how do we account for variance in human biology and preference?  That is, how do we say that X measures mean something is happening and Bob will love it?  After all, we know it's not just the bits, but the timing (and with USB audio of course it's guaranteed bandwidth with no error correction)

This gets us the human factors.  For any test to be complete, here would be a few things that we'd have to control for:

*(1.) Human biology / genetics*
Some around the World hear "the hum" - I first learned about it because on a trip to the Gold Coast in Vancouver I heard it but nobody else did so I looked it up.  However, there are more mundane things like identifying live music such as live guitar, even when the guitar is played through an amp.  We have a park 2 blocks away and most people can tell you live music vs recorded & played through the same speakers and amps.  This is probably due to certain frequency harmonics, echos, and other queues that we don't know we know and therefore can't  and don't measure.  In any event, we'd have test 1000s of people and identify classes of "hearers" of which there'd probably be a lot (e.g., can hear high freqs, low freqs, can ID live music, can differentiate background sounds, etc etc).

*(2.) Listening skill*
This would be easier, but we'd have to ensure that within each group type we were testing, they were trained listeners.  Once I toured an expensive perfume factory in France and met the head "smeller" - she didn't know if she had a better sense of smell but she was trained to identify 1000s of aromas and no matter what I mixed up she could instantly identify everything I tossed in there.  So we'd also need to ensure we controlled for level of skill, and ideally the listeners would be musically trained so they'd know what to listen for and what they were hearing.

*(3.) Operating environment / location*
Anyone that's done precise engineering with electronics and/or signals knows that different geographies and EMI environments affect electronics differently.  Medicine, as an example, controls for this.

Anyway, those are just a few of the factors, none of which have even been done even a single time, and even if they were could they guarantee Bob would or wouldn't hear something we didn't control for?

*Net-net: *formal audio testing is worthless to us, thus all we can do is listen blind and pick.


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## chef8489

GrussGott said:


> As for measuring audio, seems like we'd first have to establish what "good" was by the numbers (after the macro measures of course such as distortion or whatever).  So, classic example, many listeners prefer phono over digital and we'd have to figure out how to measure for that, but even if we could, we get into the whole game of biology: even if we know what to measure, and have the capability to measure everything that establishes "excellent audio", how do we account for variance in human biology and preference?  That is, how do we say that X measures mean something is happening and Bob will love it?  After all, we know it's not just the bits, but the timing (and with USB audio of course it's guaranteed bandwidth with no error correction)
> 
> This gets us the human factors.  For any test to be complete, here would be a few things that we'd have to control for:
> 
> ...


Well first off I wanted to know if there would be measurements as if there is actual a sound change there will be a measurable change. So there will ba an a/b comparason on what the cable achieves. Second would like to know if he is swapping the cables and knows which is which, or someone else is and they know, or if the cables are covered and someone else is swapping the cables and it is a double blind test. That was what I was interested in on how the test would be set up and how or if he planned on eliminating the placebo effect.


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## Redcarmoose (Nov 24, 2018)

That’s what is so great about graphs of a frequency response of a headphone or IEM. Normally a headphone hits the market and folks use it. Due to the detail and OCD around here, folks will at times try to describe what they are hearing. So observation could in a way be considered the first level of testing.

Let’s say the headphone has a slight response flaw. Folks many times will notice that flaw. If people have heard a recording over and over again they can get familiar with how the music sounds. I’m not saying they heard the reproduction in a perfect way. But maybe due to hearing it on a multitude of systems and over a large time frame they get a generalized idea of what they think is the correct sound of the music.

After they hear the playback on the new headphones this sonic error can many times be noticed. Another way is if they are a musician and daily surrounded by accurate renditions of an instrument tone; they just start to know what’s right.

Later someone measures the headphone and everyone gets to note where the issues are. Most of the time before the measurement it’s all just a guess, depending on the severity. After reliable measuring is done a reality is finally noted.

Still this same method seems to cause issues at Head-Fi as almost rarely does the quality of the measurement get questioned. If a bad graph on a new headphone gets posted, folks actually start to hear what the graph shows. After the suggested rumor of bad sound gets talked about, rarely does the headphone ever redeem itself. People simply hear what they are told to hear. 

Cables on the other hand are usually more difficult to test. IEM cables can show a different resistance which can affect sound character, but most aspects of cables offer a percentage of improvement which stays beyond the limits of testing with a machine. The problems with subjective listening tests start because the added placebo effect. Take something like an expensive cable..........it’s suggested to improve audio, when infact the different results are none.


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## Redcarmoose

But tonight I will have a friend switch or not switch USB cables while I have my back to the system; to find out if I can hear the new USB cable. Obviously if I view the new USB cable it will sound better. Same as red cars with mag wheels seem to go faster.


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## GrussGott

Redcarmoose said:


> Take something like an expensive cable..........it’s suggested to improve audio, when infact the different results are none.



Great summary - when it comes to testing I'm a big fan of atomic bob, as he seems to have both the technical skill and listening skill to provide useful feedback; nevertheless all audio testing and its applicability to us as listeners is limited by the factors I listed above.  I've worked in healthcare for 15 years and if testing was reliable enough to predict outcomes a lot of doctors would be out of jobs - basically the testing helps us with gross motions, and then seems to give us directional indications as we get more granular (e.g., what treatment will be truly therapeutic?  BTW, placebo, in small ways, *is* therapeutic)

Back to audio and USB, atomic bob has done some great testing of USB cables (google "USB cable shield resistance technical measurements"), and he also has a great series on audio component synergy (google "System Synergy - Special Sound).  Given his expertise, it's interesting to note the cables he uses: good but not fancy cables.  Does this mean cable impact on sound quality is impossible?  No, but it means that, directionally, he doesn't seem to think that cables are a key component of an audio system.

Thus advice to folks to probably inline with that testing: components first, cables second.


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## chef8489

Well the whole point is USB cable doesn't actually carry any audio. It Carrie's digital data that is then turned into sound by the dac.If there is a difference in the data carried by said cable it is measurable.


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## bigshot

A simple checksum is all that is needed... and of course that has been done and isn't an issue so no-one bothers to question it any more. If a USB cable is introducing errors, you are going to know it. It won't be subtle at all. Digital doesn't have veils, it has glitches.


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## GrussGott (Nov 24, 2018)

chef8489 said:


> Well the whole point is *USB cable doesn't actually carry any audio*. It Carrie's digital data that is then turned into sound by the dac.If there is a difference in the data carried by said cable it is measurable.



No cables carry audio - they all carry electrical (or light) representations of audio; the difference is that USB carries an electrical encoding of "on" or "off" voltages which is then converted to varying voltage in the DAC, which then sends the newly encoded electrical representation of audio  it to the amp for amplification, which then sends it to the transducers which convert the electrical representations to mechanical motion, which moves air which creates the sound.

So, yeah, no cables carry audio, just varying voltages of one sort or another which must be decoded (and if something messes with _any _of those voltages in transit, it can cause audible errors when decoded)


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## chef8489

Yes they but the voltage can vary such a wide range and still represent a 1 or a 0 and still be perfect for the dac to read. It either reads the 1 or 0 or it doesnt.


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## bigshot

A simple checksum test at the end of the cable will verify if it's working properly. I don't think you need to spend more than a few dollars to get a cable that does that correctly.


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## GrussGott (Nov 24, 2018)

chef8489 said:


> Yes they but the voltage can vary such a wide range and still represent a 1 or a 0 and still be perfect for the dac to read. It either reads the 1 or 0 or it doesnt.


And, since the usb audio spec specifies a live stream unlike a thumb drive transmission which has error checking, the dac also gets the errors (reads a sent 1 as a 0 or vice versa) which it can't reask for due to the live stream... And there's the timing: it's not just if the bits arrive, but when.  If those bits arrive early or late, more problems.

So, yeah, if you mess with live-stream encoded voltages in transit, no matter where, it's going to have an impact.


----------



## chef8489

GrussGott said:


> And, since the usb audio spec specifies a live stream unlike a thumb drive transmission which has error checking, the dac also gets the errors (reads a sent 1 as a 0 or vice versa) which it can't reask for due to the live stream... And there's the timing: it's not just if the bits arrive, but when.  If those bits arrive early or late, more problems.
> 
> So, yeah, if you mess with live-stream encoded voltages in transit, no matter where, it's going to have an impact.


Well there is a buffer, but yes you can have errors, but if the cable is in spec and not faulty


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## GrussGott

chef8489 said:


> Well there is a buffer, but yes you can have errors, but if the cable is in spec and not faulty



Right, so it's quite possible a USB cable will have an impact on sound quality, just not highly probable for most ears, most systems. (depends on ears, equipment, environment - the 3 Es of good audio!)

So for any noobs reading, invest in a USB cable last and do so cautiously and with a reputable dealer who'll let you return the cable for a full refund if you don't hear a difference.


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## bigshot (Nov 24, 2018)

How is it quite possible? We've explained the mechanics to you over and over in this thread and you still keep clinging to the idea that fancier USB cables sound better. They don't. If they lag, the buffer will catch it. If they produce errors, the sound will glitch in very audible ways. I've never experienced a USB cable that sounded slightly better than another in controlled tests. Have you? Either they work or they short out and don't. I think you've never done any controlled listening tests and you're basing this on your preconceived ideas or expectation bias. You might want to apply some controls to your listening tests to eliminate this possibility. Blind testing will help a lot.

USB cables are tested to make sure they perform flawlessly. Passing audio signals across is an easy task compared to passing video. I have USB hard drives that play HD video with surround audio perfectly. They can certainly play a CD without errors.

USB cables either work or they don't.


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## Glmoneydawg

GrussGott said:


> Right, so it's quite possible a USB cable will have an impact on sound quality, just not highly probable for most ears, most systems. (depends on ears, equipment, environment - the 3 Es of good audio!)
> 
> So for any noobs reading, invest in a USB cable last and do so cautiously and with a reputable dealer who'll let you return the cable for a full refund if you don't hear a difference.


Not really my forte but....digital issues(few and far between )are going to be far more obvious than subtle changes in"sound quality "


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## GrussGott (Nov 24, 2018)

Glmoneydawg said:


> Not really my forte but....digital issues(few and far between )are going to be far more obvious than subtle changes in"sound quality "



For gross errors of missing data, yes, but for other errors not necessarily as the DAC is simply translating one set of voltages to another live so both amplitude and timing must be correct:







A red book CD encodes samples as a 16-bit number, meaning 65,536 different steps (see above), so, say, 1100010000011000 is amplitude step 50,200.  If transmission errors degrade the signal the DAC might decode the sample as 1100011000011000, which is the 50,712 step, or as 1000011000011000 which is the 34,328 step, and then passes that wrong value through for amplification.

I believe it takes good ears, good equipment, and attentive listening to hear this because noise and jitter cause errors randomly ...

and there are really only two possibilities: either it's audible which is why so many experienced audiophiles hear differences, or it's mass delusion that's so powerful, entire businesses can offer 60 day 100% money-back guarantee trials of their cables and stay in business all due to so many dummies.  (Hint: if you think everyone else is the dummy, you're the dummy)

*The reason USB Cables are so controversial is because of extremists:*

* On one side, "SQ impact is possible not really probable depending on the 3 Es" gets translated to "impossible therefore mass hallucination"
* On the other side "possible not probable" gets translated to "it's just like tube rolling!"

In any event, the errors happen this way:






And the DAC translation table up to 24 bits looks like this (you can see the voltages get pretty small!):


----------



## bigshot

Answer my question GrussGott. Why wouldn't a simple checksum give you the answer whether a USB cable works without all the charts and diagrams? I've suggested this several times now.


----------



## sonitus mirus

chef8489 said:


> How do you plan on doing measurements? Or tests?


He already did his testing, it is in his comment. $170 is his review of the product.


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## chef8489

sonitus mirus said:


> He already did his testing, it is in his comment. $170 is his review of the product.


You make no sense. The question was in before he did any testing.


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## Redcarmoose (Nov 25, 2018)

I have not done testing as of yet. Tomorrow. But the test will be a simple blind test, having my back turned and asking a regular cable be put in, then the Carbon USB. I’m not expecting much, so we will see. As long as both cables function with-in specification for USB, there is probibly no electrical methodology for test. I’m simply curious if the same song is played at the same volume level, that I will be able to subjectively discern between the two. Of course if I cannot....... well then I guess I’ll be left with a nice looking cable in the end?


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## Steve999

So what is this null hypothesis in this thread? In your test?


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## Redcarmoose (Nov 25, 2018)

My commonly accepted fact is there should be no differences. Even though I have been told by others that there would be a difference. Prior to this test I obtained a 10 foot long USB cable and noticed there was absolutely no difference in use from a regular USB cable. I also never have heard a difference between any USB cable I have tried in a visual changeout test.

It’s simply a hope that there could be a difference. And in my situation there is no option for returning the cable for a refund. But I’m pretty much at the very end of any upgrades. So you could call this simple curiosity at hand.

The cables will actually be swapped out randomly so I will not know which cable is being used.


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## Steve999

Redcarmoose said:


> My commonly accepted fact is there should be no differences. Even though I have been told by others that there would be a difference. Prior to this test I obtained a 10 foot long USB cable and noticed there was absolutely no difference in use from a regular USB cable. I also never have heard a difference between any USB cable I have tried in a visual changeout test.
> 
> It’s simply a hope that there could be a difference. And in my situation there is no option for returning the cable for a refund. But I’m pretty much at the very end of any upgrades. So you could call this simple curiosity at hand.
> 
> The cables will actually be swapped out randomly so I will not know which cable is being used.



Cool. So it sounds like the alternative hypothesis is that you will be able to hear a difference, but you are not optimistic, but you are doing the best you can to use sound methods and keep an open mind.


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## GrussGott (Nov 25, 2018)

Redcarmoose said:


> I have not done testing as of yet. Tomorrow. But the test will be a simple blind test, having my back turned and asking a regular cable be put in, then the Carbon USB. I’m not expecting much, so we will see. As long as both cables function with-in specification for USB, there is probibly no electrical methodology for test. I’m simply curious if the same song is played at the same volume level, that I will be able to subjectively discern between the two. Of course if I cannot....... well then I guess I’ll be left with a nice looking cable in the end?



That's basically exactly what I did, and I controlled the music, playing the same section of music I'm familiar with 3 times with the swap happening behind me (or no swap!).  Then I kept notes between 1-2 and 2-3, both on if I heard a difference and, if so, what, and then a guess if the cable was more expensive or not, and between a bunch of different cables.  I used a freebie that came with my printer, a mediabridge ($5), two pangea cables (the $30 one and the XL), and a slew of AQ cables  (forest, carbon, coffee, diamond), with the cables being switched mostly randomly, considering a >=70% pick rate success.

After a bunch of trials I couldn't tell the difference between the printer cable up to the low priced pangea, or between the carbon - diamond; however I was consistently picking the XL over the lower priced cables and the carbon over anything below it.  I also tried some different DACs this way, but that's another story (spoiler alert: the Mojo lost, the Schiit DACs won).

I'll likely upgrade to a high-end DAC this next year, and am *waiting on Schiit as they're the first(?) DAC manufacturer to develop their own USB implementation* (as certified by USB.org they've said: *"licensed USB special interest group" *- 24min mark, *"develop our own [USB] interface ... for our multibit DACs"*, "issue our own USB product codes" *"decouples us from XMOS ... as no one really understands what the hell XMOS, C-Media are really doing ..."*) which will free them from using off-the-shelf USB chips, and possibly from the USB audio spec, I don't know ... and if that's all true then it could very well mean that we'd need only an in-spec USB cable as they could use some type of new USB transfer method / mode, new drivers, or who knows.  If so, then the Yggdrasil will be in the basket!

One last point to add FWIW, as I've said my 2 cents is that digital cables can't roll sound as noise and jitter cause some amount of random errors depending on ears, equipment, environment; however, how we hear and enjoy music is complicated and not well understood (resonances, harmonies, undertones, etc).  Many times when I picked the better cable I had noted background sounds were louder / more apparent and this happened consistently ... I have no idea what that means, but I do listen to a lot of jazz and I find the theory around "Giant Steps" fascinating and maybe a clue to what's going on (theory starts around 2 min in):


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## bigshot (Nov 25, 2018)

The difference must have been huge if you had a several second delay between swapping the cables. Why not just do A/B switching? I guess you'd need a USB switcher that way. How many times did you do the test? What were your statistics? Could you tell 100% of the time? What frequencies appeared to be different? Was there audible artifacting in the cable that sounded different?

If one cable stood out from the rest, that is probably the one that I would suspect was causing errors. It's not likely that several cables would all exhibit error in the exact same ways. I'm not familiar with the brands of cables your mentioning. Could you link to the cable you say sounded different than the rest? Have you checked it to make sure it's passing the data correctly? For instance, use it to do a data transfer between hard drives and see if it errors or takes longer than a regular cable. One last question... do you know if your DAC has a cache? I would imagine it would, but perhaps there are strange audiophile ones that forgo the buffer for some strange reason.

You've identified something unusual here. The next step is to figure out why the one cable is different. If the difference is as great as you say, it should be clearly measurable, probably as massive errors.


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## Steve999 (Nov 25, 2018)

GrussGott said:


> That's basically exactly what I did, and I controlled the music, playing the same section of music I'm familiar with 3 times with the swap happening behind me (or no swap!).  Then I kept notes between 1-2 and 2-3, both on if I heard a difference and, if so, what, and then a guess if the cable was more expensive or not, and between a bunch of different cables.  I used a freebie that came with my printer, a mediabridge ($5), two pangea cables (the $30 one and the XL), and a slew of AQ cables  (forest, carbon, coffee, diamond), with the cables being switched mostly randomly, considering a >=70% pick rate success.
> 
> After a bunch of trials I couldn't tell the difference between the printer cable up to the low priced pangea, or between the carbon - diamond; however I was consistently picking the XL over the lower priced cables and the carbon over anything below it.  I also tried some different DACs this way, but that's another story (spoiler alert: the Mojo lost, the Schiit DACs won).
> 
> ...




Watched John Coltrane video. Cool. This isn't the Sound Science music thread (please post there, I love jazz!) so I'll keep it short. It seems as though Giant Steps was an extremely creative and demanding abstraction. I didn't hear Tommy Flanagan having the same troubles the other guys were talking about. John Coltrane was ripping off torrents of eighth notes at a breakneck pace and it was his song, I'm sure he had practiced it. Tommy Flanagan chose to phrase differently. He got a short solo and was not well-miked in my view and if he would have just continued on with a torrent of eighth notes as John Coltrane did it would not have been a very creative act on his part. He just chose to phrase more conventionally I think. He even got in a nice chord solo at the end to bring Coltrane back in. He knew who the star of the show was and what he was witnessing, I would venture to guess. Coltrane's solo seems to be in eighth notes--the tempo is flying by so fast it seems like it must be sixteenth notes but it sounds like eighth notes at a breakneck pace to me. As I've been listening to jazz for 40-plus years Giant Steps is somewhat of a cliche to me so ironically I probably haven't listened to it enough. But I did just give a close listen on Spotify, and yes it is a work of art, a very deeply complex and challenging and highly patterned musical abstraction.

Now as far as audio goes, if you want to get the benefit of the kinds of harmonics they were talking about, you want a really nice set of speakers and to be listening to a modern recording (I'd ballpark 1977 onwards) of high quality.  I don't like the images they conveyed. It's not an illusion like Escher. It's not like driving down obscure alley-ways. It's not like a color wheel. It's not like speaking in different languages--it's the same language, even bordering on monotonous in some ways (so shoot me), but in rapidly modulating keys. The language is just transposed or you might say the key modulated so that the root (the note you feel like you want to get back to) is on different pitches. It's a beautifully symmetrical abstraction. An abstraction. SOMETIMES SOMETHING IS JUST AN ABSTRACTION!!!! In the pop song where they were pointing out the modulations they were just modulating up a half step each time which I often consider just a cheap amateurish trick to gin up excitement. It's nothing remotely as complex as what Coltrane was doing. I got back to the music again didn't I.

I think Hendrix's Hey Joe uses the circle of fourths. Fourths are inversions of fifths. You get a similar type of deal going on. But this is a case where what Coltrane was doing was just on the level of historical art and Hey Joe doesn't really get you that far.

Well back to audio. Those harmonics are not "subliminal" as is stated in the video. They're not trying to sell you cokes and popcorn with hidden sonic images. They really happen and they're not spooking your unconscious. It's just how the instruments work, as Leonard Bernstein showed you, and speakers with a nice flat frequency response and and a modern recording will let you enjoy those types of nuances in the music. Sorry to go off on a tangent everyone. I didn't keep it short did I. Oh well. Back to your regularly scheduled program.


----------



## Zworks

The price somewhat let you feel there must be an improvement. But I just bought some cables and make a simple blind test.


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## Redcarmoose (Nov 26, 2018)

bigshot said:


> The difference must have been huge if you had a several second delay between swapping the cables. Why not just do A/B switching? I guess you'd need a USB switcher that way. How many times did you do the test? What were your statistics? Could you tell 100% of the time? What frequencies appeared to be different? Was there audible artifacting in the cable that sounded different?
> 
> If one cable stood out from the rest, that is probably the one that I would suspect was causing errors. It's not likely that several cables would all exhibit error in the exact same ways. I'm not familiar with the brands of cables your mentioning. Could you link to the cable you say sounded different than the rest? Have you checked it to make sure it's passing the data correctly? For instance, use it to do a data transfer between hard drives and see if it errors or takes longer than a regular cable. One last question... do you know if your DAC has a cache? I would imagine it would, but perhaps there are strange audiophile ones that forgo the buffer for some strange reason.
> 
> You've identified something unusual here. The next step is to figure out why the one cable is different. If the difference is as great as you say, it should be clearly measurable, probably as massive errors.





Zworks said:


> The price somewhat let you feel there must be an improvement. But I just bought some cables and make a simple blind test.



That would be true if you were visualizing the test. He had a hand full of cables and they were randomly put in place. He had control over the music so he was able to consistently go back to the same section. He had a 70% success rate hearing the more pricy USB cable and could even distinguish mid level from high end.

This is what he wrote in quotes... Bigshot:

I will put some links in to the cables in an edit to this post.

His findings:
“After a bunch of trials I couldn't tell the difference between the printer cable up to the low priced pangea, or between the carbon - diamond; however I was consistently picking the XL over the lower priced cables and the carbon over anything below it. I also tried some different DACs this way, but that's another story (spoiler alert: the Mojo lost, the Schiit DACs won).”


His methodology and findings:
“That's basically exactly what I did, and I controlled the music, playing the same section of music I'm familiar with 3 times with the swap happening behind me (or no swap!). Then I kept notes between 1-2 and 2-3, both on if I heard a difference and, if so, what, and then a guess if the cable was more expensive or not, and between a bunch of different cables. I used a freebie that came with my printer, a mediabridge ($5), two pangea cables (the $30 one and the XL), and a slew of AQ cables (forest, carbon, coffee, diamond), with the cables being switched mostly randomly, considering a >=70% pick rate success.”

To summarize Bigshot, he was (70% on average) able to spot the XL cable above the cheap printer cables. He was able to always identify the AQ Carbon and AQ Diamond above everything below them at a 70% success rate.

He is also basicly saying the he could not distinguish between the Carbon and Diamond or the Coffee? If I read that right?

The question is what did he keep! Lol

The cables he used:

AQ Diamond $549
AQ Coffee    $279
AQ Carbon $165
AQ Forrest     $35
XL Panga       $79
$30 Panga
$5 Mediabridge
Free Printer Cable


Links:

https://www.audioquest.com/cables/digital-cables/usb-a-to-b/diamond


Of course SS getting ahold of AQ “scientific sales hyperbole” could infact cause quite the blow-out here. 


https://www.mediabridgeproducts.com/product/usb-2-0-a-male-to-b-male-cable-high-speed-10-feet/

https://www.audioadvisor.com/mobile/prodinfo.asp?number=PGUSBXL

https://www.amazon.com/Pangea-Audio-cable-solid-silver/dp/B005AUJ3SA


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## bigshot (Nov 26, 2018)

I'm looking for the USB cable that is the easiest to identify as sounding clearly different than the rest. Could you please break it down to that for me? Which one was most unique and easiest to spot? Were there several that all sounded different from each other? And was he able to spot specific cables and name them by sound alone? Which ones were those? I'm interested in the totally unique sounding cables.

A couple more questions... Does copying a sound file across from drive to drive result in a difference in sound too? Or is it only when it's played through a DAC? How many DACs or DAPs were used in this test? Did the odds of picking the specific cable change with different DACs?


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## Redcarmoose (Nov 26, 2018)

bigshot said:


> I'm looking for the USB cable that is the easiest to identify as sounding clearly different than the rest. Could you please break it down to that for me? Which one was most unique and easiest to spot? Were there several that all sounded different from each other? And was he able to spot specific cables and name them by sound alone? Which ones were those? I'm interested in the totally unique sounding cables.
> 
> A couple more questions... Does copying a sound file across from drive to drive result in a difference in sound too? Or is it only when it's played through a DAC? How many DACs or DAPs were used in this test? Did the odds of picking the specific cable change with different DACs?



Your actually convoluting this whole test of his and asking him to jump through uneeded hoops here. Read it as it states.......he got a handful of cables and did a blind test in a controlled environment. He charted his progress and had a outcome of being 70% correct.

Then because someone finished a personal test and came up with answers which were satisfactory for themselves, you berate the test with childish questions simply because their views don’t concur with your own. You want him to continue to test.......... laughingly.....because he is all done. With his reported outcome he has simply suggested as a reality for himself, and others to possibly learn something from; as none of us know everything but only a little. Interestingly it’s the same nihilistic audio jargon that has posted all DACs sound the same; now asking if he used a different DAC for each cable; please, of course he used the same equipment?

Your asking for one cable that’s easy to identify yet he showed he could not only do that but distinguish whole groups in a hierarchy. Your asking if several cables sounded different? You can’t simply comprehend what simply the outcome was which he wrote? They all sounded different in groups just as he documented. The groups he could not differentiate from one another he clearly lists. Your going to need to come up with better than normal nonsense arguments here........or maybe not.


You didn’t read simply what he wrote? It’s fairly straight forward.
There were several which all sounded different, which he was able to place in groups and identify from each other.

No, he wasn’t able to name each cable specifically, but was able to identify them in quality groups. Did you simply read what he wrote, or not?


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## bigshot (Nov 26, 2018)

I'm not trying to cause trouble. I'm just looking for a cable that sounds clearly different from every other cable. I'd like to try to get ahold of it and figure out what makes it sound unique. It appears that it would be one of the specialty brand cables. It should be simple to answer. We'll let him answer if you can't.


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## Redcarmoose (Nov 26, 2018)

bigshot said:


> I'm not trying to cause trouble. I'm just looking for a cable that sounds clearly different from every other cable. It should be simple to answer. We'll let him do it if you can't.



He clearly stated the top three he could not but as a group the top three could be differentiated from the middle group, and the middle group could be differentiated from the bottom group. Thus the total bottom group could be differentiated again from the total top group.

Still this is his personal findings, he clearly lists, as the post earlier stated there are more variables like equipment used, the listers ears and on and on. So it’s an individual conclusion due to the emence variables of subjective perception; and of course the many variables introduced by the tonal and detail responce of various audio equipment and their inherent tone. And while that’s maybe not the most scientific, it is what it is.

Each person needs to find out for themselves as there is no blanket application answer. Though small if the differences are truly there and worthwhile then.............if it can offer audio improvements to those willing to take the risk, and effort.

The reason my tests are not posted is I was trying to keep all things equal and running in (burning-in) the new USB cable so it would be in closer condition to the used USB cables.

My test will include:

Grey drugstore USB
10 foot drugstore HP USB
Normal HP USB
AQ Carbon USB


All placed in or not switched in random order. With maybe 20 blind listening tests documented if I could infact hear the expensive USB cable.

Obviously it does sound better in sighted tests, and I feel sighted tests are needed as if there is truly a sound signature improvement it would be beneficial if that personality could be known.


----------



## bigshot

So in other words, there are three different sound signatures with multiple cables with the exact same signature in each of the three types? That is very strange. Can the sound signatures be grouped by manufacturer? I can see how a brand might want to have a "house sound". I'm not sure how that would be accomplished with USB cables though.

It would be good to do data transfer tests with all of them to see which ones aren't performing properly. The odds are that one of the three groups is audibly transparent and the other two are colored. The only way to know which is which is to check transfer speed and do some checksums to detect errors.


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## Redcarmoose

bigshot said:


> So in other words, there are three different sound signatures with multiple cables with the exact same signature in each of the three types? That is very strange. Can the sound signatures be grouped by manufacturer? I can see how a brand might want to have a "house sound". I'm not sure how that would be accomplished with USB cables though.
> 
> It would be good to do data transfer tests with all of them to see which ones aren't performing properly. The odds are that one of the three groups is audibly transparent and the other two are colored. The only way to know which is which is to check transfer speed and do some checksums to detect errors.




But........    but...........but........you have stated endlessly that it’s data, only data being transferred. This has been your motto for years?

So how can the data be colored by the cable.

And let’s not go years and years back but only a page where you state that  either it works or it does not.


These are your own words.......bigshot, not mine.


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## Redcarmoose

bigshot said:


> So in other words, there are three different sound signatures with multiple cables with the exact same signature in each of the three types? That is very strange. Can the sound signatures be grouped by manufacturer? I can see how a brand might want to have a "house sound". I'm not sure how that would be accomplished with USB cables though.
> 
> It would be good to do data transfer tests with all of them to see which ones aren't performing properly. The odds are that one of the three groups is audibly transparent and the other two are colored. The only way to know which is which is to check transfer speed and do some checksums to detect errors.



Rereading your second section here I have to agree, if there truly was a way for manufacturers to tweak a USB cable to put out a different responce it would be gold. 

That’s all the IEM cable world is, fine tuning cables to fit the desired responce. I don’t want to list my sound signature ideas yet as they are visually done, but if a USB cable could color sound it would be marketable.


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## bigshot (Nov 26, 2018)

He says he applied controls to his test, so I am taking his test at his word, even though it makes absolutely no sense from a technical point of view. I would like to verify his results and find out why his test is showing three groups of coloration when it should be one group that all sound the same and a bunch of different colors on the ones that sound different. The easiest way to do that is to look for the most unique and easily identified cable first, because that is likely to be the most colored. We have people here who are set up to do controlled listening tests that I'm sure would be happy to help verify his results. All we really need to start is two cables that sound clearly different. If he is able to run data transfer tests on it that would  be great. If he isn't set up to do that, I'm sure someone here in the group would volunteer to help out with that too.

When you have an unusual result in a controlled test, the next step is to try to verify it by independently repeating the results. Once you've done that, you try to track down the source of the unusual behavior through measurements. That is what I'm trying to do here. I'm not assuming that a difference is either good or bad for the sound. That would be a totally different kind of test, and we can do that too once we figure out what is going on. First things first... we need to verify that two cables sound different. That just takes two cables and an independent person set up to do a controlled listening test. This group is full of candidates for that.


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## Redcarmoose

bigshot said:


> So in other words, there are three different sound signatures with multiple cables with the exact same signature in each of the three types? That is very strange. Can the sound signatures be grouped by manufacturer? I can see how a brand might want to have a "house sound". I'm not sure how that would be accomplished with USB cables though.
> 
> It would be good to do data transfer tests with all of them to see which ones aren't performing properly. The odds are that one of the three groups is audibly transparent and the other two are colored. The only way to know which is which is to check transfer speed and do some checksums to detect errors.



I’m not sure if he attributed qualities other than what we would consider higher grade audio; to each of the groups. 

It is interesting if someday USB cables would be described along the lines of analog cables. I mean they do describe digital cables like SPDIF that way in high-brow stereo circles.


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## bigshot (Nov 26, 2018)

AI don't care about higher grade audio at this point. That is a subjective evaluation. I want to verify and identify the objective difference first. He says that he had between 70% and 100% accuracy identifying three different sounds. All I need is two that sound clearly different. That should be simple. 

There's no point going to the trouble of describing subjective impressions of differences until you know for sure the differences exist and what causes them. That is the huge problem with the way people approach these things. They start out with a subjective impression, then they come up with a theory that assumes it's true, then they start cherry picking data to fit their theory. That is bass ackwards. You have to start out by dead to rights nailing down that there actually IS a difference before you start thinking up reasons why it exists.


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## Redcarmoose

bigshot said:


> He says he applied controls to his test, so I am taking his test at his word, even though it makes absolutely no sense from a technical point of view. I would like to verify his results and find out why his test is showing three groups of coloration when it should be one group that all sound the same and a bunch of different colors on the ones that sound different. The easiest way to do that is to look for the most unique and easily identified cable first, because that is likely to be the most colored. If he is able to run data transfer tests on it that would  be great. If he isn't set up to do that, I'm sure someone here in the group would volunteer to help out. We also have people here who are set up to do controlled listening tests that I'm sure would be happy to help verify his results. All we really need to start is two cables that sound clearly different.
> 
> When you have an unusual result in a controlled test, the next step is to try to verify it and once you've done that, you try to track down the source of the unusual behavior through measurements. That is what I'm trying to do here. I'm not assuming that a difference is either good or bad for the sound. That would be a totally different kind of test, and we can do that too once we figure out what is going on. First things first... we need to verify that two cables sound different. That just takes two cables and an independent person set up to do a controlled listening test. This group is full of candidates for that.



Yes, but haven’t you always said either USB cables work or they do not. 

And I’m not playing dumb here, I seriously don’t have a clue, that’s why I’m here. 

But I agree if there is tone being changed, how or why, and is it better or worse. 

If you read the claims by the manufactures they state about outside radio wave interference and it goes literally on and on.......and the more the cable the more on and on it goes.lol


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## Redcarmoose

bigshot said:


> AI don't care about higher grade audio at this point. That is a subjective evaluation. I want to verify and identify the objective difference first. He says that he had between 70% and 100% accuracy identifying three different sounds. All I need is two that sound clearly different. That should be simple.



My home blind test will be just that; three el-cheapo drugstore cables which sound exactly the same and a $170 USB cable. Probibly do the test tomarrow. And probibly do another test down the line as there is no proof unless it can be always repeated with consecutive same results.


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## bigshot (Nov 26, 2018)

When you have completed your test will you lend your cables out for someone to verify your findings? Repeatability has to come from an independent source. Otherwise people could just say that they conducted a test and make up the results they want and not actually do it. We wouldn't want to let that be a possibility. We want to know for sure.


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## Redcarmoose (Nov 26, 2018)

bigshot said:


> AI don't care about higher grade audio at this point. That is a subjective evaluation. I want to verify and identify the objective difference first. He says that he had between 70% and 100% accuracy identifying three different sounds. All I need is two that sound clearly different. That should be simple.
> 
> There's no point going to the trouble of describing subjective impressions of differences until you know for sure the differences exist and what causes them. That is the huge problem with the way people approach these things. They start out with a subjective impression, then they come up with a theory that assumes it's true, then they start cherry picking data to fit their theory. That is bass ackwards. You have to start out by dead to rights nailing down that there actually IS a difference before you start thinking up reasons why it exists.



Strangely in visual tests be it placebo or new toy bliss, it’s clearer overall with tighter more defined bass, deeper soundstage, wider soundstage and brighter more detailed treble. Also better pace and imaging. All the stuff you would want, though it may not be true?

But I do get what your saying about anything better being subjective.


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## bigshot (Nov 26, 2018)

A cable either conveys its signal perfectly, or it corrupts the signal along the way. There is no such thing as "better than perfect". If two cables sound totally different, one or both of them are corrupting the signal. The goal then is to figure out which one (or both of them) is doing that.

I don't need descriptions. I just want two cables that sound clearly different. That is the starting point. If you can provide that, we can get started.


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## Redcarmoose

bigshot said:


> When you have completed your test will you lend your cables out for someone to verify your findings? Repeatability has to come from an independent source. Otherwise people could just say that they conducted a test and make up the results they want and not actually do it. We wouldn't want to let that be a possibility. We want to know for sure.



I get what your saying about an independent test being truthful, but I’m simply stating that what ever the outcome is for myself, folks should at least try. Especially if they are into finding every last % of sonic quality.

Here we read of one person who feels they have received an improvement, though we don’t know the final purchase.

I simply feel I know very little and don’t read anything convincing enough, and I want to know if there is a truth unknown.


----------



## GrussGott (Nov 26, 2018)

Redcarmoose said:


> The question is what did he keep!


I kept the AQ Carbon.  I've also tried other cables, not always on my system like curious, sablon, and others and for me right now they're not worth the money.

As for the technicalities, i've already detailed exactly how and why digital cables can change the sound: it's because we want:
10011010-tick,tick-00110101-tick,tick-11010001-tick,tick etc

and due to noise and jitter we _*might *_get
10011011-tick,tick-00110101-tick-11000001-tick,tick,tick etc

Thus if the output amplitude and/or timing decodes different than what was sent, that get passed on to your amplifier and you _*may *_hear it. That's the generalities.

From there we can talk about buffers, frames, asynchronous, isochronous ...  but ultimately we're slaves to:
(1.) the USB Audio Spec, which dictates guaranteed bandwidth but no error correction (i.e., it's a live feed as opposed to a file transfer which is USB bulk mode with error correction), and
(2.) XMOS and C-Media chips, which in the words of Jason Stoddard, "nobody knows what they hell they're doing"

So really it comes down to this ... either:

*(1.)* big-shot and the rest of the cables-don't-matter crew are just smarter than all of the audiophiles, scientists, and engineers who disagree which also means all of the vendors selling cables (and other decrapifier products?) are hucksters knowingly defrauding their customers, or

*(2.) *big-shot and the cable denier crew are shills for the low-cost cable industry, and trying to deceive us all into buying low-cost cables, or

*(3.)* Noise and jitter on digital cables can affect sound quality (not "roll" sound) however whether any individual can hear that in their system could be a high bar to cross depending on your ears, equipment, and environment

Personally, I'm sticking with #3 and my AQ Carbon until I hear what Schiit comes out with as a newly certified USB Special Interest Group.  I'm guessing that'll lessen or eliminate the need for fancy cables, decrapifiers, and other such items.

Lastly I'll say again, *my advice, FWIW, would be to invest in cables last, especially digital ones*.  Pay attention to people Atomic Bob who test USB cables in professional environments, he uses schiit PRYST or AQ forest type cables, so good but not ultra fancy.

BTW, AQ carbon does well in professional testing:


----------



## bigshot

Redcarmoose said:


> I get what your saying about an independent test being truthful, but I’m simply stating that what ever the outcome is for myself, folks should at least try. Especially if they are into finding every last % of sonic quality.



That's fine. Everyone should be doing controlled tests to learn for themselves how things work. If you run across something strange that doesn't make sense technically, it's a good idea to run it past someone who knows even better to make sure your test is being controlled properly, and to reproduce your unusual results.

I'm eager to see the results of the verification of the two USB cables that sound clearly different. That would be interesting to chase down the cause of if it's true.


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## bigshot (Nov 26, 2018)

GrussGott said:


> I kept the AQ Carbon.



Is that the one that sounded clearly different than the regular USB cables? If so, we can use that to run a verification test against a regular stock USB cable. Do you think that would reveal a clear audible difference? I'm really excited that we finally have something to test that is clearly different. Thanks for your help!

As I explained before, we don't need reasons why this might be happening until after we've verified your listening test and done measurements. Hold on to all that info until after that. We can test for those specific things once we document that difference clearly. I'm not going to read that stuff right now. I'll bookmark it for when the time comes.

Is there anyone out there in Sound Science land who is set up to do a controlled listening test and data rate test on a USB cable who will volunteer to help verify this? Let us know. If no one else is available, I can do it, but I think there are people here who can do a better job with the technical measurement stuff than me.


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## castleofargh (Nov 27, 2018)

GrussGott said:


> I kept the AQ Carbon.  I've also tried other cables, not always on my system like curious, sablon, and others and for me right now they're not worth the money.
> 
> As for the technicalities, i've already detailed exactly how and why digital cables can change the sound: it's because we want:
> 10011010-tick,tick-00110101-tick,tick-11010001-tick,tick etc
> ...


 a few posts back you posted some graph showing how the code would be misread. the graph suggests too much delay, or possibly speeds the cable or whatever else can't handle. but how is that relevant to USB cables? are you using some defective old USB1 cable to stream 32/384 music on a non async DAC?

below that you posted the voltage equivalent to bit values at the output of the DAC(it the FS output is 2V). so that has nothing to do with USB and I'm gonna say, cool.

and now you post a graph showing what goes on when we squeeze the USB cable. I can see some more or less nomadic uses of USB(but then wouldn't people use really short cables instead of those?), I also expect that a significant group of audiophiles isn't playing with the USB cable between their computer and DAC all day long. so they won't be too concerned by this graph.


 basically, you make up reasons to be scared about noise and errors while suggesting that an audiophile USB cable is somehow going to save the day and sound better/different. and that to you is fine. but when bigshot or others explain why there are really no reason for a proper standard USB cable not to do the job just fine, why if you have issues they're just as likely to have other causes, and why your subjective impressions are no evidence of audible change, then they're shills.
 I'm going to indeed pay attention to what @atomicbob did, and conclude that a 20$ usb cable can do a very fine shielding job, so it's probably not necessary to spend much for that reason.

about the all "they do" vs "they don't" BS strawman debate. it's not what most people contest when you or others post about how much better the new cable sounds as "proof" that indeed USB cables make audible changes. I for one tend to disagree with all the generalizations, jumping to conclusion and fishing for causes. I don't care if a usb cable sounds different or not, if it does it does. bring me some sort of evidence, some actual listening test, or some measurements, and I'll accept that probably in your system with those cables, something significant is going on. but when you don't do any of that and instead keep fishing for justifications, opposing or ignoring you is the only proper reactions.
audible difference or not, the way you approach the issue and the way you approach trying to convince people, they're both very much wrong.

to give you a little space to breath, because I'm not a monster. I'll add that I don't like it when someone claims that differences cannot happen. that implies considering all possibilities, all gears, all cables, and that's not something anybody can claim to have done. I say this just to be clear that IMO, wrong methods are wrong, no matter the point they try to support.


----------



## bfreedma

GrussGott said:


> I kept the AQ Carbon.  I've also tried other cables, not always on my system like curious, sablon, and others and for me right now they're not worth the money.
> 
> As for the technicalities, i've already detailed exactly how and why digital cables can change the sound: it's because we want:
> 10011010-tick,tick-00110101-tick,tick-11010001-tick,tick etc
> ...




Can you point me to the names of scientists and/or engineers (who don’t have a vested/financial interest) who believe that the error rate in digital audio data transmission via a non faulty USB cable reaches audible levels when used within spec?

As to Schiit’s “new” USB, the last thing this or any other industry needs is a closed proprietary off standard implementation.  Unless they are committed interoperability testing with every USB product, no good will come of that.  Other than, of course, for the maker of the non standard product.  Now if someone can demonstrate that the current standard if faulty, that becomes a different conversation.  Are we really going back to the equivalent of breakout boxes and serial ports in order to enable dissimilar implementations to communicate?

I understand why it’s beneficial to the manufacturer.  They are developing a built in market for “USB conversion hardware” to enable standard USB port traffic to communicate with a proprietary implementation. Following in the grand audiophile tradition of creating solutions in search of a problem.


----------



## bigshot

I'm happy as long as he helps us do a test to verify that the two cables he lends us sound different. That's all I'm interested in. I've been looking for something like this to test a long time.


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## GrussGott (Nov 26, 2018)

castleofargh said:


> basically, you make up reasons to be scared about noise and errors



Either you're right that digital cables don't matter and everyone who disagrees is just dumber than you (and vendors are knowingly pushing fraudulent products) or the cables can matter.  It ain't a strawman when it's reality.  (unless you want talk QM again, or that we all live in a simulation - then I agree that reality is a strawman)

And, BTW, i'm not encouraging anyone to buy anything (especially cables) before trying it out risk free; ain't no guaranteed anything in the audio game.  ARGH!!

Here's a great video of Guttenberg discussing about how different people react to gear (it's titled selling but he talks all about people impressions of the same gear, same music, same chair, same room: *"you'll learn there's no consensus in audio ... there's no this-is-this ... the interaction between a human and a piece of audio gear is hard to predict" - *is there a biology thread?  that's probably the most important science we should be discussing ...)


----------



## GrussGott (Nov 26, 2018)

bfreedma said:


> Can you point me to the names of scientists and/or engineers (who don’t have a vested/financial interest)



If you believe financial interest has corrupted vendors into knowingly selling fraudulent products, name the vendors and products.

let's start a list of fraudulent USB cable vendors.  Given you're the one convinced of fraud, you go first.

Maybe you're accusing Bill Low, founder of audioquest, of being a huckster?  If the science is settled then you should confront him with it.

Or maybe challenge Paul McGown with your settled science! He doesn't sell USB cables, he's just been designing audio equipment for 40 years, I guess he's just a dummy!  Here, let him tell you himself:



He'd be happy to host you and video you presenting your settled science.


----------



## bfreedma (Nov 26, 2018)

GrussGott said:


> If you believe financial interest has corrupted vendors into knowingly selling fraudulent products, name the vendors and products.
> 
> let's start a list of fraudulent USB cable vendors.  Given you're the one convinced of fraud, you go first.
> 
> Maybe you're accusing Bill Low, founder of audioquest, of being a huckster?  If the science is settled then you should confront him with it.




You made the specific claim that there were engineers and scientists who believed that USB cables made an audible difference due to transmission errors and/or other factors.  When asked to support your claim by supplying names of those with no profit motive, you choose to respond in this manner?  Schoolyard playground tactics aren’t very compelling.

I’ll take this as confirmation that you can’t actually support your claim.

I’d be happy to engage Bill Low, Noel Lee, etc, and ask them to provide  evidence supporting their claims.  Because they certainly don’t make that evidence available on their web sites or in their marketing materials.  Feel free to ask them to post here.

Edit.  A video of a DAC manufacturer verbally stating that he hears differences in USB cables “as soon as he walks into the room” isn’t compelling, it’s comical.  It’s certainly not supporting evidence, let alone validation.


----------



## GrussGott (Nov 26, 2018)

bfreedma said:


> I’ll take this as confirmation that you can’t actually support your claim.



How about you support your claim of settled science that USB cables don't matter and present it to these vendors - reveal their fraud!   If you're convinced they're wrong then you must have settled science - this is a USB cable after all!  (in spec is all you need, it's just science and you're an expert!)

If you won't do that, I'll take it as confirmation you have no settled science.

it's too bad you can't support your claims.


----------



## bfreedma (Nov 26, 2018)

GrussGott said:


> How about you support your claim of settled science that USB cables don't matter and present it to these vendors - reveal their fraud!   If you're convinced they're wrong then you must have settled science - this is a USB cable after all!  (in spec is all you need, it's just science and you're an expert!)
> 
> If you won't do that, I'll take it as confirmation you have no settled science.
> 
> it's too bad you can't support your claims.



I made no claim - I simply asked you to support yours via independent sources.  Nothing unusual or controversial there.

When you have something substantive to discuss in support of the claims you made I’ll be happy to reengage.  I’m not wasting more time with your grade school level debate tactics.


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## GrussGott (Nov 26, 2018)

bfreedma said:


> I made no claim - *I simply asked you to support yours with via independent sources*.  Nothing unusual or controversial there.



Oh, well the only claim I made was that I heard a difference with USB cables and then provided why I think that it is, but I ain't no digital signals processing expert.

But* let's go back to the core question* and *I'll explain why you are, in fact, making a claim:*

What are possible scientific answers to the following question: can USB cables, between the source and DAC, impact sound quality in an audible way?

*(1.) No, the science is definitive, *USB cables cannot impact sound quality.
*
(2.) Unknown, the science isn't conclusive *one way or another.
*
(3.) Yes, the science is definitive, USB cables can impact sound quality *in an audible way

I think we call agree that #2 is eliminated since, if it were true, we'd likely not have a USB interface, so that leaves #1 and #3.  Thousands of people (like me) have informally tried USB cables out and found them to have an impact, thus if we had to pick, we'd say #3.  And given many vendors make these cables and products, they'd select that answer as well.

Now here you are, claiming we're all either liars, cheats, fools, and/or victims of placebo effect.  In short, *you're claiming our experience cannot be due to the underlying physics *of the medium - thus you must be claiming #1: there is definitive science that proves our experience is false.

*If #1 is indeed true, it should be quite easy for anyone to prove it *- _since it's just how the USB transmission works! 
_
(and if you don't know the conclusive science by now, you never will, so your only _reasonable_ conclusion can be it's possible - said differently, you should be asking the deniers for proof it's impossible since, if true, that should be easy for them to prove)
----------------------

Maybe this will help:

My visual experience is that the Earth is flat ... *Is the Earth flat?*

*(1.) No, the science is definitive, the Earth cannot be flat*
(2.) Unknown, the science isn't conclusive
(3.) Yes, the science is definitive, the Earth is flat

Can we prove a negative when the science is conclusive?  Easy!  I bet it wouldn't take you more than 5 minutes with Google to prove the Earth is round.

And see why asking someone to "prove their claim" the Earth is flat would be useless to you?  Why waste your time when you know and can prove the Earth is round?

If USB cables can't impact heard audio quality - if that's scientific fact - it should be trivial for any of you to prove (and it should be super easy to Google why)


----------



## castleofargh

GrussGott said:


> Either you're right that digital cables don't matter and everyone who disagrees is just dumber than you (and vendors are knowingly pushing fraudulent products) or the cables can matter.  It ain't a strawman when it's reality.  (unless you want talk QM again, or that we all live in a simulation - then I agree that reality is a strawman)
> 
> And, BTW, i'm not encouraging anyone to buy anything (especially cables) before trying it out risk free; ain't no guaranteed anything in the audio game.  ARGH!!
> 
> Here's a great video of Guttenberg discussing about how different people react to gear (it's titled selling but he talks all about people impressions of the same gear, same music, same chair, same room: *"you'll learn there's no consensus in audio ... there's no this-is-this ... the interaction between a human and a piece of audio gear is hard to predict" - *is there a biology thread?  that's probably the most important science we should be discussing ...)



well at least you confirm my point through your actions. it's something I guess. IDK what to say, maybe read my post again? maybe don't.
and yes your first sentence is a strawman argument. what else could that possibly be?


----------



## GrussGott

castleofargh said:


> well at least you confirm my point through your actions. it's something I guess. IDK what to say, maybe read my post again? maybe don't.
> and yes your first sentence is a strawman argument. what else could that possibly be?



Well, I'll give you this Argh, it's reality with some strawman inclinations as written. 

I get being frustrated with overblown claims of cable rolling, USB cables sounding "warmer", etc and I'm sure there are few huckster vendors, ( but I don't know any, so if you do I'd love to see the list. )

What I don't get is kicking back and attacking other's experience rather than ignoring that and putting effort into the science and just proving the discrete set of what is true (and therefore what can't be).

Proving it's impossible for USB cables to impact sound quality should be trivial ... if true.


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## bigshot (Nov 27, 2018)

GrussGott said:


> Proving it's impossible for USB cables to impact sound quality should be trivial ... if true.



You haven't replied to my questions lately. You're interested in working with us to find out the truth about this stuff, right? Can you please let me know which cable you still have that sounds clearly different than a standard printer cable? Let's not get distracted. Let's keep our eyes on the prize... documenting the difference in your cable and measuring it. I've never found a cable that can be proven to sound different. I'm very interested in doing that if you will help.


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## WoodyLuvr (Nov 27, 2018)

GrussGott said:


> So really it comes down to this... either:
> 
> *(1.)* big-shot and the rest of the cables-don't-matter crew are just smarter than all of the audiophiles, scientists, and engineers who disagree which also means all of the vendors selling cables (and other decrapifier products?) are hucksters knowingly defrauding their customers, or
> 
> ...


Good sir, I have absolutely no dog in this fight (aka debate). I do though believe that emotion should be taken out of the equation as it does tend to prevent one to see and understand a different perspective. Unfortunately audio science is rather emotional and highly subjective at that, whether intentional or not, and clearly never black and white as would be more conducive to objective matters at hand... again unfortunately it has some awfully gray areas in which USB cables and cabling in general would fall well into.

*"just smarter than all of the audiophiles, scientists, and engineers who disagree"
*
A few of the gents you are debating and referring to actually fall into that category... I do hope you realize that and have taken that into thoughtful consideration. Since when do all agree, all the time? It sure doesn't happen in the real world...if they did all fully disagree or agree we simply would have a single product to show for it. How fortunate it is not that way!

*"which also means all of the vendors selling cables (and other decrapifier products?) are hucksters knowingly defrauding their customers"*

Vendors typically are very weak on the science and that is perfectly fine but what irks scientists and engineers alike is that they sometimes tend to bring science into the picture and rather incorrectly. I think we all could easily say that the business world tends to stray from science and fairness when it comes to the mighty dollar... sometimes very far but that is not to say there are not some excellent, above board technology manufacturing companies operating out there, it is just very hard to keep it real when it comes to marketing, sales, and achieving those profit margins. 'Fudgery', no matter how innocent, is ultimately unavoidable in the extremely fickle consumer-world of business.

With that said may I offer, with all due respect, a possible *fourth option*... a much simpler one by Occam's razor principal that...

*4.)* One might be simply misinformed and/or not quite comprehending and/or fully seeing the science and principals behind the subject they are debating. That they might be grossly misinterpreting verbiage and/or disagreement in scientific/engineering discourse among professionals and then incorrectly applying blanket assumptions based on such, when in fact the experts were far more closely in-line with each other than one may believe they were and were actually only debating minutiae rather than much broader principals... lucky physics is nice to us in that way. Also, that one may even be unknowingly blinded or biased by their own passion for the subject being discussed. Happens to the best of us, all the time


----------



## bigshot (Nov 27, 2018)

The best way for all of us to agree is for all of us to participate in testing to determine the truth. I'm looking forward to that. I think all of us respect a "put up or shut up" moment. I'm certainly up for finding a cable that sounds clearly different. I just haven't bought one yet.


----------



## GrussGott (Nov 28, 2018)

bigshot said:


> I think all of us respect a "put up or shut up" moment.



I'm with you on that point, here's why:

I think we can all agree that USB, at its simplest, is an electrical transmission encoded at the source by software/firmware, and firmware-decoded at the destination (for our DACs).   That being the case - that we have knowable code written by humans with an intention, we should just be able to ask them:  "Hey inventors of the USB audio transmission code, is it possible or impossible for audio quality to be affected by the medium between two devices?"

Answer: "Well, at the source we start with [ _set of all possible inputs_ ] then we encode that with [ _set of possible algorithms_ ], transmit it, and it's decoded at the destination by [ _set of possible algorithms_ ] resulting in [ _set of possible outputs_ ] therefore, [ _answer_ ].

That's all we need.

Thus the assertion that "all we need is an in-spec cable" is a claim with only assumptions to back it up.  (since nobody has ever produced a code analysis, right?  ... I'm not making any claims, only sharing my experience and why I believe it's happening, but i'm not a digital signals processing scientist)

So the real proof, the real "put up", is to simply produce that code and the analysis, and then we're good.


----------



## GrussGott

WoodyLuvr said:


> A few of the gents you are debating and referring to actually fall into that category... I do hope you realize that and have taken that into thoughtful consideration.



Well, I'll say this, with wisdom comes humility; and this entire thread is really lacking in humility.


----------



## Steve999 (Nov 28, 2018)

GrussGott said:


> Well, I'll say this, with wisdom comes humility; and this entire thread is really lacking in humility.



LOL (for real). Well, I don't agree with you on much, but you've got a damn good point there.


----------



## bigshot

GrussGott said:


> the assertion that "all we need is an in-spec cable" is a claim with only assumptions to back it up.



I'm offering to help you prove it wrong. There are other people here in this forum who will help. Are you going to jump in and participate, or are you going to ask us to take you purely at your word that you conducted a blind test and found a cable that isn't audibly transparent to every other cable? Because people who come in here and claim that they "know for sure" but aren't willing to help back it up are dime a dozen.

Please answer yes or no... no need for explanations. Are you going to help us verify your observations or not?


----------



## castleofargh

when anybody designs a product, he's under the assumption that the cables will be standard in his circuit and tests. or he'll provide the special cable himself if something special is required/helpful in his design. just like a DAC manufacturers will expect about 5V DC from the usb, and that the amplifier's input will be at least a few thousand ohm, those designers have expectations about the USB cable. we owe the wild compatibility between gears to accepted standards, and to good guys manufacturers trying to stick to them. 
so while even outside the notion of audibility, there is at least always a potential for improvement and it's fine to seek such improvements, it seems legitimate to wonder how often we end up degrading a system when introducing an atypical element in the chain? 
as always my own train of thoughts leads me to the need for measurements of the signal coming out of my gears, instead of believing in magic audiophile USB cable technologies, and/or subjective impressions pretending to judge fidelity.


----------



## GrussGott (Nov 29, 2018)

bigshot said:


> Please answer yes or no... no need for explanations. Are you going to help us verify your observations or not?



No.  But only because your methodology is flawed, here's why:

Any amount of empirical testing on various home setups (or show setups) can - AT BEST - show (not prove):

On that day ...
At the time of testing ...
With that equipment ...
In that environment ...
With those people ...
There was an experience of something.  That's pretty non-conclusive except at high levels of iteration, sample size, rigor.

*INSTEAD, I'd offer two alternative approaches:*

Someone visit Paul McGown at PS Audio in Denver and conduct the testing in his music room 1 (with the IRS setup)
We run the code analysis
Why?  Well the first offers controls of

The listener(s).  Paul is an experienced listener who claims he can tell the difference between USB cables AND
The equipment.  Paul has some of the best sources and DACs in the World, a bunch at his fingertips AND
The environment.  Paul's listening room 1 IRS setup is a fixed place he's claimed to have heard differences AND
Level of Effort.  I'm sure Paul would be happy to run the tests and video the whole thing.  AND
Probability.  If a difference can't be heard with this level of equipment and tuning, then effectively there is likely no difference
Here's measurements nerd Jon Atkinson (stereophile, so familiar room) preparing for a listen in that very room:






If you're curious about the 2nd reason (and you're not), it's because, while I've explained why I believe I'm hearing a difference (noise & jitter), it might be something else such as some quality of cable as it interacts with the chip sets on the receiver end.  For example the firmware code might trigger various algorithm based on the resistance/impedance/capacitance of the cable or varying amounts of those qualities.  For example, person 1 uses the same cables connected to an XMOS chip, cable is stationary, no changes.  Person 2 uses the same cables, C-Media chip, cable is slightly vibrating due to outdoor traffic triggering some different algorithm which changes the outputs.

There are a billion reasons within the software/firmware code and it's input/output values of how, when, where changes could be impacted.  For that reason, in the above test I'd recommend that varying lengths of cables be used and a disturbance test applied.


----------



## Triode User

The big point that all you guys are missing is the current understanding that RF and other noise carried on USB can disrupt the DAC. And before you say it, it is not enough to merely repeat that mantra that any competent DAC should be perfectly capable of filtering out that noise. In reality they cannot do that to the point where they can cope with typical levels of RF noise. 

So why mention this is a thread about usb cables? Well some usb cables can act as aerials to this noise. Some can attenuate it. Some can even generate it themselves. 

I admit my hobby turned into a business is making cables that filter RF noise but I do not do usb cables so I have no interest in promoting a product there. But what I do contend is that RF noise is the elephant in the room to do with digital music and I put forward the suggestion that this may be why some people assert that usb cables sound different to each other.


----------



## GrussGott (Nov 29, 2018)

Triode User said:


> The big point that all you guys are missing is the current understanding that RF and other noise carried on USB can disrupt the DAC. And before you say it, it is not enough to merely repeat that mantra that any competent DAC should be perfectly capable of filtering out that noise. In reality they cannot do that to the point where they can cope with typical levels of RF noise.



Yeah, exactly which is why this whole thread is out of hand with assumptions and conjecture and "you're making claims".  Everyone here is making claims, either based on their experience and/or their assumptions and conjecture (and whining about their CVs).  ("i experienced yes, here's why i'm guessing that is" "I experienced no, here's why I'm guessing that is" - those are both claims)

Thus the simplest way to approximate an answer is to test on the most expensive (detailed) setup we can - one that many audiophiles have heard and understand - with people who are experienced listeners.

All we'd need to show in that setup is a few people can predict the cable change via unlimited A/B testing ("play a again ... ok now b ... b again ... ok now a ... etc).  If those experienced listeners can't (and they previously claimed they could) then we could say it's likely not probable.


----------



## bigshot (Nov 29, 2018)

GrussGott said:


> No.



OK.. I get it. You're a duffer. You're lying about doing a controlled test too. You just made up your mind and you'll say anything and cherry pick and obfuscate to try to push that across. There's no reason to believe that a USB cable can sound different. There's no reason to believe you. What a waste of time people like you are. Don't say I didn't give you a chance.

NEXT!


----------



## bigshot

Triode User said:


> The big point that all you guys are missing is the current understanding that RF and other noise carried on USB can disrupt the DAC.



Good point! And how would that manifest itself? Not in "veils" or "soundstage" or "detail", but in dropouts. Very audible dropouts. When we're talking about that sort of thing, we are talking about a defect in the design of the cable. USB standard has specifications to minimize that possibility and cables are tested to gain certification. RF interference like that would be blatantly obvious and it would result in easily measurable data corruption. Since audio files are relatively small and the data rate to play audio buffered through a DAC is not very demanding, something like that would have to be pretty bad before sound quality would start glitching. A cable like that would be unable to pass large files from hard drive to hard drive at top speed. Yet the cheap USB cable that comes with your pocket hard drive works fine. Have you ever run across any properly functioning USB cable that didn't? I haven't. I don't think it's a very likely scenario.

But that wasn't what this guy was talking about. He was claiming that expensive USB cables *sound better* than properly functioning inexpensive ones. That isn't the same as saying that improperly shielded USB cables can introduce errors.

I think that guy hasn't ever done a controlled test in his life. He was lying through his teeth for the past week. In fact, I am quite confident that if I went through his posting history here at Head-Fi, I would find post after post where he argues that blind testing isn't accurate. I'm not interested in what he has to say though, so I'm not going to waste my time. I've got bigger fish to fry than to worry about self validating people who talk too loud in public places.


----------



## Triode User

bigshot said:


> Good point! And how would that manifest itself? Not in "veils" or "soundstage" or "detail", but in dropouts. Very audible dropouts. When we're talking about that sort of thing, we are talking about a defect in the design of the cable. USB standard has specifications to minimize that possibility and cables are tested to gain certification. RF interference like that would be blatantly obvious and it would result in easily measurable data corruption. Since audio files are relatively small and the data rate to play audio buffered through a DAC is not very demanding, something like that would have to be pretty bad before sound quality would start glitching. A cable like that would be unable to pass large files from hard drive to hard drive at top speed. Yet the cheap USB cable that comes with your pocket hard drive works fine. Have you ever run across any properly functioning USB cable that didn't? I haven't. I don't think it's a very likely scenario.
> 
> But that wasn't what this guy was talking about. He was claiming that expensive USB cables *sound better* than properly functioning inexpensive ones. That isn't the same as saying that improperly shielded USB cables can introduce errors.
> 
> I think that guy hasn't ever done a controlled test in his life. He was lying through his teeth for the past week. In fact, I am quite confident that if I went through his posting history here at Head-Fi, I would find post after post where he argues that blind testing isn't accurate. I'm not interested in what he has to say though, so I'm not going to waste my time. I've got bigger fish to fry than to worry about self validating people who talk too loud in public places.



You ask how how the RF noise manifests itself. Usually by a harshness or hardness to the top end. Often it is mistaken for extra detail or extra ‘soundstage’. Better to describe how it sounds when it is gone which is smoother or ‘darker’. This is normally not a subtle change and is easily audible. 

But it is not a change to any ones or noughts and it does not cause glitching or outs. 

Nor is what I am describing due to improperly shielded cables. Often the noise is generated by a component in the system and it is transmitted as common mode noise in the cable. 

Some people use an alternative optical connection as a reference method because this breaks the RF noise chain.


----------



## GrussGott (Nov 29, 2018)

bigshot said:


> OK.. I get it. You're a duffer. Don't say I didn't give you a chance.









Dude.  you're a laughable twit.  How much of your self-identity do have in this forum??  Answer: 100%


----------



## bigshot (Nov 29, 2018)

Triode User said:


> You ask how how the RF noise manifests itself. Usually by a harshness or hardness to the top end. Often it is mistaken for extra detail or extra ‘soundstage’. Better to describe how it sounds when it is gone which is smoother or ‘darker’. This is normally not a subtle change and is easily audible. But it is not a change to any ones or noughts and it does not cause glitching or outs. Nor is what I am describing due to improperly shielded cables. Often the noise is generated by a component in the system and it is transmitted as common mode noise in the cable. Some people use an alternative optical connection as a reference method because this breaks the RF noise chain.



If I'm reading you right, it isn't a problem with the cable really. It is lack of isolation from RF in the component. I'm assuming we're talking just about DACs and computers since you don't connect an amp with USB. How common is this? I've never run across it at all, but I mostly own Macs and iPods/iPhones and standalone disc players. I only have one DAC, the Oppo HA-1 and I'm sure it doesn't have that problem.

Would the solution be to replace the DAC? It doesn't seem that a fancier USB cable would be the solution since you say it isn't a shielding problem. A USB cable could be wrapped in pure unobtanium and still have the problem. You say that people describe the interference as "more detail" and "better soundstage". Those are terms that we hear describing the sound of high end cables. Why would high end cables be more susceptible to this interference than a regular Amazon basics cable?

I remember Gregorio mentioning something like this a long time ago, but it flew over my head because I don't know how the IO ports on a DAC work. Am I understanding you correctly here?


----------



## Glmoneydawg

GrussGott said:


> No.  But only because your methodology is flawed, here's why:
> 
> Any amount of empirical testing on various home setups (or show setups) can - AT BEST - show (not prove):
> 
> ...


Arnie Nuddel made some great speaker systems....i would like a set of those even if they didn't produce music.


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## WoodyLuvr (Nov 29, 2018)

GrussGott said:


> Well, I'll say this, with wisdom comes humility; and this entire thread is really lacking in humility.


@GrussGott Would it be safe for one to assume that the USB cable you heard a difference with is the very one you have told us that you are keeping? AQ Carbon...


----------



## Triode User

bigshot said:


> If I'm reading you right, it isn't a problem with the cable really. It is lack of isolation from RF in the component. I'm assuming we're talking just about DACs and computers since you don't connect an amp with USB. How common is this? I've never run across it at all, but I mostly own Macs and iPods/iPhones and standalone disc players. I only have one DAC, the Oppo HA-1 and I'm sure it doesn't have that problem.
> 
> Would the solution be to replace the DAC? It doesn't seem that a fancier USB cable would be the solution since you say it isn't a shielding problem. A USB cable could be wrapped in pure unobtanium and still have the problem. You say that people describe the interference as "more detail" and "better soundstage". Those are terms that we hear describing the sound of high end cables. Why would high end cables be more susceptible to this interference than a regular Amazon basics cable?
> 
> I remember Gregorio mentioning something like this a long time ago, but it flew over my head because I don't know how the IO ports on a DAC work. Am I understanding you correctly here?



What I am trying to put forward is the scenario where there is an issue of RF noise in a system which when it gets into the dac analogue stages can modify the sound we hear. Then what I am saying is that based on my experience with other digital cables perhaps what people hear with usb cables is a situation where usb cables either intentionally or unintentionally reduce or increase the RF noise. I freely admit my experiences are with BNC digital cables and that I am extrapolating that to assume the issue is applicable with usb. With the BNC cables I design them to filter the RF noise. My own 'blind' experiments in the sense that all cables are in position and I merely swop over the connections without revealing which cable is which have so far given 100% success rates with people successfully identifying the RF filtering cables.

I have not found that swopping DACs is as effective. Although they all do appear to have different levels of internal filtering or isolation I have yet to find one which successfully filters out all the RF noise coming in on the input cable.

It is interesting though that some of the so called high end digital cables are actually the worst performers because they can increase the RF noise either by resonance or by acting as an RF aerie to pick up even more RF noise. From routers or DECT phones for instance.

So I am suggesting a possible reason for people to hear differences due to usb cables, not all, but some. Again based on my experiences with BNC cables some people do sometimes pick out the worse performers as their favourite. I think this often happens because they hear that as a difference from the other cables and assume it is better. The usual give away is when they state the reasons for preferring the cable as being that it has more detail, more top end shimmer, more life, more soundstage. In my experience these are all descriptions of a difference in sound due to there being more RF noise in the system. And yes, I agree that high end (ie more expensive) digital cables often attract those descriptions and yes I would say that they are the the worse performers if that is how they are described for the effect on the sound.

Throughout all this though, one has to accept that it is not sufficient merely to say that any competently designed and implemented DAC will filter out the common mode RF noise. It seems to be able to jump over or get through internal isolating transformers and internal ferrites or at least in sufficient quantity to still be an issue in the analogue stages of the DAC.

In summary, in an ideal world the digital signal supplied by the digital source will be RF free and in those circumstances all competent digital cables should sound the same. I am saying that most digital sources have differing amounts of overlaid RF noise on their output signal and it is possible for digital cables to modify that RF noise. The RF noise becomes audible by interfering with the music in the analogue stages of the DAC and hence why it is possible to accept that digital cables, including usb cables, can have an effect on the music.


----------



## bigshot

Triode User said:


> What I am trying to put forward is the scenario where there is an issue of RF noise in a system which when it gets into the dac analogue stages can modify the sound we hear. Then what I am saying is that based on my experience with other digital cables perhaps what people hear with usb cables is a situation where usb cables either intentionally or unintentionally reduce or increase the RF noise. I freely admit my experiences are with BNC digital cables and that I am extrapolating that to assume the issue is applicable with usb.



Are BNC cables used to transfer digital data? I've only seen them used for analog video. And I imagine an analog video signal doesn't resemble a digital signal or the hardware involved with input at all. If BNC cables are used for digital signals, then they definitely would be comparable. Perhaps Gregorio knows something about this that would clarify it.


----------



## gregorio (Nov 30, 2018)

GrussGott said:


> Why? Well the first offers controls of
> 
> The listener(s). Paul is an experienced listener who claims he can tell the difference between USB cables AND
> The equipment. Paul has some of the best sources and DACs in the World, a bunch at his fingertips AND
> ...




Every single one of those points is nonsense!
1. There are numerous engineers who are not only much more "experienced listeners" but formally trained. AND
2. World class studios have at least as good or better equipment, plus the original mixes/masters AND
3. Paul's listening room is not even in the same ball park as the top recording studios, who've spent millions and sometimes tens of millions on acoustics and equipment!
4. Level of effort isn't even close either.
5. And what if no difference can be heard with a level of equipment and tuning that's far higher than Paul's and by countless engineers who rely on their listening and analysis skills for a living?

If you're going to make a fallacious appeal to authority, at least pick an actual authority!!



Triode User said:


> [1] But what I do contend is that RF noise is the elephant in the room. But it is not a change to any ones or noughts and it does not cause glitching or outs. Often the noise is generated by a component in the system and it is transmitted as common mode noise in the cable.



What room and what elephant? If it's not "ones or noughts" what else is there in digital audio? What else could there be and why is it not incompetent if it's not already eliminated completely by the digital audio process itself or reduced to well below audibility if it isn't?

G


----------



## gregorio (Nov 30, 2018)

bigshot said:


> If BNC cables are used for digital signals, then they definitely would be comparable. Perhaps Gregorio knows something about this that would clarify it.



Yes, they are used in a couple of places. They're used for wordclock connections and sometimes for S/PDif. RF typically has no effect on digital data recovery through BNC cables even in high interference areas like machine rooms but cables have to be short to avoid the possibility of interference as it's effectively an unbalanced signal, which is why AES/EBU is preferred professionally as it is balanced. BTW, USB is also balanced!

G


----------



## Triode User

bigshot said:


> Are BNC cables used to transfer digital data? I've only seen them used for analog video. And I imagine an analog video signal doesn't resemble a digital signal or the hardware involved with input at all. If BNC cables are used for digital signals, then they definitely would be comparable. Perhaps Gregorio knows something about this that would clarify it.



Yes, the BNC cables are used for digital signals (audio).



gregorio said:


> Yes, they are used in a couple of places. They're used for wordclock connections and sometimes for S/PDif. RF typically has no effect on digital data recovery through BNC cables even in high interference areas like machine rooms but cables have to be short to avoid the possibility of interference as it's effectively an unbalanced signal, which is why AES/EBU is preferred professionally as it is balanced. BTW, USB is also balanced!



The use of digital BNC cables is fairly common with some gear.

USB being balanced will not help prevent it picking up the noise I am discussing because much of it is created by the audio device creating the digital signal. It then gets straight into the USB cable at that point.


----------



## Arpiben

IMHO, I would say that for example ferrites on top of BNC are acting more as a workaround when dealing with item noises from FPGAs or CPUs not properly managed in the device environment.
I should even add that the workaround may be provisory since magnetic properties of ferrites are changing in relation with the energy they are absorbing.
Such noises and workaround benefits can be easily measured and quantified in another way than in audio terms.
I have failed to see such easy measurements published until now in audio.

In my domain, micro and millimeter waves
(up to 160 GHz) transmission lot of care is taken especially when high power transmission circuits share the same box together with very low noise receivers.

I am not pretending that it is an easy task. But when dealing with very CPU demanding processes there are drawbacks apparently not always taken into account by audio manufacturers.

As such, @Triode User cables may be a provisory solution when connecting some upscaling equipment to a DAC.

What annoys me is the lack of quantification in scientific terms.Without it difficult, at least for me, to tell or prove if it really matters or exists.

A simple null test at the end of the chain should also bring interesting results....


----------



## bigshot

You guys have left me in the dust.

I'm curious if anyone thinks that this is a common problem with average consumers connecting a source and DAC in a home audio system?
And if it is, is there any reason to believe that a more expensive USB cable would solve the problem better than a regular old Amazon basics one?
If not, how would someone go about correcting the problem?


----------



## Triode User

bigshot said:


> You guys have left me in the dust.
> 
> 1. I'm curious if anyone thinks that this is a common problem with average consumers connecting a source and DAC in a home audio system?
> 2.  And if it is, is there any reason to believe that a more expensive USB cable would solve the problem better than a regular old Amazon basics one?
> 3. If not, how would someone go about correcting the problem?



1. I guess it depends on what you call an average sytstem. It is possibly not an issue with many systems because they might mask the problem sound and as I mentioned, my direct experience is with BNC digital audio cables and not USB. However many of my customers for my RF noise filtering cables have what I would call good digital systems rather than exotic and they can hear the clear difference when RF noise is removed. An email from one today for instance has a Xindak CD Transport and a T&A DAC8. He could hear a problem, now it is solved, ie harshness removed.

2. Expensive does not equal better. The USB cable only needs to comply with the USB transfer standards in order to work properly in terms of digital transfer. I use ferrites on my BNC cables to filter the common mode noise. The question would be whether anything can be done to a USB cable to filter the noise. The ferrites work very effectively on the common mode noise in BNC cables and they might work on USB as well. 

3. Design digital sources need to be quieter with respect to the noise they have in their digital circuits. Innuos is one company which is doing this.  At the cheaper end of the market companies are now producing boards to link to the Raspberry Pi which are keeping the clean supplies separate from the dirty circuits.


----------



## castleofargh

Arpiben said:


> IMHO, I would say that for example ferrites on top of BNC are acting more as a workaround when dealing with item noises from FPGAs or CPUs not properly managed in the device environment.
> I should even add that the workaround may be provisory since magnetic properties of ferrites are changing in relation with the energy they are absorbing.
> Such noises and workaround benefits can be easily measured and quantified in another way than in audio terms.
> I have failed to see such easy measurements published until now in audio.
> ...


yup, without even a vague sense of the magnitudes involved, I only see paranoia and scare tactics.


----------



## bigshot (Nov 30, 2018)

Triode, do you happen to know the degree of attenuation of the noise we're talking about? Would it be above -50dB?

It appears that cables really aren't the issue here. That was what I originally thought. It isn't the job of the cable to filter out noise caused by the source. All a cable has to do is carry the signal without degrading it. I imagine Amazon Basic USB cables do that just fine. If the source has a design flaw, it should be corrected there, not by trying to slap a band aid on it by filtering.


----------



## Triode User

castleofargh said:


> yup, without even a vague sense of the magnitudes involved, I only see paranoia and scare tactics.



Or, and just play along with me, you could listen to the change, see if you hear a difference and if you did then you could try to work out what is going on. 

No one is trying to scare you. 

And magnitudes are fine but there is life outside of numbers. For instance I asked a mechanic what torque setting he used on a 7.5 ton truck wheels. Without blinking he said, “FT”. Work it out, it doesn’t involve numbers but it works. 



Boo!


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## bigshot (Nov 30, 2018)

I can parse a number. It may not tell me the whole story, but it can give me a general idea. An anecdotal customer testimonial doesn't tell me much at all. I've seen those used to sell things that are complete hooey. I really don't see how this is a serious problem if no one bothers to measure it. It's interesting to hear about DACs that have design flaws that reveal noise. Can you tell me a specific make and model that has been reported as having that problem? Has that been measured and quantified in any way?


----------



## GrussGott

WoodyLuvr said:


> @GrussGott Would it be safe for one to assume that the USB cable you heard a difference with is the very one you have told us *that you are keeping? AQ Carbon.*..



Yes, but it's "kept" as I did that stuff awhile ago.  Occasionally I still play around with optical cables, interconnects, and headphone cables, but none of that improves anything I can hear with my equipment.

Overall I think USB cables are a pretty minor component except in unique cases thus the only reason I post here is because all the bogus information and jackassery that's tolerated in this thread annoys me.


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## bigshot (Nov 30, 2018)

He claimed to be able to identify three different groups of USB cables blind with 100% certainty with a gap between samples of at about 10 seconds. Now he says that the difference is pretty minor. He never did any test. He just makes stuff up to suit his argument.


----------



## Redcarmoose (Dec 1, 2018)

bigshot said:


> He claimed to be able to identify three different groups of USB cables blind with 100% certainty with a gap between samples of at about 10 seconds. Now he says that the difference is pretty minor. He never did any test. He just makes stuff up to suit his argument.



Go back it’s 70% accuracy. The difference that your going to get is always minor, but when you add small improvements on top of small improvements you start to get a larger improvement. He posted here because I showed interest in starting a test. By chance we both own AudioQuest Carbon USB cables. He chose his cable after testing both cables which were lower cost and cables which were higher cost. I purchased my cable after a sincere recommendation from someone knowledgeable and experienced at Head-Fi.

I’m still getting ready to do my testing, but you can rest assured I’m going to do all I can to make it as honest and correct as possible.

If you think we don’t have better things to do than contrive deceitful stories to post on-line; I truly don’t know what to say. My outcome has not been discovered as of yet. I’m now believing USB cables couldn’t make a difference. I never noticed any change with my $5 USB cables regardless of it being 3’ or 10’. I also never noticed an improvement sighted with other cheap brands, but in sighted tests the Carbon is noticeable as an improvement. I’m burning it in for 200 hours and getting to know the sound signature to help identify it during the testing routine.

We are posting here to help people in order that they could give a cable a try or not. If I can’t distinguish a difference in non-sighted testing I will recommend there is no difference between cables and recommend not to waist $170 on a silly cable.

But I respect the test results just posted. The person is trying to ascertain a reality which could help new readers obtain better sound.


----------



## bfreedma

Redcarmoose said:


> Go back it’s 70% accuracy. The difference that your going to get are always minor, but when you add small improvements on top of small improvements you start to get a larger improvement. He posted here because I showed interest in starting a test. By chance we both own AudioQuest Carbon USB cables. He chose his cable after testing both cables which were lower cost and cables which were higher cost. I purchased my cable after a sincere recommendation from someone knowledgeable and experienced at Head-Fi.
> 
> I’m still getting ready to do my testing, but you can rest assured I’m going to do all I can to make it as honest and correct as possible.
> 
> ...




Just because you’re sincere doesn’t mean other parties are.


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## Redcarmoose (Nov 30, 2018)

bfreedma said:


> Just because you’re sincere doesn’t mean other parties are.



I think it’s fine to view the positive results with contempt. I view most of the magazines and “people-in-the-industry” posts as having an ulterior motive. Our beloved hobby is trudging along, actually wallowing in really well in contrived BS to further fill the bank accounts of the best with the best slant.

Most of the time I don’t respond to try and attack the sales attempts here.

The problem is many are truly looking for truth and we are plagued by insincere untruths which make the journey more difficult. It’s the dualities of our world maybe?


----------



## Brooko

Redcarmoose said:


> I’m burning it in for 200 hours and getting to know the sound signature to help identify it during the testing routine.



You lost me here.  What difference could "burn-in" possibly have on a wire - no capacitors, no electronics, just wire and solder .........

And why 200 hours?  Where is the science behind the time?

Thirdly - how could a cable possibly have a sound signature?  It's wire.  Even different capacitance won't make difference because its between components, so things like impedance can't come into play.  Again - if all its conveying is a digital signal, how can it affect analog output (ie frequency response)?


----------



## bfreedma (Nov 30, 2018)

Redcarmoose said:


> I think it’s fine to view the positive results with contempt. I view most of the magazines and “people-in-the-industry” posts as having an ulterior motive. Our beloved hobby is trudging along, actually wallowing in really well in contrived BS to further fill the bank accounts of the best with the best slant.
> 
> Most of the time I don’t respond to try and attack the sales attempts here.
> 
> The problem is many are truly looking for truth and we are plagued by insincere untruths which make the journey more different. It’s the dualities of our world maybe?




Some of the challenge is certainly people making absolute statements when there may be unique edge cases not likely to be seen in normal use that may be exceptions.  A bigger problem is some posters playing devils advocate as a way to seek attention/obfuscate the issue and the reality that the aforementioned edge cases are outliers extraordinary unlikely to impact anyone.


----------



## GrussGott (Nov 30, 2018)

Redcarmoose said:


> If you think we don’t have better things to do than contrive deceitful stories to post on-line; *I truly don’t know what to say*.


I know what to say!

Bigshot's prancing around like a silly boob are what make this thread the most toxic place in audiophilia!  He and Gregorio really deserve credit for making this the twitter of headphone audio and driving people the feck away from here.  Is there a more toxic thread anywhere?  Cause if so I'd love to get in on that shiit ...

Why the moderator allows the name-calling and on-going general jackassery only he and Jude know, but maybe it's because it makes for a good show for us broken toys.

You gotta admit it's a guilty pleasure (not for bigshot of course, this is all he has, but let's let him have something)



Brooko said:


> Thirdly - *how could a cable possibly have a sound signature*?



And also, how could it possibly not?  We don't know either way - sure, we all have opinions based on conjecture, assumptions, and speculation - but speculative opinions aren't science facts, right?   (<-- this is where people usually start resume preening and whining, "but _*my*_ speculation *is* science!")

And in this specific case, despite this giant thread of the arsehole debate club, not once has anyone ever produced any proof one way or another.  That's pretty surprising, right?

I mean it ain't like we're trying to find the Higgs boson here, it's just an electrical transmission encoded & decoded with software that some humans wrote.

And USB audio works pretty good, so the engineers who develop on it every day probably test it a bunch and would have some pretty good proof ... so why not just get that data or, hell, just get a few of those original coders to tell us?

Why has nobody ever actually produced proof the wire can't affect sound quality?   Could be that it doesn't exist.  Maybe it does.  Do you have proof beyond conjecture and guesswork?

I've never seen any, but if you have, please share the data.


----------



## Redcarmoose (Dec 1, 2018)

Brooko said:


> You lost me here.  What difference could "burn-in" possibly have on a wire - no capacitors, no electronics, just wire and solder .........
> 
> And why 200 hours?  Where is the science behind the time?
> 
> Thirdly - how could a cable possibly have a sound signature?  It's wire.  Even different capacitance won't make difference because its between components, so things like impedance can't come into play.  Again - if all its conveying is a digital signal, how can it affect analog output (ie frequency response)?



It’s the old burn-in theory. You and I right............ we both have been around for awhile. 12K in posts, it’s really unproven. Though companies do state best results after burn-in. Woo Audio suggests owners burn-in their tube amps.

I’m here to get an education about USB cables, I will also post whatever I find to be true. Also I have no proof about burn-in either.

But.....

I do know the cheep USB cables have been used; they have hours on them, so I’m trying to level the playing field and make the prior test differences closer. Best case plan may be all cables new in box. But also there are people who believe burn in changes sound. So another best case could be all 4 cables new in box, burned-in 200 hours.

200 hours is just a random burn-in amount. I have heard what I have thought was burn in but when tested side by side against new they were the same sounding headphones in one test, so it may have been 100% brain burn in. Brain burn in is a concept I do believe as it’s commen for perception to start gaining detail knowledge after repeated exposure to something perceived. You look out across a valley in 30 seconds notice only so much. Spend 6 hours and you notice different trees, other rocks, how the different far away details start to look, and so on. I’m pretty sure it’s common sense that the more someone studies something the more they get acquainted. Thus when you return you know what to look for.


How could a cable have a sound signature. Well this is SS and the question as been burning out monitor pixels for over a decade here, so I am not going to go into copper and silver traits, as it’s slightly off topic, and I’m over it.

But as far as the Carbon USB having a signature in sighted tests, it does. That signature remains consistent. If it’s because it’s $170....maybe? If it’s placebo.....maybe? But that is what my blind test is for.

But no I’m not letting my gear out to some independent  testing facility. I have done, and I am planning other tests for my own study. I’m simply stating that this is what works for me. We already talked about the large variables which cause the test and purchase of an expensive USB cable being of different results depending on the application and owner.

If I end with negative results I hope it would help people to forget about waisting their time. If I have positive results it could help people to do their own tests. Outside of SS, that’s the main function of Head-Fi besides advertising; it ends up as value for place of reference. Still it’s not till people get home and apply what is learned or speculated that proof is obtained.

But the reason I would not give my cables from the test out is I would not want my Carbon USB damaged.

Funny to note also, we are not ever reading about most of the people here doing any style of tests. It seems their opinions are cast and they have nothing more to learn. They are fully opinionated to the point of cement. I’m saying I know nothing.

But in sighted tests the Carbon USB takes and changes the signature. It could be color, as always when treble is increased it can result in the perception of added detail, and added detail can subjectively sound like brighter treble (color).


----------



## bigshot (Nov 30, 2018)

It was 70% on the cheap cables. The more expensive ones were 100%. He thinks that makes the expensive cables sound better. It indicates the exact opposite, but he doesn't understand the basic concepts enough to realize it.

It's obvious he lis prevaricating.


----------



## Redcarmoose

bigshot said:


> It was 70% on the cheap cables. The more expensive ones were 100%.



Thank-you, I will have to go back. So 100% of the time he could differentiate the expensive from the low cost.


----------



## bigshot

Yes, which would indicate that the expensive ones are the ones that are colored, not the cheap ones. But he isn't bright enough to realize that. Unique means colored. Everything the same means audibly transparent.


----------



## GrussGott (Nov 30, 2018)

bigshot said:


> It was 70% on the cheap cables. The more expensive ones were 100%.



Nope, it was 70% across the board (which was just an arbitrary number I made up so my wife would let me spend money.  chicks, amiright?) ... but for clarity, even if it was 100% every time with every cable in existence, it still wouldn't prove shiit.  It's just some informal fecking around I did this one time, although I appreciate bigshot elevating it to solving time travel.

See, I'm not making any claims other than what my experience was.   I'm not a digital signals processing scientist and nobody should buy a spendy USB cable unless they can try it risk-free and they definitely shouldn't take my experience as predictive for them.  See?  No claims whatsoever in there.

I post here purely to provide a counterpoint to your bogus information of speculation stated as facts.

And your antics make me laugh - are you seriously this obsessed over a leisure hobby detail??  That's pretty astounding.

You and this thread are a fascinating anthropology discovery.

Which is science!


----------



## Redcarmoose (Nov 30, 2018)

bigshot said:


> Yes, which would indicate that the expensive ones are the ones that are colored, not the cheap ones. But he isn't bright enough to realize that. Unique means colored. Everything the same means audibly transparent.



Why are you calling someone a name. We are not on the playground in 5th grade here. I’m saying that in sighted tests the Carbon USB cables have more detail also which makes them sound both bright and have an expanded soundstage. They also have better bass detail. More clear.

At times more clear can seem like color. And color can seem like more clear.......100% of this is subjectivism here of course.


----------



## Redcarmoose

GrussGott said:


> Nope, it was 70% across the board (which was just an arbitrary number I made up so my wife would let me spend money.  chicks, amiright?) ... but for clarity, even if it was 100% every time with every cable in existence, it still wouldn't prove shiit.  It's just some informal fecking around I did this one time.
> 
> See, I'm not making any claims other than what my experience was.   I'm not a digital signals processing scientist and nobody should buy a spendy USB cable unless they can try it risk-free and they definitely shouldn't take my experience as predictive for them.  See?  No claims whatsoever in there.
> 
> ...



That was my impression 70% across the board.


----------



## GrussGott (Dec 1, 2018)

Redcarmoose said:


> That was my impression 70% across the board.



Yeah, but @bigshot should spend a few hours putting together a compendium of all of my posts.

course bigshot probably has bigger fish to fry like someone on the internet is arguing over how many beans are in the jar and he's got to set them straight.

Bigshot has important scientific things to do!

All we can really do is hope he gives us a chance.


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## bigshot (Dec 1, 2018)

Redcarmoose said:


> Why are you calling someone a name.



Because I interacted with him long enough to determine that he was disingenuous. He wants us to accept his word without proof, and when offered the opportunity to help us verify his "test" he ignored me. When he couldn't ignore me any longer, he started telling me his conclusion. He didn't provide evidence that what he was saying is true.

People can come into a forum and claim whatever they want. He says that this "test" was performed long ago. But he has participated in this forum on this subject for the better part of a year without ever mentioning this "test".

If he wants me to consider his claim, he can help me try to verify it, not make excuses. I've heard that too many times before from people who claim things that don't appear to follow the laws of physics.


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## Redcarmoose

GrussGott said:


> Yeah, but @bigshot should spend a few hours putting together a compendium of all of my posts.
> 
> course bigshot probably has bigger fish to fry like someone on the internet is arguing over how many beans are in the jar and he's got to set them straight.
> 
> ...



And I became slightly altered from normal composure due to his asking for more tests. But truly the less we can have name calling and emotional disputes here, the faster we can get to the truth.


----------



## Redcarmoose

@https://www.head-fi.org/members/bigshot.17990/

Yes, but even though this thread is what it is, there is nothing like it on Head-Fi. And ....  if not locked over egotistic silliness; it could actually be of use.


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## bigshot (Dec 1, 2018)

ABSOLUTELY! But encouraging people who can't engage in fair discourse won't make it useful. This is a big problem in this forum and until people demand better and raise the bar themselves, that will never happen.


----------



## Brooko

Redcarmoose said:


> It’s the old burn-in theory. You and I right............ we both have been around for awhile. 12K in posts, it’s really unproven. Though companies do state best results after burn-in. Woo Audio suggests owners burn-in their tube amps.



Tube amps aren't straight wire though - they do require warming up, and when first used take some time to get to a consistent state.  There is a measurable difference with tubes - so its not the same thing.  Same goes for capacitors.  Straight wire though - I've searched and there  is no evidence of change in wire via break-in / burn-in, at least nothing that would pass scientific muster.  Plenty of anecdotal stuff based on sighted comparison - which we all know is not evidence.



Redcarmoose said:


> 200 hours is just a random burn-in amount. I have heard what I have thought was burn in but when tested side by side against new they were the same sounding headphones in one test, so it may have been 100% brain burn in. Brain burn in is a concept I do believe as it’s commen for perception to start gaining detail knowledge after repeated exposure to something perceived. You look out across a valley in 30 seconds notice only so much. Spend 6 hours and you notice different trees, other rocks, how the different far away details start to look, and so on. I’m pretty sure it’s common sense that the more someone studies something the more they get acquainted. Thus when you return you know what to look for.



Actually no - all brain burn-in denotes is that you've listened to something before, and once you have your brain compensates each subsequent time you listen.  Its why our perception changes, and its our brains at work - and why we can't rely on straight senses for real accuracy.  Take this example. I have a pair of Alessandro MS Pros (think equivalent Grado RS1) and a pair of HD600s.  Both have been "broken in" (if you believe that) - both have had literally 100's of hours of use.  If I listen to the MS Pros - when I first start listening they appear aggressive, sharp, with narrow staging, slightly anaemic bass, and very coloured mid-forward signature.  After 30 minutes, they are less sharp, bass response is good, they are detailed clear and incredibly fun.  Switch to the HD600s and they seem slow, warm, very expansive (in comparison), with quite loose and slightly flabby bass, and an almost veiled treble response.  Give it 30 minutes with them and they become tonally accurate with great timbre and texture, very natural sounding, bass now seems normal etc etc.  Switch back to the MS Pros and rinse and repeat.

Has either headphone changed?  No.  What has changed is my subjective impression of them relative to what I have been listening to.  That is the power of the brain, and one of the reasons we can't trust ourselves when we are looking at making proper reasoned suppositions.



Redcarmoose said:


> How could a cable have a sound signature. Well this is SS and the question as been burning out monitor pixels for over a decade here, so I am not going to go into copper and silver traits, as it’s slightly off topic, and I’m over it.But as far as the Carbon USB having a signature in *sighted tests*, it does. That signature remains consistent. If it’s because it’s $170....maybe? If it’s placebo.....maybe? But that is what my blind test is for.



I'm pleased you are doing the blind-test because as soon as you bring in sight, or any kind of bias, your brain includes that in its decision making.  Its extremely well documented, and why we refer to placebo as being very powerful.  The first 10 minutes in Ethan Winers Audio Myth Workshop is really good as examples of how placebo affects us and why the gold standard in scientific testing has always been a blind test.  I'll look forward to yours.  Please document the actual set-up when you do it, including how they were swapped, number of tests, how you controlled the level of randomness etc (eg there should be instances when the same cable appears twice or more in a test round).  And please make sure that the listening environment is strictly controlled - including checking volume matching etc.


----------



## Brooko (Dec 1, 2018)

GrussGott said:


> And also, how could it possibly not?  We don't know either way - sure, we all have opinions based on conjecture, assumptions, and speculation - but speculative opinions aren't science facts, right?   (<-- this is where people usually start resume preening and whining, "but _*my*_ speculation *is* science!")
> 
> And in this specific case, despite this giant thread of the arsehole debate club, not once has anyone ever produced any proof one way or another.  That's pretty surprising, right?
> 
> ...


https://www.edn.com/electronics-blogs/rowe-s-and-columns/4421042/Can-You-Hear-the-Difference-

The guy does this for a living and fully understands the USB protocol.  There are many more articles like this all over the net from experts who absolutely understand what is going on.  He has a series on the USB protocol and how it works.  I've read some of them.  Instead of all the "well nobody really knows" arguments, try researching the guys who do this for a living.  Because they really do know.


----------



## WoodyLuvr (Dec 1, 2018)

Redcarmoose said:


> @https://www.head-fi.org/members/bigshot.17990/
> 
> Yes, but even though this thread is what it is, there is nothing like it on Head-Fi. And ....  if not locked over egotistic silliness; it could actually be of use.


I have to agree with @Redcarmoose... let's simply just stick to the subject at hand and completely remove the emotion and personal pettiness from the thread and our posts... as I too believe the current topic is of great interest to many.

I completely understand the frustration that many may feel but two wrongs don't make a right... fighting fire with fire is not helpful in this type of format... throwing fuel on the flames with vengeful retorts is getting us nowhere fast... we have been all caught up in a vicious cycle so let's break out of it.

*Hence forth EVERYONE posting on this thread please kindly refrain from "name calling", "baiting", "personal attacks", and other such obvious "clownery" that incites emotional responses from others. *Let's be more open to other's perspectives; be willing to thoughtfully reflect on issues especially those we disagree with; and learn to entertain, the even remote possibility, that others may be right and/or have something worthy to offer.

If and when emotional, clownish, and/or personal attack posts appear let us all agree to simply ignore them and the poster completely until they "get the picture" and conform to the civility that we are demanding and expect in Sound Science. Really, simple as that. Why can't we implement this, we are all adults, some very old ones at that, correct?


----------



## Redcarmoose (Dec 1, 2018)

Also you have to realize, I’m not probably emotional about this subject. I already purchased my cable; there is no way to return it regardless of the test outcome.

It has been noted that “the cause” can be the single greatest motivation for humans. This may go super far back in our origins; where humans were emotionally aligned in battle. “The Cause” can rule over almost anything in human emotions. So you have the pro-cause and anti-cause.

It’s the reason why comments get taken personally and create drama. Science is full of it anyway. And........I’m not calling anything here truly scientific, I’m farthest from a scientific person. But you have to remember, in the history of science, any big discovery was met with hostility.

Why? Because it questioned standard acceptable ideas of reality.


----------



## bigshot (Dec 1, 2018)

I am emotional about the sorry state of this forum. I couldn't care less about USB cables. We need to raise the level of discourse around here. That requires dismissing illogical, ignorant, disingenuous and flat out wrong opinions and not encouraging stuff like that to be posted. All opinions are not created equal. People who refuse to back up what they claim should be called out on it. Go back and look at the chronology of the posts. I was patient, helpful and encouraging up until the point where it was blatantly obvious that the truth wasn't what he was after. Don't jerk me around and I'll be a *****cat. I'll even help you figure things out. Try to ram through BS and I'll call you out on it loudly.


----------



## Redcarmoose (Dec 1, 2018)

bigshot said:


> I am emotional about the sorry state of this forum. I couldn't care less about USB cables. We need to raise the level of discourse around here. That requires dismissing illogical, ignorant, disingenuous and flat out wrong opinions and not encouraging stuff like that to be posted. All opinions are not created equal. People who refuse to back up what they claim should be called out on it. Go back and look at the chronology of the posts. I was patient, helpful and encouraging up until the point where it was blatantly obvious that the truth wasn't what he was after. Don't jerk me around and I'll be a *****cat. I'll even help you figure things out. Try to ram through BS and I'll call you out on it loudly.



So your here to police the methodology and intent of the posters. I believe his honesty......but I bet you two would become good buddies if we could get you both off this subject. I bet you both have much in common.


----------



## Steve999

Come on, the answer to why do usb cables make such a difference is “they don’t.” Kill the thread.


----------



## Redcarmoose

Steve999 said:


> Come on, the answer to why do usb cables make such a difference is “they don’t.” Kill the thread.



Prove it, and this thread can be closed.


----------



## Steve999

Redcarmoose said:


> Prove it, and this thread can be closed.



No you prove one usb cable makes a difference. Then you can kill the thread.


----------



## bigshot (Dec 1, 2018)

If you don't like my posts, it is very easy to not read them. I assure you there are posters whose posts I don't read.

I'm looking for a USB cable that sounds clearly different under controlled listening tests. If you  have one one, I'll certainly listen. But I'm not interested in unsubstantiated claims or excuses.


----------



## Steve999

bigshot said:


> If you don't like my posts, it is very easy to not read them. I assure you there are posters whose posts I don't read.



I read everything.


----------



## bigshot

You should think about being more discerning with your attentions.


----------



## Triode User

Oh, dear. What just happened after I went to bed then got up this morning?

Anyway, I earlier put forward a hypothesis about why different usb cables might make a difference to the sound. It quickly got the standard sound science mantra of show us numbers before we can discuss it. I thought the way science worked was that one had a hypothesis which was discussed and *then *one set about putting numbers to it to upgrade it to a theory which was then proved or otherwise. You guys seem to want the proof before you will discuss it.


----------



## Redcarmoose

Steve999 said:


> No you prove one usb cable makes a difference. Then you can kill the thread.



Yes, I will attempt to learn what’s up here. I’ve been surprised in the world of audio often.


----------



## Steve999

Triode User said:


> Oh, dear. What just happened after I went to bed then got up this morning?
> 
> Anyway, I earlier put forward a hypothesis about why different usb cables might make a difference to the sound. It quickly got the standard sound science mantra of show us numbers before we can discuss it. I thought the way science worked was that one had a hypothesis which was discussed and *then *one set about putting numbers to it to upgrade it to a theory which was then proved or otherwise. You guys seem to want the proof before you will discuss it.



We’re on page 93 and post 1382. That’s not enough?


----------



## Steve999

I read fast.


----------



## Triode User

Steve999 said:


> We’re on page 93 and post 1382. That’s not enough?



But nowhere else in the thread that I recollect was a similar hypothesis to mine put forward and discussed. 

Or are you meaning that you think the content of the thread demonstrates a consistent unwillingness to discuss hypotheses and I should have realised that before venturing one?


----------



## Redcarmoose

I can only offer one highly illogical and subjective truth. 


If you have my exact same equipment, and you are actually me; if you change to the AQ Carbon, you will notice a sighted and profound improvement every time you listen. 



The true value of this individual post is up for debate.


----------



## Brooko

Triode User said:


> Oh, dear. What just happened after I went to bed then got up this morning?
> 
> Anyway, I earlier put forward a hypothesis about why different usb cables might make a difference to the sound. It quickly got the standard sound science mantra of show us numbers before we can discuss it. I thought the way science worked was that one had a hypothesis which was discussed and *then *one set about putting numbers to it to upgrade it to a theory which was then proved or otherwise. You guys seem to want the proof before you will discuss it.



I read your hypothesis, and I'm afraid the one thing I don't get is this.  If there is an issue with HF noise in the digital signal, under error checking the USB protocol will reject, and will result in dropped packets. So the DAC experiences drop-outs.  For RF noise to have an audible effect (ie changing frequency or timing), surely it would need to affect the analog stage - because for the effects you put forward (harshness etc), the USB cable cannot possibly cause these pre-conversion in the DAC.  I posted this link earlier - https://www.edn.com/electronics-blogs/rowe-s-and-columns/4421042/Can-You-Hear-the-Difference-
Martin is an EE with extensive knowledge of USB (easy to look up his credentials - https://www.linkedin.com/in/measurementblues/)

As you stated earlier - differences with BNC cables were easily audible, and changes were "no harshness".  If this is so, it must be measurable.  Can you please measure these easily heard changes, so we can compare the digital outputs, and that would make a good place to start further debate.


----------



## Steve999 (Dec 1, 2018)

Redcarmoose said:


> I can only offer one highly illogical and subjective truth.
> 
> 
> If you have my exact same equipment, and you are actually me; if you change to the AQ Carbon, you will
> ...



I’m not ignoring you, I’m just at a loss as to what to say.


----------



## Brooko

Redcarmoose said:


> I can only offer one highly illogical and subjective truth.
> If you have my exact same equipment, and you are actually me; if you change to the AQ Carbon, you will notice a sighted and profound improvement every time you listen.
> The true value of this individual post is up for debate.



So then the answer to the original thread question - "why do USB cables make such a difference" can be summarised that the difference exists in the imagination of the individual.  Because that is essentially what has happened.  In your sighted tests, you have introduced expectation bias, and that is why you "hear" a difference.  Because your brain has coloured the output.  And that's fine if you are happy with that.  But being in Sound Science - the question we want to know is if there is a real audible and measurable change - with the emphasis on *real* and the expectation that the output should be both *audible* and *measurable*.  Hint here - if it is actually audible, it will be measurable.

I totally accept that you hear it - ie audible to your perceptions.

Yet to prove - is it measurable, and is it actually real?


----------



## Redcarmoose

Brooko said:


> So then the answer to the original thread question - "why do USB cables make such a difference" can be summarised that the difference exists in the imagination of the individual.  Because that is essentially what has happened.  In your sighted tests, you have introduced expectation bias, and that is why you "hear" a difference.  Because your brain has coloured the output.  And that's fine if you are happy with that.  But being in Sound Science - the question we want to know is if there is a real audible and measurable change - with the emphasis on *real* and the expectation that the output should be both *audible* and *measurable*.  Hint here - if it is actually audible, it will be measurable.
> 
> I totally accept that you hear it - ie audible to your perceptions.
> 
> Yet to prove - is it measurable, and is it actually real?


Yes. This is the best post maybe in a week here..........to me.


----------



## gregorio

Triode User said:


> [1] USB being balanced will not help prevent it picking up the noise I am discussing because much of it is created by the audio device creating the digital signal.
> [2] It is possibly not an issue with many systems because they might mask the problem sound and as I mentioned
> [3] Design digital sources need to be quieter with respect to the noise they have in their digital circuits.
> [4] The USB cable only needs to comply with the USB transfer standards in order to work properly in terms of digital transfer.
> ...



1. In which case the USB cable is not "picking up the noise" it is simply transferring what it's being given.

2. It's also often not an issue with many systems because many systems do not produce enough noise to be audible in the first place and even when that isn't the case, even cheap ($80) DACs manage to isolate their analogue section from source noise to levels far below audibility. So are you saying that audiophile DACs can't manage noise leaking into their analogue sections as well as cheap DACs?

3. Why and how? If the source is a computer, then there's going to be significant noise, from the CPU, hard-disks, GPU, etc., suppressing the noise from each of these components within a computer would be a big and expensive task. A DAC which is designed to be connected to a computer obviously needs to address the fact that computers always produce noise and some of it will find it's way into the computer's USB output and it's obviously not particularly difficult or expensive to address this fact as cheap units easily manage it.

4. Correct. 
4a. No, the question would be: Is there audible noise leaking into the analogue section of a DAC in the first place and if so, is the DAC faulty or just incompetently designed?

5. Where? What apart from numbers do you think there is in digital audio? Even the analogue electrical signal is just numbers, as proved by Maxwell over 150 years ago.



GrussGott said:


> [1] Why has nobody ever actually produced proof the wire can't affect sound quality?
> [1a] Do you have proof beyond conjecture and guesswork?
> [2] I'm not a digital signals processing scientist and nobody should buy a spendy USB cable unless they can try it risk-free and they definitely shouldn't take my experience as predictive for them. See? No claims whatsoever in there.
> [3] I post here purely to provide a counterpoint to your bogus information of speculation stated as facts.
> ...



1. No one has said that cables can't affect sound quality. Analogue audio cables do affect the electric signal, just nowhere near enough to be audible. However, that's not relevant to USB cables because USB cables do not carry any sound in the first place!
1a. Sure, there's even a thread in this forum going back about a decade, which shows that different analogue cables affect the electrical signal by only a few thousandths of a dB and there's copious amounts of proof/evidence that this is way below audibility. Look-up for example the ABX protocol, which stipulates volume matching to a tenth of a dB, as that was found to already be below audibility and therefore would not affect the test results.

2. So you're not a digital signals scientist/expert but you CLAIM "nobody should buy a spendy USB cable unless they can try it" and then you say "no claims whatsoever in there"? Your antics make me laugh!!

3. So hang on, you don't claim to be an expert, you obviously don't know the facts (as demonstrated by the fact that you are denying there is any evidence/proof when in fact there's loads) but you're going to counterpoint the information here anyway. On what basis, that you don't know the science/facts and therefore you can make-up anything you want?

4. If you bothered to learn some facts and then looked in the mirror, maybe you'd stop laughing and instead be embarrassed? Until you do, we'll just have to laugh at your antics!
4a. It's not just a leisure hobby, for some it's what we do for a living or do you think the entire recording industry (and the science behind it) is just a hobby?? That's pretty astounding!

Are you just going to ignore these refutations again, carry on posting bogus information and falsely accuse others of doing exactly what you yourself are doing? 



Redcarmoose said:


> [1] Funny to note also, we are not ever reading about most of the people here doing any style of tests.
> [2] It seems their opinions are cast and they have nothing more to learn. They are fully opinionated to the point of cement. I’m saying I know nothing.
> [3] How could a cable have a sound signature.
> [3a] Well this is SS and the question as been burning out monitor pixels for over a decade here ...



1. That's not true, I've done tests and I've discussed them in this very thread!
2. It's fine for you to say you "know nothing" BUT it's NOT fine to say that just because you know nothing that everyone else must also know nothing and are therefore wrong to be opinionated about it. I've seen the evidence; my own and the scientific and engineering evidence, plus I have a pretty decent knowledge of how digital audio works and I've NEVER seen a single ounce of reliable evidence to the contrary. It's for this reason that I'm "opinionated" about it, which is exactly the same reason that I'm opinionated about gravity existing and the Earth not being flat.

3. Obviously a USB cable can't have a sound signature, because USB cables do not carry any sound!
3a. No it hasn't, there is no question here in SS. The "question" as you put it, is brought here by those who "know nothing" (except maybe for some marketing BS) and then SS has to repeat the same facts and logic all over again, just as it has for over a decade! Clearly though, some people are not interested either in the facts or in employing any logic, which begs the question of why they come to SS in the first place?

G


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## Redcarmoose (Dec 1, 2018)

@https://www.head-fi.org/members/gregorio.69811/

“Clearly though, some people are not interested either in the facts or in employing any logic, which begs the question of why they come to SS in the first palace?”


I hope you don’t mind taking your quote slighly out of full context here? I truly don’t know about USB cables and that’s why I’m here. I will find your tests. Thank-you.


----------



## gregorio

Triode User said:


> I thought the way science worked was that one had a hypothesis which was discussed and *then *one set about putting numbers ...



Ah, then you're mistaken because that is not the way that science works! A hypothesis MUST have some logical and scientific basis to start with, say some proven maths/physics which implies or indicates the hypothesis. A hypothesis is not just any idea that anyone dreams up without any evidence, and it's certainly NOT just any old dreamt-up idea without any supporting evidence of it's own that ALSO CONTRADICTS all the existing facts/science/evidence! If that were "the way science worked", then science would spend all it's time "discussing and setting about putting numbers on" unicorns, flying pigs, mermaids, faeries and anything else that anyone could dream-up and it wouldn't have any time left to do any actual science!

A large part of why this thread (and many others here) goes round and round in circles is not just because people don't know the specific science involved (which is understandable) but because they don't even seem to know the fundamental basics of how science works. One can't just assume that because they don't know the science/facts then the facts/science doesn't exist and even if the science/facts didn't exist (which they do) then STILL you can't just make-up anything you want and claim it's a hypothesis (or in anyway factual). In other forums you certainly can but in this forum you're going to be called out on it if you do, and will be considered a nutter or a troll if you refuse to provide any reliable supporting evidence and just keep repeating the claim/"hypothesis".

G


----------



## jagwap (Dec 1, 2018)

Triode User said:


> Oh, dear. What just happened after I went to bed then got up this morning?
> 
> Anyway, I earlier put forward a hypothesis about why different usb cables might make a difference to the sound. It quickly got the standard sound science mantra of show us numbers before we can discuss it. I thought the way science worked was that one had a hypothesis which was discussed and *then *one set about putting numbers to it to upgrade it to a theory which was then proved or otherwise. You guys seem to want the proof before you will discuss it.



I think I put forward a similar hypothesis many pages ago, but it was treated similarly. I'm not going to trawl through all this to find it or the details. I agree that *if* there there is a difference between USB cables, the primary reason is likely RF. Like you I didn't suggest corrupted data, but interference in the DAC conversion and analogue circuits. However that was ignored I think by those how do not want to hear alternative possibilities.

Nothing is entirely immune to RF. A cable's length can resonate at different frequencies as an antenna just on its sheild braid. A source (RF noisy PC) a cable and a DAC are a system,and in EMC terms need to be treated as such. All of them contribute to the overal result.

The problem here is the fence between standpoints and no one is prepared to move to the middle and knock the fence over.

Bigshot thinks everthing digital related sounds the same, and doesn't realise there is analogue in digital equipment. If you send him cables I find it unlikely he will try to hear a difference. He is not open to the idea.

Gregorio thinks pro audio equipment is better than consumer, because they only measure it, never listen to it. This is the exact reason why much consumer equipment can be better that pro gear. But of course, not always.

I've worked in both sides of the industry, pro and consumer, and I dispare at the pro sides lack of listening tests outside of accoustic equipment. Equally I dispare the audiophile industry's reliance on voodoo. Both could learn from each other.

Final point. If the USB system is asynchronous, i.e. XMOS, TI or CMedia done right, and the DAC clock is the master, the cable CANNOT add jitter. It is not lost data. It is not unobtainium. It is most likely the RF interaction of the whole system causing interference in the analogue sections of the audio circuitry. This could get all the way to the power amps, where the PN junction of the input stage can demodulate the RF into audio. Edit: so can the PN junctions in the cheap opamps in DACs. JFET input opamps are reassuring in this area, but more than pro is prepared to spend.


----------



## Triode User

jagwap said:


> I think I put forward a similar hypothesis many pages ago, but it was treated similarly. I'm not going to trawl through all this to find it or the details. I agree that if there there is a difference between USB cables, the primary reasin is likely RF. Like you I didn't suggest corrupted data, but interference in the DAC conversion and analogue circuits. However that was ignore I think by those how do not want to hear alternative possibilities.
> 
> Nothing is entirely immune to RF. A cable's length can resonate at different frequencies as an antenna just on its sheild braid. A source (RF nkisy PC) a cabke and a DAC are a system,and in EMC terms need to be treated as such. All of them contribute to the overal result.
> 
> ...



Ah, someone talking sense and in a reasonable way. I think you and I are more or less aligned in what we are suggesting. My demonstrations of the effect of BNC cables which filter RF noise are so obvious that anyone who hears them is in no doubt that there is a big difference. It is a bit like the change when someone alters the treble on an old tone control. No one ever asked to be shown the numbers on tone controls before they believe what they were hearing. The difference in the sound is enough to convince them that they work. Sure, at a theoretical level some people might like to attach numbers to satisfy themselves but numbers are not always needed when the difference is that big. 

Anyway, I have had one sensible response and I thank you for your time in responding. I will go away and have a play with making some USB cables similar to my BNC cables and see what happens. You will know it has worked if you see my adverts in the HFi magazines.


----------



## Brooko

So because anyone else’s questions don’t match your hypothesis you ignore them?

How hard is it to measure the output of the signals using different cables?  If there is no difference, there is your answer.


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## Redcarmoose (Dec 1, 2018)

I remember getting into EMF paper wrapped cables about 9 years ago. After doing some Google searches then there was some but not an amazing amount of research.

A short Google search now shows an abundance of interest in the suppression of EMF. We now have EMF wallpaper for your house, and you could completely enclose your listening room from external EMF.

As a general guide it seems the upper AQ USB cables all tout EMF shielding, though it seeems a rare subject to test EMF on data transfer. It has come from small pieces of paper being vary expensive to people covering their walls with the stuff. Also noted this year are fashionable science papers depicting EMF on the human organism.

EMF has now become the buzz word for equipment enclosure too, as it looks to be the ultimate audiophile bogeyman now-a-days.


----------



## Arpiben

Brooko said:


> So because anyone else’s questions don’t match your hypothesis you ignore them?
> 
> How hard is it to measure the output of the signals using different cables?  If there is no difference, there is your answer.



It is not hard at all to measure. People involved in cable business are for obvious reasons not prone to publish such measurements.


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## Don Hills

Redcarmoose said:


> ... A short Google search now shows an abundance of interest in the suppression of EMF. ... .





Without EMF, there would be no signal.Maybe you mean EMI?


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## Redcarmoose (Dec 1, 2018)

Electromagnetic Fields or Electromagnectic Interference. Haha your right. But they call it EMF paper at least they used to and still do in some circles; simply nomenclature details. Could be the audiophile equivalent of slang?


Don Hills said:


> Without EMF, there would be no signal.Maybe you mean EMI?


----------



## Arpiben

Redcarmoose said:


> I remember getting into EMF paper wrapped cables about 9 years ago. After doing some Google searches then there was some but not an amazing amount of research.
> 
> A short Google search now shows an abundance of interest in the suppression of EMF. We now have EMF wallpaper for your house, and you could completely enclose your listening room from external EMF.
> 
> ...



Excepting few of us we are all surrounded by thousands of devices generating EMF. The number of such devices will increase exponentially in the coming years.
Manufacturers do play with people fears even if all this accounts for 0.0001 dB in the main cases.


----------



## Redcarmoose (Dec 1, 2018)

Don Hills said:


> Without EMF, there would be no signal.Maybe you mean EMI?


https://www.amazon.com/MAGNETIC-SHIELDING-Shielding-Magnetic-Fields/dp/B00NMS67X
It’s the stuff placebo cigarettes are rolled with. There is also ERS paper.

http://www.tnt-audio.com/accessories/ers_cloth_e.html

Anything someone will throw a dollar at.


----------



## Arpiben

jagwap said:


> I think I put forward a similar hypothesis many pages ago, but it was treated similarly. I'm not going to trawl through all this to find it or the details. I agree that *if* there there is a difference between USB cables, the primary reason is likely RF. Like you I didn't suggest corrupted data, but interference in the DAC conversion and analogue circuits. However that was ignored I think by those how do not want to hear alternative possibilities.
> 
> Nothing is entirely immune to RF. A cable's length can resonate at different frequencies as an antenna just on its sheild braid. A source (RF noisy PC) a cable and a DAC are a system,and in EMC terms need to be treated as such. All of them contribute to the overal result.
> 
> ...



Let us take DAC case. It is not difficult to measure its susceptibility to DC/AC/ground noises. It is not difficult to measure its susceptibility to EMI/RFI with cables connected or not. 
 In principle those effects should be insignificant when translated into output audio levels. Now in case it is not one can easily measure the differences.
For obvious reasons no manufacturer will start publishing such values if competitors don't do or any organism forces them to do.

You raised quite correct points in your post. Nevertheless I do adhere to @bigshot and @gregorio  approach in the sense that one should look at it widely ( general cases ) and not at exceptions.
EMI/RFI is not a topic everyone is dealing everyday with and it is quite easy to afraid or provide unclear information to  listeners.

Despite the fact I once worked with those aspects in terms of components susceptibility versus Electromagnetic Waves, I have no better idea about how is it really when dealing with Audio items.
Since the power needed to interfere must be quite high I am doubtful until I am provided with null tests / output measurements / etc....

Anyhow a cable change is not the solution for tackling eventual issues. The first step is to identify the 'noise' source in case of any instead of adding band straps everywhere  with more or less luck.


----------



## WoodyLuvr

jagwap said:


> Nothing is entirely immune to RF. A cable's length can resonate at different frequencies as an antenna just on its sheild braid. A source (RF noisy PC) a cable and a DAC are a system,and in EMC terms need to be treated as such. All of them contribute to the overal result.


Computers sure can be noisy... very curious if this may or may not shed some light on why some perceive an audible difference in their usb cables though I do find myself leaning towards what *@Brooko* has so nicely proposed.


Brooko said:


> So then the answer to the original thread question - "why do USB cables make such a difference" can be summarised that the difference exists in the imagination of the individual.  Because that is essentially what has happened.  In your sighted tests, you have introduced expectation bias, and that is why you "hear" a difference.  Because your brain has coloured the output.  And that's fine if you are happy with that.  But being in Sound Science - the question we want to know is if there is a real audible and measurable change - with the emphasis on *real* and the expectation that the output should be both *audible* and *measurable*.  Hint here - if it is actually audible, it will be measurable.
> 
> I totally accept that you hear it - ie audible to your perceptions.
> 
> Yet to prove - is it measurable, and is it actually real?


----------



## GrussGott

gregorio said:


> So you're not a digital signals scientist/expert but you CLAIM "nobody should buy a spendy USB cable unless they can try it" and then you say "no claims whatsoever in there"?


FYI, that's what most people recognize as a common sense recommendation Greg.  Just so you know in case  you ever run across those again.



gregorio said:


> A hypothesis MUST have some [deleted wrong part] scientific basis to start with, say some [deleted wrong part] maths/physics which implies or indicates the hypothesis.



Uh huh, so if everyone here prefaced their comments with, "I have an hypothesis ..." and concluded with, "... however I have no data showing that's globally true" we'd be good!

Because speculation, no matter its basis (or the size of ego presenting it), isn't science, it's just guesswork.  I understand why you're tempted to believe otherwise, but ask anyone who works in a field where misses kill people and they'll point you to the regulations that govern their work which basically say it's proven with data or it's speculation.

Maybe if we were all polite and humble enough to preface our speculation this thread wouldn't suck ...

... But in today's crazy mixed up world, asking for a little humility seems too big of an ask.


----------



## JRG1990

Objective data shows theres no audible differences between usb cables, http://archimago.blogspot.com/2013/04/measurements-usb-cables-for-dacs.html .

Even with a poorley designed dac highly sensitive to power and USB conditions the cable has a larger effect but still not audible https://www.audiosciencereview.com/...s/do-usb-audio-cables-make-a-difference.1887/ .

I have yet to find any measurements showing a difference thats even close to audible.


----------



## GrussGott (Dec 1, 2018)

Brooko said:


> So then the answer to the original thread question - "why do USB cables make such a difference" can be summarised that the difference exists in the imagination of the individual.  Because that is essentially what has happened.  In your sighted tests, you have introduced expectation bias, and that is why you "hear" a difference.  Because your brain has coloured the output.  And that's fine if you are happy with that.  But being in Sound Science - the question we want to know is if there is a real audible and measurable change - with the emphasis on *real* and the expectation that the output should be both *audible* and *measurable*.  Hint here - if it is actually audible, it will be measurable.
> 
> I totally accept that you hear it - ie audible to your perceptions.
> 
> Yet to prove - is it measurable, and is it actually real?



Wow, I mostly agree with all of that, I would just rephrase it:

"why do USB cables make such a difference" can be summarised as some people have experienced a difference, others have not, *and there is no data one way or another to prove either case. *(just a lot of, "buy my speculation is really smart sounding and I have a giant needy ego so everyone should just agree")

The science part of this is, when there is observed phenomena, we have to prove why it happened one way or another or we still don't know.*

*Special Fun Related Nerd Topic
I hesitate to bring up the placebo effect because it also seems controversial, but in healthcare the data shows over the last decade the placebo effect is getting stronger with all kinds of drugs (and most that study it speculate the placebo effect isn't one thing, but many different things grouped together under that header).  Nevertheless, double-blind drug trials are showing large increases in the placebo effect which sits at the nexus of biology, psychology, and chemistry (in the case of drugs).  In general placebos seem to relieve the symptoms of an ailment but not the underlying cause.

Now for the really bizarre thing: there are randomized trials showing that some placebos still work even when you tell the person it's a sugar pill!

The ethical question in all of this could be, if a business goes to the trouble of creating a pill or procedure that it says won't cure your underlying condition, but may relieve (or eliminate) symptoms of pain, and it does for many people, is that a legit product?  I'd say yes.

The point is that if hearing is viewed as a condition, and sound qualities as a symptom, then it's likely leisure audio has all kinds of placebo effects going on with all of it, both heard and unheard, and since sound quality is at the nexus of biology and psychology it's probably fruitless to tell someone an experience didn't happen.  Note that even people who are told they're getting a sugar pill still experienced improvements.

What I'm not saying is that USB cables (or any component) are for sure totally completely placebo, but it's possible.


----------



## GrussGott (Dec 1, 2018)

JRG1990 said:


> Objective data shows theres no audible differences between usb cables, http://archimago.blogspot.com/2013/04/measurements-usb-cables-for-dacs.html .
> 
> Even with a poorley designed dac highly sensitive to power and USB conditions the cable has a larger effect but still not audible https://www.audiosciencereview.com/...s/do-usb-audio-cables-make-a-difference.1887/ .
> 
> I have yet to find any measurements showing a difference thats even close to audible.



And also, there's no objective data to say it isn't happening, despite the fact that USB is just an electrical transmission coded and decoded with knowable computer software and presumably oodles of testing.  Despite that, somehow we still don't know one way or another.

So, yes, we have no data to prove anything one way or another.


----------



## Brooko

GrussGott said:


> And also, there's no objective data to say it isn't happening, despite the fact that USB is just an electrical transmission coded and decoded with knowable computer software and presumably oodles of testing.  Despite that, somehow we still don't know one way or another.
> 
> So, yes, we have no data to prove anything one way or another.


Um - did you even read those links? That was objectively measured data which showed no differences. He also listened and heard no differences.  That is a scientific approach - propose, observe, measure. As to your hypothesis that we can’t say if there is a measured difference with other people’s tests - well they keep giving anecdotal evidence, but refuse to measure.  I wonder why?


----------



## GrussGott (Dec 1, 2018)

Brooko said:


> Um - did you even read those links? That was objectively measured data which showed no differences. He also listened and heard no differences.  That is a scientific approach - propose, observe, measure. As to your hypothesis that we can’t say if there is a measured difference with other people’s tests - well they keep giving anecdotal evidence, but refuse to measure.  I wonder why?



I've read those and many many others.  If you think a few tests, in a single environment, with some equipment, and some measurements, taken by a single person, and interpreted by that same person, is conclusive science for all ears, equipment, and environments ... then I guess you do.

Here's the point: USB is just a software-encoded electrical transmission that should be trivial for you to produce that code - the decoding algorithm - which would tell us all of the possible outputs regardless of transmission media.

Why have all the he said / she said junior science debate club stuff?

Just produce the code and testing data and we'd have a conclusion.


----------



## sonitus mirus

GrussGott said:


> I've read those and many many others.  If you think a few tests, in a single environment, with some equipment, and some measurements, taken by a single person, and interpreted by that same person, is conclusive science for all ears, equipment, and environments ... then I guess you do.
> 
> Here's the point: USB is just a software-encoded electrical transmission that should be trivial for you to produce that code - the decoding algorithm - which would tell us all of the possible outputs regardless of transmission media.
> 
> ...



There is a conclusion, and it is that there is no audible difference.  You are simply being trollish and not fooling anyone.


----------



## JRG1990

GrussGott said:


> I've read those and many many others.  If you think a few tests, in a single environment, with some equipment, and some measurements, taken by a single person, and interpreted by that same person, is conclusive science for all ears, equipment, and environments ... then I guess you do.
> 
> Here's the point: USB is just a software-encoded electrical transmission that should be trivial for you to produce that code - the decoding algorithm - which would tell us all of the possible outputs regardless of transmission media.
> 
> ...



You've just dismissed all the objective data supporting theirs no audible difference between usb cables, but haven't provided any that supports your argument that there is.


----------



## Brooko (Dec 1, 2018)

GrussGott said:


> I've read those and many many others.  If you think a few tests, in a single environment, with some equipment, and some measurements, taken by a single person, and interpreted by that same person, is conclusive science for all ears, equipment, and environments ... then I guess you do.
> 
> Here's the point: USB is just a software-encoded electrical transmission that should be trivial for you to produce that code - the decoding algorithm - which would tell us all of the possible outputs regardless of transmission media.
> 
> ...



You asked for objective evidence.  I've linked an example.  What you haven't shown is any objective evidence on the other side.  If you can't, then unfortunately all you're doing is adding noise to the thread.  How about adding some signal.  In the words of Tom Cruise "show me the money".

The only one in this thread who is taking the "junior debate" approach stuff seems to be yourself. Until you start showing some evidence - I'm going to ignore further input from you.


----------



## bigshot (Dec 1, 2018)

I asked him for objective evidence and he made up a story about doing a controlled test. When pressed on his story, he backpedaled and refused to provide any way to verify his findings. He's a thread crapper. He doesn't like what's said in this thread so he's pummeling it with hooey bombs.

There is absolutely no reason to expect that one properly functioning USB cable would sound different than another, regardless of price. But that doesn't mean that high end audio salesmen won't try to make you think that to sell you an expensive cable you don't really need.

I am interested in the possibility of deliberately colored USB cables. If someone knows of a USB cable that sounds clearly different from other USB cables, I would like to  have a chance to test it.


----------



## castleofargh

modo stuff:

@GrussGott. a few pages back you wondered why bigshot was allowed to attack you and others. which is a legitimate question, and mostly the answer is a mix of 2 reasons:
1/ moderators don't read the posts. if someone doesn't behave correctly, you guys can bring the posts to the attention of moderators by reporting them with the dedicated function at the bottom of all posts. so long as that is not done, we tend to assume that everybody's fine. 
2/ yes he attacks you, but you do the same on several occasions. so I either let you guys get it all out of your system, make fools of yourself in front of everybody else, and once it's done we move on. there are already a few pages above all that, today's a new day. 
or I can treat the both of you like kids. go delete many of your respective posts, and start showing the stick to make you behave because I consider you incapable of having a proper conversation and the topic has to get back to following the rules at some point.  

 the section is clearly favorable to disputes, I can't just moderate all of them when most of the time they are the topic. but if after asking a few times for the eternal "argue the points made, not the people making them", and starting to remove more and more posts, people just keep having their personal battles and name calling anyway, my next step is to lock you out. it sucks, and I really don't like doing that(or deleting posts TBH), but if that's what it takes to keep a topic from turning into a street fight, I'll do it. 

show that someone is wrong by attacking his arguments. that's what makes him wrong after all. on the other hand, using the skilled technique of "you dumb!", "no u!", the only thing demonstrated to all readers is how immature you guys can be. also it's against Head-fi's rules and I can turn a blind eye only for so long. ultimately it's a lose lose strategy to attack people. 
if you are attacked, report the post and don't reply. I'm not the fastest modo there is(I sleep like 20hours a day 9days/weeks), but at some point I'll hopefully be there to react if I think I should. like now. just for the lolz, this time it's your ass that got reported, not bigshot. it takes 2 to tango. 
and @bigshot, same thing. discuss USB, that's the topic.


----------



## bigshot (Dec 1, 2018)

The subject of whether there are audible differences between USB cables has been asked and answered. One properly functioning USB cable should sound exactly the same as any other properly functioning USB cable. This can be verified by data rate tests and performing checksums to document errors. I was interested in the discussion of RF interference, but it appears that RF interference is caused by a design error in the DAC, not any property of the cable itself. So it appears that the discussion of RF is a cul-de-sac. I am very interested in the possibility of deliberately colored cables. I have never encountered one, and no one has ever been able to provide me with one, but I am open to the possibility that a deliberately hobbled cable exists. For a while I was led to believe that the other poster had cables that fit this description and had verified the fact through a controlled test. But it turned out that his controlled test was likely "purely theoretical" and was only mentioned as a rhetorical point to reach a conclusion about USB cable audibility, not as factual data open for review and analysis by others.

Is that better Castle? I'm trying.


----------



## Arpiben

bigshot said:


> The subject of whether there are audible differences between USB cables has been asked and answered. One properly functioning USB cable should sound exactly the same as any other properly functioning USB cable. This can be verified by data rate tests and performing checksums to document errors. I was interested in the discussion of RF interference, but it appears that RF interference is caused by a design error in the DAC, not any property of the cable itself. So it appears that the discussion of RF is a cul-de-sac. I am very interested in the possibility of deliberately colored cables. I have never encountered one, and no one has ever been able to provide me with one, but I am open to the possibility that a deliberately hobbled cable exists. For a while I was led to believe that the other poster had cables that fit this description and had verified the fact through a controlled test. But it turned out that his controlled test was likely "purely theoretical" and was only mentioned as a rhetorical point to reach a conclusion about USB cable audibility, not as factual data open for review and analysis by others.
> 
> Is that better Castle? I'm trying.



Curious USB cables https://curiouscables.com/ may be a good choice to start with.


----------



## sonitus mirus

Arpiben said:


> Curious USB cables https://curiouscables.com/ may be a good choice to start with.



Pure, unadulterated, slithering reptile lube.

https://curiouscables.com/faq

_*Run in*
Like most audio cables and components, the Curious usb will start to sound its best after 50-100 hours of use.


Run in has two parts:
1. Conditioning the cable itself on your system – with music.
2. Conditioning your ears to a new sound.


This second point is often overlooked.  Most usb cables provide a flat wall of sound, with “up front” detail.

The  Curious separates the instruments and vocalists into a three  dimensional space.  The way music was recorded.  And just like the real  thing.


The Curious isn’t adding anything.  There’s no trick.   The cable simply preserves the spatial cues within the recording.  The  depth and space may take some time to appreciate.  I call it “run in”  for your ears!_


----------



## castleofargh

bigshot said:


> The subject of whether there are audible differences between USB cables has been asked and answered. One properly functioning USB cable should sound exactly the same as any other properly functioning USB cable. This can be verified by data rate tests and performing checksums to document errors. I was interested in the discussion of RF interference, but it appears that RF interference is caused by a design error in the DAC, not any property of the cable itself. So it appears that the discussion of RF is a cul-de-sac. I am very interested in the possibility of deliberately colored cables. I have never encountered one, and no one has ever been able to provide me with one, but I am open to the possibility that a deliberately hobbled cable exists. For a while I was led to believe that the other poster had cables that fit this description and had verified the fact through a controlled test. But it turned out that his controlled test was likely "purely theoretical" and was only mentioned as a rhetorical point to reach a conclusion about USB cable audibility, not as factual data open for review and analysis by others.
> 
> Is that better Castle? I'm trying.


much better. now keep it up and you'll get a cookie. and who knows, maybe an actual conversation on this topic where we learn something(don't hold your breath though).
in terms of signal, most of the time when we consider something to be eliminated, it's actually that we have attenuated it down to some ludicrous level where it's accepted that nobody slightly sensible would care. the difference between legit issues and laughable nonsense, is a matter of magnitude. how much attenuation or rejection is achieved by the DAC? how effective is the shielding on the cable? how effective is the planet's atmosphere? how strong is the solar wind? how close are you from a detonating EMP bomb or a lightning strike? just a few examples making sense mostly because we have no concept of quantity whatsoever. ^_^
 that's why it seems like such a waste of time for everybody to discuss all this without measurements. 


and for those who believe that because they can feel a subjective improvement, it is evidence of objective improvement(lower noise, increased fidelity...), you guys might want to start by reading the definitions of objective and subjective. we're probably not getting anywhere before that much is clear for everybody.
about convincing me that someone is hearing a difference, all I need is being told that the differences remained in a blind test. I'm trusting like that. doesn't mean I will suddenly start believing all the other stuff because of it. or that a USB cable should cost more than 20 or 30$ no matter what it does. one step at a time and the correct experiment to get the correct answer. 






Arpiben said:


> Curious USB cables https://curiouscables.com/ may be a good choice to start with.


a bald blue eyed guy can't possibly be wrong.


----------



## bigshot

castleofargh said:


> about convincing me that someone is hearing a difference, all I need is being told that the differences remained in a blind test.



There are people who are so desperate to win at any cost that they identify the magic words they need to say to prove their claim, and they say it... even though it isn't true and it never happened. We're pretty good at rooting those people out here, but shaming them is a lot harder. I guess internet anonymity has insulated people from having to take responsibility for their words and actions. It's kind of sad because by propping themselves up, they tear down the truth.


----------



## WoodyLuvr

bigshot said:


> I was interested in the discussion of RF interference, but it appears that RF interference is caused by a design error in the DAC, not any property of the cable itself. So it appears that the discussion of RF is a cul-de-sac.


Thank you that was very informative; makes perfect sense.


----------



## GrussGott

castleofargh said:


> is a matter of magnitude. ...  that's why it seems like such a waste of time ... to discuss all this without measurements.



Heeeyyy ... I agreed with all of that!  Cool.

As for measurements, FWIW, I haven't read anyone summarize it better than @KeithEmo :

_Let's just say it this way.....
There is nothing that can be heard that cannot be measured; if it's real then it can be measured.

However, that's not to say that we always measure everything that's important, or that we necessarily know how to interpret all the measurements we make.

I agree with you about most Sabre DACs... to me they all, to some degree, tend to sound "bright and over-detailed - and as if they emphasize the upper midrange".
(And, no, that perceived difference in sound is not visible in their frequency response measurements.)
However, I would disagree that they deliver "immaculate measurements".

Most modern DACs, including Sabre DACs, deliver exceptionally flat frequency response, exceptionally low noise, and very low THD and IM distortion.
So, in terms of those three or four particular measurements, their response is indeed "exemplary".

However, they vary widely in terms of other performance metrics, including things like the impulse response of their oversampling and reconstruction filters.
Therefore, the reality is that Sabre DACs measure very well, and very much like other high quality DACs, on certain commonly used measurements.
They also measure very differently on other measurements.

But, since those other measurements are more difficult to perform, and their correlation with how a DAC sounds is less well understood, those differences tend to be overlooked.
I have absolutely no doubt whatsoever that, if you sum and subtract the outputs of two DACs that sound different, you will find that they ARE in fact different.
And, that being the case, obviously it is possible to measure those differences (probably in a variety of different ways).

However, that doesn't mean that I can tell you which specific measurements will show those differences the best, or enable us to interpret them in a meaningful way._​


----------



## jagwap

GrussGott said:


> Heeeyyy ... I agreed with all of that!  Cool.
> 
> As for measurements, FWIW, I haven't read anyone summarize it better than @KeithEmo :
> 
> ...



Yes. He put that well. So many here think the only audable factors are frequency response and THD & IM distortion. With the exception of class D amplifiers, most electronic audio equipment has nailed those specs down. We are now working at understanding the next level of performance.


----------



## Steve999

jagwap said:


> Yes. He put that well. So many here think the only audable factors are frequency response and THD & IM distortion. With the exception of class D amplifiers, most electronic audio equipment has nailed those specs down. We are now working at understanding the next level of performance.



THIS THREAD IS ABOUT USB CABLES. FRICKING USB CABLES. NOT DACs. NOT AMPLIFIERS.

Peace out.


----------



## JRG1990

GrussGott said:


> Heeeyyy ... I agreed with all of that!  Cool.
> 
> As for measurements, FWIW, I haven't read anyone summarize it better than @KeithEmo :
> 
> ...



Theres no chance a cable is gonna effect ringing since it has no oversampling or reconstruction filters, we are left with noise , distortion , frequency response and timing, what parameter do you think is missing where the cable would measure a audible difference?.

Obviously the person you quoted has a agenda to sell us dacs, so is never gonna to admit to dacs sounding the same and showing no audible differences in measurements as it would hurt the business of the company he works for. Even the measurement focused manufacture benchmark tried to claim 0.1db of roll off at 20khz was audible to try and sell there next model and claim that was the audible advantage it offered.


----------



## bigshot

jagwap said:


> Yes. He put that well. So many here think the only audable factors are frequency response and THD & IM distortion.



The only factors in sound reproduction are response, noise, distortion, amplitude and timing. I can't imagine a kind of degradation that wouldn't fit in one or more of these slots. However a USB cable isn't handling sound, it's handling a digital signal. It is basically just handing data across. It's very easy to find out if it isn't doing its job properly. All you have to do is apply a checksum at the end to see if data is being corrupted. If not, it is doing its job perfectly. All USB cables that are functioning to USB spec should be able to do that. If a cable sounds different, it is either defective, or the difference is non existent- created by an uncontrolled comparison.


----------



## Glmoneydawg

bigshot said:


> The only factors in sound reproduction are response, noise, distortion, amplitude and timing. I can't imagine a kind of degradation that wouldn't fit in one or more of these slots. However a USB cable isn't handling sound, it's handling a digital signal. It is basically just handing data across. It's very easy to find out if it isn't doing its job properly. All you have to do is apply a checksum at the end to see if data is being corrupted. If not, it is doing its job perfectly. All USB cables that are functioning to USB spec should be able to do that. If a cable sounds different, it is either defective, or the difference is non existent- created by an uncontrolled comparison.


Not an issue with usb,but maybe we should add resolution to your list of important factors in sound reproduction?


----------



## Triode User

bigshot said:


> The only factors in sound reproduction are response, noise, distortion, amplitude and timing. I can't imagine a kind of degradation that wouldn't fit in one or more of these slots. However a USB cable isn't handling sound, it's handling a digital signal. It is basically just handing data across. It's very easy to find out if it isn't doing its job properly. All you have to do is apply a checksum at the end to see if data is being corrupted. If not, it is doing its job perfectly. All USB cables that are functioning to USB spec should be able to do that. If a cable sounds different, it is either defective, or the difference is non existent- created by an uncontrolled comparison.



Except that if the cable is modifying any RF common mode noise in which case the cable may alter the sound of the music even though the digital stream is unaffected.


----------



## Glmoneydawg

Triode User said:


> Except that if the cable is modifying any RF common mode noise in which case the cable may alter the sound of the music even though the digital stream is unaffected.


RF is more likely to add a sound/noise rather than actually alter the sound....thats also going to be in the analog domain.


----------



## jagwap

bigshot said:


> The only factors in sound reproduction are response, noise, distortion, amplitude and timing. I can't imagine a kind of degradation that wouldn't fit in one or more of these slots. However a USB cable isn't handling sound, it's handling a digital signal. It is basically just handing data across. It's very easy to find out if it isn't doing its job properly. All you have to do is apply a checksum at the end to see if data is being corrupted. If not, it is doing its job perfectly. All USB cables that are functioning to USB spec should be able to do that. If a cable sounds different, it is either defective, or the difference is non existent- created by an uncontrolled comparison.



We've had this discussion before, so I don't see any point in having it again for the benefit of this audience as the outcome will be the same: you will never take on any new ideas. There are other measurements everone else accepts, like crosstalk, CMRR, phase and many more. 

This thread is about USB cables, and while I will take on new ideas about what effect they may have, I generally agree that they are very unkilely to have an effect on the audio, except for RF system wide performance. I say this as an audio equipment designer, and have spent considerable time in EMC labs measuring and modifying products to pass CE and FCC. There is a pass/fail for these standards. However RF immunity and conduction is a variable. Just because you pass a government standard, who don't care about audio, only stopping interference with ambulance radios etc, it doesn't mean you can't go further to get better audio immunity. Also audio isn't only sensitive to the frequencies that the government regulations care about.

Audio equipment can demodulate RF into the audio band. Try putting you mobile near some audio gear while calling it. In the US Sprint and Verizon are best for the demonstration as they are CDMA. Not all will make a noise, but some will. It doesn't prove much as it is only around the 1-2 Ghz. But it shows demodulation at a frequency governments don't legislate immunity.


----------



## Brooko

jagwap said:


> We've had this discussion before, so I don't see any point in having it again for the benefit of this audience as the outcome will be the same: you will never take on any new ideas. There are other measurements everone else accepts, like crosstalk, CMRR, phase and many more.
> 
> This thread is about USB cables, and while I will take on new ideas about what effect they may have, I generally agree that they are very unkilely to have an effect on the audio, except for RF system wide performance. I say this as an audio equipment designer, and have spent considerable time in EMC labs measuring and modifying products to pass CE and FCC. There is a pass/fail for these standards. However RF immunity and conduction is a variable. Just because you pass a government standard, who don't care about audio, only stopping interference with ambulance radios etc, it doesn't mean you can't go further to get better audio immunity. Also audio isn't only sensitive to the frequencies that the government regulations care about.
> 
> Audio equipment can demodulate RF into the audio band. Try putting you mobile near some audio gear while calling it. In the US Sprint and Verizon are best for the demonstration as they are CDMA. Not all will make a noise, but some will. It doesn't prove much as it is only around the 1-2 Ghz. But it shows demodulation at a frequency governments don't legislate immunity.



Yes - but how does that relate to:
 - cables
 - the claims that a USB cable can improve sound in such areas as frequency response, sound stage perception, transients etc ad nauseum

I agree wholeheartedly that RF noise has the potential to be passed into the analog domain (post the DAC), but does this relate to USB cables (which was the original point of the thread)?


----------



## bigshot (Dec 2, 2018)

Glmoneydawg said:


> Not an issue with usb,but maybe we should add resolution to your list of important factors in sound reproduction?



Resolution is the same as distortion. In the broadest sense of the word, distortion is anything that causes alteration of the sound. So muddling it up would count. Distortion is a very broad category. There's more kinds of distortion than just the couple of ratings you find on spec sheets.



Triode User said:


> Except that if the cable is modifying any RF common mode noise in which case the cable may alter the sound of the music even though the digital stream is unaffected.



Didn't you already say that interference was a problem with DACs not being protected from RF, not a fault in the cable itself? I'd still like to know a specific make and model of a DAC that is subject to this problem if you happen to know one.



jagwap said:


> We've had this discussion before, so I don't see any point in having it again for the benefit of this audience as the outcome will be the same: you will never take on any new ideas. There are other measurements everone else accepts, like crosstalk, CMRR, phase and many more.



If we had this discussion before, I probably agreed that those could be problems, but they would fall under the umbrella of one the other ones I already mentioned.


----------



## god-bluff (Dec 2, 2018)

I find Amazon Basics USB cables to be very good. Nicely made cheap as chips and do the job.


----------



## bigshot

I like them a lot too. I used to by Radio Shack and Monoprice, but now with Prime it's easier to just order Amazon Basics.


----------



## god-bluff

Curious Cables (Curious by name.. .) have released  a USB cable specifically for Chord  products, the 'Hugo Link' at just $170.  

How can a USB cable possibly be specific to a particular brand? How can a digital cable be 'tuned for particular devices?!? How can a cable be worth around 40 % of a Chord Mojo. Its certainly beyond me!

 I think I remember Rob Watts saying that USB cables make no difference. Certainly the cable they supply are just basic ones. 

I'd rather trust Chord than any cable manufacturer


----------



## bigshot (Dec 2, 2018)

In text that probably doesn't play the way you were hearing it in your head.


----------



## jagwap

Brooko said:


> Yes - but how does that relate to:
> - cables
> - the claims that a USB cable can improve sound in such areas as frequency response, sound stage perception, transients etc ad nauseum
> 
> I agree wholeheartedly that RF noise has the potential to be passed into the analog domain (post the DAC), but does this relate to USB cables (which was the original point of the thread)?



Of course. RF passed from the PC to the DAC will get in to the DAC circuitry including the switched capacitor and analogue sections. How much this is attenuated is what counts. If it is not attenuated enough, then the geometry of the cable can vary the amplitude and frequency of the RF that gets in. Also the RF noise from the PC will vary in amplitude and frequency from case to case. So there is not pass/fail, but system wide attenuation of the RF spectrum. This will not affect measured frequency response, but if bad enough it could affect other measurements and audable factors. Also the RF may pass through the DAC and reach the power amps with similar possible effects.

So it is a system wide issue. It should be inaudible, but it is ill advised to say it is impossible to have an effect unless you are in a position of knowledge such as an experienced designer, like Robert Watts.


----------



## WoodyLuvr (Dec 2, 2018)

god-bluff said:


> Curious Cables (Curious by name.. .) have released  a USB cable specifically for Chord  products, the 'Hugo Link' at just $170.
> 
> How can a USB cable possibly be specific to a particular brand? How can a digital cable be 'tuned for particular devices?!? How can a cable be worth around 40 % of a Chord Mojo. Its certainly beyond me!
> 
> ...


Only Curious George would know... as he is the one delivering the bananas to Hugo.


----------



## Triode User

god-bluff said:


> Curious Cables (Curious by name.. .) have released  a USB cable specifically for Chord  products, the 'Hugo Link' at just $170.
> 
> How can a USB cable possibly be specific to a particular brand? How can a digital cable be 'tuned for particular devices?!? How can a cable be worth around 40 % of a Chord Mojo. Its certainly beyond me!
> 
> ...



The Chord Company who make cables and Chord Electronics who make DACs, amps etc are two completely different and unrelated companies.


----------



## bigshot

jagwap said:


> So it is a system wide issue. It should be inaudible, but it is ill advised to say it is impossible to have an effect unless you are in a position of knowledge such as an experienced designer, like Robert Watts.



Honestly, I can't figure out what you say. I've never had this problem myself and if only one DAC designer had the solution to it, then everyone with any other DAC would be reporting this as a problem. Is this a common complaint? Or is this another example of a solution creating its own need again?


----------



## Triode User

bigshot said:


> Honestly, I can't figure out what you say. I've never had this problem myself and if only one DAC designer had the solution to it, then everyone with any other DAC would be reporting this as a problem. Is this a common complaint? Or is this another example of a solution creating its own need again?



Get out and talk to more DAC and server/streamer designers and you will find that it is an issue which is very much the focus of their attention at the moment.


----------



## god-bluff

Triode User said:


> The Chord Company who make cables and Chord Electronics who make DACs, amps etc are two completely different and unrelated companies.


I am totally aware of that. I wasn't taking about The Chord (cable) Company !!!!


----------



## bfreedma

Triode User said:


> Get out and talk to more DAC and server/streamer designers and you will find that it is an issue which is very much the focus of their attention at the moment.




I'd be more interested in seeing something from a party who doesn't have a financial interest in finding and solving that "problem".

If there is any hard evidence of this being an issue and cables audibly attenuating it, can you post it?


----------



## WoodyLuvr

jagwap said:


> Of course. RF passed from the PC to the DAC will get in to the DAC circuitry including the switched capacitor and analogue sections. How much this is attenuated is what counts. If it is not attenuated enough, then the geometry of the cable can vary the amplitude and frequency of the RF that gets in. Also the RF noise from the PC will vary in amplitude and frequency from case to case. So there is not pass/fail, but system wide attenuation of the RF spectrum. This will not affect measured frequency response, but if bad enough it could affect other measurements and audable factors. Also the RF may pass through the DAC and reach the power amps with similar possible effects.
> 
> So it is a system wide issue. It should be inaudible, but it is ill advised to say it is impossible to have an effect unless you are in a position of knowledge such as an experienced designer, like Robert Watts.


Has this RF event, passing from PC to DAC via USB cable, ever been proven and/or documented? And more specifically referring to certain cable geometries acting as a conduit for such RF? I always believed that one would assume it would be inadequately/improperly applied EMI shielding of the devices rather than any sort of digital cabling.


----------



## bigshot (Dec 3, 2018)

bfreedma said:


> If there is any hard evidence of this being an issue and cables audibly attenuating it, can you post it?



Earlier he said that a different cable couldn't fix the problem. The only way to correct it was in the design of the DAC. I would like a specific example of a DAC that is prone to this problem and where it has been widely reported. I sure have never run across anything like this.

If this is only discussed in terms of one particular brand that solves the "problem", then like you say, it smells like sales pitch. Similar to the way "jitter" was such a bugaboo and all the DAC manufacturers were touting it... until people realized that it wasn't present at levels that were anywhere near audible. I have a feeling this is like that. It's a theoretical/non-existent problem with a very expensive solution that is conveniently offered by snake oil salesmen.

If it's real, someone must have measured it. A simple null test between DACs with and without the problem would reveal if it's an issue or not. Are there any measurements on this Triode?


----------



## bfreedma

bigshot said:


> Earlier he said that a different cable couldn't fix the problem. The only way to correct it was in the design of the DAC. I would like a specific example of a DAC that is prone to this problem and where it has been widely reported. I sure have never run across anything like this.
> 
> If this is only discussed in terms of one particular brand that solves the "problem", then like you say, it smells like sales pitch. Similar to the way "jitter" was such a bugaboo and all the DAC manufacturers were touting it... until people realized that it wasn't present at levels that were anywhere near audible. I have a feeling this is like that. It's a theoretical/non-existent problem with a very expensive solution that is conveniently offered by snake oil salesmen.
> 
> If it's real, someone must have measured it. A simple null test between DACs with and without the problem would reveal if it's an issue or not. Are there any measurements on this Triode?




While it isn't a perfect example as USB cables used to connect a computer to a data storage or output device utilize a checksum to ensure integrity, back when I used to design data centers and execute data center moves for highly regulated industries, there were no regulations around USB cables and their susceptibility to various forms of interference.  

Given the concept that interference could also cause data transmission failure due to dropouts, the amount of interference necessary to cause/avoid them was a not part of regulations I had to follow and I never experienced it in production.


----------



## Triode User

bfreedma said:


> While it isn't a perfect example as USB cables used to connect a computer to a data storage or output device utilize a checksum to ensure integrity, back when I used to design data centers and execute data center moves for highly regulated industries, there were no regulations around USB cables and their susceptibility to various forms of interference.
> 
> Given the concept that interference could also cause data transmission failure due to dropouts, the amount of interference necessary to cause/avoid them was a not part of regulations I had to follow and I never experienced it in production.



I don’t think drop outs is the issue. In fact I have never had a drop out in many years of audio streaming by usb. My point is the RF noise overlay on top of the digital signal and how usb cables either by accident or design might change that RF noise and so give rise to the thought that usb cables can change the music we heat from a dac.


----------



## bigshot (Dec 3, 2018)

Yes, It would be raising the noise floor. It would be perfectly measurable. I'm sure all DACs are measured when they prepare the specs for dynamic range. Would RF noise not factor into those measurements? Because the specs of DACs seem to always indicate noise floors that are far far below the threshold of audibility. If this noise is going to be audible, it is going to be measurable. Has this been measured and exactly what impact does it have on the dynamic range? Or are we talking about RF noise that falls below the threshold of audibility.

I think I asked you before if RF could create noise above an attenuation level of -50dB. Do you know if this is the case?


----------



## Triode User

bigshot said:


> Yes, It would be raising the noise floor. It would be perfectly measurable. I'm sure all DACs are measured when they prepare the specs for dynamic range. Would RF noise not factor into those measurements? Because the specs of DACs seem to always indicate noise floors that are far far below the threshold of audibility. If this noise is going to be audible, it is going to be measurable. Has this been measured and exactly what impact does it have on the dynamic range? Or are we talking about RF noise that falls below the threshold of audibility.
> 
> I think I asked you before if RF could create noise above an attenuation level of -50dB. Do you know if this is the case?



As per this 


jagwap said:


> Audio equipment can demodulate RF into the audio band.



It is not a matter of the direct noise being heard. In my experience it manifests as a noticeable harshening to the upper register. The easiest way to know it is there is to reduce it by ferrites and then to hear the clear and repeatable difference in sound.


----------



## bfreedma

Triode User said:


> As per this
> 
> 
> It is not a matter of the direct noise being heard. In my experience it manifests as a noticeable harshening to the upper register. The easiest way to know it is there is to reduce it by ferrites and then to hear the clear and repeatable difference in sound.




Great - all we need is a few blind tests and measurements and that could be easily confirmed.  Are you willing to perform them?


----------



## Triode User

bfreedma said:


> Great - all we need is a few blind tests and measurements and that could be easily confirmed.  Are you willing to perform them?



I do blind tests most weeks with customers and BNC digital cables where I have the cables in place and then change them unsighted with the listener and so far they have got 100% identification of my cables. I am sure of my ground with BNC digital cables but I admit I am not sure with USB because I have not tried it. I admit therefore that what I am saying about USB is conjecture but it is based on solid evidence with the BNC digital cables.

Probably what I need to do is make some USB cables using similar principles to the BNC cables, try them and then come back. I am happy to do that.


----------



## bigshot

Triode User said:


> It is not a matter of the direct noise being heard. In my experience it manifests as a noticeable harshening to the upper register.



So it is distortion that follows the signal, not noise... Are you sure about that? If so, it's easily detected in a null test. Can you tell me a DAC that is particularly subject to this kind of distortion so I can check it out? It probably would show up in the THD ratings, wouldn't it?

If you only answer one of my questions, please make it the one about the DAC that is particularly subject to RF.


----------



## castleofargh

I remember measuring small improvements on my old ODAC when using the USB cable provided with a ferrite bead compared to some other random one. I believe JDS documented that at some point. but I can't say that I could hear a difference. also if a ferrite bead is the answer, why wouldn't the DAC manufacturer provide it or even better, have it inside the DAC? I agree with the possibility, but I'm talking about a small DAC that costs the price of some of the USB cables discussed in this topic. if I purchase an expensive DAC and the guy didn't implement some ferrite bead that could instantly improve the overall fidelity, it's probably time to go get a DAC from a better designer. 


 also in my limited experience, op amps and amplifiers in general tend to be the bigger issue with RFI and other unwanted signals(am I wrong about that idea?). I'd be slightly surprised to have significant issues in the DAC to the point where the total volume of a shielded cable would grab signals that make a noticeable difference compared to another random shielded cable, while at the same time having a problem free amplifier. I'm sure it happens, but it's certainly not what I'm used to.


----------



## Double C

Triode User said:


> I do blind tests most weeks with customers and BNC digital cables where I have the cables in place and then change them unsighted with the listener and so far they have got 100% identification of my cables.



What are customers saying/hearing is different about your cables then the others?


----------



## Triode User

Double C said:


> What are customers saying/hearing is different about your cables then the others?



They don’t sound as harsh.


----------



## Triode User

bigshot said:


> So it is distortion that follows the signal, not noise... Are you sure about that? If so, it's easily detected in a null test. Can you tell me a DAC that is particularly subject to this kind of distortion so I can check it out? It probably would show up in the THD ratings, wouldn't it?
> 
> If you only answer one of my questions, please make it the one about the DAC that is particularly subject to RF.



A for instance, the last cable I sold was to a customer with a TAC DAC8. (I think I got that name right). I am not sure it is particularly susceptible to RF noise.


----------



## bigshot

I'd like to know a model where this problem has been identified and reported. If you don't know of any, that's OK.


----------



## Steve999

castleofargh said:


> I remember measuring small improvements on my old ODAC when using the USB cable provided with a ferrite bead compared to some other random one. I believe JDS documented that at some point. but I can't say that I could hear a difference. also if a ferrite bead is the answer, why wouldn't the DAC manufacturer provide it or even better, have it inside the DAC? I agree with the possibility, but I'm talking about a small DAC that costs the price of some of the USB cables discussed in this topic. if I purchase an expensive DAC and the guy didn't implement some ferrite bead that could instantly improve the overall fidelity, it's probably time to go get a DAC from a better designer.
> 
> 
> also in my limited experience, op amps and amplifiers in general tend to be the bigger issue with RFI and other unwanted signals(am I wrong about that idea?). I'd be slightly surprised to have significant issues in the DAC to the point where the total volume of a shielded cable would grab signals that make a noticeable difference compared to another random shielded cable, while at the same time having a problem free amplifier. I'm sure it happens, but it's certainly not what I'm used to.



I've got some kind of silver junky USB cable with a ferrite band I'm using right now (don't know what it came with) and Sony provides USB cables with ferrite bands once in a while based on my distant memory. I always wondered about them.


----------



## GrussGott (Dec 3, 2018)

JRG1990 said:


> *You've just dismissed all the objective data *supporting theirs no audible difference between usb cables, but *haven't provided any that supports your argument that there is*.



Well sure, but in my defense that's only because that's not my argument.

Rather: "it's possible, I've heard a difference, many others have, thus observed phenomena deserves investigation until the mechanism is known and manipulable, or proven false."  However, many do the unscientific thing and just jump to, "welp, no makes the most sense to me (because assumptions/speculation), so I'll just assume and advise that's scientific fact without the actual data proof it really is".  And then for some weird reason (big ego, lack of humility, inferiority complex), they're so bold in their unproven opinion, they start asking others to disprove their unproven opinion!  Bizarre right??

So my argument: if one is doling out advice, be able to prove it as fact or disclose you don't know for certain (and ideally advise the safe middle ground)  I probably got that way because in all the sciency work I've done for my career, advice based on unproven assumptions kills people.  (as far as I can tell, people in audio industry have a lower standard of knowledge for giving advice)

As they say in aviation: there are old pilots and there are bold pilots, but there are no old bold pilots.*

* Interesting Counterpoint: As they say in investment banking: boldness is genius.

So ... one can decide if science is more like aviation or investment banking.


----------



## Triode User

bigshot said:


> I'd like to know a model where this problem has been identified and reported. If you don't know of any, that's OK.



So far all customers irrespective of dac report a decrease in harshness. That implies widespread RF susceptibility but to be accurate I do not know of models where the problem has been identified and reported.


----------



## gregorio

Triode User said:


> My point is the RF noise overlay on top of the digital signal and how usb cables either by accident or design might change that RF noise and so give rise to the thought that usb cables can change the music we heat from a dac.



Yes but my point is, RF is not going to affect the digital signal itself and change the 0's or 1's. The only possibility is therefore RF leaking into the analogue section which indicates a poorly designed DAC, as even cheap DACs are able to isolate well enough to reduce interference to many times below audibility, so why apparently can't audiophile DACs? If you do have a faulty DAC, why wouldn't you want to fix/replace that DAC instead of buying a cable that costs more than a new non-faulty DAC? It's this logic I don't get, even if audiophile USB cables could fix some DAC leakage issue and I've not seen any evidence to suggest they can.

Furthermore, I've done a fair bit of testing in the past on S/PDiff (using BNC coax), although only once on a consumer DAC (actually it was an AVR), I've not measured any interference even near audibility and that was in a high RF environment.

G


----------



## bigshot (Dec 4, 2018)

Triode User said:


> So far all customers irrespective of dac report a decrease in harshness. That implies widespread RF susceptibility but to be accurate I do not know of models where the problem has been identified and reported.



Audiophiles claim everything they buy makes a "night and day" difference. If we accepted anecdotal testimonials on manufacturer's website, then Brilliant Pebbles makes a huge impact on soundstage and clarity.

If it's audible, it's measurable. Measuring isn't hard. If it's real, someone will have measured it. If dealers have to depend on anecdotal testimonials, it probably isn't real. If it is just a new problem and no one has measured it yet, you can help me get access to a unit that is clearly susceptible to this problem and we can set up a controlled listening test and measurements of it, I'm sure the folks around here would be happy to pitch in and help you do that. But just saying "all DACs have this problem" isn't good enough, because a lot of us have DACs that are audibly transparent and clearly don't have high levels of RF noise.

I would like to get access to any DAC that isn't audibly transparent for any reason. I've been asking that for over a year, and no one yet has been able to help with that. That tells me something.


----------



## Triode User

bigshot said:


> a lot of us have DACs that are audibly transparent and clearly don't have high levels of RF noise



How do you know that?


----------



## GrussGott (Dec 4, 2018)

JRG1990 said:


> what parameter do you think is missing where the cable would measure a audible difference?.  ...  Obviously the person you quoted has a agenda to sell us dacs



(1.) Assuming your parameter question is even the right question (and that'd be an assumption, not science), it doesn't matter what you or I "think is missing" because we're not digital signals processing scientists, thus any conclusion we'd come to would be likely wrong or at least incomplete.

(2.) I have no idea what his "agenda" is or isn't, and - again - you're making a large assumption there.  You might want to remember that doctors, lawyers, accountants, pilots, and many other professions all have "agendas" to give you bad advice.  For example, a doctor gets paid when you're sick, a lawyer get paid when you need one, same with an accountant, a pilot gets paid as long as he's sitting in the cockpit so what does he care about delays?

I guess I'm wondering how you get through life never using doctors, accountants, lawyers, or anyone else that gets paid to solve a problem for you.  (the person who represents themselves has a fool for a client and all that)

Anyway, I judge advice on its merits, and his advice was well written and matches that of many others I've heard from - if you choose to ignore it, I'm not surprised - I trust your advice way less since you don't make DACs or cables or anything.  (nor does it match what digital signals processing engineers have shown me)


----------



## bigshot

Triode User said:


> How do you know that?



Specs, measurements, controlled listening tests. I have an Oppo HA-1. It is audibly transparent by all three of those. I've never seen any measurement of a DAC that had audible levels of noise or distortion, have you?


----------



## jagwap (Dec 4, 2018)

bigshot said:


> Specs, measurements, controlled listening tests. I have an Oppo HA-1. It is audibly transparent by all three of those. I've never seen any measurement of a DAC that had audible levels of noise or distortion, have you?



I have. I can say that only if I use your own description of what distortion covers: everything that is different to the original signal. If it is THD and IMD then no. It had audable levels of phase error. I also heard an amplifier that had audable levels of crosstalk. Neither of these are usually described as distortion, as they generally have specific decriptions in audio design. However you have used the definition of dustortion broadly here before, so I am assuming that is how you continue to use it.


----------



## bigshot (Dec 4, 2018)

Has it been measured to have differences, or has there been a blind controlled test that verifies that it's audible? If so, what make and model? I'm looking to find out if a colored DAC actually exists. All I've found so far is reports that are anecdotal and sighted with no real controls.

Do you have access to this DAC so we can set up a test and measurements as a group?


----------



## jagwap

bigshot said:


> Has it been measured to have differences, or has there been a blind controlled test that verifies that it's audible? If so, what make and model? I'm looking to find out if a colored DAC actually exists. All I've found so far is reports that are anecdotal and sighted with no real controls.
> 
> Do you have access to this DAC so we can set up a test and measurements as a group?



It was fixed. I try not to released know issues.


----------



## bigshot

Ah. It was a defective one. That happens.


----------



## JRG1990

So the only time a a usb cable makes a difference Is when the dac  defective spending silly money on a cable to fix the problem is madness replacing the defective dac seems like the most logical solution , measurements show even the cheapest cables work fine and are the best performance your gonna get with a properly functioning dac.


----------



## bigshot

That's my takeaway from this thread too.


----------



## JRG1990

At least after 99 pages we have all finally reached an agreement.


----------



## jagwap

JRG1990 said:


> At least after 99 pages we have all finally reached an agreement.



My understanding is "all" is not in general a subset of the total. The lesson I take away from this discussion is it is valuable to learn that the people that agree with you are not always the people you can learn from.

I do not use fancy USB cables. But that is my choice. I have proposed why they "may" make a difference. RF susceptablility isn't a yes/no situation. There is a legislation pass/fail in some countries, but sound quality often requires a higher standard, and some designers have higher requirements than others.


----------



## jagwap

bigshot said:


> Ah. It was a defective one. That happens.



No it wasn't defective in terms generally accepted as measuring well. I have some measurement requirements that I have found make a difference listening blind that I want a product to pass. So I "fixed" it to my standard. There are plenty of DACs out there that wouldn't pass my tests. I am being deliberately cryptic as this is some proprietary knowledge I have picked up in my travels. Don't worry, I think the man involved in your Oppo DAC knows this too.


----------



## Arpiben

jagwap said:


> No it wasn't defective in terms generally accepted as measuring well. I have some measurement requirements that I have found make a difference listening blind that I want a product to pass. So I "fixed" it to my standard. There are plenty of DACs out there that wouldn't pass my tests. I am being deliberately cryptic as this is some proprietary knowledge I have picked up in my travels. Don't worry, I think the man involved in your Oppo DAC knows this too.



Do you mind sharing the DAC Output effects of an item not coping with your standards? Just the output, no item name or any EMC levels. Thanks.


----------



## bigshot (Dec 6, 2018)

jagwap said:


> I do not use fancy USB cables. But that is my choice. I have proposed why they "may" make a difference. RF susceptablility isn't a yes/no situation. There is a legislation pass/fail in some countries, but sound quality often requires a higher standard, and some designers have higher requirements than others.



So in other words, you're saying you don't know anything about it, you just made a choice to not use fancy cables because you didn't want to spend money on that. That is fine. But saying that in an internet forum doesn't really help anyone else make a decision... especially if they can afford fancy cables and want to know if that would be money well spent. They are looking for an indication one way or the other, not a personal decision based on not knowing much about it.

By the way, passing audio across is one of the easiest things that USB cables do. Digital audio is a fraction of the size and speed required of most things USB cables pass... files from hard drive to hard drive, HD video, etc. And audio is only required to keep a buffer full on the DAC side. That is even easier than real time streaming.

I'll wait until you are prepared to speak about your standards. Until then, I'll stick to the ones that make all of my digital audio devices audibly transparent to me.


----------



## GrussGott

bigshot said:


> So in other words, you're saying you don't know anything about it, you just made a choice to not use fancy cables because you didn't want to spend money on that. That is fine. But saying that in an internet forum doesn't really help anyone else make a decision... especially if they can afford fancy cables and want to know if that would be money well spent. They are looking for an indication one way or the other, not a personal decision based on not knowing much about it.
> 
> By the way, passing audio across is one of the easiest things that USB cables do. Digital audio is a fraction of the size and speed required of most things USB cables pass... files from hard drive to hard drive, HD video, etc. And audio is only required to keep a buffer full on the DAC side. That is even easier than real time streaming.
> 
> I'll wait until you are prepared to speak about your standards. Until then, I'll stick to the ones that make all of my digital audio devices audibly transparent to me.



HOLY CRAP!  I ... I ... I ... agree ... with aaallll of this.


----------



## jagwap

bigshot said:


> So in other words, you're saying you don't know anything about it...   a personal decision based on not knowing much about it.


 
I have said I do not use fancy USB cables.because I do not think they are necessary. *I am agreeing with you!*

That is either a troll comment or an insult to my abilities as a professional designer of audio equipment. I have explained myself, and now you are trying to provoke. Do you have some kind of internet forum tourettes?


----------



## jagwap

Arpiben said:


> Do you mind sharing the DAC Output effects of an item not coping with your standards? Just the output, no item name or any EMC levels. Thanks.



I wasn't refering to RF, but another aspect outside of "conventional" measurements.

I won't name other brands as deficient, as that would be unprofessional.


----------



## Whazzzup

I use fancy cables because I don’t function properly.


----------



## bigshot

jagwap said:


> I won't name other brands as deficient, as that would be unprofessional.



Are you a member of the trade? I'm always looking for a DAC or player that isn't audibly transparent. If you know of one, it wouldn't be unprofessional to mention it. In fact, it would be helpful!


----------



## Redcarmoose

bigshot said:


> Are you a member of the trade? I'm always looking for a DAC or player that isn't audibly transparent. If you know of one, it wouldn't be unprofessional to mention it. In fact, it would be helpful!



You just asked a fellow member if he used different DACs which could have “colored” his subjective listening tests rotating in different USB cables. So which is it? All DACs the same or different? Get your own personal facts straight.


----------



## bigshot (Dec 6, 2018)

Redcarmoose said:


> You just asked a fellow member if he used different DACs which could have “colored” his subjective listening tests rotating in different USB cables. So which is it? All DACs the same or different? Get your own personal facts straight.



Happy to clear that up for you! Every DAC, DAP, amp and digital audio disc player that I've ever gotten has been audibly transparent, They all sound exactly the same- perfect. I'm looking for one that *isn't* audibly transparent- or in other words, colored. If anyone has one that doesn't sound just like every other, and they've gone to the trouble to carefully make sure of that for themselves, let me know. I'd like to borrow it to do some tests. No one has been able to provide me with one yet.



jagwap said:


> I have said I do not use fancy USB cables.because I do not think they are necessary. *I am agreeing with you!*



Sorry, I was reading your comment as meaning that USB cables may make a difference if someone has a higher standard, but you don't need that high of a standard yourself. The highest standard necessary for the purposes of listening to music in the home is audible transparency. In my book, the quest stops there. A professional sound engineer in a studio might need more, but regular people don't. To be honest, I doubt that a professional sound engineer would even need fancy USB cables. They wouldn't have RF problems like that.


----------



## Redcarmoose

bigshot said:


> Happy to clear that up for you! Every DAC, DAP, amp and digital audio disc player that I've ever gotten has been audibly transparent, They all sound exactly the same- perfect._* I'm looking for one that *isn't* audibly transparent- or in other words, colored.*_ If anyone has one that doesn't sound just like every other, and they've gone to the trouble to carefully make sure of that for themselves, let me know. I'd like to borrow it to do some tests._* No one has been able to provide me with one yet.*_
> 
> 
> 
> Sorry, I was reading your comment as meaning that USB cables may make a difference if someone has a higher standard, but you don't need that high of a standard yourself. The highest standard necessary for the purposes of listening to music in the home is audible transparency. In my book, the quest stops there. A professional sound engineer in a studio might need more, but regular people don't. To be honest, I doubt that a professional sound engineer would even need fancy USB cables. They wouldn't have RF problems like that.



My IPods are on the flat side. The Cambridge Audio DACMagic Plus is cold, and my favorite Sony TA amp/DAC is warm. But..........I'm not sending em out anywhere. I'm sure they would graph out the same as they sound. Only seen graphs on the IPods. Also due to the construction the Sony 1Z and 1A sound very different, mainly due to the amplification probably? 1000s of posts about the difference.


----------



## Brooko

bigshot said:


> Happy to clear that up for you! Every DAC, DAP, amp and digital audio disc player that I've ever gotten has been audibly transparent, They all sound exactly the same- perfect. I'm looking for one that *isn't* audibly transparent- or in other words, colored. If anyone has one that doesn't sound just like every other, and they've gone to the trouble to carefully make sure of that for themselves, let me know. I'd like to borrow it to do some tests. No one has been able to provide me with one yet.



Bigshot - there are plenty of examples of dac/amps sounding different.  In the iPod world, the 5 series (Wolfson) was audibly on the warm side vs the Cirrus Logic being cooler / more neutral.  I have an E17K which is the most clinically neutral device I own (ruler flat).  I have an Audio-gd NFB12 which is tonally very warm.

I’m not sure if it’s Dac filters, or amps, or 2nd harmonic distortion - but the differences exist.  For some the aim may be high transparency. For others it may be tonally pleasant. You know me - I’m a complete sceptic at heart. But I’d be first to advise that in blind volume matched tests - some dac/amp combos are audibly different.  Are they all transparent -  no.  Some are coloured and intentionally so.


----------



## bigshot (Dec 6, 2018)

Redcarmoose said:


> My IPods are on the flat side. The Cambridge Audio DACMagic Plus is cold, and my favorite Sony TA amp/DAC is warm. But..........I'm not sending em out anywhere. I'm sure they would graph out the same as they sound. Only seen graphs on the IPods. Also due to the construction the Sony 1Z and 1A sound very different, mainly due to the amplification probably? 1000s of posts about the difference.



Have you done level matching, direct A/B switching and blind comparison? As you say, there are thousands of anecdotal reports of differences, but I'm looking for someone who has made an effort to make sure they are reporting accurately. I could chase every crackpot claim on Head-Fi, but that would be a waste of time. I've done controlled listening tests on my own equipment and it all sounds exactly the same- audibly transparent. I don't think coloration is nearly as common as some people think it is. In fact, I bet if you did a controlled test on your DACs, you'd find they sound the same too.



Brooko said:


> Bigshot - there are plenty of examples of dac/amps sounding different.  In the iPod world, the 5 series (Wolfson) was audibly on the warm side vs the Cirrus Logic being cooler / more neutral.  I have an E17K which is the most clinically neutral device I own (ruler flat).  I have an Audio-gd NFB12 which is tonally very warm.



Are you comparing from the line out, not the headphone out? Because I know that there are differences in impedance, but that just depends on which headphone you are using. I'm looking for electronics that are colored. You're interesting me though. Have you done a controlled listening test with the NFB12 through line out? I have an older iPod with a Wolfson DAC and I think some of my other Apple stuff has Cirrus Logic and they are all completely transparent through line out. I haven't found a DAC chip that sounds different yet. (Sabre Reference and whatever is in a $40 Walmart DVD player are transparent too.) I think a lot of the reports about DACs sounding different are actually due to impedance differences.

I would really like to assemble a list of equipment that is deliberately colored. I just can't find any myself. It would be nice to measure them and define exactly what the coloration is too.


----------



## Glmoneydawg (Dec 6, 2018)

bigshot said:


> Have you done level matching, direct A/B switching and blind comparison? As you say, there are thousands of anecdotal reports of differences, but I'm looking for someone who has made an effort to make sure they are reporting accurately. I could chase every crackpot claim on Head-Fi, but that would be a waste of time. I've done controlled listening tests on my own equipment and it all sounds exactly the same- audibly transparent. I don't think coloration is nearly as common as some people think it is. In fact, I bet if you did a controlled test on your DACs, you'd find they sound the same too.
> 
> 
> 
> ...


I have to agree with you....i can't imagine how the digital domain can be responsible for adjectives like warmer,cooler ect(short of using equalization) bits is bits,i have in the distant past had digital products that sounded a little dissimilar but put it down the analog output(vacuum tube output sections,beach portable electronics ect...analog!


----------



## Redcarmoose (Dec 6, 2018)

Glmoneydawg said:


> I have to agree with you....i can't imagine how the digital domain can be responsible for adjectives like warmer,cooler ect(short of using equalization) bits is bits,i have in the distant past had digital products that sounded a little dissimilar but put it down the analog output(vacuum tube output sections,beach portable electronics ect...analog!



The biggest differences I would guess are noticed due to the amp sections. Folks changing out operational amplifier chips, or even exotic amplifier topography like Sony Corporations DSEE HX has an unremovable effect on the sound.

Of course if you believe all amplifiers sound exactly the same, we have no argument to continue here.


----------



## Glmoneydawg (Dec 6, 2018)

Redcarmoose said:


> The biggest differences I would guess are noticed due to the amp sections. Folks changing out operational amplifier chips, or even exotic amplifier topography like Sony Corporations DSEE HX has an unremovable effect on the sound.
> 
> Of course if you believe all amplifiers sound exactly the same, we have no argument to continue here.


Without some form of argument this thread is dead....don't think i could bear it lol...having said that i have owned some pretty exotic amp/ speaker combos over the years...the power amp specs where pretty much identical ....didn't sound the same though(not hugely different )...was happy with all of them.


----------



## bigshot (Dec 6, 2018)

As long as you use a modern solid state amplifier with the speakers or headphones that were are designed to be used with, it should be audibly transparent. I have only had four or five amps over the years, but they all are the same. Of course there are colored tube amps, but you know going in that the whole point of a tube amp is coloration.


----------



## Glmoneydawg (Dec 6, 2018)

bigshot said:


> As long as you use a modern solid state amplifier with the speakers or headphones that were are designed to be used with, it should be audibly transparent. I have only had four or five amps over the years, but they all are the same. Of course there are colored tube amps, but you know going in that the whole point of a tube amp is coloration.


I'm betting all 5 of your amps where solid state....kinda takes you out of this argument my friend .....ever owned a modern tube amp?I know you have said your brother has owned the same tube amp for about 40 years so....


----------



## Glmoneydawg

Don't get me wrong...electrostatic speakers and low impedance speakers in general can roll off the extreme high end a little on a low power tube amp.....but at our age whats the big deal?


----------



## jagwap

Glmoneydawg said:


> Don't get me wrong...electrostatic speakers and low impedance speakers in general can roll off the extreme high end a little on a low power tube amp.....but at our age whats the big deal?



Also on almost all class D amps. That big output inductor is not ideal. It also adds a few dB or so on linductive tweeters. Most solid state amplifier channels are class d as of over 15 years ago. This is one reason Hypex classD has done so well. It doesn't suffer from this.

I love a good valve amp. The trouble is most of them are far from good.

The deal is phase shift.


----------



## Glmoneydawg

jagwap said:


> Also on almost all class D amps. That big output inductor is not ideal. It also adds a few dB or so on linductive tweeters. Most solid state amplifier channels are class d as of over 15 years ago. This is one reason Hypex classD has done so well. It doesn't suffer from this.
> 
> I love a good valve amp. The trouble is most of them are far from good.
> 
> The deal is phase shift.


Yep....but thankfully there are good ones


----------



## GrussGott (Dec 7, 2018)

Brooko said:


> Bigshot - there are plenty of examples of dac/amps sounding different.



These 99 pages are all starting to make sense now ...

I mean, everytime I get in a fight with a pro MMA guy I always get knocked out, so the "logical" extrapolation is no difference between MMA fighters, thus all MMA fights should be draws, but they're not, so they're all rigged.  (after all, all those guys have a financial stake in the industry, so it's all a big conspiracy)

Until you can prove to me with punch force measurements that MMA fighters are different, let's just assume they're all the same and all fights with a winner are rigged.


----------



## bigshot

Glmoneydawg said:


> I'm betting all 5 of your amps where solid state....kinda takes you out of this argument my friend .....ever owned a modern tube amp?



No, no interest in hard wired coloration. I can do that with DSPs if I want it and it will be completely adjustable.


----------



## Arpiben

jagwap said:


> I wasn't refering to RF, but another aspect outside of "conventional" measurements.
> 
> I won't name other brands as deficient, as that would be unprofessional.



I regret that you have not or can not share any DAC measurements showing the benefits.


----------



## csglinux

I might have a DAP to add to @bigshot's collection. Something that's puzzled me for a while is an effect I hear very strongly via the headphone-out of my QP1R when using the SE846. It's in the first 5 seconds of the Glass Hammer track "Towards Home We Fled" from the "Perilous" album. The bass player (Steve Babb) hits an F2 (~87.3 Hz) at the end of the second bar. He bends the string on the fretboard ever so slightly, but it's more or less 100% in tune via any of my other sources. That same note (F2) on my QP1R is notably flat. BTW, if I use a higher-impedance headphone, or I use a line-out from the QP1R->KSE1500 analog-in, the intonation is perfect again, so it seems like it's not the QP1R's DAC, but more likely the QP1R's current mode amp (along with, perhaps, the wild impedance swings of the SE846?) that does something with the timing that alters the pitch of that bass note. I've never found a plausible scientific explanation for what's going on.

Anybody got any thoughts?


----------



## GrussGott (Dec 8, 2018)

Back on the topic of measurements, this interview with industry legend Dan D’Agostino is super interesting:

TLDR: measurements are good design guides but not definitive for sound quality



I suspect this same understanding (or lack thereof) of measurements is also happening with cables, DACs, and everything else audio


----------



## bfreedma

GrussGott said:


> Back on the topic of measurements, this interview with industry legend Dan D’Agostino is super interesting:
> 
> TLDR: measurements are good design guides but not definitive for sound quality
> 
> ...





Someone with a financial interest in selling ultra expensive amps which show no measurable audible advantages over lower priced amps states measurements aren’t definitive.  Shocking...

If I was selling monoblocks that sell for $130k a pair, I’d use the same sales and marketing tactics.


----------



## Brooko (Dec 8, 2018)

GrussGott said:


> Back on the topic of measurements, this interview with industry legend Dan D’Agostino is super interesting:
> 
> TLDR: measurements are good design guides but not definitive for sound quality
> 
> ...




Please stay on topic.  I believe the thread topic is why USB cables "make such a difference".  I think we've established so far that unless they are produced out of spec, or the DAC they are feeding is out of spec / badly designed - then they don't.

Or at least that's my read of it so far.


----------



## Steve999

csglinux said:


> I might have a DAP to add to @bigshot's collection. Something that's puzzled me for a while is an effect I hear very strongly via the headphone-out of my QP1R when using the SE846. It's in the first 5 seconds of the Glass Hammer track "Towards Home We Fled" from the "Perilous" album. The bass player (Steve Babb) hits an F2 (~87.3 Hz) at the end of the second bar. He bends the string on the fretboard ever so slightly, but it's more or less 100% in tune via any of my other sources. That same note (F2) on my QP1R is notably flat. BTW, if I use a higher-impedance headphone, or I use a line-out from the QP1R->KSE1500 analog-in, the intonation is perfect again, so it seems like it's not the QP1R's DAC, but more likely the QP1R's current mode amp (along with, perhaps, the wild impedance swings of the SE846?) that does something with the timing that alters the pitch of that bass note. I've never found a plausible scientific explanation for what's going on.
> 
> Anybody got any thoughts?



I’ll check it out on my equipment through any streaming services I have that have the track. Plus as I always say it’s a chance to get to know some new music.


----------



## GrussGott (Dec 9, 2018)

Brooko said:


> Please stay on topic.  I believe the thread topic is why USB cables "make such a difference". * I think we've established so far that *unless they are produced out of spec, or the DAC they are feeding is out of spec / badly designed - then they don't.
> 
> Or at least that's my read of it so far.



No, when it comes to USB cables:

(*1.) We've established there are a lot of speculative opinions *based on assumptions, guesses, and personal experience since we have zero definitive research and/or data
*(2.) We've also established a lot of people pretend to be experts*, many wish they were experts, and a few have giant needy egos needing constant feeding (and come here to feed)
*(3.) Finally, we've established there are a lot audiophiles easily discombobulated and frightened by uncertainty *and ambiguity (which causes them to make up conclusions, panic and/or lash out)

But as for any data-driven definitive conclusion on USB (or digital cables in general), we've established nothing.

It's just science.


----------



## Brooko

GrussGott said:


> No, when it comes to USB cables:
> 
> (1.) We've established there are a lot of speculative opinions based on assumptions, guesses, and personal experience since we have zero definitive research and/or data
> (2.) We've also established a lot of people pretend to be experts, many wish they were experts, and a few have giant needy egos needing constant feeding (and come here to feed)
> ...


I suggest you go back through the thread then - perhaps a little less selective reading?

There has been at least a set of objective data which shows no measurable difference, and every instance of anecdotal evidence appears to have been debunked.  Or can you point me to specific posts in the thread which show a measurable difference which can be attributed to cables?


----------



## bigshot

He’s making it all up to self validate


----------



## GrussGott (Dec 9, 2018)

Brooko said:


> I suggest you go back through the thread then - perhaps a little less selective reading?
> 
> There has been at least a set of objective data which shows no measurable difference, and every instance of anecdotal evidence appears to have been debunked.  Or can you point me to specific posts in the thread which show a measurable difference which can be attributed to cables?



Being this is the science thread, I feel honor-bound to point out everything in your post adds up to "we're guessing and speculating based on the anecdotes of amateurs".

In my scientificalogical experience, "hey that one time that dude did some stuff with some machines and such" doesn't cross the conclusive and definitive bar.

Further, pretending (or deluding yourself) that random amateur messing about has established anything is misleading at best.  (although if he was wearing a white coat and safety glasses it would make it more fun)

In short, *we have zero conclusive data of anything when it comes to cables*; just guesses, speculations, amateur experiments, and bunch of either misunderstanding, fear and/or discomfort with that uncertainty.  That should be the one place we can all fully agree ...

Because it is, scientifically, the state of affairs, and the only thing actually validated.


----------



## GrussGott

bigshot said:


> He’s making it all up to self validate



It's funny you keep accusing me of having an opinion when I've been pretty consistent that i'm not an expert in:

* Electrical transmission
* Electrical properties of metals
* Cable design & geometry
* Digital signals processing
* DAC and digital audio electronics design
* Human hearing and sound waves

Thus, it's not only impossible for me (or anyone here) to have a definitive opinion, it's unethical for me (or anyone here) to give definitive advice. 

That said, I have no problem sharing my experiences, my amateur's speculation of why, and disclaiming that my experience is likely not predictive of anyone else's.


----------



## Triode User

GrussGott said:


> .....In my *scientificalogical* experience ...



Is that even a word?


----------



## bigshot (Dec 9, 2018)

I have enough experience to form an opinion, and I'm happy to offer advice. Spending money on fancy USB cables is a waste of money. USB cables either work or they don't. There's no in-between. Any cable that performs to USB spec will do the job the same as any other cable.


----------



## GrussGott (Dec 9, 2018)

bigshot said:


> *I have enough experience to form an opinion, and I'm happy to offer advice. *Spending money on fancy USB cables is a waste of money. USB cables either work or they don't. There's no in-between. Any cable that performs to USB spec will do the job the same as any other cable.



Sure, but that's your amateurs speculative opinion, which you should be sure to tell people when they ask  ... although I'm assuming you're not trying to misrepresent yourself ...

Any competent engineer or scientist _who's been paid to make decisions that bet people's jobs, money, or lives_, knows the danger and folly of pretending an amateur opinion is a fact.

That's my bias: nobody here knows - just a bunch of amateur guessing.


----------



## bigshot

Uh... I'm not an amateur. I have worked in sound recording, editing, and mixing in a professional capacity if that makes any difference.


----------



## GrussGott (Dec 9, 2018)

bigshot said:


> Uh... I'm not an amateur. *I have worked in sound recording, editing, and mixing in a professional capacity* *if that makes any difference.*



It does not.  You're an amateur on this topic, and the fact that you don't understand that is how we know it's true.

Any competent engineer or scientist _who gets paid to make decisions that affect people's jobs, money, or lives_ would never misrepresent themselves or their knowledge, and understand the difference between bet-your-money facts and we-don't-know-yet guesses.

That's why they're paid to make decisions and you are not.


----------



## Killcomic

Really? You lot are arguing over USB cables?
It's a bloody digital signal. A "better" cable won't make your 0s rounder and your 1s straighter. 
Digital either works or doesn't. 

Seriously, audiophiles are like medieval people, believing utter nonsense despite bugger all evidence.

I could pick up a rock from the garden, wrap it in copper wiring then claim it improves digital processing and sell it for $300. I bet people here will talk about how it improves soundstage and tightens up the bass.


----------



## GrussGott (Dec 9, 2018)

Killcomic said:


> A "better" cable won't make your 0s rounder and your 1s straighter. Digital either works or doesn't.



Sure, but in our defense that's only because that's not true.  Mostly that's likely due to the USB audio spec (as opposed to the USB bulk spec for file transfer) guaranteeing bandwidth but no error correction, thus errored bits in a word (noise) or mis-timed bits (jitter) can get directly converted by the DAC into analogue ... but really we don't know.  (no matter what the inbred groupthink would tempt you to believe)

So feel free to bust out your source-side / DAC-side data analysis showing you're right, but realize you'll have to know the XMOS or C-media USB receiver chip firmware code, which is a trade secret, so you'll likely be easily identifiable by them, and nobody here would ask you to break your contract.

Or ... you don't have that data, don't know what that code says, and you're guessing.  (but I get it's fun to believe everyone is just a big ole dope and you're such a smartie!)

My bet is on the latter.


----------



## Killcomic (Dec 9, 2018)

GrussGott said:


> Sure, but in our defense that's only because that's not true.  Mostly that's likely due to the USB audio spec (as opposed to the USB bulk spec) guaranteeing bandwidth but no error correction, thus errored bits in a word (noise) or mis-timed bits (jitter) can get directly converted by the DAC into analogue ... but really we don't know.  (no matter what the inbred groupthink would tempt you to believe)
> 
> So feel free to bust out your source-side / DAC-side data analysis showing you're right, but realize you'll have to know the XMOS or C-media USB receiver chip firmware code, which is a trade secret, so you'll likely be easily identifiable by them, and nobody here would ask you to break your contract.
> 
> ...


I've been working  on computers for decades. Mine is an educated guess as opposed to one  formed by marketing material. May I point out you dont have data either?

Actally, you want data? Transfer a file over usb and see how many CRC errors you get with different cables?
Hint: None.

Watch a 1080p, or even 4k, video over USB and see how much jitter and artifacts you get compared to the original file.
Hint: None.

You can transmit 1080p video, which requires a lot more bandwidth, over a simple cable that you can buy for $10.

The maximum bandwidth is determined by the host, not the cable.
USB 2 is 60 MB per second and USB 3 is 640 MB per second. The bottleneck is not the cable but the controller type.

Please tell me how you need a special USB cable to transmit music.


----------



## bfreedma (Dec 9, 2018)

GrussGott said:


> It does not.  You're an amateur on this topic, and the fact that you don't understand that is how we know it's true.
> 
> Any competent engineer or scientist _who gets paid to make decisions that affect people's jobs, money, or lives_ would never misrepresent themselves or their knowledge, and understand the difference between bet-your-money facts and we-don't-know-yet guesses.
> 
> That's why they're paid to make decisions and you are not.




You keep referring to working in an engineering field where lives are at stake and therefore no guesswork is involved.  Can we dispense with that fallacy?

Let’s take an air launched missile as an example - certainly lives are at risk.  Air to air or air to ground present the same or similar variables that need to be accounted for and to suggest that every permutation is tested and the outcomes fully known isn’t reality.  While many are tested for, most combinations are rationalized based on “guesses” made via our current knowledge of the science involved.

To intimate that all scenarios are fully understood and accounted for would require all possible permutations of the following to be tested - I fully acknowledge that this is not the complete list.  Temperature, atmospheric pressure, wind speed, humidity, continuous and variable wind shear, airborne particulate type, airborne particulate volume, and numerous others.

Then, every possible permutation of that list would need to be tested against every situational and operational variables, including pressure waves and temperature gradients resultant from other ordinance in the area of operations, physical and electronic countermeasures, and many more - that should be a long enough list to make the point.

In reality, there are actually far fewer environmental variables in USB data transport than the scenario described above.  While neither are fully permutationally tested, both are based on enough known science to be rationally assessed and for reasonable conclusions/outcomes to be determined.  At some point, finite data sets require exception based programming to account for unknown conditions/variables.  Or more basically stated, guesses to be made based on the best information available.  If and when new information is available, change may be required.


----------



## Killcomic

bfreedma said:


> You keep referring to working in an engineering field where lives are at stake and therefore no guesswork is involved.  Can we dispense with that fallacy?
> 
> Let’s take an air launched missile as an example - certainly lives are at risk.  Air to air or air to ground present the same or similar variables that need to be accounted for and to suggest that every permutation is tested and the outcomes fully known isn’t reality.  While many are tested for, most combinations are rationalized based on “guesses” made via our current knowledge of the science involved.
> 
> ...


That's why CRC checks exist, to confirn data integrity.


----------



## bfreedma

Killcomic said:


> That's why CRC checks exist, to confirn data integrity.



Agreed, though CRC checks aren’t generally done on audio data during playback via USB.  That said, the error rates identified on audio streams in the studies I’ve seen are low enough to be considered negligeible and not audible.  Either way, as you suggested earlier, a cable wouldn’t be the source or remediation point for those errors in normal use cases.


----------



## bigshot (Dec 9, 2018)

I really should learn my own lesson and stop addressing these self important internet duffers.

There's no reason to worry about data transfer in a USB cable unless you're experiencing obvious problems like stuttering and dropped connections. And if that's the case, the source of your problem is almost certainly not the cable. And in the unlikely case that the cable is the problem, just replacing it with a standard Amazon Basic USB cable will fix the problem.


----------



## GrussGott (Dec 9, 2018)

bfreedma said:


> You keep referring to working in an engineering field where lives are at stake and therefore no guesswork is involved.  *Can we dispense with that fallacy?*



There are many fields that require professional licenses:
* Law
* Civil Engineering
* Medicine
* Electrical Engineering
* Accounting
* Aviation

The reason for this is because the advice those professionals provide risks people's money, jobs, or lives.  For example, take a producer of pacemakers: they have to be pretty fecking careful with their electronics since they're betting shareholder money, company jobs and careers, and the recipients lives.  Aircraft mechanics doing maintenance on a two-engine aircraft about to fly 3000 miles over an ocean have to be pretty sure why that electrical fault happened, and why it's not going to happen again.  They sign their names attesting to it, and you've likely bet your life on their decision.

The point is, there are measure twice, cut once professions, and people who work in those professions learn the difference between what is known and what is guessed.

Anyway, the answer to your question is, no we can't.


----------



## bigshot (Dec 9, 2018)

I think the internet should have a minimum standard for posting.

Upgrading USB cables is a lousy way to improve your sound system. It is pure bling with no audible benefit. You might as well stud your headphones with rhinestones and plate your DAC with 14k gold. It's all flash and no substance.


----------



## bfreedma

GrussGott said:


> There are many fields that require professional licenses:
> * Law
> * Civil Engineering
> * Medicine
> ...




Either you didn’t read my post or chose to ignore the content because it’s clear that within even the riskiest of engineering and science fields, guesswork, even if educated, is required.  Your strawman resoponse listing fields requiring accredation/certification doesn’t change that.  Even your own words, stating aircraft mechanics “have to be pretty sure” indicates there is educated guesswork involved.  

That’s not to discredit what they do, just to highlight that your claim that those fields operate solely on established and settled science is indeed a fallacy.


----------



## bigshot (Dec 9, 2018)

How can one person waste so much time and energy? It's like a black hole sucking everything into nothingness. We seem to attract black holes lately. I don't have time to waste on foolishness.

Perhaps the solution is to just reply with...

No.*


* see above

Either way your read that it has the same effect.


----------



## Killcomic

bigshot said:


> We seem to attract black holes lately. I don't have time to waste on foolishne



And in an audiophile forum of all places! Bastions of logic and common sense.... Wait....


----------



## bfreedma (Dec 9, 2018)

bigshot said:


> How can one person waste so much time and energy? It's like a black hole sucking everything into nothingness. We seem to attract black holes lately. I don't have time to waste on foolishness.
> 
> Perhaps the solution is to just reply with...
> 
> ...




Technically, black holes don’t suck things into nothingness.  Once inside the schwarzschild radius...

I’m assuming you weren’t referring to my responses.  But you do have a point about not investing the time.  I just don’t like leaving some of the navel gazing unchallenged in case others drop into this thread without context.


----------



## jagwap

GrussGott said:


> Back on the topic of measurements, this interview with industry legend Dan D’Agostino is super interesting:
> 
> TLDR: measurements are good design guides but not definitive for sound quality
> 
> ...




Now this is an interesting case. Years ago we reverse-engineered one of his Krell amps. It did not have zero feedback as claimed, but had around 3dB of feedback around the output stage only. This figure is interesting, as if you look up the chart in John Lindsea-Hood's book on amplification, 3 dB is the point where feedback not only increases distortion, it adds the most distortion. Whether this is true for the Krell's unusual topology I cannot say, but we also listened to it. Used them (as they were monoblocks) as a benchmark in the listening room for a while. However it became clear that wile they sounded good, quite enjoyable, they were coloured, particularly in the bass. They measured fine by the way: flat frequency response, reasonable THD etc.

We were not the only group that found this. Several other companies moved away from Krell as a reference as Krell moved towards a less neutral sound. This was deliberate I think, as their early stuff was great.

I know this is contrary to my mentioning other brands comment from before, but this was a brand that deliberately moved away from neutral transparent reproduction to a coloured sound.


----------



## JRG1990

102 pages and no objective data showing usb cables having an audible effect.
Just the usual rubbish about  science doesn't know everything and can't prove anything.


----------



## GrussGott (Dec 9, 2018)

JRG1990 said:


> 102 pages and no objective data showing usb cables having an audible effect _*or don't*_.
> Just the usual rubbish about  science doesn't know everything and can't prove anything.



FTFY

Also, answering the USB cable question isn't a science question - we just need an analysis of what was sent from the source, what the chip received, and what the chip output across a representative set of DACs in representative environments.  Boom, answered.

Since we don't have that, everyone is arguing over their speculations, and many don't even realize they're speculating, despite the fact this is the science thread.


----------



## Killcomic

GrussGott said:


> FTFY
> 
> Also, answering the USB cable question isn't a science question - we just need an analysis of what was sent from the source, what the chip received, and what the chip output across a representative set of DACs in representative environments.  Boom, answered.
> 
> Since we don't have that, everyone is arguing over their speculations, and many don't even realize they're speculating, despite the fact this is the science thread.


Um, you do realise that digital audio data is just data, right?
There are decades of evidence supporting the point that a cheap USB cable works as well as an expensive cable. Otherwise we would be getting CRC errors all over the place when transferring data over USB. Portable hard drives would be unusable without an expensive USB cable.


----------



## GrussGott (Dec 9, 2018)

GrussGott said:


> FTFY





Killcomic said:


> Um, you do realise that digital audio data is just data, right?



Ummm you do realize how science works, right?  Like how science facts are easily provable?

(oh and you do realize portable hard drives use the USB bulk spec (08h) which has error correction - CRC vs. USB audio transfers which use the USB audio spec (o1h) which is live with no error correction right?  i mean I'm assuming you do as it's the most basic principle here - and if you didn't understand even the most basic principle of USB audio, but were cocking off about your knowledge and certainty of 'digital audio' you'd look pretty dumb.  So I'm assuming you did your homework to learn the basics before speaking about something you clearly didn't know the first thing about.)

So, hey, if you have decades of evidence, put it all together for for us into scientific fact.  (don't forget to explain that XMOS code).

Go!


----------



## bfreedma

GrussGott said:


> Ummm you do realize how science works, right?  Like how science facts are easily provable?
> 
> (oh and you do realize portable hard drives use the USB bulk spec (08h) which has error correction - CRC vs. USB audio transfers which use the USB audio spec (o1h) which is live with no error correction right?  i mean I'm assuming you do as it's the most basic principle here - and if you didn't understand even the most basic principle of USB audio, but were cocking off about your knowledge and certainty of 'digital audio' you'd look pretty dumb.  So I'm assuming you did your homework to learn the basics before speaking about something you clearly don't know the first thing about.)
> 
> ...




You edited the post you quoted to change it’s context and make it appear as if the OP wasn’t aware of data correction and CRC as applied to audio vs bulk data transmission?

That’s very unethical of you.  No reason to waste any more time here.


----------



## Killcomic

Wow, the snake oil is strong with this one.


GrussGott said:


> Ummm you do realize how science works, right?  Like how science facts are easily provable?
> 
> (oh and you do realize portable hard drives use the USB bulk spec (08h) which has error correction - CRC vs. USB audio transfers which use the USB audio spec (o1h) which is live with no error correction right?  i mean I'm assuming you do as it's the most basic principle here - and if you didn't understand even the most basic principle of USB audio, but were cocking off about your knowledge and certainty of 'digital audio' you'd look pretty dumb.  So I'm assuming you did your homework to learn the basics before speaking about something you clearly didn't know the first thing about.)
> 
> ...


May I remind you that it's you who is trying to convince others of what it basically snake oil?


----------



## GrussGott (Dec 9, 2018)

Killcomic said:


> Wow, the snake oil is strong with this one.
> 
> May I remind you that it's you who is trying to convince others of what it basically snake oil?



Well, no, because that wouldn't be true.  Here's why:

If you were saying, "hey, in my experience usb cables don't do jack, and nothing I've ever seen shows me they could" that's totally cool, because that's your experience and your amateur's opinion of why.

But if you're making a claim of a scientific fact like: "it's a fact USB cables cannot affect audio quality", then you should be able to easily prove that.   But you can't prove that easily or otherwise, all you can do is share anecdotal data and amateur opinions which is not proof.

For me, I'm saying USB cables worked for me, I have thoughts on why, but those are guesses; thus my advice is try them for free, or don't try them, because my experience is only 1 anecdote not proof of anything.

See how it's you making an unsubstantiated claim that you can't prove?

I sure hope so, because for the science thread there's very little understanding of how science actually works:  Science facts are provable, everything else is guesswork.


----------



## Killcomic

GrussGott said:


> Well, no, because that wouldn't be true.  Here's why:
> 
> If you were saying, "hey, in my experience usb cables don't do jack, and nothing I've ever seen shows me they could" that's totally cool, because that's your experience and your amateur's opinion of why.
> 
> ...


You are making the claim that digital signals transfer better over more expensive cables.
You are the one going againt established  knowledge of digital transfers. It is you making the extraordinary claim, hence it is your responsibility to provide the evidence.


----------



## GrussGott

bfreedma said:


> You edited the post you quoted to change it’s context and make it appear as if the OP wasn’t aware of data correction and CRC as applied to audio vs bulk data transmission?
> 
> That’s very unethical of you.  No reason to waste any more time here.



How could I edit his post?  Go look, that dude said:

_"There are decades of evidence supporting the point that a cheap USB cable works as well as an expensive cable. Otherwise we would be getting CRC errors all over the place when transferring data over USB. Portable hard drives would be unusable without an expensive USB cable."_​
It would appear he doesn't understand we're talking about the USB audio spec, not USB bulk-mode, otherwise why mention CRC or hard drives?


----------



## GrussGott (Dec 9, 2018)

Killcomic said:


> *You are making the claim that digital signals transfer better over more expensive cables.*
> You are the one going againt established  knowledge of digital transfers. It is you making the extraordinary claim, hence it is your responsibility to provide the evidence.



Dude, I am making no such claim, nor have I ever posted such a claim, quite the opposite.

as for "the established knowledge of digital transfers", yeah, I'm "going against" "digital transfers" since we talking UAC not USB mass storage aka bulk-mode transfer.  They are two totally different things governed by different specs.

USB audio is class 01h which is an isochronous transfer, and USB mass storage is class 08h, which is a bulk transfer.  they're different:

_*There are four sorts of IN and OUT-transfers in USB*: Bulk, Isochronous, Interrupt, and Control transfers.

*A bulk transfer *is used to reliably transfer data between host and device. All USB transfers carry a CRC (checksum) that indicates whether an error has occurred. On a bulk transfer, the receiver of the data has to verify the CRC. If the CRC is correct the transfer is acknowledged, and the data is assumed to have been transferred error-free. *If the CRC is not correct, the transfer is not acknowledged and will be retried.*

I*sochronous transfers *are used to *transfer data in real-time *between host and device. When an isochronous endpoint is set up by the host, the host allocates a specific amount of bandwidth to the isochronous endpoint, and it regularly performs an IN- or OUT-transfer on that endpoint. For example, the host may OUT 1 KByte of data every 125 us to the device. Since a fixed and limited amount of bandwidth has been allocated, *there is no time to resend data if anything goes wrong.* *The data has a CRC as normal, but if the receiving side detects an error there is no resend mechanism.*_​


----------



## Killcomic

GrussGott said:


> Dude, I am making no such claim, nor have I ever posted such a claim, quite the opposite.
> 
> as for "the established knowledge of digital transfers", yeah, I'm "going against" "digital transfers" since we talking UAC not USB mass storage aka bulk-mode transfer.  They are two totally different things governed by different specs.
> 
> ...


Yes, I understand that, but how many errors do you encounter with a nirnal cable vs an expensive one.
Does the error rate drop dramatically? Are there errors to begin with?


----------



## GrussGott (Dec 9, 2018)

Killcomic said:


> Yes, I understand that, but *how many errors do you encounter with a nirnal cable vs an expensive one.*
> Does the error rate drop dramatically? *Are there errors to begin with?*



I don't know, you don't know, nobody here knows - that's the science.  And even if we did know, it would be only for our equipment, in our environments at that time.

Thus until someone can do a source-to-DAC-in/out data analysis of a representative set of sources and DACs, who knows?  Not to mention nobody, saving a few, understand the chip firmware which is why Schiit created their own USB special interest group, so they could create their own USB implementation and remove the handcuffs of standard chipsets.

Thus all we can do is try stuff and see if it works for our environment, equipment, and ears - and since reputable cable companies allow you to try them for months for free why wouldn't you?  I did and they worked for me, but I live high up in a major downtown with absolute shiit-tons of EMI.  Right now I'm picking up 46 wi-fi networks and 5 cell networks and who knows how many towers and other crap and that's just from a 1 second glance.  In no way am I claiming my anecdote proves anything (other than open-minded people have better audio experiences)

Look, i'm sorry you thought you had it all figured out, but you just don't cause if you did you could prove your claim.


----------



## Killcomic

GrussGott said:


> I don't know, you don't know - that's the science.  And even if we did know, it would be only for our equipment.
> 
> Thus until someone can do a source-to-DAC-in/out data analysis of a representative set of sources and DACs, who knows?  Not to mention nobody, saving a few, understand the chip firmware which is why Schiit created their own USB special interest group, so they could create their own USB implementation and remove the handcuffs of standard chipsets.
> 
> ...


You'd be surprised at how little it bothers me if I'm wrong, specially about this.
I still maintain that the cable makes no difference unless out of spec, but if I'm wrong, which is always a possibility, I'd be glad to have learnt something new.


----------



## GrussGott

Killcomic said:


> You'd be surprised at how little it bothers me if I'm wrong, specially about this.
> I still maintain that the cable makes no difference unless out of spec, but if I'm wrong, which is always a possibility, I'd be glad to have learnt something new.



That's pretty awesome, you're probably the first person here with the humility and courage to say that.

Until we know, here's to learning new stuff!  :: clink, clink ::


----------



## Killcomic

GrussGott said:


> That's pretty awesome, you're probably the first person here with the humility and courage to say that.
> 
> Until we know, here's to learning new stuff!  :: clink, clink ::


Well it's just a hobby, isn't it?


----------



## bigshot

There’s no reason to believe USB cables make an audible difference. But I suppose the moon could actually be made of green cheese and science has been lying to us since Apollo 11


----------



## Brooko (Dec 10, 2018)

GrussGott said:


> Being this is the science thread, I feel honor-bound to point out everything in your post adds up to "we're guessing and speculating based on the anecdotes of amateurs".
> 
> In my scientificalogical experience, "hey that one time that dude did some stuff with some machines and such" doesn't cross the conclusive and definitive bar.
> 
> ...



I don't know why I'm bothering because you'll dismiss it again - but I'll try anyway:


Objective real evidence:
http://archimago.blogspot.com/2013/04/measurements-usb-cables-for-dacs.html


More objective real evidence:
https://www.audiosciencereview.com/...s/do-usb-audio-cables-make-a-difference.1887/
Note that they also talk about audibility here, and the measurements confirm that any differences would be beyond the threshold of audibility unless packets were being dropped.


Further discussion about the tests in (1) above
http://archimago.blogspot.com/2013/06/musings-about-those-usb-cable-tests.html


Commentary - well worth reading - from an engineer - he talks cables in the section on Audiophile Digital Cables
https://medium.com/@skikirkwood/truth-lies-and-fraud-in-the-audiophile-world-a365e56c97c4


Commentary from Mark Waldrep - Studio owner, does this for a living, and in audio world his set-up is "mission critical"
http://www.realhd-audio.com/?p=5561


> Most of the comments I’ve read around the web devolve into the same age-old argument about whether cables make a difference in the fidelity of your system or not. Intelligent people on both sides of the debate make their cases without any convincing anyone to change their mind. Believers will continue to believe while those that tend to the “show me data” end of the spectrum remain steadfast in their rejection of $1000 HDMI or USB cables. You all know where I stand on this issue. Don’t buy cables thinking they are going to improve the fidelity of your system. If you like the wonderful windings, the cool colors, the heavy connectors, or the status of a branded cable, then by all means spend the money…but don’t expect the sound to improve. There are plenty of other things you can do…at far less cost…that will affect your sound.
> 
> A functioning digital audio interface cable (AES-EBU, S/P DIF, SDIF, USB, or HDMI) cannot and should not alter the bit stream connecting a digital source component to a digital destination. All those “believers” who challenge this important fact are living in a dream world. Simply stating that hearing is believing doesn’t cut it. I know there are many individuals, reviewers, companies, consumers, and publications that profess otherwise but they all have a vested interest in perpetuating this myth…and others. Professional audio studios don’t use expensive cables or power cords so why should you?
> 
> *I can’t say that I’ve tested every permutation, format, cable, connector, or material but I did compare the data delivered by a $300 USB cable and a $5 USB and found that each successfully delivered exactly the same data. The audio from the different cables when the polarity of one was reversed completely and exactly nulled the other. The both accomplished their tasks with equal “fidelity”…as expected.*



Right - I've shown from multiple sources that in every instance, the USB cables in question make zero audible effect.

So please - just deliver ONE - repeatable measurable difference using two cables which both meet the audio standard and that produce audible differences.  Just one.

And to reference your above (pitiable) answer:

The measurements aren't anecdotes of amateurs - at least 3 of them are professionals in the industry
Its not conclusive, but in the absence of any contradictory measurable data in this thread, and the fact that no one has produced any (my internet search definitely didn't turn up any), it does point to a repeatable pattern
While this is not my field - it is for the people I've quoted - and please lay off the smarmy "deluding" comments.  The only one doing it appears to be you.  It's obvious, and it denigrates from the purpose of the thread.  Please have some respect for the people actually looking for enlightenment
I have shown documented real evidence in the links.  They are not guesses.  They are not speculations.  And if you want to call people like Mark Waldrep amateur or deluded - then I don't need to go any further.


----------



## old tech

bigshot said:


> There’s no reason to believe USB cables make an audible difference. But I suppose the moon could actually be made of green cheese and science has been lying to us since Apollo 11


Well, they would say that the Apollo ll and the moon landing was a lie.


----------



## Killcomic (Dec 10, 2018)

If this conversation moves onto moon landing conspiracies, I'm getting the hell out of here.


----------



## JRG1990 (Dec 10, 2018)

GrussGott said:


> FTFY
> 
> Also, answering the USB cable question isn't a science question - we just need an analysis of what was sent from the source, what the chip received, and what the chip output across a representative set of DACs in representative environments.  Boom, answered.
> 
> Since we don't have that, everyone is arguing over their speculations, and many don't even realize they're speculating, despite the fact this is the science thread.



I'm only interested in how a  usb cable would affect the sound quality we hear ,so we would measure , jitter , thd , signal to noise  etc.

These measurements have been posted and show no audible  differences to prove otherwise you need to post measurements or any objective data rather than just saying the data that has been posted is wrong.


----------



## bigshot

I guess he's abandoned the claim that he did a controlled test and was able to consistently discern a difference between USB cables. I suspected that was made up from the beginning, but I gave him the benefit of the doubt. No need to do that any more!


----------



## JRG1990

His gone from trying to convince us usb cables make a audiable difference, to no one could possibly know.


----------



## My Little Phony

One shall be sacrificed by getting whipped with an Audioquest Coffee USB cord.


----------



## bigshot

Would you like cream and sugar with that snake oil?


----------



## castleofargh

while I didn't enjoy all the desperate fishing for possibilities, at least saying we don't know everything is technically true. so it's much better than making nonsensical claims about what absolutely improves usb cables, like using one with silver or some funny claims like that(which were posted on this topic!!!!).
so instead of just mocking someone, something I can only let you do for so long as a modo, let's appreciate that some degree of uncertainty makes for a very good starting point, and an almost equally good landing place for a topic concerned with facts. 
those who want to have faith in extraordinary marketing and sighted impressions, instead of relying on evidence, will go purchase their weird expensive stuff anyway. and it's their right to do so. I believe our role is simply to make sure they don't drag too many fellow members into paying for objective improvements that were never objectively demonstrated(my nice way of saying that they're probably not improvements at all).
I personally would need some very solid objective evidence before I put more than... maybe 50$ if it's really pretty, into a USB cable. even if a 400$ USB cable could effectively improve my audio audibly and objectively, and I got actual evidence of it(for a change), there's always going to be a lot more that I could do for my audio experience with 400$.


----------



## bigshot

"We don't know everything, so we can't know anything." That is the argument... along with a whole lot of goal post shifting.

I don't see why a product can't prove its effectiveness 100%. I'm even willing to help them do that. I have mono price and Amazon Basics USB cables. Provide us with one that sounds different than that and we will pull together the resources of Sound Science to organize a listening tests and measurements. Put up or shut up.


----------



## Redcarmoose

Well, I just finished 8.3 days of nonstop USB cable burn-in. It’s the first USB cable to sound dramatically different in sighted tests. Probably have my wife help with the non-sighted testing to see if I can distinguish the $170 AQ Carbon USB cable from a group of $5 cables. 

I figure the test will be pretty simple I’m going to try 20 different listens of the exact part of the exact same song. Each time I will write down if I feel the more expensive cable was put in place. 

My wife is tricky, she may include expensive cable on the second listen of the song and never use it again. I’m explaining to her it has to be as random as possible. 

I’m fairly sure I’m not going to be able to distinguish the more expensive cable. But the reality here is I simply don’t take anyone’s idea of the subject as truth until I hear it or don’t hear a difference for myself. If there is no difference I’ll keep the cable. But you also will not find me relaying much else about my test except the end results in this thread. 

I’m not standing on any soap box, and have nothing to prove, other than getting the best sound possible with-in my expenditure goals. 

I figure this is a subject people need to learn about on their own, as there seems to be strong opinions on both sides.


----------



## old tech

Redcarmoose said:


> Well, I just finished 8.3 days of nonstop USB cable burn-in. It’s the first USB cable to sound dramatically different in sighted tests. Probably have my wife help with the non-sighted testing to see if I can distinguish the $170 AQ Carbon USB cable from a group of $5 cables.
> 
> I figure the test will be pretty simple I’m going to try 20 different listens of the exact part of the exact same song. Each time I will write down if I feel the more expensive cable was put in place.
> 
> ...



I wouldn't place both sides at the same level.

There are opinons on one side, and uniformed at that, vs factual understanding based on technical knowledge and controlled tests.


----------



## My Little Phony (Dec 11, 2018)

The AQ carbon USB-cable was an interesting contender to the audiophil-blasphemic standard usb cord 

German test translated:
Similar to the AQVOX, *the carbon* also makes a lot of fun right from the start. It plays dynamically, places instruments vividly in the room and also works out details nicely.

In direct comparison with the approximately equally expensive German competitors, however, the US cable fell back somewhat for our taste: "The heavens tell the glory of God" did not seem so relaxed and made it a bit harder for the listener, the lyrics of the individual To follow tone of voice. The AQVOX also impressed with the finer tones and sub sounds of acoustic instruments, be it the piano on "I'll be your baby tonight" or the guitar on Brokeback Mountain. Here, the carbon could not quite keep up with the reverb and thus the size of the stage.

There are no outliers with the Audioquest USB cables: Every additional investment brings a sonically better result. It is no surprise for high-end connoisseurs that roughly the same amount of progress is required to double the price every time. Set yourself a limit and try out all the possible cables in your chain. But beware: once you've heard a diamond, every step back is damn hard.


Audioquest philosophy:
In 1982 Sony gave us "Perfect sound forever," along with the attitude that, "it's just digital, so all CD players sound the same." That was disproved and qualitative differences between players became accepted truth. Next came separate transport and DAC combos, which brought with it the attitude that "all S/PDIF digital audio cables sound the same..." until that too became disproved. Now the frontier has moved once again. Is digital audio really just ones and zeros? We don't believe so, and once you've had a chance to listen to Carbon USB, you won't think so either..


Note:

I personally finished testing different digital audio and video-cables. If a cable dont suffer from manufacturing issues and provides the standard specs it will perform as good as any other cable.


----------



## Redcarmoose (Dec 11, 2018)

My Little Phony said:


> The AQ carbon USB-cable was an interesting contender to the audiophil-blasphemic standard usb cord
> 
> German test translated:
> Similar to the AQVOX, *the carbon* also makes a lot of fun right from the start. It plays dynamically, places instruments vividly in the room and also works out details nicely.
> ...


Well strange as it may sound I could actually do a comparison at this point, comparing the Carbon to regular $5 drug store cables.

Of course all these ideas are in sighted tests.........which again brings up the bewildering convoluted-whirlwind of psychological-confusion.

????


And my question asks........if placebo is a perception distorter, then why isn’t it a perceived perfection? Meaning at times the Carbon revealed an almost too bright and brittle treble. As not only in sighted tests was the Carbon noticeably more clear; at times the treble almost became over accentuated?

And of course to buy any audio product we wade into the murk of sales tomfoolery. 

What with all the hot-buttons in audiophile words, used in all the best places. The lead-in, the supposed observation, the factual reinforcement of findings...........then finally the asking for the sale.

The sales force is strong in the USB world of audiophile cables.


----------



## bigshot (Dec 11, 2018)

Redcarmoose said:


> It’s the first USB cable to sound dramatically different in sighted tests.



I can guarantee it isn't the first. If you come up with a USB cable that has coloration, I would appreciate being able to borrow it for testing by the group. It would be interesting to find out exactly how it is altering the sound.

Placebo is a normal human trait. So is bias. If we didn't have those, we would take a long time to make decisions because we would have to look at each choice individually and figure it out for itself. When you have an important decision (i.e. one that involves money) it's best to slow the process down and try to eliminate the effect of placebo and bias from the decision. That way you know you're basing your decision on something real, not just your mind telling you to hurry up and come to a conclusion. For everyday unimportant decisions, it's fine to go with the flow.


----------



## Redcarmoose (Dec 11, 2018)

bigshot said:


> I can guarantee it isn't the first. If you come up with a USB cable that has coloration, I would appreciate being able to borrow it for testing by the group. It would be interesting to find out exactly how it is altering the sound.
> 
> Placebo is a normal human trait. So is bias. If we didn't have those, we would take a long time to make decisions because we would have to look at each choice individually and figure it out for itself. When you have an important decision (i.e. one that involves money) it's best to slow the process down and try to eliminate the effect of placebo and bias from the decision. That way you know you're basing your decision on something real, not just your mind telling you to hurry up and come to a conclusion. For everyday unimportant decisions, it's fine to go with the flow.



I meant the first I have personally tried which sounded different in sighted tests. Maybe because it was more expensively priced?


----------



## bigshot

Did you pay for it?


----------



## Redcarmoose

bigshot said:


> Did you pay for it?



Yes.


----------



## bigshot

Why?


----------



## Redcarmoose

bigshot said:


> Why?



Because I rarely believe important stuff unless I try it for myself. Maybe you should try one too.

Have you ever done a blind test with an expensive USB?

Many of the chances I’ve taken have been surprising in audio. I basically only believe my own ears. Also I can’t get a system upgrade unless I spend another 8K, which I’m not doing.


----------



## GrussGott

bigshot said:


> There’s no reason to believe USB cables make an audible difference.



Except for the thousands of people who perceive a difference and the fact that nobody has ever proved they can't.

Although your certainty despite zero expertise in the field, and any proof otherwise is impressive!


----------



## PointyFox (Dec 11, 2018)

GrussGott said:


> Except for the thousands of people who perceive a difference and the fact that nobody has ever proved they can't.
> 
> Although your certainty despite zero expertise in the field, and any proof otherwise is impressive!



Proving you can't hear a difference doesn't prove anything since that particular person may not have the ability to perceive any differences if they exist. The proof would be someone out of these "thousands of people who perceive a difference" proving they actually can hear a difference; which would be astonishing since people haven't even been able to prove they can hear a difference between amplifiers (Richard Clark Amp Challenge) let alone a single digital connector.


----------



## bigshot

If there is anyone who has been able to discern a difference between USB cables, under controlled conditions I would appreciate their help to validate the fact through listening tests and measurements conducted by the Sound Science brain trust. If this is true, let's prove it. If it's a lie, why are we wasting our time talking about it?


----------



## bigshot

Redcarmoose said:


> I meant the first I have personally tried which sounded different in sighted tests. Maybe because it was more expensively priced?





Redcarmoose said:


> Because I rarely believe important stuff unless I try it for myself.



Did you think it wasn't actually important, or did you buy it because it was expensively priced? Did you really just buy it or have you had it for a while? You're acting like you are trying to prove something through your argument. Would you like to submit your cable to independent testing and find out the truth?


----------



## Redcarmoose (Dec 12, 2018)

Redcarmoose said:


> Because I rarely believe important stuff unless I try it for myself. Maybe you should try one too.
> 
> Have you ever done a blind test with an expensive USB?
> 
> Many of the chances I’ve taken have been surprising in audio. I basically only believe my own ears. Also I can’t get a system upgrade unless I spend another 8K, which I’m not doing.





bigshot said:


> Did you think it wasn't actually important, or did you buy it because it was expensively priced? Did you really just buy it or have you had it for a while? You're acting like you are trying to prove something through your argument. Would you like to submit your cable to independent testing and find out the truth?



I was told it could result in an important sound upgrade. And in sighted tests it does just that.

Again, this is a fairly simple process for myself. I would never give the cable out. Just going to test it myself. I’m not really interested in what others do, though I feel they should try a simple test themselves instead of just believing there is no difference.

I personally think when I’m done with my blind test, I figure there will be no difference between expensive  AQ USB cables or cheap ones. But......in case there is a true sound quality improvement, then that’s a win!



My history so far is pretty simple:

1) Get suggestions from others. Purchase cable. I have just purchased the cable new.

2) A blind test to hear for sonic improvements.

End of story.

But..........you never answered my questions. I will repeat the exact post at the top as quotation of myself; in case you missed my question.

“Have you ever done a test yourself to determine if expensive USB cables improve sound in your system? “


----------



## bigshot

I don't use USB cables for audio. I use HDMI. It was all wired by my home theater tech. He used Monoprice I think. I use USB and Firewire to connect my disk arrays to my media server. I use the cables that came with the arrays. Never noticed any skipping on serving high data rate video, so it must work fine. The only problem I've ever had with a digital cable is an extremely long run of HDMI from my AVR to my projector mounted up in the beams on the ceiling. The home theater guy bent the cable a little too much trying to work it around a corner and the cable shorted out. HDMI is delicate, especially over long runs. I doubt that more expensive cables would be more flexible. It's easy to tell if a cable is out of spec with HDMI because the handshaking at the beginning of the connection won't complete.

If you find that your cable is colored and doesn't sound like other USB cables, I hope you'll consider loaning it out to be tested. It would be useful to know what makes it sound different. I'm curious though... I seem to remember you used to argue that you didn't believe in the value of blind testing. What changed your mind?


----------



## castleofargh

Redcarmoose said:


> Because I rarely believe important stuff unless I try it for myself. Maybe you should try one too.
> 
> Have you ever done a blind test with an expensive USB?
> 
> Many of the chances I’ve taken have been surprising in audio. I basically only believe my own ears. Also I can’t get a system upgrade unless I another 8K, which I’m not doing.


 I'm really divided on this. on one hand I completely agree that actual(proper!) experiment is a really good way to know where we stand with our own gears and circumstances.
on the other hand, giving money to expensive(for what they are) audiophile products, to me that's like feeding the animal you're trying to get rid of.


----------



## GrussGott (Dec 13, 2018)

PointyFox said:


> Proving you can't hear a difference doesn't prove anything since that particular person may not have the ability to perceive any differences if they exist. *The proof would be someone* out of these "thousands of people who perceive a difference" *proving they actually can hear a difference*; which would be astonishing since people haven't even been able to prove they can hear a difference between amplifiers (Richard Clark Amp Challenge) let alone a single digital connector.



Well, first, to @castleofargh's point, we have no proof one way or another, and random experiments by some dude with some meters proves nothing, so hyperventilating about links and numbers is as valuable as me trying cables on my system: it's not scientific and proves absolutely nothing.

This is all the more true because we're not trying to find the Higgs Boson here - this is just encoding and decoding via software, thus whatever the truth is, *it's trivially easy to prove if one has the code.  *Thus the only reason nobody here knows, is because nobody here has the code.  Get it, and we'll know, don't have it and we won't.       / thread

*Specific to your point, *that's exactly what I suggested 1000 pages ago:

(1.) Start with a world-class system that's familiar to audiophiles, and someone who's very familiar with that system and who claims to hear cable differences.
(2.) Then have the doubters control the system, swap out the cables, and see if the person can identify the high quality cables.
(3.) Repeat a few times.

I suggested we test with Paul McGown, CEO of PS Audio, given he claims to hear differences, has access to some of the best audiophile equipment in the World, has 40 years of experience, and is willing to do the test in his Music Room 1.  He's even got Gus Skinas, who runs one of the best DSD mastering labs right on site.  Given Gus has recorded a large chunk of the SACDs out there, he probably has some listening experience too, and might have a few suggestions.

Unfortunately everyone here wussed out and won't do it because it'll likely prove them wrong.  Anyway, would be easy to do for anyone willing to schedule it with Paul and run the test.

Here's measurement nut Jon Atkinson of Stereophile in PS Audio's music room 1:







Here he's using music room 1 to test binaural recordings:


----------



## Brooko (Dec 14, 2018)

GrussGott said:


> Well, first, to @castleofargh's point, we have no proof one way or another, and random experiments by some dude with some meters proves nothing, so hyperventilating about links and numbers is as valuable as me trying cables on my system: it's not scientific and proves absolutely nothing.
> 
> This is all the more true because we're not trying to find the Higgs Boson here - this is just encoding and decoding via software, thus whatever the truth is, *it's trivially easy to prove if one has the code.  *Thus the only reason nobody here knows, is because nobody here has the code.  Get it, and we'll know, don't have it and we won't.       / thread
> 
> ...




Nope - you don't get to do this.

Onus on you - not on us.  Put up or shut up.


Objective real evidence:
http://archimago.blogspot.com/2013/04/measurements-usb-cables-for-dacs.html


More objective real evidence:
https://www.audiosciencereview.com/...s/do-usb-audio-cables-make-a-difference.1887/
Note that they also talk about audibility here, and the measurements confirm that any differences would be beyond the threshold of audibility unless packets were being dropped.


Further discussion about the tests in (1) above
http://archimago.blogspot.com/2013/06/musings-about-those-usb-cable-tests.html


Commentary - well worth reading - from an engineer - he talks cables in the section on Audiophile Digital Cables
https://medium.com/@skikirkwood/truth-lies-and-fraud-in-the-audiophile-world-a365e56c97c4


Commentary from Mark Waldrep - Studio owner, does this for a living, and in audio world his set-up is "mission critical"
http://www.realhd-audio.com/?p=5561
Most of the comments I’ve read around the web devolve into the same age-old argument about whether cables make a difference in the fidelity of your system or not. Intelligent people on both sides of the debate make their cases without any convincing anyone to change their mind. Believers will continue to believe while those that tend to the “show me data” end of the spectrum remain steadfast in their rejection of $1000 HDMI or USB cables. You all know where I stand on this issue. Don’t buy cables thinking they are going to improve the fidelity of your system. If you like the wonderful windings, the cool colors, the heavy connectors, or the status of a branded cable, then by all means spend the money…but don’t expect the sound to improve. There are plenty of other things you can do…at far less cost…that will affect your sound.

A functioning digital audio interface cable (AES-EBU, S/P DIF, SDIF, USB, or HDMI) cannot and should not alter the bit stream connecting a digital source component to a digital destination. All those “believers” who challenge this important fact are living in a dream world. Simply stating that hearing is believing doesn’t cut it. I know there are many individuals, reviewers, companies, consumers, and publications that profess otherwise but they all have a vested interest in perpetuating this myth…and others. Professional audio studios don’t use expensive cables or power cords so why should you?

*I can’t say that I’ve tested every permutation, format, cable, connector, or material but I did compare the data delivered by a $300 USB cable and a $5 USB and found that each successfully delivered exactly the same data. The audio from the different cables when the polarity of one was reversed completely and exactly nulled the other. The both accomplished their tasks with equal “fidelity”…as expected.*

Right - I've shown from multiple sources that in every instance, the USB cables in question make zero audible effect.

*So please - just deliver ONE - repeatable measurable difference using two cables which both meet the audio standard and that produce audible differences. Just one.*

And to reference your previous (pitiable) answers:

The measurements aren't anecdotes of amateurs - at least 3 of them are professionals in the industry
Its not conclusive, but in the absence of any contradictory measurable data in this thread, and the fact that no one has produced any (my internet search definitely didn't turn up any), it does point to a repeatable pattern
While this is not my field - it is for the people I've quoted - and please lay off the smarmy "deluding" comments. The only one doing it appears to be you. It's obvious, and it denigrates from the purpose of the thread. Please have some respect for the people actually looking for enlightenment
I have shown documented real evidence in the links. They are not guesses. They are not speculations. And if you want to call people like Mark Waldrep amateur or deluded - then I don't need to go any further.


----------



## Brooko

@castleofargh  - if he keeps this up, its the very nature of trolling.  I would expect you as a Moderator to close him down.  This isn't about closing down one side of the story either.  All he has to do is produce clear measurable evidence. This is Sound Science after all.


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## bigshot (Dec 14, 2018)

I'm with Brooko. He started out saying he had done a controlled listening test and proved to himself that he could identify USB cables consistently. Then when he was questioned about the test to attempt to verify it, and provided with examples of tests that showed the exact opposite of what he claimed, he changed course and started saying that tests don't prove anything. Now he's saying there are no tests at all. I don't believe a word that comes out of his mouth. I'm done with him.


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## JRG1990

Apparently now to determine whether theres an audible difference between usb cables we need code?.

Measuring thd, jitter etc isn't scientific enough, even though the tests are repeatable and 1 was done with nearly £3000 hardware that is even used by the manufacturer's of dacs.


----------



## Redcarmoose

castleofargh said:


> I'm really divided on this. on one hand I completely agree that actual(proper!) experiment is a really good way to know where we stand with our own gears and circumstances.
> on the other hand, giving money to expensive(for what they are) audiophile products, to me that's like feeding the animal you're trying to get rid of.



I am divided too in a sense as it doesn’t seem like something that would change the sound. But.......if you were to understand where I’m coming from it may make more sense. My system is a closed loop where the cable is not going from a computer but a DAP in a cradle which is simply a file sever for an external DAC/Amp. In this configuration it’s maybe like a computer or maybe not? But I have no other methods at this point to get any better sound unless I was to make a major upgrade. No other headphones, no other DAC or amplifier. No more cables or DAP file players.....there is nothing I could do other than AC filtering or AC regeneration. So getting an expensive USB has been suggested by others as a way to get improvement; with those folks owning the exact same equipment as I. 

So it’s maybe a slightly different application than simply using a computer, as the DAPs actually have a reputation of sounding slightly different than using a computer. Of course this is also an unprovable concept in itself.


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## SoundAndMotion (Dec 14, 2018)

Brooko said:


> @castleofargh  - if he keeps this up, its the very nature of trolling.  I would expect you as a Moderator to close him down.  This isn't about closing down one side of the story either.  All he has to do is produce clear measurable evidence. This is Sound Science after all.


Put some water in the Mr. Fusion so we can go Back to the Future:


SoundAndMotion said:


> Wow! That was a very classy PM. You have my respect. Given your explanation I have edited my post (although, yes, I know it lives on in your quote).


----------



## JRG1990

Redcarmoose said:


> I am divided too in a sense as it doesn’t seem like something that would change the sound. But.......if you were to understand where I’m coming from it may make more sense. My system is a closed loop where the cable is not going from a computer but a DAP in a cradle which is simply a file sever for an external DAC/Amp. In this configuration it’s maybe like a computer or maybe not? But I have no other methods at this point to get any better sound unless I was to make a major upgrade. No other headphones, no other DAC or amplifier. No more cables or DAP file players.....there is nothing I could do other than AC filtering or AC regeneration. So getting an expensive USB has been suggested by others as a way to get improvement; with those folks owning the exact same equipment as I.
> 
> So it’s maybe a slightly different application than simply using a computer, as the DAPs actually have a reputation of sounding slightly different than using a computer. Of course this is also an unprovable concept in itself.



The usb in a dap and pc are built to the same spec otherwise you wouldn't even be able to copy files to the dap. Like you say theres 0 evidence a dap or pc sound different over usb and a cable certainly won't change anything. Both should sound transparent.

The dap has the advantage in couple of ways being battery powered, having no fans, harddrives or other devices connected to it. But won't sound different to a noisey pc.


----------



## bigshot (Dec 14, 2018)

Redcarmoose said:


> I have no other methods at this point to get any better sound unless I was to make a major upgrade. No other headphones, no other DAC or amplifier. No more cables or DAP file players.....there is nothing I could do.



If your power is relatively clean and you aren't having problems, then you are done. Buying equipment at this point would be buying for buying's sake. Your best upgrade is music. Go out and buy a bunch of CDs in a genre you aren't familiar with and grow musically. Buying expensive wires is throwing money in a hole. If it ain't broke, don't fix it, as the old saying goes.

You have officially graduated from Head Fi. You no longer need better equipment. That is the goal we're all striving for and you have achieved it. Congratulations. I wish you well in the wider world of recorded music.

Soundandmotion, please don't back seat moderate. Castle does a very good job and these things are up to his discretion, not yours. Thanks.


----------



## SoundAndMotion

bigshot said:


> Soundandmotion, please don't back seat moderate. Castle does a very good job and these things are up to his discretion, not yours. Thanks.


Hmmm... You need to reread my post. I was complaining about @Brooko back seat moderating. I agree that Castle does a very good job and I respect his discretion. It seems that you and others who try to shoo people away are doing the back seat moderating.


----------



## taffy2207

Maybe he should moderate his attempted moderation of you trying to moderate. Sorted. You're welcome


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## bigshot (Dec 14, 2018)

Ha! Everyone should just make points and stop all the BS. I try to do that myself. Sometimes it seems like an endless vortex of argumentativeness. Im sick of it. I’ve written off several regular posters for that sort of nonsense. I’m happy to write off more.


----------



## Brooko

SoundAndMotion said:


> @GrussGott says he believes there is an audible difference. No one is obliged to prove him wrong, but he remains convinced and shares his view here. He suggests a way to test it that probably violates the rules for the rest of the forum, so it must be here in Sound Science. By replying to his post you validate it as worthy of rebuttal. Great; sounds like an internet debate.
> 
> But when you call for moderator action in a post you provoke 2 comments:
> 
> ...



I'll reply via PM - he is breaking the rules if he's trolling.  I should know - I used to moderate here.  And clearly you haven't read a lot of his posts.  I'd hazard a guess if we polled those on the forum - trolling yes/no, the response would be one-sided and overwhelming


----------



## SoundAndMotion

Brooko said:


> I'll reply via PM - he is breaking the rules if he's trolling.  I should know - I used to moderate here.  And clearly you haven't read a lot of his posts.  I'd hazard a guess if we polled those on the forum - trolling yes/no, the response would be one-sided and overwhelming


Wow! That was a very classy PM. You have my respect. Given your explanation I have edited my post (although, yes, I know it lives on in your quote).


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## SoundAndMotion (Dec 14, 2018)

...time for some music!


----------



## bigshot

No, I'm not talking about you. Sorry to be vague about it.


----------



## castleofargh

I believe we can all agree that I'm the best moderator in Sound Science(also usually the only one, but let's not mind the small details).
@GrussGott do you get a sense of what in your posts is perceived as trolling?
the reason we can't disprove all the claims of people hearing a difference is because pretty much none of those people are providing us with any relevant data. meaning first and foremost that we don't have to disprove anything because they only provided us with empty claims/impressions. we can reject them all without having to demonstrate anything. and that's the situation we're in. it would be wrong to assume that we cannot dismiss them because we lack data. the lack of data is the reason to dismiss those impressions.

but let's say we wish to engage anyway and help demonstrate or disprove something. let's say you try 2 cables and feel you're getting a difference, if I purchase the same brand of cables and same DAC you have, do a proper blind tests and detect nothing, will that prove beyond doubt that you're not actually hearing anything and that the cables make no difference? no it won't. in effect your situation might not be duplicable for me. even if I got your own 2 cables and your DAC to strongly reduce the potential variables, there could still be too many unknowns. from the computer, the environment, our respective listening skills, etc. and that means 2 things:
1/ what I would do is never going to be more than an anecdote.
2/ if anybody can show anything and provide any sort of evidence about your experience, it's probably you! and same thing for all those who wish their opinions to be taken as more than a sighted impression. but throwing more or less random hypotheses at us and hope we'll bite, that's not how you're going to demonstrate something. you think it's RFI, cool, show us it is. you think it's the super proprietary whatever from a cable seller, cool, show us measurements showing the significant improvement in fidelity. but just throwing ideas everywhere, that only makes more ideas you need to test, as you're the one allegedly getting clear differences and arguing that those hypotheses are worth something. that part will not change, you only increase your own burden(assuming that you wish to get to the end of this and aren't only here to troll).


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## GrussGott (Dec 15, 2018)

castleofargh said:


> @GrussGott do you get a sense of what in your posts is perceived as trolling?



Yes!

Because I'm reminding people their unscientifically-proven position is, in fact, only an opinion and that annoys them.  However, since this is the science thread, I'm holding them to the scientific standard:

If they're going to take a definitive position on the topic, they should scientifically prove that opinion (and miscellaneous amateur experiments do not equal scientific proof, otherwise Newton could've just eaten the apple and skipped the hassle of inventing a gravitation equation).  Anyway, @SoundAndMotion said it much more epically than I could.

Which brings me to providing some clarity (again) on my own opinion, given it's constantly mischaracterized:

*GG's Definitive Opinion on the topic of "Why do USB cables Make Such a Difference"*  <-- please reference or copy this if you wish to tell people what I think (this means you @bigshot )

*(1.) USB cables might not matter* as there's some evidence supporting that.

*(2.) USB cables might matter *as there's some evidence supporting that.

*(3.) Neither of these positions have been scientifically proven, thus nobody knows*

*(4.) Proving whether cables matter requires access to the firmware source code*, which has nothing to do with science, it's just analysis, so I'd question if this thread even belongs here

*(5.) A high quality listening test such as I've recommended won't prove anything,* but it might disprove an industry expert who believes he can tell the difference, and that *would be fun AND interesting.
*
In short, we cannot definitively answer this question due to inability to complete the analysis, not for any science reason.


----------



## Brooko

Please address the tests which have been done and show no measurable difference.  And stop with the "unscientifically-proven position".  I've given you measurements and opinions from people in the industry (ie expert opinions).

As to the "*USB cables might matter *as there's some evidence supporting that." - please provide the evidence.  So far all you have is anecdotal - no blind tests, and definitely nothing performed under rigorous testing conditions.  For it to mean something - it needs to be:
 - blind (the gold standard)
 - no deviations in anything except the cables
 - random generation of samples
 - repeatable
When you provide evidence of that, then we can actually get the cables mentioned into a laboratory and see if we can measure a difference.

Oh - and what is this gobble-de-gook  *(4.) Proving whether cables matter requires access to the firmware source code*,

More attempts to obfuscate and confuse?

Please show the evidence.


----------



## bfreedma

GrussGott said:


> Yes!
> 
> Because I'm reminding people their unscientifically-proven position is, in fact, only an opinion and that annoys them.  However, since this is the science thread, I'm holding them to the scientific standard:
> 
> ...




Have you not read any of the information in the links @Brooko keeps posting, or are you purposely ignoring them?  If you disagree with the findings, specify why.

Please provide the evidence supporting #2 that clears all of the hurdles you’ve “established” as requirements.

Point 4 is bunk.  There is no need to have access to the source code when the output of two cables can be captured and compared.  Either the data is identical or it isn’t.


----------



## GrussGott

Brooko said:


> Please address the tests which have been done and show no measurable difference.  And stop with the "unscientifically-proven position". * I've given you measurements and opinions from people in the industry (ie expert opinions).*



If you don't understand why that's not even a stitch toward scientifically proven, then maybe we need a new thread on what "scientifically proven" is.


----------



## GrussGott

bfreedma said:


> Point 4 is bunk.  There is no need to have access to the source code when the output of two cables can be captured and compared.  Either the data is identical or it isn’t.



yeah, that's a fundamental misunderstanding of the equipment and science so we're at a stopper.


----------



## Brooko

Posts reported - I suggest others do same.  Blatant trolling now.


----------



## bfreedma

GrussGott said:


> If you don't understand why that's not even a stitch toward scientifically proven, then maybe we need a new thread on what "scientifically proven" is.





GrussGott said:


> yeah, that's a fundamental misunderstanding of the equipment and science so we're at a stopper.



As usual, no specifics, just deflection.


----------



## GrussGott (Dec 15, 2018)

Brooko said:


> More attempts to obfuscate and confuse?



Yes, Brooko, because you're a big smartie hero and everyone who disagrees with your OPINION must very very bad man!

You might consider you have an overinflated sense of your expertise and ability to judge a definitive answer ... Might that be possible???

Naw, you've probably got everything figured out.

I mean, might as well assume that?

You couldn't be wrong.

everyone else is.


----------



## GrussGott

Brooko said:


> Posts reported - I suggest others do same.  Blatant trolling now.



That's funny, I reported your posts too!  Blatant insults, trolling, and impolite


----------



## GrussGott

bfreedma said:


> Have you not read any of the information in the links @Brooko keeps posting, or are you purposely ignoring them?  If you disagree with the findings, specify why.



Dude.  asked and answered like 1000 times (read back 80 pages).  It's not scientific proof.


----------



## StandsOnFeet

107 pages on _this _topic? The trolls have been eating well.


----------



## god-bluff

Yes hundreds of posts by just one person. I don't know where they find the time. The subject consumes them totally . What a  waste


----------



## gregorio

GrussGott said:


> yeah, that's a fundamental misunderstanding of the equipment and science so we're at a stopper.
> Dude.  asked and answered like 1000 times (read back 80 pages).  It's not scientific proof.



No, it the exact opposite. Although you are correct that "we're at a stopper" as clearly you are unable to recognise what is objective scientific evidence (and what isn't) or even realise the basic scientific principle of "burden of proof", even though it's actually posted as a headline in this sub-forum's home page!

G


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## GrussGott (Dec 15, 2018)

bfreedma said:


> As usual, no specifics, just deflection.



(1.) Scientifically proven means we have a predictive theory that proves _it's IMPOSSIBLE_ for USB cables to make a difference_ for all ears, for all equipment, for all environments_. We don't have that.  No links posted have ever shown that (and I'm pretty sure 1000 pages ago I posted those links; I also posted the often-used link to the 2011 USB.org letter which says USB cables don't matter, except when you actually read the letter it says everything I'm about to tell you, and posted previously.)

(2.) Because we're talking about the transmission medium of an encoded signal, we'd need to show that the signal BEFORE encoding is ALWAYS reproduced 100% by the receiver AFTER decoding - why?

(3.) This means we need to understand how the decoder works and deals with signal variance during transmission: can this results in errors, and if so how does the decoder deal with that, and if so can we hear it?

(4.) The USB audio spec doesn't provide for error correction, i.e., unlike a USB file transfer which can check for errors and re-ask for data, UAC doesn't re-ask, plus UAC also must account for timing (go back and read any of my posts with charts, graphs, tables, copies of the USB spec where all of this is explained)

(5.) If USB bulk transfers do check for errors and re-ask for the data .... are those errors 100% originating from the sender-only for all equipment in all environments, or might some of those errors happen during transmission?  And if some of those errors happen during transmission, that means the cables, and if UAC can't correct for errors, then cables might make a difference through shielding or other factors.  We'd need to understand all of that before we could begin to know what to measure.  Thus we need to understand how the receiver code (e.g., XMOS firmware) deals with signal variance.

And if you actually are curious rather than defending a biased position you have no intention of changing, please know i'm not saying cables DO matter, i'm saying we don't know for certain they don't, and they appear to work for me, but I could be mistaken.


----------



## GrussGott

gregorio said:


> you are unable to recognise what is objective scientific evidence



And you are unable to recognize that scientific evidence on some equipment, in some environment, analyzed by a few people, DOES NOT EQUAL scientific proof.

If one was extremely biased, they'd look for any evidence their bias was correct, find it, and stop.

Sorry Greg, limited testing of limited equipment by a few people does not equal proof - and I'm sorry for everyone frustrated by that fact.

but it is a fact.

Nothing proven, so the adventure continues!


----------



## gregorio

GrussGott said:


> (1.) Scientifically proven means we have a predictive theory that proves _it's IMPOSSIBLE_ for USB cables to make a difference_ for all ears, for all equipment, for all environments_.
> (2.) Because we're talking about the transmission medium of an encoded signal, we'd need to show that the signal BEFORE encoding is ALWAYS reproduced 100% by the receiver AFTER decoding - why?
> (3.) This means we need to understand how the decoder works and deals with signal variance during transmission: can this results in errors, and if so how does the decoder deal with that, and if so can we hear it?
> (4.) The USB audio spec doesn't provide for error correction, i.e., unlike a USB file transfer which can check for errors and re-ask for data, UAC doesn't re-ask, plus UAC also must account for timing (go back and read any of my posts with charts, graphs, tables, copies of the USB spec where all of this is explained)
> ...



1. No it doesn't. What we do have though is overwhelming reliable evidence that differences are way below audibility. The *burden of proof* is on you to provide some reliable counter evidence and you haven't provided a single shred. You cannot just keep ignoring the requirements of science and then cry "you're not being scientific". Read the "burden of proof" on the home page of this forum and STOP arguing a fallacy!!
2. No we don't. We talking about the transmission of digital data, we therefore need to show that the digital data exiting the cable is identical to the digital data entering the cable, which is easy to do and has been done countless times. Also done numerous times is actually comparing the output of the DAC, which demonstrates difference many times below audibility.
3. It should not result in errors and extremely rarely ever does. If it does, the internal error correction of the DAC should handle it, if that error correction is overwhelmed then we can hear it (as a burst of static).
4. Any cheap decent DAC can handle timing well beyond the ability of any human to detect.
5. What errors?
5b. We do understand all of that and have done for decades. And anyway, we don't need to know what to measure, we can just perform a null test, which measures EVERYTHING in the signal.

You've been told all this before and choose to ignore it. That's your prerogative of course but it's not your prerogative to define science to suit your belief and repeat your belief endlessly when it's so clearly contradicted by the science (at least in this sub-forum)!

G


----------



## GrussGott (Dec 15, 2018)

gregorio said:


> The *burden of proof* is on you



That's not how science works Greg, and this is the science thread.

In this case, I'm saying we have no definitive answer one way or another, and you (and others) are saying we do; yes you have some evidence, but that's not proof, that's just speculation based on limited empirical observations.  not proof.  speculation.  Thus if you're claiming we have a definitive answer, you have to prove it and you haven't thus no definitive answer.

And, BTW, your opinion is totally fine _if you disclaimed  that (a.) you're not a digital signals expert, (b.) therefore while you have a strong opinion based on what you've seen, you don't really know._

But you don't do that Greg, so I'm pointing out that you don't just in case someone might take your (and many others here) unproven certainty as a fact, and then pass along that misinformation to others, thus spiraling out misunderstandings.

I don't have to prove a thing, because I'm not taking a position one way or another, but you are, so you need to prove it or disclaim it's just an opinion.  QED.


----------



## bigshot

What a waste of words. This is what it looks like when you have no argument and you wouldn't even be able to put across an argument if you did. I second Brooko's motion on how to handle this.


----------



## GrussGott

bigshot said:


> What a waste of words. This is what it looks like when you have no argument and you wouldn't even be able to put across an argument if you did. I second Brooko's motion on how to handle this.



I agree, I'm not sure why people keep claiming they have a definitive answer for all ears, equipment, and environments when all they have is a few limited experiments.

Occasionally you and I agree.


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