# Don't get why "Audiophile" USB Cable would improve sound quality



## throzen0303

I have seen USB cable price from $1 to $550+ each,
  I do understand a $10 cable is going to be build better than a
  cheap $1 cable, but, isn't USB, digital in general just transfering 01 signals?
  If it is, isn't it a Yes/No situation? Yes meaning the signal made it through, job done,
  No being the signal didn't go through(rarely happens), How would a silver wire USB cable
  improve the sound quality? Is this just a marketing thing? We see tons of CAT.6 cable,
  the cheaper once deliver the same speed as the more expensive once. at the same length.
  I don't see any audio dacs using USB 3.0 at this moment,
  taking the advantage of the faster speed there for less change if signal loss if any.
  Please do advice. Thank you.
   
  I am asking this question because I am going to order a NFB12,
  the standard cable that comes with it on the picture are....standard,
  just not sure about the advantage people are talking about with "high-end"
  USB cable.


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## JxK

http://sound.westhost.com/cables.htm
   
  Read that. It explains in relatively simple language (though on occasion it does go into some depth) why cables do not do anything to change the sound quality. Read up, and see why anyone with any background in physics or electrical engineering can't help but be disgusted by the cable scam.


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## Nuwidol

I always wander this too.
   
  Check this cable out...


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## Mambosenior

I have my picnic basket ready, a good cigar, and a front-row seat for the upcoming donnybrook. Let the USBullets fly!
   
  (The first combatant that mentions “1s and 0s” has to sit in the penalty box for a spell and listen to Schönberg through Bose headphones.)
   
  Oh well, I must venture that I use a Locus Design “Polstar” USB cable. Do I hear the difference between it and an the grey El Cheapo? Well, I’ve told myself that the black background through the LD is blacker than black and that mantra has helped to keep me in the dark about the cable issue.


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## throzen0303

I just don't get why people pay over $10 for a USB cable, I don't think gold plating plug will do anything too,
  since the pins of USB connector are inside.
  Pretty insane by those marketing people.


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## bcasey25raptor

Quote: 





throzen0303 said:


> I just don't get why people pay over $10 for a USB cable, I don't think gold plating plug will do anything too,
> since the pins of USB connector are inside.
> Pretty insane by those marketing people.


 


  I agree, I would have trouble paying more then $10 myself. It is just ridiculously stupid that people think it makes a difference. I feel the same about burn in. I noticed no change in any of my headphones.


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## throzen0303

Quote: 





bcasey25raptor said:


> I agree, I would have trouble paying more then $10 myself. It is just ridiculously stupid that people think it makes a difference. I feel the same about burn in. I noticed no change in any of my headphones.


 

  I do notice change with IEMs and Tube amp(no experience with solid state), not much with headphones


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## throzen0303

mainly BA based IEM i see change


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## Roller

I bought a shielded cable with gold connectors and ferrite chokes on both ends for a single purpose, to eliminate any chance of EMI, as well as eliminating any crackles or popping that came up once in a while with the stock cable of my DAC. It worked perfectly because that was the job it was meant to do, and it just did it, simple. BTW, the cable went for $15.
   
  I have better things to spend money, such as better amps, DACs, headphones, etc. But to each their own


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## travisg

Locus Design Axis USB owner. Trust me there is a difference.


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## Currawong

Well, there is the logic that if your DAC is sensitive enough that changing the USB cable makes an audible (or even measurable) difference to the sound, then you should buy a better DAC.  
   
  However, my latest toy from Audiophilleo comes with a Wireworld UltraViolet cable. I do like how, internally, it separates out the power and data wiring.  I shall be building my own separate PSU, possibly using batteries, for the power side, however. A solution that actually fixes the problem is always going to be superior to a fancy cable, whether or not the cable has any useful effect.


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## WrxSTI

It wouldn't, and it doesn't.
   
  It just looks better.


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## travisg

I use my ears not my eyes


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## throzen0303

travisg said:


> I use my ears not my eyes




Can you describe the difference for the USB cable? I understand why a good analog cable is needed, and I do hear the difference. But digital, not so. I saw a $3400 USB cable, for that, just get a better DAC or Headphones


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## travisg

The difference is in the sound stage. Clearly to my ears its way more open than a 10.00 cable. As far as the 3400.00 Locus Cynosure cable I would say that its for people who tend to have at least 50.000 in their equipment and feel like they may need to squeek out every advantage they can. Once you get up to 100,000 any upgrade at all I would guess would be a minimum of 5,000 dollars.I have over 30,000 dollars in audio gear and therefore feel like 550.00 for a cable that obviously makes a difference to my ears is a fair price to pay.Also yea it looks cool.


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## throzen0303

hmmm, what do you think about the Fiio e5 0.0....why are you using that if....


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## Shahrose

Quote: 





travisg said:


> The difference is in the sound stage. Clearly to my ears its way more open than a 10.00 cable. As far as the 3400.00 Locus Cynosure cable I would say that its for people who tend to have at least 50.000 in their equipment and feel like they may need to squeek out every advantage they can. Once you get up to 100,000 any upgrade at all I would guess would be a minimum of 5,000 dollars.I have over 30,000 dollars in audio gear and therefore feel like 550.00 for a cable that obviously makes a difference to my ears is a fair price to pay.Also yea it looks cool.


 


  I agree.
   
  I've also heard differences from USB cables.


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## travisg

Old profile


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## travisg

Ok everybody you got me, I bought the cable just because I can. It sounds no better than a free cable. HAPPY? Just like my old FIIO E5 sounds better than my Isabellina. And my Ipod ear buds sound way better than my JH16's


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## throzen0303

travisg said:


> Ok everybody you got me, I bought the cable just because I can. It sounds no better than a free cable. HAPPY? Just like my old FIIO E5 sounds better than my Isabellina. And my Ipod ear buds sound way better than my JH16's




Don't have to be mad, but I haven't experienced your setup so I can't give a definitive answer, but they are just saying could you tell the difference on a blind test


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## ABXG

USB cables have a digital and an analog component to them. The digital component transmits the actual audio data while the analog component provides power. A "better" USB cable will provide some filtering along with shielding the data and power lines in order to provide the DAC with purer power.
   
  I notice a difference between my Kimber cable and the cheap USB cables I had lying around, so for me the extra cash was worth it.


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## uelover

I second the idea that USB cable makes a difference. It is not all about 1 and 0 because USB audio has got no error correction built within it and waveforms can get distorted when it reaches the DAC, resulting in misinterpretation on the DAC end.
   
   People always say that if you have the money to get good cables, you should upgrade your audio equipments. That is not true.
   
  For example, upgrading to a 'better' DAC from my current one will cost me a lot more money. Getting a 'good' USB to SPDIF converters cost a bomb too.
   
  So, I got a WW Starlight USB cable and it improves the sound by much more than what I was expecting.
   
   
  It depends on which spectrum you are at. If you are using FiiO DAC, I will not recommend getting an expensive USB cable even if it improves the sound because you will be able to get a better DAC with the cost you are paying for the cables. But if you are somewhere higher, you may want to consider upgrading your USB cable as an alternative.


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## WrxSTI

Quote: 





abxg said:


> USB cables have a digital and an analog component to them. The digital component transmits the actual audio data while the analog component provides power. A "better" USB cable will provide some filtering along with shielding the data and power lines in order to provide the DAC with purer power.
> 
> I notice a difference between my Kimber cable and the cheap USB cables I had lying around, so for me the extra cash was worth it.


 


  But most of these expensive DAC's have their own power supplies anyway, do they not?


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## kn19h7

...so how many here actually did study on specifications and logic of Universal Serial Bus and digital transfer before stating its just bit-perfect 0s and 1s that cable can't make any differences? Me too lazy to go through all those so any clarification would be appreciated. I think just talk about clocking issue and error handling should be enough, lets aside the power cord issue first..


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## Willakan

The documentation for the USB audio transfer standard shows that the standard does not feature error correction, that is true. But again, people seem to have some very strange ideas about digital audio. If your cable has so much noise that it renders a part of a square wave unreadable, it's probably a 99p one off Ebay. If somehow data is corrupted, the result isn't going to be "subtle reductions in sound stage" or a "harsh treble" or anything like that - more like nasty noises.
   
  As for jitter, the USB interface is, as usually implemented, inherently more jittery due to the need to reclock the audio - but even then, this quite unlikely to have any audible effect on the sound and has prettymuch nothing to do with the cable. 
   
   
  The essential problem with many of the attributes given to these USB cables is that they don't make any sense. Let's assume that, against all odds, my reasonably priced USB cable is somehow degrading the audio signal. Firstly, for the differences people claim to hear to be occurring, it couldn't be just the odd unreadable bit - there would have to be some constant sort of degradation. The kind of subtle, constant differences that people claim really don't make any sense, as using my magic wand to corrupt large numbers of bits would not result in something playable properly at the other end.
   
  Take an HDMI cable as a great example. If I plug in a defective HDMI cable that is not standards compliant into my TV between my PS3, I might get noise, or white lines, or a whole array of visible artifacts onscreen. I do not get "subtle dulling of the complementary midtones" or a "reduction in the vibrancy of the most extreme hues."
   
  Let's face it, the arguments as to why some analogue cables supposedly sound better make vanishingly small amounts of sense, let alone those pertaining to digital cables.
   
  On another note, I sense a move to the Sound Science forum may be imminent.


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## uelover

Hey Willakan,
   
  All USB and HDMI cables, no matter how cheap they are, are able to carry and transmit most information accurately from one point to another. If not, they will not be sold in the market in the first place because they are outright defective.
   
  However, saying that a high grade USB cables could transmit signal more accurately than stock cable does not imply that stock cables are junk. For example in the case of HDMI cable, a good HDMI cable will be able to show the sky in a more vibrant and vivid blue than a stock HDMI cable. It is not that the entire sky disappear, but the preservation of the data at the D/A end is better.
   
  There are three types of USB cables:
  1) Standard stock cable which most of us use
  2) Snake oil cables (marketing gimmicks with not much difference from standard cables)
  3) Higher grade cables.
   
  To save myself money from getting good cables, I bought my current DAC for the reason that it has excellent jitter rejection and USB implementation. I bought Digital Interface in good faith that asynchronous USB transfer eliminate the need for good cables. Thing is, USB cable still make a reasonable impact on my sound - quieter, cleaner, more accurate.
   
  This topic has been brought up and debated so many times that repeating the debate all over again is useless. If you have the opportunity, listen to Furutech GT or Wireworld USB cable. I have heard them and they do impact the sound. I am not so sure if the same holds true for Kimber/Monster USB cable.


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## Willakan

And that's where we'll agree to disagree - IMO the HDMI cable will not make a difference and if it is standards compliant will never make a difference, because it's impossible. But that's probably not a discussion for the cable forum, and I'm certainly not going to buy them myself on the offchance conventional science ceases to apply. 
	

	
	
		
		

		
			




   
  EDIT: Comparison may not be entirely fair, as I'm pretty sure the HDMI standard has some provision for error correction, but the basic idea still stands.


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## uelover

Haha yeah we will leave it to other people to debate and save our breath =)
   
  Anyway Willakan, if you ever get an opportunity to listen to a comparison between a good and standard USB cable, please don't forgo that opportunity but instead make use of it to prove to yourself that USB cable will not make a difference.
   
  I came from that path myself


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## john mcguirk

I can't say that a high-end USB cable will make an audible difference, but your understanding of how binary numbers are "moved" around in a circuit is very misconstrued. But it's not your fault, popular culture of the last 20 years has led you to believe what you do.
   
  There are not literally zeroes and ones flying around inside your electronic devices, and it's not true that the ones, as you call them, "make it through" and the zeroes "don't (rarely happens)." If zeroes never "made it through" then you'd just have ones "making it through" all the time.
   
  What really happens is that our idea of binary numbers are simply an abstraction, or representation, of voltage levels within a circuit. Yes, at a higher level a programmer really can interact with binary numbers (but few do). The circuit actually has three states -- no voltage being passed through, a "low" level voltage (we can think of this as being represented by 0) and a "high" level voltage being passed through (our 1). It is a combination of low- and high-level voltages being passed and subsequently grouped together in an ordered manner millions or billions a time a second which allows us to enjoy digital circuitry. If we just had a single voltage level, your notion that only ones "make it through", then we would have two states (off and on) which is useless for any sort of decision making.


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## uelover

Quote: 





john mcguirk said:


> I can't say that a high-end USB cable will make an audible difference, but your understanding of how binary numbers are "moved" around in a circuit is very misconstrued. But it's not your fault, popular culture of the last 20 years has led you to believe what you do.
> 
> There are not literally zeroes and ones flying around inside your electronic devices, and it's not true that the ones, as you call them, "make it through" and the zeroes "don't (rarely happens)." If zeroes never "made it through" then you'd just have ones "making it through" all the time.
> 
> What really happens is that our idea of binary numbers are simply an abstraction, or representation, of voltage levels within a circuit. Yes, at a higher level a programmer really can interact with binary numbers (but few do). The circuit actually has three states -- no voltage being passed through, a "low" level voltage (we can think of this as being represented by 0) and a "high" level voltage being passed through (our 1). It is a combination of low- and high-level voltages being passed and subsequently grouped together in an ordered manner millions or billions a time a second which allows us to enjoy digital circuitry. If we just had a single voltage level, your notion that only ones "make it through", then we would have two states (off and on) which is useless for any sort of decision making.


 

  
  Hey John,
   
  Let's just leave this to computer audio forum.
   
  USB audio is not as simple as what you would like to think.


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## john mcguirk

Quote: 





uelover said:


> Hey John,
> 
> Let's just leave this to computer audio forum.
> 
> USB audio is not as simple as what you would like to think.


 


  Not too sure where you came up with that -- I never said a word about USB audio and I am not foolish enough to "like to think" that it's simple at all. But you are right to keep the tech-talk to that forum.


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## throzen0303

If cable companies claim that their USB cable can be better than others, what is it based on?
  What factor makes a USB cable good?
   
  Does gold-plated connector help? Most HDMI cable are gold plated, including the one I have right now 13.8G/s speed.
  I am not sure why gold plating USB cable would help tho, most jack for USB are not even gold plated, and the connecter for USB
  are the pins inside, which are already gold plated(or is it just naked copper??) So gold plating the "housing" for the connector should not help.
   
  A higher gauge wire? I was someone talking about power transfer with a better made higher gauge power cable inside the USB,
  but my DAC comes with a good power supply already, why do i need that?
   
  Shielding should help?
   
  What else?


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## Shahrose

A few variables that I've seen altered among aftermarket cables: conductor material and gauge, shielding (different types), length of wire, separation/shielding of power/data lines, connector quality including plating (but the latter's really for protection against oxidation).


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## pd1516

It seems to me, in order for a USB cable to be able to corrupt audio, wouldn't it corrupt data in the same manner? Like the waveform would be corrupted, wouldn't the text file that I transferred through this "inferior" USB cable have mistakes and incorrect characters?
   
  I would imagine that just like my data is never corrupted when transferring through any USB cable, I wouldn't believe audio could be altered either.


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## Shahrose

Quote: 





pd1516 said:


> It seems to me, in order for a USB cable to be able to corrupt audio, wouldn't it corrupt data in the same manner? Like the waveform would be corrupted, wouldn't the text file that I transferred through this "inferior" USB cable have mistakes and incorrect characters?
> 
> I would imagine that just like my data is never corrupted when transferring through any USB cable, I wouldn't believe audio could be altered either.


 


  Not the same, there are different tolerances for both. I can't answer your question in detail, but I know someone else on here can. (I've inquired the same before).


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## travisg

you need to buy cables that are relative to your other equipment. dont buy a 600.00 cable to put on a 100.00 dac. but if you spend 10,000.00 i think you might want to try and get all the advantages of a better cable even if only slightly


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## throzen0303

I just ordered a NFB-12 for my HD600 (tight budget >.>" at $200, seems to be the best DAC+AMP out there),
  What can I upgrade to make the sound for my HD600 better,
  I got a custom Mogami 24awg*4 + Furutech 1/4 Plug for it, which improved the sound alot,
  my current setup is Creative sound blaster 5.1 USB(using as a DAC), to a Bravo Audio V1 6922 Tube amp(cheap stuff)


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## sridhar3

Quote:


throzen0303 said:


> I just ordered a NFB-12 for my HD600 (tight budget >.>" at $200, seems to be the best DAC+AMP out there),


 

 Good choice.  Do they have units in stock?  Recently they were having issues with delivery due to high demand.


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## DaBomb77766

Seriously, digital is digital.  It either gets there or it doesn't - meaning that if something doesn't "get there" you'll most likely be hearing things like pauses in the sound and random static that wasn't there before.  But it's impossible for it to actually change the "signature" of the sound.  Digital just doesn't work that way.  I mean seriously, if low quality transfer cables are enough for big data centers to use for backup, it sure as hell is good enough to use for audio.  Computers and audio files store information and move it around at speeds that are simply unimaginable to humans.  If one, two, even a few hundred bits get corrupted in transit it will be physically impossible for any human to tell the difference.  If the bitrate of the stream is, say, 1.4Mbps, that's 1.4 million bits per second.  Approximately 1,400,000 bits every second.  Really, I doubt that any amount of "corruption" to this would be noticeable, especially given that we can transfer data at much higher rates with even just USB 2.0.
   
  It just seems that people here often don't understand the simple concept of digital.  People think in terms of "analog," it's hard to get accustomed to the concept of "digital."  They're two completely different things that should not be thought as being the same.


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## Prog Rock Man

The digital signal is in analogue waveform, maybe that is why preople mix the two. Otherwise I agree, the signal either gets there or it does not.
   
  No one has shown how an analogue signal can make bass deeper or improve clarity, let alone how a simple on/off, 1 or 0 digital signal can do so.  Many cable makers have come up with their own reasoning, but since different cable construction methods can apparently all result in improvements to sound quality, straight away there is dubiety to those claims. There is too much puffery in cable maker claims and not enough real evidence.


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## justanut

I raised the same question in the CLAS forum actually.
   
  How many of you use rare metal USB cables for your connections to your external backup drives, to your iPhone etc.? We're talking about just 16bit (ok some 24bit) data being transferred over at most a couple of feet? If normal cables can't do the job, I'd be concerned when I'm copying my music files into my DAP.
  I wonder if the recording studios use audiophile grade cables hmmm?
   
  I don't know about blind tests. But I know that when I show my friend a cable that's supposedly 10x more expensive than another "cheaper" cable, they ALWAYS end up finding that it sounds better despite them being the SAME. 
   
  Anyway, if you've got the money and it makes you feel that your music's better, why not? I think my swarovski covered, gold plated iPhone sounds better than the normal one


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## 00940

Oh guys, it's been discussed to death already...
   
  http://www.head-fi.org/forum/thread/546191/usb-cable-supposedly-improving-dac-sound-quality-how-can-i-take-other-posts-seriously-after-that
  http://www.head-fi.org/forum/thread/417785/yes-virgina-there-is-a-difference-in-usb-cables
   
  Quote: 





dabomb77766 said:


> Seriously, digital is digital.  It either gets there or it doesn't - meaning that if something doesn't "get there" you'll most likely be hearing things like pauses in the sound and random static that wasn't there before.  But it's impossible for it to actually change the "signature" of the sound.  Digital just doesn't work that way.  I mean seriously, if low quality transfer cables are enough for big data centers to use for backup, it sure as hell is good enough to use for audio.


 
   
   
  You too should really update your knowledge of what digital is. There are various digital protocols, which can be very different in implementation and weaknesses. The USB protocol to transfer data is not the same as the USB protocols used to transfer audio. You cannot compare a time insensitive flow with error detection and correction (usb data transfer) with a time sensitive flow with no error correction (usb audio). In common USB audio modes, a subtle degradation of the signal, not resulting in drop out but low level distortions at the final analog output, is perfectly possible in theory (and is routinely measured). Such degradation can mostly be traced to interface jitter. Furthermore, a USB receiver chip is pretty much a mixed-signal IC, in which interaction in between analog components (such as PLLs) and power supply noise is susceptible to affect the digital output precision.
   
  This said, one can make the case that in most decent implementations the jitter is too low to be heard and that any decent USB cable will neither contribute significantly to jitter nor allow power supply lines and data lines to interfere in a significant fashion. One could also say that as long as cable makers do not provide figures showing concrete improvements by using their cables, either in terms of jitter or in terms of interferences in between data and power lines, they are not to be taken seriously. I would agree with such positions.
   
  However, the "digital is either perfect or corrupted" motto is just plain crap.


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## Prog Rock Man

In terms of what the actual cable does, digital is an anlogue waveform of ons and offs or 1s and 0s, with a timing signal. That is it. The cable either transmits the signal of it does not. 00940, you are adding in the rest of the digital chain to a debate about the role of the cable. That is a red herring as the cable does not know or influence or anything the protocol, errors or whatever of the transmission of the digital signal, so long as it is made to standard and is not faulty. If it does affect protocols etc it is broken or badly made. So the digital is perfect or corrupted motto is not crap, when discussing the effect (or lack of) of cables.
   
  Some cable makers have tried to show that their cable is better at transmitting that signal than others and have then insinuated that such will improve sound quality. But there is no real evidence for that.


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## 00940

Did you even read the part when I said that the effect of a decently built cable is likely insignificant ?
   
  Still, as the recovery of the timing signal in some USB audio protocols is dependant on the shape of the analog waveform and considering how the geometry and physical properties of a cable can have an effect on such analog shape (and thus on interface jitter), you need to understand the whole chain to understand the possible effects of the cable. For data transfer, the analog signal can get very distorted before we get in trouble. For some USB audio protocols (not for asynchronous though), the standard required for proper operation is higher. In order to dismiss the effect of the cable, you actually need to know the protocol and the whole chain requirements.
   
  And btw, that's a dual purpose cable (power and data) and not a pure digital one.


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## Prog Rock Man

If a cable (are there any on sale?) distorts the waveform such that it cannot recover the timing signal, then surely it would stop working rather than affect sound quality?
   
  When I say stop working I mean even if it just for a part of a second and it introduces a crackle or other sound that is not part of the music. Not just if the signal comes to a complete halt.


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## 00940

Quote:


prog rock man said:


> If a cable (are there any on sale?) distorts the waveform such that it cannot recover the timing signal, then surely it would stop working rather than affect sound quality?
> 
> When I say stop working I mean even if it just for a part of a second and it introduces a crackle or other sound that is not part of the music. Not just if the signal comes to a complete halt.


 

 It doesn't work that way. The signal timing is recovered from the edges of the packets. If the edge of the packet isn't square enough (something a cable could potentially influence), you introduce incertainty in the recovered clock, but it's not like you don't have a clock, you just have a jittery one. The protocol is sufficiently robust to work within such incertainty and to reduce it to a certain extent (that's the job of a PLL). However, those variations in the time domain will translate as distortions at the analog output (not as crackle or pop). The math for that is in some papers I've posted in the other threads (about spdif but the reasonning is the same). That's why some usb cables with big ferrites are fine for data transfers but might be problematic for usb audio transfer, as they "round"  the edges of the packets.
   
  Still, my point of view is that interface jitter introduced by a short, decent cable is no big deal. I myself use a cable grabbed from an old HP printer.


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## Prog Rock Man

I understand about the clock part of the signal and the issue of jitter.
   
  But jitter is another possible red herring as it has yet to be shown how jitter affects sound quality, it is just assumed it does. If there is a case where jitter is so high it does affect the sound and that level of jitter is down to the cable, I would argue the cable is faulty. I do not think DAC/cable makers are at a position yet to be able to say for certain that jitter reduction, particularly where with well made kit it is so low anyway, is needed to improve sound quality.
   
  Irrespectively, this is a discussion about USB cables and their supposed affect on sound. Is there evidence that a USB cable can introduce jitter, or is not a problem between the source and receiver? So the cable has no effect.


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## throzen0303

sridhar3 said:


> Quote:
> 
> Good choice.  Do they have units in stock?  Recently they were having issues with delivery due to high demand.




No they don't acutally, mine is going to be shipped by June 5th, after they build it and do the burn in testing to insure the quality.


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## throzen0303

sridhar3 said:


> Quote:
> 
> Good choice.  Do they have units in stock?  Recently they were having issues with delivery due to high demand.




No they don't acutally, mine is going to be shipped by June 5th, after they build it and do the burn in testing to insure the quality.


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## Icenine2

I don't get why either but it does sound better.  I've got the Cardas Clear USB.   Cost me about $100.  All the $$$ I've spent $100 isn't going to kill me.  Looks better if I peek in the back too!


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## uelover

Quote: 





icenine2 said:


> I don't get why either but it does sound better.  I've got the Cardas Clear USB.   Cost me about $100.  All the $$$ I've spent $100 isn't going to kill me.  Looks better if I peek in the back too!


 

 Nice to see someone crawling out of the mystical audio science cocoon and uses their ears instead =)


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## 00940

Quote: 





prog rock man said:


> I understand about the clock part of the signal and the issue of jitter.
> 
> But jitter is another possible red herring as it has yet to be shown how jitter affects sound quality, it is just assumed it does. If there is a case where jitter is so high it does affect the sound and that level of jitter is down to the cable, I would argue the cable is faulty. I do not think DAC/cable makers are at a position yet to be able to say for certain that jitter reduction, particularly where with well made kit it is so low anyway, is needed to improve sound quality.
> 
> Irrespectively, this is a discussion about USB cables and their supposed affect on sound. Is there evidence that a USB cable can introduce jitter, or is not a problem between the source and receiver? So the cable has no effect.


 
   
  Well, it is perfectly demonstrated "how" jitter introduces distortion. The problem is more "how much" jitter affects sound quality audibly. Go read my very first post again for my position on that wrt usb cables.
   
  And there seems to be measured evidence that USB cable can increase the level of jitter. Check if you can get your hands on the January issue of Hifi news for the article by Paul Miller (I can't sadly); from what I gathered in various places on the web, he shows differences in between various cables jitter measurements and at least one "audiophile" usb cable measuring worse than a stock cable.
   
  In an earlier article (december 2010, which I've got), he shows how jitter goes from 300ps to 3ns depending on whether or not the power supply of his laptop is attached to the laptop or not. I doubt though that cables would have such drastic effect but it goes to show how the USB audio protocols is far of being without problems.


----------



## Shahrose

Quote: 





uelover said:


> Nice to see someone crawling out of the mystical audio science cocoon and uses their ears instead =)


 

 Yea, for an audio forum we have an awful lot of people who refuse to use their ears. Everyone who's heard my system (even my non-audiophile friends) have been surprised when I told them that there are still Head-Fi members who don't believe in cable differences. To them, it was that obvious, and from a short audition too (and without me saying anything about the topic before hand).


----------



## uelover

Quote: 





shahrose said:


> Yea, for an audio forum we have an awful lot of people who refuse to use their ears. Everyone who's heard my system (even my non-audiophile friends) have been surprised when I told them that there are still Head-Fi members who don't believe in cable differences. To them, it was that obvious, and from a short audition too (and without me saying anything about the topic before hand).


 


  I think for most, analogue cable differences are acceptable but digital cable differences (coaxial, toslink, usb, hdmi) are unacceptable for almost 99% of the population here.


----------



## Shahrose

Quote: 





uelover said:


> I think for most, analogue cable differences are acceptable but digital cable differences (coaxial, toslink, usb, hdmi) are unacceptable for almost 99% of the population here.


 


  I will admit that digital cable differences were smaller than analog (IME). I've tried both USB and coaxial.


----------



## tmars78

Quote: 





uelover said:


> Nice to see someone crawling out of the mystical audio science cocoon and uses their ears instead =)


 

 Technically, you aren't using your ears. You are also using your eyes, and preconceived notions of what you should hear. If you know what cable you are using, then you are not using just your ears. I would bet that if you used JUST your ears, all of the "differences" you claim to hear, would go away.


----------



## uelover

Quote: 





tmars78 said:


> Technically, you aren't using your ears. You are also using your eyes, and preconceived notions of what you should hear. If you know what cable you are using, then you are not using just your ears. I would bet that if you used JUST your ears, all of the "differences" you claim to hear, would go away.


 
   
  tmars78. You need not tell me this.
   
  This is the typical reply one will get from those who do not believe digital cables will make any difference. Many have told many others this and a search in this forum, or any other, will reveal this statement you have just made.
   
  I have rejected many branded expensive cables (silver or crystal or whatever) for simple, cheap and well-built copper cable because they just sounded better. Price, brands, marketing gimmicks will trick many people. No doubt about that. Also, I will have to agree that there are too many snake oil cables out there costing a bomb and yet does nothing to improve the sound. People who fell for these tricks will be convicted that digital cables are all but a hoax. But, there are cheaper yet good digital cable that will improve the sound.
   
  So far those who argued for the case of no-difference in digital cables do so in the name of science and have not heard for themselves.
  Those who argued for the case of difference in digital cables have actually own/heard of it themselves.
   
  Placebo effect? Preconceived prejudice on cheap cables?
   
  I am not sure if results from a short blind ABX test can be conclusive, especially when the source and the acoustic environment is unfamiliar to someone. Having the cables plugged into your system for a few months and then take it out to see what can one now not be able to hear from their favorite tracks might be a better way to conclude.
   
  I don't trust professional reviews and all those fancy specs on cables myself and I will be part of those who will gently snigger at those who actually bought the ~USD4k Locus Design cables myself (unless I am Abramovich of course)
   
   
  Nonetheless, I am glad for those who actually take the first step out to get a good USB cables (not snake oil or cheap marketing gimmicks like monster/kimber) to prove the hypothesis which good USB cables make no difference is true.
   
  If I can prove that or design a way to make people realize their digital cable actually make no difference, I could open an audio healing clinic to treat people suffering from placebo and earn big bucks and make many big brands' digital cable business wings close down. That might be a good business that I could venture into when I graduate =)
   
  Parroting what many others have said and thereby firmly concluding that digital cables make no difference add no value at all.


----------



## upstateguy

Quote: 





uelover said:


> <snip>
> Nonetheless, I am glad for those who actually take the first step out to get a *good USB cables*......
> <snip>


 
   
  I use Dayton 1M usb cables and Dayton 1.5ft and 3ft digital cables.  Are they "good" cables?


----------



## The Pell

Looking at the setups used with the "Cables make a difference" group, its not even an audio signal at that point, its strictly a data stream. If you had a USB cable going OUT from your DAC to <insert device name> there could easily be a difference. Right now, I have a small no name ethernet cable going from a modem to my computer. I never have any dropped packets. Will upgrading the cable to one of these change the way I download content? Will an iTunes song downloaded with one change the sound compared to my cable? It will not, because its not audio at that point. Its just a data stream that needs to be compiled and decoded first. The audio cannot even begin to be decoded until all the data required (this doesnt mean the full track) has been transmitted. Pretty much everyone here spent money on a DAC, yet those arguing that USB cables make a difference apparently have no idea on what a DAC does.
   
  But, in order to stay open minded, has anyone taken the time to objectively test whether or not there is a difference (frequency differences, etc)?


----------



## uelover

Quote: 





upstateguy said:


> I use Dayton 1M usb cables and Dayton 1.5ft and 3ft digital cables.  Are they "good" cables?


 


 @USG: I don't know. I use monoprice cables as the baseline for my comparison since they are pretty affordable, well-built, and widely known. I love them because they perform the job well. But there is something I do not comprehend (as well as all the people out there) as to why digital cables make a difference. I am open to criticism and will even welcome people to my place to have a listen to the difference together. It is a discovery on my part and I am constantly seeking answer to that (which is why I hang around thread like this).
   
  @ The Pell: I think it has been discussed before that there is no error correction in USB audio compared to USB data and in audio streaming timing is important. The length and type of USB cables we use for printer/harddrive doesn't really matter but we gotta be careful when using a 5m long USB cable for our DAC. Our USB port pushes real-time data stream out and the DAC pulls them in via USB (or any other digital cables). What happens in between is of interest.


----------



## drez

EDIT


----------



## tmars78

Quote: 





the pell said:


> Looking at the setups used with the "Cables make a difference" group, its not even an audio signal at that point, its strictly a data stream. If you had a USB cable going OUT from your DAC to <insert device name> there could easily be a difference. Right now, I have a small no name ethernet cable going from a modem to my computer. I never have any dropped packets. Will upgrading the cable to one of these change the way I download content? Will an iTunes song downloaded with one change the sound compared to my cable? It will not, because its not audio at that point. Its just a data stream that needs to be compiled and decoded first. The audio cannot even begin to be decoded until all the data required (this doesnt mean the full track) has been transmitted. Pretty much everyone here spent money on a DAC, yet those arguing that USB cables make a difference apparently have no idea on what a DAC does.
> 
> But, in order to stay open minded, has anyone taken the time to objectively test whether or not there is a difference (frequency differences, etc)?


 

 Now lets go with they do make a difference when going from your computer to your DAC, just for the sake of argument, do they also make a difference when running from my external hdd to my computer? Will a $1500 cable open up my soundstage? Will I now experience faster, tighter bass, and  more open, airy treble?


----------



## tmars78

Quote: 





uelover said:


> @USG: I don't know. I use monoprice cables as the baseline for my comparison since they are pretty affordable, well-built, and widely known. I love them because they perform the job well. But there is something I do not comprehend (as well as all the people out there) as to why digital cables make a difference. I am open to criticism and will even welcome people to my place to have a listen to the difference together. It is a discovery on my part and I am constantly seeking answer to that (which is why I hang around thread like this).
> 
> @ The Pell: I think it has been discussed before that there is no error correction in USB audio compared to USB data and in audio streaming timing is important. The length and type of USB cables we use for printer/harddrive doesn't really matter but we gotta be careful when using a 5m long USB cable for our DAC. Our USB port pushes *real-time data stream *out and the DAC pulls them in via USB (or any other digital cables). What happens in between is of interest.


 
  Your second sentence pretty much proves what Pell was saying....that it is not an audio signal, but a data signal. If the usb is only transferring data, how can it affect the audio side of things?


----------



## The Pell

Quote: 





uelover said:


> @ The Pell: I think it has been discussed before that there is no error correction in USB audio compared to USB data and in audio streaming timing is important. The length and type of USB cables we use for printer/harddrive doesn't really matter but we gotta be careful when using a 5m long USB cable for our DAC. Our USB port pushes real-time data stream out and the DAC pulls them in via USB (or any other digital cables). What happens in between is of interest.


 
   
  But its not audio (yet)!


----------



## uelover

Quote: 





tmars78 said:


> Your second sentence pretty much proves what Pell was saying....that it is not an audio signal, but a data signal. If the usb is only transferring data, how can it affect the audio side of things?


 

 One of the argument put forth by others (not me) is that the lack of data correction in USB audio data stream will not ensure the full integrity of the data stream packet that is received by the DAC and that if any data bits are not transferred properly they will just be lost. As such, the DAC will not receive that data and thus will not reproduce that part.
   
  Digital cables don't affect the sound the same way as silver and copper analogue cables.
   
  Low level details are rendered more vividly and more audible (e.g. frogs croaking at the background), vocals sounding more natural and less harsh at the edges, backgrounds are darker. These are some of the improvements I noticed from USB cables.
   
  Debating on USB cable's significance over forum is redundant:
  1) one side of the camp tried to come out with scientific explanation (not conclusive at the moment) and reject the notion without even hearing for themselves.
  2) the other side of the camp heard of the difference and are accused of suffering from placebo effect because there is no hard evidence to showcase the difference they heard.
   
  Further debates will just lead to the same outcome as any other threads on USB cable because nobody has anything valuable to contribute but are just debating over the same old stuffs.
   
  This leads us back to OP's question: Don't get why "Audiophile" USB Cable would improve sound quality".


----------



## upstateguy

Quote: 





uelover said:


> @USG: I don't know. *I use monoprice cables as the baseline for my comparison *since they are pretty affordable, well-built, and widely known. I love them because they perform the job well. But there is something I do not comprehend (as well as all the people out there) as to why digital cables make a difference. I am open to criticism and will even welcome people to my place to have a listen to the difference together. It is a discovery on my part and I am constantly seeking answer to that (which is why I hang around thread like this).


 
   
  What you said is quite confusing.
   
  Are you saying that a $3 monoprice digital cable sounds the same as the Oyaide cable in your sig or that your Starlight usb cable sounds the same as a .98 cent monoprice usb cable?
   
  USG


----------



## uelover

Quote: 





upstateguy said:


> What you said is quite confusing.
> 
> Are you saying that a $3 monoprice digital cable sounds the same as the Oyaide cable in your sig or that your Starlight usb cable sounds the same as a .98 cent monoprice usb cable?
> 
> USG


 

 Sorry if I have confused you. I mean monoprice cables are hard to beat for their price and quality but the cables that I am currently using are more resolving.
   
  I will not recommend anyone to upgrade their cables until they have a good DAC/AMP/Speakers/Headphones. I guess this is the general rule of thumb for cables because the cables are just bringing out the potential of the system.


----------



## upstateguy

Quote: 





uelover said:


> Sorry if I have confused you. I mean monoprice cables are hard to beat for their price and quality but *the cables that I am currently using are more resolving.*
> 
> I will not recommend anyone to upgrade their cables until they have a good DAC/AMP/Speakers/Headphones. I guess this is the general rule of thumb for cables because the cables are just bringing out the potential of the system.


 
   
  Now this is even more confusing.
   
  My understanding is that the fidelity of a digital stream is determined by sample rate and bit depth.  I don't understand how your cables can squeeze more sample rate or bit depth out of a digital stream than the monoprice cables?


----------



## uelover

Quote: 





upstateguy said:


> Now this is even more confusing.
> 
> My understanding is that the fidelity of a digital stream is determined by sample rate and bit depth.  I don't understand how your cables can squeeze more sample rate or bit depth out of a digital stream than the monoprice cables?


 

 This puzzles me too. I see it as better cables not squeezing/adding more data into the data stream but being able to carry them to the destination with less loss. As a result of that, it will appear as if they are more resolving.
   
  I am not trying to explain the physics behind it but am looking for a convincing reason myself too.


----------



## upstateguy

Quote: 





uelover said:


> This puzzles me too. I see it as better cables not squeezing/adding more data into the data stream but *being able to carry them to the destination with less loss.* As a result of that, it will appear as if they are more resolving.
> 
> I am not trying to explain the physics behind it but am looking for a convincing reason myself too.


 

 I want to go back to the last statement for a second: *the cables that I am currently using are more resolving.*
   
  I'm not sure I fully understand what you mean by resolving.   I have an amp that is more resolving than one of my other amps, so I know amps resolve. But I'm not sure cables resolve.  They transmit packets.  If they fail to transmit and a packet is lost we get a drop out.  So, are you saying is that your cables are less prone to drop outs???


----------



## uelover

Quote: 





upstateguy said:


> I want to go back to the last statement for a second: *the cables that I am currently using are more resolving.*
> 
> I'm not sure I fully understand what you mean by resolving.   I have an amp that is more resolving than one of my other amps, so I know amps resolve. But I'm not sure cables resolve.  They transmit packets.  If they fail to transmit and a packet is lost we get a drop out.  So, are you saying is that your cables are less prone to drop outs???


 

 Hey. Explanations from what I have read are that certain minute details could not be heard on certain cables because 1) that wave signal gets distorted/lost or 2) arrived at the wrong timing.
  Those explanations may be false. Who knows.
   
  I will repeat this statement again: I am not trying to explain the physics behind it.
   
  I have no idea, absolutely no idea, as to why USB cables sound different.
   
  You can ask me to explain, and I will tell you the same thing - I don't know why.
   
  What I want to say is that USB cables do make the different. How it achieves it and why is that the case, we are all waiting for that answer.


----------



## upstateguy

Quote: 





uelover said:


> Hey. *Explanations from what I have read are that certain minute details could not be heard on certain cables because 1) that wave signal gets distorted/lost or 2) arrived at the wrong timing.*
> Those explanations may be false. Who knows.
> 
> I will repeat this statement again: I am not trying to explain the physics behind it.
> ...


 

 I'd like to explore this a little more.  Do you have any links to those explanations?


----------



## The Pell

[size=medium] 
  For those of you out there that do believe that the cable makes a difference... Wouldn't it be pretty easy to test the sonic difference by making a test audio file with different frequencies, and then setting up a mic by one of the drivers to record the audio played through each cable? Although it wouldnt be 100% scientific, I would assume that done a bunch of times, we should be able to see a difference of the waveforms of the recording.
   
  And, for another test to check data loss.... If you were to compare the time it took to transfer a very large file several times from one drive to another using two different cables, if the cables really do make a difference, there should be consistency with the copy time of the expensive cable, and the cheap cable should have a large variance from one copy to the next. I think between those two tests, which can be done at home with a little preparation, we should have a good idea on whether or not they make a difference.
   
  The biggest question for those that love the expensive cables, what would your response be if there was true scientific proof (beyond some minor home-based tests) that the cables truly did nothing, and the effect was psycho-somatic? And for the non-believers, what would your response be if there was true scientific proof of sonic changes?​[/size]

  Quote: 





uelover said:


> What I want to say is that USB cables do make the different. How it achieves it and why is that the case, we are all waiting for that answer.


 

 I would think that if there was a measurable (aka real) benefit, companies would eat it up and advertise the hell out of it. I went to the product pages of all the USB cables mentioned in this thread (and a few others), and not a single one mentioned anything about sonic differences, only that the cable is the best ever and will provide the best listening experience. I could not find a single objective statement on how the listening experience would change. Outside of the audio world, these kind of sales are typically called scams.


----------



## DaBomb77766

It would probably be best to hook it up directly to the mic-in or line-in of your pc instead of running it through a mic.  I'd be interested to see how it would turn out, but I'm not sure if such a test would be allowed on this forum.


----------



## The Pell

Quote: 





dabomb77766 said:


> It would probably be best to hook it up directly to the mic-in or line-in of your pc instead of running it through a mic.  I'd be interested to see how it would turn out, but I'm not sure if such a test would be allowed on this forum.


 


  Yeah, that would be easier. I've been awake for too long today to apply common sense.


----------



## upstateguy

Quote: 





the pell said:


> For those of you out there that do believe that the cable makes a difference... Wouldn't it be pretty easy to test the sonic difference by making a test audio file with different frequencies, and then setting up a mic by one of the drivers to record the audio played through each cable? Although it wouldnt be 100% scientific, I would assume that done a bunch of times, we should be able to see a difference of the waveforms of the recording.
> 
> And, for another test to check data loss.... If you were to compare the time it took to transfer a very large file several times from one drive to another using two different cables, if the cables really do make a difference, there should be consistency with the copy time of the expensive cable, and the cheap cable should have a large variance from one copy to the next. I think between those two tests, which can be done at home with a little preparation, we should have a good idea on whether or not they make a difference.
> 
> ...


 

 That's interesting..... 2 extra paragraphs appeared that weren't there when I quoted your post.....
   
  Another way to approach this might be to investigate what uelover is reporting, rather than discounting it.  Certainly he is hearing something and has developed preferences for certain cables.  He says "more resolving" I'm still not sure exactly what he's hearing.
   
  About making recordings.  Prog Rock Man posted about a tool called the Audio DiffMaker.  Is this what you're referring to?  You make a recording with one cable, change cables and make a second recording.  The program will null out everything that is the same and you are left with only the difference between the two cables.


----------



## The Pell

I found the edit button 
   
  Also, anyone know why the top part of that text is in a white box?


----------



## DaBomb77766

Quote: 





the pell said:


> I found the edit button
> 
> Also, anyone know why the top part of that text is in a white box?


 


  Did you type it somewhere else then copy and paste it here?


----------



## upstateguy

see above, I added to the post also.


----------



## drez

[size=medium]edit​[/size]


----------



## upstateguy

Quote: 





drez said:


> *I think this thread should be named *"why don't cable makers justify their USB products in terms of technical, empirical performance"
> 
> Seeing as USB is a digital technology which transmits digital data, I find it baffling that these products are marketed in the same way as analogue products - ie. by describing supposed change in sound characteristics the product brings.
> 
> ...


 

 I think this thread should be named *"Something is happening here but we don't know what it is."*
   
*The only reason I can see for manufacturers taking this approach is:  *that there doesn't seem to be a way to measure what is being reported.


----------



## uelover

@USG: Got it. I will pm you the links when I come across them. Too bad that you are in NY if not I will invite you over for a listen and 
	

	
	
		
		

		
			





 together.
   
  I am not sure if there is a loan program over there in the US where you can take several cables home and listen before deciding if they are worthy to have you purchased them. I took various cables back home to try myself before deciding if I should keep the better one over using monoprice cables.
   
  Of course, skeptics can scorn and laugh off at what I am saying here.
   
  But I want to make a point to those who are open minded to not close off the idea that digital cables will make a difference.


----------



## drez

[size=medium]edit​[/size]


----------



## upstateguy

Quote: 





uelover said:


> @USG: Got it. I will pm you the links when I come across them. Too bad that you are in NY if not I will invite you over for a listen and
> 
> 
> 
> ...


 
   
  Did you hear a difference with each cable you tried?


----------



## DaBomb77766

Quote: 





upstateguy said:


> I think this thread should be named *"Something is happening here but we don't know what it is."*
> 
> *The only reason I can see for manufacturers taking this approach is:  *that there doesn't seem to be a way to measure what is being reported.


 

  
  If you can't measure it, then it isn't happening.  Computers can measure things down the the slightest detail.  Us humans cannot.  Basically, if someone does a scientific test with professional equipment and comes up with no difference, then the cable is making no difference.  It's as simple as that, you can't argue raw data.
   
  Of course, you can argue with the methods chosen to obtain said data, and I think that's probably why DBT is banned on this forum - and such a test would be too.  It'd be better to do that in the "sound science" forum.


----------



## upstateguy

Quote: 





dabomb77766 said:


> *If you can't measure it, then it isn't happening*.  Computers can measure things down the the slightest detail.  Us humans cannot.  Basically, if someone does a scientific test with professional equipment and comes up with no difference, then the cable is making no difference.  It's as simple as that, you can't argue raw data.
> 
> Of course, you can argue with the methods chosen to obtain said data, and I think that's probably why DBT is banned on this forum - and such a test would be too.  It'd be better to do that in the "sound science" forum.


 
   
  You'd think so, but you can't deny that something is going on.


----------



## upstateguy

Quote: 





drez said:


> But there is - the aim of the digital cable as I understand it is to transmit the cleanest and most coherent digital signal possible.  *This can be measured by the amount of jitter present.*  Manufacturers don't publish this data.  I don't know why, but I can speculate as above.


 

 It's debatable how audible that jitter is .


----------



## drez

meh I give up no point putting my neck out to argue over this.


----------



## upstateguy

Quote: 





drez said:


> Read above
> 
> To me there is no doubt that jitter is the prime candidate factor in performance of a digital cable (IMO etc etc.)...


 

 I'm not convinced that cable induced jitter is a problem or even audible in the short runs we use in audio.
   
  But here's something to think about.  Have you considered reflections?


----------



## DaBomb77766

Quote: 





upstateguy said:


> You'd think so, but you can't deny that something is going on.


 


  Well, that something could just be placebo.  I'm not saying that there's necessarily anything wrong with that.  If it works for you, then I'm fine with it.  You claim to tell a difference, so I guess I'll believe you and maybe you really do find a difference.  It's just, I'm skeptical the cable itself is the thing making the difference, but until we have definitive proof either way, arguing isn't going to help anyone here.


----------



## uelover

@USG: They sounded different (I took 3 cables that costs around USD100). I won't go into detail how different they sound nor the brand I tried while obviously WW Starlight was one of them.
   
  Hmm actually what are the so-called professional tests available out to determine whether 2 sources of sound are different? I wouldn't think frequency response graph would be appropriate though.
   
  I don't like the word "audiophile cables" because they can be misleading - what if they took a USD10k snake oil cable which was marketed as "audiophile cables" and then found contradicting evidence that it instead deteriorate SQ? So shall all other USB cables be condemned?
   
   
  Certainly, there are things happening around us that is hard to explain:
   
  1) In spite of criticism that USB cables make no difference to SQ, no USB cable makers come out to refute that criticism.
*Question:* Not possible to furnish hard evidence or is it that the criticism is true?
   
  2) More and more cable makers are joining the race and making expensive (touted high quality) USB cables, increasing the competition in the market.
*Question:* Why bother engineering and making something that is no better than stock USB cable and tarnishing their own reputation, or is it that there are simply too many rich fools out there to cheat their money? Obviously the market share for each company is shrinking due to new-entrants.


----------



## 00940

Quote: 





> Originally Posted by *The Pell* /img/forum/go_quote.gif
> 
> For those of you out there that do believe that the cable makes a difference... Wouldn't it be pretty easy to test the sonic difference by making a test audio file with different frequencies, and then setting up a mic by one of the drivers to record the audio played through each cable? Although it wouldnt be 100% scientific, I would assume that done a bunch of times, we should be able to see a difference of the waveforms of the recording.
> And, for another test to check data loss.... If you were to compare the time it took to transfer a very large file several times from one drive to another using two different cables, if the cables really do make a difference, there should be consistency with the copy time of the expensive cable, and the cheap cable should have a large variance from one copy to the next. I think between those two tests, which can be done at home with a little preparation, we should have a good idea on whether or not they make a difference.
> The biggest question for those that love the expensive cables, what would your response be if there was true scientific proof (beyond some minor home-based tests) that the cables truly did nothing, and the effect was psycho-somatic? And for the non-believers, what would your response be if there was true scientific proof of sonic changes?


 

 - To see if the cables make an absolute difference, running a distortion analysis by sending the DAC output into a high quality ADC would be better. Mic and headphones distortions would probably dominate your results. Downside is that nobody in that discussion has the required equipment.
  To see if cables make an audible difference, you'll need extensive blind testing I'm affraid. Upsides is that the equipment is easier to gather on a hifi forum.
   
  - Data loss is fairly irrelevant to the discussion. The differences in sound put forward by those who claim to hear a difference in between USB cables cannot possibly come from data loss. Furthermore, your test is invalid as, in data transfer and unlike USB audio transfer, the USB bulk protocol provides for error correction. Your files will be identical no matter how cheap the cable is. There's a reason I can transfer 300go in  backup each week without losing a single bit.  
	

	
	
		
		

		
			




   
   
  I'm going to repeat myself...
   
  Here are the identified possible reasons for absolute differences, they only apply to the USB audio protocols, not to the transfer mode:
   
  -1- Waveform distortion: due to its physical properties, the cable can possibly affect the square waves, in interaction with the source and receiver (from that point of view they form an analog system). This in turns affect the accuracy of the recovered system clock fed to the DAC chip. This in turns affects the accuracy of the digital to analog conversion.
  -2- Interaction in between power supply lines and data lines: it has been measured that 1Khz spikes coming from the data lines can couple into the power supply lines and that the longer the cable, the stronger the effect. Such spikes could maybe be directly heard as noise depending on the dac's pcb layout. Such spikes could also affect the accuracy of the ICs inside the dac, resulting either in increased jitter (for the clock or the receiver chip) or directly in higher distortion (for the dac chip and the opamps of the analog section).
  -3- Rfi shielding: the usb cables are quite susceptible to high frequency noise pick-up (a reason among others why long runs cannot be used). Noise making its way into data line can perturbate the receiver chip, causing early/late triggers, resulting once again in a poorer system clock. If the noise couples into the power supply lines, see -2-.
  -4- HF noise attenuation: the source computer signal's quality can vary widely. HF noise can find its way on the various USB lines. A cable attenuating this HF noise could thus have an impact. It could however interacts with -1-.
   
  All these are sound engineering reasons and have been measured or could be, given time and the proper (read expensive) equipment. The fact that USB cables affect the analog output of the DAC seems to have been proven by measurements by Paul Miller for the january issue of Hifi News (if anyone has the article, I'd love to read more than hearsay).
   
  HOWEVER, the existence of a *technical difference* in between cables does NOT prove the existence of an *audible difference*. It is even more so as the differences outlined above are fairly small and that cables manufacturers don't seem to bother measuring the actual differences their cables make. And you have to keep in mind before any generalization that USB audio uses 3 different protocols with various levels of weakness to those problems, that the USB receiver chips are very different and that DACs are coming from a bazillion different manufacturers who pay more or less attention to their designs.


----------



## upstateguy

Quote: 





dabomb77766 said:


> Well, that something could just be placebo.  I'm not saying that there's necessarily anything wrong with that.  If it works for you, then I'm fine with it.  *You claim to tell a difference*, so I guess I'll believe you and maybe you really do find a difference.  It's just, I'm skeptical the cable itself is the thing making the difference, but until we have definitive proof either way, arguing isn't going to help anyone here.


 

 I'm not making any claims.
   
  Try the Audio DiffMaker.  See if you can get some proof.


----------



## drez

Quote: 





00940 said:


> -1- Waveform distortion: due to its physical properties, the cable can possibly affect the square waves, in interaction with the source and receiver (from that point of view they form an analog system). This in turns affect the accuracy of the recovered system clock fed to the DAC chip. This in turns affects the accuracy of the digital to analog conversion.
> -2- Interaction in between power supply lines and data lines: it has been measured that 1Khz spikes coming from the data lines can couple into the power supply lines and that the longer the cable, the stronger the effect. Such spikes could maybe be directly heard as noise depending on the dac's pcb layout. Such spikes could also affect the accuracy of the ICs inside the dac, resulting either in increased jitter (for the clock or the receiver chip) or directly in higher distortion (for the dac chip and the opamps of the analog section).
> -3- Rfi shielding: the usb cables are quite susceptible to high frequency noise pick-up (a reason among others why long runs cannot be used). Noise making its way into data line can perturbate the receiver chip, causing early/late triggers, resulting once again in a poorer system clock. If the noise couples into the power supply lines, see -2-.
> -4- HF noise attenuation: the source computer signal's quality can vary widely. HF noise can find its way on the various USB lines. A cable attenuating this HF noise could thus have an impact. It could however interacts with -1-.
> ...


 

 Thsnks so much for posting this.  I couldn't agree more.


----------



## The Pell

Quote: 





00940 said:


> - Data loss is fairly irrelevant to the discussion. The differences in sound put forward by those who claim to hear a difference in between USB cables cannot possibly come from data loss. Furthermore, your test is invalid as, in data transfer and unlike USB audio transfer, the USB bulk protocol provides for error correction. Your files will be identical no matter how cheap the cable is. There's a reason I can transfer 300go in  backup each week without losing a single bit.


 

 Im not testing file size, I would test transfer time. If there is way more error correction going on with a cheaper cable, the file transfer would take longer.


----------



## DaBomb77766

http://www.passmark.com/products/usb2loopback.htm
   
  You could try something like this, but it's still extremely imprecise to use such a method it since the problem could come more from the PC you're using than the cable itself.  Still, if there's a drastic difference from one USB cable to another, especially if the so-called "audiophile" cables have less error correction, then it would be interesting.
   
  At any rate, testing error correction rates based on transfer times would be kind of ridiculous.  You'd have to have a perfectly neutral testbed with absolutely nothing running in the background, and only the USB service and filesystem up and running.  Otherwise other services or programs running in the background could significantly skew the results.


----------



## Hennyo

I NEED to hop in here! I am somewhat new to Headfi, it being a 5month old hobby for me, but I have spent about 3000$ on Headphone equipment and a soundcard for kicks. (1800 after I returned wires). I traveled to the 4 largest audio shops in my STATE (for fun) just to demo new (pretty much every modern) incredibly expensive product of all kinds with headphones I've demoed a grand total of probably somewhere around 20 aftermarket cables.
   
  Midway through this journey about 2 1/2 months ago, I spent $1200-1400 on _*signal *_cables (this does _not_ including Headphone my $580 of headphone recabling, source cable only) of all colors, shapes and forms. -_EDIT_: for post coherence reasons I've refrained from listing the plethora-.
   
  NOW, I too was skeptical to begin with, "A cable?!!? Really? How's that going to improve my experience?!"
   
  I'm here to tell you that ALTHOUGH "It's just 1's and 0's" This does NOT hold true for audio the same way it does for video. 00940's post = angelic sending concerning this topic and explains (most) of the science behind it. This is a myth that needs to be dispelled - BADLY. Anyone who tries to play Dr. Phil with the "cable believers vs nonbelievers" argument has _very obviously_ _never,_ _ever...EVER_ tried a third party cable of any sorts, and they are denying their real systems potential.
   
  Ask anyone and I do mean _anybody_ who personally own a 2k+ rig built around 1-2 headphone, anybody who builds chips for a living, anybody who's heard credible (not dirt cheap) aftermarket cables. The difference is _astounding_, no buts about it: the difference can easily be ASTRONOMICAL!!!!!!!!!!!
  Without Custom cabling Headphones lose their edge to speakers... It's a sad truth, but Custom cabling allows Headphones to be taken to a whole new level, and _THAT _is where the true bang for buck sound is in headphones. I would _vehemently_ "reasonably debate" with any cable "nonbeliever" *cough, *cough*
   
  If you do NOT (LOOOLL) believe me then please, by all means, TRY IT! Signal cable is JUST AS important as what DAC, amp, or source you choose, and I do mean JUST AS imporant. Sadly recabling is terribly underrated, heh, accept by those who've actually tried or done it. Everyone else who has had the opportunity..... is terribly naiive to the level of performance their system_ could have. _It really is terribly sad and somebody needs to set the record straight.
   
  That "believer vs non-believer" argument is blasphemous  unto the audio religion itself. If you are devoted to the sound, don't you think you owe it to yourself to at least try it out and discern with your own ears?!?!?!?!?!?!?!?!? OF COURSE you do! So get out there and TRY IT. If you don't like it then just RETURN it. (pew pew) 
	

	
	
		
		

		
		
	


	




 I hope this incredibly passionate rant was somewhat informative and can lay to rest the cable questions. (I am sick of seeing cable "makes difference or no" questions).
   
  I could go on to describe every cable as I heard it, but that would be boring (EDIT: to me 
	

	
	
		
		

		
		
	


	




) and almost pointless. It's too nitty-gritty to post that many reccomendations online. Cabling is just one of those things you have to try out for yourself. I will say that USB signal cable has come LEAPS and BOUNDS in the last year or so, and it is widely believed among those in the industry that the new offerings do match and _even surpass_ the traditional "coax is supreme" cable at a fraction of the price. It's also quite a lot cheaper than coax of similar quality (i.e. 500$ usb cable = about 680-800$ coax cable, and it still edges those coax cables out.... and Glass fiber?! Don't even go there for headphones. 550-700$ per cable that don't even take the signal off your digital passthroughs clock? That's one of USB's two strengths(!!!!) Count me out when such things exsist as the Carbon, Coffee, and Diamond Audioquest USB cables. Wireworld also makes (from what I've heard good cables that sell too.
  Audioquest really put some effort into their 2 high end USB's. TRY CARBON usb if you're curious about aftermarket signal cable, hell or even cinnemon would float your boat into new waters, but I've found carbon be the best bang (incuding dollar for performance) for buck regarding any setup or chain. Kimber Cable also makes two Great usb cables) Theirs are solid copper and 6.25% plated silver.
   
  Overall in short, the best 2 cables to my ears (and also 2nd and 3rd opinion freinds who had no vested interest in the purchases whatsoever) were the Diamond and Coffee USB cables by Audioquest. Yes, it's a lot to sink into a cable, but please, please, at least educate yourself by giving products like them a shot. Your ears DO NOT deserve to live in darkness. Not with all the money you've already poured into your setup desperately searching for the best sound. Cables are one of the main strengths that make headphones what they are: in a word, EPIC joy. ;*)


----------



## Hennyo

I am 18, I am by no means rich, and have lived on my own for the last 3 years. I am just devoted to absolute excellence in whatever I'm interested in/wish to pursue. ^^


----------



## svyr

dabomb77766 said:


> http://www.passmark.com/products/usb2loopback.htm
> 
> You could try something like this, but it's still extremely imprecise to use such a method it since the problem could come more from the PC you're using than the cable itself.  Still, if there's a drastic difference from one USB cable to another, especially if the so-called "audiophile" cables have less error correction, then it would be interesting.
> 
> At any rate, testing error correction rates based on transfer times would be kind of ridiculous.  You'd have to have a perfectly neutral testbed with absolutely nothing running in the background, and only the USB service and filesystem up and running.  Otherwise other services or programs running in the background could significantly skew the results.




re: error correction rates... 

Only bulk mode devices (musiland seems to be the only one I know to use it for audio) actually do both error detection and correction. (crc-ish + 'ltd hardware' retransmission and data delivery guarantee, but not latency guarantee). Technically it seems to be an overlay 'bus' they use to ship the data over to the device and then feed the reconstructed data to the DAC chip. Latency is 'technically' not guaranteed, but there should usually be enough bandwidth?

Neither sync, async or adaptive mode usb audio devices seem to. These all have a 'guaranteed latency', but as a result, no retransmission (have a look at the usb spec docs http://www.usb.org/developers/docs/usb_20_021411.zip usb20 pdf sec 4.7)

(errr, might have error detection - bit parity of some sort or whatever else, but no retransmission) 



> The timely delivery of isochronous data is ensured at the expense of potential transient losses in the data
> stream. In other words, any error in electrical transmission is not corrected by hardware mechanisms such
> as retries. In practice, the core bit error rate of the USB is expected to be small enough not to be an issue.




I really wonder if the more expensive 'audiophile' cables even conform to the USB specs standards ...So yes, good point about the possibility of it measuring worse... A good starting point might be seeing whether they conform to those standards first  
I'm sure the product makers will then market it the cables as warm and fuzzy and unique . The errors make the sound analog and natural ...




>I am 18, I am by no means rich, and have lived on my own for the last 3 years. I am just devoted to absolute excellence in whatever I'm interested in/wish to pursue. ^^

I see a shiny power and usb cable in your future


----------



## DaBomb77766

I'm just gonna ignore Hennyo and pretend he never posted.
   
  Anyway, for "true" audiophlie usages, I see no reason why latency should be any issue whatsoever.  Error correction and retransmission would absolutely fix every problem there is to do with packet loss in the cable.  If they introduce a fraction of a second of lag, it's not going to make any effect on audio quality whatsoever, at least when you're only listening to music, and the error correction will simply remove the cable as a source of errors.  I see no reason why this wouldn't work.  If I can transfer my entire 32GB audio library to an external hard drive without any corruption of the files, then the same should be said for USB transmission of audio to a DAC.
   
  There must be some reason why this hasn't been done before though.  If anyone knows, feel free to tell me.


----------



## svyr

dabomb77766 said:


> I'm just gonna ignore Hennyo and pretend he never posted.
> 
> Anyway, for "true" audiophlie usages, I see no reason why latency should be any issue whatsoever.  Error correction and retransmission would absolutely fix every problem there is to do with packet loss in the cable.  If they introduce a fraction of a second of lag, it's not going to make any effect on audio quality whatsoever, at least when you're only listening to music, and the error correction will simply remove the cable as a source of errors.  I see no reason why this wouldn't work.  If I can transfer my entire 32GB audio library to an external hard drive without any corruption of the files, then the same should be said for USB transmission of audio to a DAC.
> 
> There must be some reason why this hasn't been done before though.  If anyone knows, feel free to tell me.




yea I'm an under an impression that there's more than enough bandwidth for the bulk mode devices to do the retransmission and that they're actually preferable over isochronous USB ones.. And yes it should make the cable a non-issue as long as it's not bad enough to do something like let's say 2x the audio bandwidth (a lot less than the USB 2 spec anyway  not to mention if the loss rate is so high, using that on an isochronous device instead will probably be heavily audible since there's no error correction there) (For bulk mode audio, like musilol, since it's playback and not recording, the latency is a non-issue for me too. In any case, there won't be a drop out unless the bulk data buffer is empty (probably IO or CPU resources unavailable, and those conditions will most like would cause isochronous devices to also drop samples)). 

The problem is, I literally have only seen it on the musiland devices ... and um, MD11 was by no means otherwise lovely  (their QC for software and hardware seems to be 'this probably looks good, so lets make 100s of units and make people download 100s of copies of this driver/firmware that doesn't actually install/has channels reversed but it's probably all bit perfect and great'  )...


----------



## upstateguy

Quote: 





uelover said:


> @USG: They sounded different (I took 3 cables that costs around USD100). I won't go into detail how different they sound nor the brand I tried while obviously WW Starlight was one of them.
> 
> Hmm actually what are the so-called professional tests available out to determine whether 2 sources of sound are different? I wouldn't think frequency response graph would be appropriate though.
> 
> ...


 
   
*I won't go into detail how different they sound nor the brand I tried*

 I'd love to hear the details.
   
*what are the so-called professional tests available out to determine whether 2 sources of sound are different......*
   
  Although Nick_Charles informed me that it can generate some false positives, the *Audio DiffMaker*, that Prog Rock Man posted about, is probably the easiest tool to use.  You record a WAV with one usb cable or interconnect in place, then change cables and record the same thing again.  The program nulls out everything that is the same and you are left with only the differences.  All the usual questions are covered on their web site.
   
  A few years ago I was under the impression that I could tell the difference, in my M^3, between an 8610 oamp and a 637/627.  I e-mailed AMB about this and he told me that they would sound the same in an M^3.  Unconvinced, I sent him a WAV of each opamp to demonstrate the differences I clearly could hear.  He put the stereo streams into audacity and turned each one into mono.  Then he took the 2 mono streams and made a new stereo stream.  Now he inverted 1 of the streams and lined them up by eye.  The result was a -45dB WAV of the difference between the 2 WAVs, I sent him.  The verdict:  Any difference between those 2 opamps was inaudible.
   
  I may not have gotten all AMB's steps right, but now we have the *Audio DiffMaker* that does the same thing for us automatically.
   
*Certainly, there are things happening around us that is hard to explain:*
   
*1) In spite of criticism that USB cables make no difference to SQ, no USB cable makers come out to refute that criticism.*
*Question: Not possible to furnish hard evidence or is it that the criticism is true?*
   
  Here is an opportunity for those who have high end cables to begin to generate some data showing that differences exist, or not if they don't.   I think that we can agree that any data that can show differences is better than the absolutely no data situation that exists now.  Another advantage is that these results should be relatively reproducible.  If you find a notable difference between the Starlight cable and the one it replaced, others should be able to get similar results with that cable.
   
  Here's what you need.  A cable of your choice that goes from the headphone output of your amp to the mic input of your computer.  If you only have a laptop you might need a usb mic input for stereo recording.  And of course, some high quality cables to test.
   
  Here is the cable I used.


----------



## upstateguy

Quote: 





dabomb77766 said:


> I'm just gonna ignore Hennyo and pretend he never posted.
> 
> Anyway, for "true" audiophlie usages, I see no reason why latency should be any issue whatsoever.  Error correction and retransmission would absolutely fix every problem there is to do with packet loss in the cable.  If they introduce a fraction of a second of lag, it's not going to make any effect on audio quality whatsoever, at least when you're only listening to music, and the error correction will simply remove the cable as a source of errors.  I see no reason why this wouldn't work.  *If I can transfer my entire 32GB audio library to an external hard drive without any corruption of the files, then the same should be said for USB transmission of audio to a DAC.*
> 
> There must be some reason why this hasn't been done before though.  If anyone knows, feel free to tell me.


 
   
  I think there might be a difference between the data stream sent to your external HD and the PCM stream sent to your dac. 
   
  Someone with better knowledge please chime in and clear this up.


----------



## Prog Rock Man

If USB cables failed to transmit audio data uncorrupted would the result be -
   
  A - poorer sound quality
   
  B - the sound cutting out, crackles, pops
   
  as the signal has not arrived as it should be?
   
  I think the answer is B as how could corrupted data affect clarity, bass, treble as that would suggest the error is only one part and consistently one part of the data stream. Any corruption would affect the whole signal either for a short period of time, so possibly causing a crackle, or longer so cutting out the sound altogether.


----------



## jackmccabe

People perceive a difference due to cognitive bias and visual cues.
  When someone actually blind tests a set of usb cables and can actually hear a difference between a £0.99 cable and a £60+ cable,
  Then and only then will I rethink my cable skepticism.


----------



## dvw

Quote: 





prog rock man said:


> If USB cables failed to transmit audio data uncorrupted would the result be -
> 
> A - poorer sound quality
> 
> ...


 

 B is the obvious and logically correct answer. Error are random. In a digital system, the signal is a word that's 16 bit long. Consider this, if you say the noise is lower, this means the error will occur only at the LSB. If you say you have better high, this mean the cable will have to create a new value (word) at certain high frequency and have to have explicitly corresponding value because too large or too low will create a pop and click noise instead.
   
  One other factor to consider. Unlike analog cable, USB cable actually has a standard. This means the cable companies and the USB community worked together to engineer a specification. As long as the cable meets the specification, the USB will work. If anyone has a better cable, they can make a proposal to change this standard. Imagine the money you'll make if you actually have a superior technology in this USB cable. There are over a Billion USB device shipped per year. If you only make one dollar each, you still make a billion dollar. So just from the economic alone, a $1200 dcable does not make sense.


----------



## Mambosenior

Can anyone translate this description of an USB cable into practical terms:
   
  “[XYZ] USB cable is designed with the [XYZ] technology. Clear is the geometry of the Golden Section, but highly refined using state of the art dielectrics and metallurgy. Clear is the vision of perfect geometry. The metallurgical advancements and metal testing techniques that have evolved from this project are finding applications far beyond anything ever imagined. Insights into the basic conductor dielectric relationship have lead to a new frontier of understanding and an associated patent, but it is the dramatic silencing of the cables themselves and the completely unimaginable improvement in depth and clarity of sound that was the real reward. ”
   
  What I am deciphering is: mumbo & jumbo. (I could be wrong.
	

	
	
		
		

		
			





)


----------



## jackmccabe

Here is my translation "Ignore reality this cable is definitely worth (insert ridiculous price) because it is shiny, magical and defies reality and science"


----------



## travisg

If you have never tried an audiophile grade USB cable in your system and would rather just say that it makes no difference because you like to spit out digital specs and hyperbole. Please please Shut-up! You do not have the right to speak. If you have tried a superior grade USB cable and found it to be no better than your Walmart cable, by all means continue.


----------



## jackmccabe

Yes, I have tried audiophile usb cables they make absolutely no discernible difference whatsoever, if someone could consistently pick out an audiophile usb cable in a blind test I would be gob smacked.


----------



## travisg

Awesome at least you have tried them. Thank you for your well informed opinion.


----------



## jackmccabe

Wow, thank you for being so reasonable about such a hotly debated topic.


----------



## uelover

@USG: Is there a mac equivalent of Audio DiffMaker? I have no mics with me either. Let me see what I can do about it.
   
   
  @Prog Rock Man: I don't think B would be a plausible answer unless a whole chunk of data got corrupted/lost. I guess when we transfer data from our comp to an external harddrive with any USB cables, we are safe because there is error correction but I won't actually expect the error rate to be so large if not the bulk of time will be allocated for error correction instead of transfer.
   
  With stock USB cables, perhaps certain data here and there, maybe (5%-10% IDK), are not arriving at the DAC. They may not be an entire bloc off a data stream at any certain specific timing so we will not hear a sudden cut out/popping sound in between our audio. Nonetheless the bulk of the data will still get received by the DAC at any point of time. As a result, stock USB cables are still readily usable.
   
  Above is my guess. Please correct me if I am wrong.
   
   
  A simple search in google for Wireworld Starlight USB Review will bring you to computeraudiophile threads with a handful of people claiming that it made an improvement so far in their system. So far I haven't come across anyone who had owned it but condemned it for a waste of their money.
   
  But yeah jackmccabe, we welcome people like you who have heard and tried and then report back based on your own empirical experience. I will like to hear more of such accounts, including your setup and USB cable tried =)
   
  What I cannot stand is people happily criticizing, scorning and/or even quoting wrong facts. I guess that Hennyo and travisg got really pissed by that too.


----------



## Mambosenior

My quotation above (from a real advertisement of an USB cable) was only meant to illustrate the degree of fantasy and hyperbole that permeates this niche market. In reading through it, any sensible person can deduce that concrete information (i.e.: the type and make of the wire(s) used, the electrical properties, etc.) is nowhere to be found. It is an appeal by the manufacturer to accept the product only on faith.
   
  As I mentioned before, I do use a modestly over-priced USB cable. At the time I bought this particular cable I bought a second, much less expensive (about $200 cheaper) USB cable from the same maker. After listening to both over two systems, speaker-based and HP, I honestly can not tell any difference between the cables. I have owned both cables for over two years so it isn't a case of hearing each just once or twice. I bought the advertised jargon on faith and suspended disbelief as I sent my Paypal. I believe that this psychological conundrum is at the center of why we think we hear a difference since critical empirical evidence is not to be had. Surely, you must have noticed the religious and/or metaphysical overtones of “...the Golden Section.”
   
  Why I haven't sold the more expensive cable if I don’t hear the difference, you may ask? Well. Procrastination...and a certain morbid fascination with the great unknown.
	

	
	
		
		

		
		
	


	




)


----------



## jackmccabe

There is no way a usb cable loses 5-10% of the data, it is more like 0.0001% this is clearly inaudible.
  If we look at measurements of usb cables there is absolutely no evidence that they would make an audible difference.


----------



## uelover

Mambosenior - I agree with you about the fallacy of marketing. That is why I never bother to read what the manufacturer says about its own product nor their advertisement. The only time I will buy a cable is after I have tried them. If I can't, no way I will buy. i.e., Locus Design Cable. I don't even have the equipment to test the actual content of the cables and whether the way they are built as advertised.


----------



## uelover

@USG & travisg: I will retire from this thread and look for better explanations for the answer I am seeking. I don't think I can find them here and I don't think its worth my time here either.


----------



## tmars78

Quote: 





travisg said:


> If you have never tried an audiophile grade USB cable in your system and would rather just say that it makes no difference because you like to spit out digital specs and hyperbole. Please please Shut-up! You do not have the right to speak. If you have tried a superior grade USB cable and found it to be no better than your Walmart cable, by all means continue.


 


  There is no such thing as a superior grade. USB cables have to be built to a certain spec. If the cable is built to that spec, it, and all others like it, are going to do the same thing. I find it hard to believe that some audio company has somehow made a cable that out performs and has some magical property that the ones engineers have designed, and came up with a spec for. The reason for this specification? To ensure that the cable works properly and functions as it should. Saying you plugged in a cable, and heard a difference, does not make you any more qualified to comment. That's like me saying I am qualified to coach a football team cause I have watched games on tv.


----------



## DaBomb77766

Guys, you have to note that you're not allowed to post blind tests here, and I think audiodiffmaker counts too.  Asking kindly for someone who knows the rules isn't going to make them post something they can't post.  If you want to bring this up to blind testing, bring it to the sound science board.
   
  Anyway, I still don't see why they don't just use error correction for audiophile USB DACs.  It makes perfect sense to me why they should.


----------



## svyr

> With stock USB cables, perhaps certain data here and there, maybe (5%-10% IDK), are not arriving at the DAC. They may not be an entire bloc off a data stream at any certain specific timing so we will not hear a sudden cut out/popping sound in between our audio. Nonetheless the bulk of the data will still get received by the DAC at any point of time. As a result, stock USB cables are still readily usable.




lol... the wildest speculation I've seen in a long time. Would be extremely funny if they designed a to-spec cable in the standard to waste 5-10% bandwidth...

Other than that the arguments of 'omg look at the reviews no one wants to admit they're wasted $400 on a cable' or 'omg if you have a 2k source, why not get a $400 usb cable because you can' are not particularly appealing and the response is: Placebo and self-dellusion are much more appealing ones  as is "don't feed the bs sales by buying into the 'why not try and see'"). But hey, maybe if they have a loaner program  and would like to send one to someone with an oscilloscope 


>others who are making 'expensive snake oil' usb cables to rid themselves of their market competitors?

Takes money. Makes you a target since the burden of proof is on the seller and the competing products don't seem to furnish any...
Even when taunted to. Seems like they could refute those 'wild accusations we make' and clear their good name  ...


I really wish someone would finally conduct an test for USB cables and post some RMAA graphs to show any effects on the FR or THN+D  to settle the issue



>Anyway, I still don't see why they don't just use error correction for audiophile USB DACs. It makes perfect sense to me why they should.

because the standard usb chips support max of async or sync or adaptive mode isochronous usb transfer and to do the bulk mode including ec and re-transmission you need to write custom firmware and drivers and that's expensive and ...well, musiland went through a year+ of release cycles before they had stable ones for MD11 and US02...(and they still don't have a *nix/linux/mac driver)


----------



## DaBomb77766

Hm, one thing that I don't understand about this whole debacle is this:  all digital data is either one amplitude or another.  It's not a full range of them like analog is.  As such, if a cable were to "change" anything, it would either make random bits to drop out or do nothing at all.  It can't simply affect the higher regions or the lows, since it's impossible to tell the difference between one part of the signal to the next other than that it's a "1" or a "0."  Dropping random bits isn't going to "open up the highs" or "extend the lows."  It's simply not physically possible for a digital cable to selectively pick out the bits that "need" to be changed - for that you would need an active decoding chip in the cable that's doing EQ.  Impedance and quality of the copper used shouldn't be able to change audible signals in the same way us humans perceive them.


----------



## svyr

> It's simply not physically possible for a digital cable to selectively pick out the bits that "need" to be changed - for that you would need an active decoding chip in the cable that's doing EQ. 

+1. neither is a faulty cable out of spec affecting a certain FR range is likely at all ...


----------



## codeninja

Once you put enough words into the argument, especially if they include some fancy technical terms, you can manage to come up with arguments for pretty much anything.  Or, at least confuse enough people to stop questioning because they just simply can't understand the statement.  Yes, I'm talking about this case.  The best way of understanding this premium digital cable justification is more of matter of peace of mind than anything else.


----------



## vandaven

First off, this is a very entertaining thread. 
   
  As we all know, in most cases, the USB controller of the computer is not directly inside the USB port.
   
  Let's say that inside my "standard" PC, there are a couple of flimsy wires connecting the USB ports to the motherboard, will an expensive "audiophile" USB cable make up for these (which might degrade my USB sound before it actually reaches the port)?
  (same could be asked in regards to AC cables and poor AC cabling in the house)
   
  Are there certain desktop computers / laptops / motherboards etc. that are more "audiophile" than others? 
   
  Why would a high-priced "audiophile" USB cable only affect expensive audio systems? If the cable really makes a difference, it would affect the sound of any USB sound device, wouldn't it?
   
  For my personal interest on this topic, I will buy a "superior" USB cable tomorrow and test it with a professional USB audio system to see whether it makes a difference or not. 
   
  I guess it is somehow nice to believe in magic, but after I have witnessed a "SACD / DSD" recording last summer (that actually shocked me as an audio engineer who believed that at least the people who engineer that stuff believe in high quality), I am totally positive on the fact that there is a lot of scam going on, and a lot of money is harvested on the back of people that would rather believe in non-sense than actually get some reality check & proof. But maybe that's human nature...


----------



## DaBomb77766

Quote: 





vandaven said:


> First off, this is a very entertaining thread.
> 
> As we all know, in most cases, the USB controller of the computer is not directly inside the USB port.
> 
> ...


 


  Which cable will you buy?  And if you have the time, could you post some comprehensive DBT results in the sound science forum?


----------



## travisg

Just because you have a spec doesn't mean it can't be improved upon. A automobile has a certain spec. An engine or power source,some way to control it and a way for it to move under it's own power,etc,etc. So why does Ferrari or Porsche or Aston Martin bother making any changes to that spec? Why try to improve on a Yugo? Surely a Yugo is an automobile just like an Aston Martin is. But I would like to drive the Aston Martin because they improve on the spec,by using superior materials and build quality. But hey that's just me. To each his own. I'm not going to hate on you for driving your Yugo


----------



## DaBomb77766

Quote: 





travisg said:


> Just because you have a spec doesn't mean it can't be improved upon. A automobile has a certain spec. An engine or power source,some way to control it and a way for it to move under it's own power,etc,etc. So why does Ferrari or Porsche or Aston Martin bother making any changes to that spec? Why try to improve on a Yugo? Surely a Yugo is an automobile just like an Aston Martin is. But I would like to drive the Aston Martin because they improve on the spec,by using superior materials and build quality. But hey that's just me. To each his own. I'm not going to hate on you for driving your Yugo


 


  The only "specifications" that are needed for automobile production are safety and fuel consumption/emissions ones.  Other than that you can do whatever the hell you want with it.  On the other hand, the spec for USB cables is pretty strict.  You can't really get much "better," since it has to be within the acceptable range for it to be considered "USB."  It would be like having a specification that limited the material you could make the engine block out of, the thickness of gaskets used and the production tolerances for moving parts.  Cars simply do not have regulations like this, whereas USB does.


----------



## tmars78

Quote: 





uelover said:


> @USG: Is there a mac equivalent of Audio DiffMaker? I have no mics with me either. Let me see what I can do about it.
> 
> 
> @Prog Rock Man: I don't think B would be a plausible answer unless a whole chunk of data got corrupted/lost. I guess when we transfer data from our comp to an external harddrive with any USB cables, we are safe because there is error correction but I won't actually expect the error rate to be so large if not the bulk of time will be allocated for error correction instead of transfer.
> ...


 

 This is where confirmation bias comes in. If you spend almost $100 for a .5 meter cable, you are going to expect it to perform better than the cable its replacing, therefore, you are going to, more than likely, get an improvement. The thing is, everyone who says they hear a difference, acts like their mind and ears are infallible. That is soooooo far from the truth. The human mind is one of the easiest things to fool.


----------



## travisg

The argument is not the USB spec,but the implementation of said spec.


----------



## travisg

dabomb77766 said:


> The only "specifications" that are needed for automobile production are safety and fuel consumption/emissions ones.  Other than that you can do whatever the hell you want with it.  On the other hand, the spec for USB cables is pretty strict.  You can't really get much "better," since it has to be within the acceptable range for it to be considered "USB."  It would be like having a specification that limited the material you could make the engine block out of, the thickness of gaskets used and the production tolerances for moving parts.  Cars simply do not have regulations like this, whereas USB does.


 
But yet they continue to make cars get better fuel milage and that are more safe.


----------



## tmars78

Quote: 





travisg said:


> The argument is not the USB spec,but the implementation of said spec.


 


  Yes, I am fully aware of this. And as Dabomb said, this spec is strict. It is strict to ensure that the cable functions as it is supposed to. Which means, its going to work, or its not going to work. And if all cables are built to this spec, they are going to perform the same. We know all there is to know about electrical properties, and have for years and years. What you are saying, is that cable companies have found something else that is undiscovered, but they have no means of proving this unknown property. That is quite a stretch. I mean if you found some new property, and could prove it, why wouldn't you? You could completely corner the market, put all of these other companies out of business, and be quite the billionaire.


----------



## DaBomb77766

Quote: 





travisg said:


> The argument is not the USB spec,but the implementation of said spec.


 


  Indeed, but when it comes to data transmission cables, the spec is fairly strict.  And still, as I said, comparing to cars simply isn't a good comparison.  I think a better comparison would be to something like NASCAR or F1.  They have specifications the manufacturers must meet.  Very strict manufacturing thresholds, and restrictions and standards for nearly every aspect of the racecar.  While manufacturers can, in fact, do better than others within the spec, there's a certain limit to what they can do.  They can, however, sometimes find a loophole in the rules to extract more performance out of their racecar - but that isn't something that applies so much to USB.

 But I digress.  USB is USB.  My point from earlier still seems to stand - that is, you can't expect a cable to shuffle the digital bits around in such a way to actually improve or change only one part of the audio spectrum.  To you, or anybody else, looking at the digital bitstream is meaningless.  Changing random bits around due to errors will affect everything at random, not just one part of the spectrum.


----------



## travisg

All I'm saying is something can uphold a specification and still improve upon it. I don't think there is some USB police out there that forces every company to make a cheap sounding cable because that's all the spec demands.


----------



## tmars78

Quote: 





travisg said:


> All I'm saying is something can uphold a specification and still improve upon it. I don't think there is some USB police out there that forces every company to make a cheap sounding cable because that's all the spec demands.


 


  Umm...actually, there is. And if your cable doesn't meet this spec, you cannot use the USB logo. 
   
http://www.usb.org/developers


----------



## travisg

Havent had this much fun on a thread in a while. I'm done for tonight. Wife says come to bed


----------



## The Pell

I just want to see someone do something about it (And post it in the correct place).


----------



## vandaven

Quote: 





travisg said:


> Just because you have a spec doesn't mean it can't be improved upon. A automobile has a certain spec. An engine or power source,some way to control it and a way for it to move under it's own power,etc,etc. So why does Ferrari or Porsche or Aston Martin bother making any changes to that spec? Why try to improve on a Yugo? Surely a Yugo is an automobile just like an Aston Martin is. But I would like to drive the Aston Martin because they improve on the spec,by using superior materials and build quality. But hey that's just me. To each his own. I'm not going to hate on you for driving your Yugo


 
  Please leave completely different (analog) technology like cars (with internal combustion engines) out of this discussion, it doesn't match the topic.
   
  USB technology is not even equal to "clocked" digital signals like S/PDiF or AES/EBU as it is just a stream of data that is turned into a time discrete digital or analog signal via the DAC inside your USB interface.


----------



## svyr

heh we could get it moved to the sound sci forum


----------



## 00940

Quote: 





vandaven said:


> First off, this is a very entertaining thread.
> 
> As we all know, in most cases, the USB controller of the computer is not directly inside the USB port.
> 
> ...


 

 Some good questions here regarding computers:
   
  - there are desktop computers or laptops with widely different performances and it's almost impossible to know which are the better ones without doing some tests. Some factors:
   
  * The quality of the computer power supply. It's not a question of power but of how clean it is. A noisy PS can either directly inject LF noise into devices attached to it (so did my previous compaq laptop) or higher frequency noise can affect the proper operation of the USB controllers or of the IC inside an attached device (as mentionned earlier, Paul Miller was able to measure jitter on a USB audio connection jumping from 300 ps to 3ns depending on whether or not the laptop was operated on battery or switchmode PS).
  * The quality of the USB controllers and chips surrounding them. Not all parts are created equal, some simply have better performance. Clock generators and the like range from very good to quite poor.
  * The hardware implementation of the USB controllers. Depending on pcb layout, decoupling and so on, they'll be more or less vulnerable to unwanted interaction.
  * The structure of the motherboard, the code attached to it, the OS, the software layer... For exemple, depending on the priority granted to USB processes by your system, you can have data drop out.
   
  Funny thing is, you could have ports on the same computer with various levels of performances. Still, considering all the potential things that can go wrong, it is extremely likely that the problems coming from the computer itself are much bigger than any problems a cable could induce in USB audio transfers. On the other hand, there is also little a cable could do to fix those problems.
   
  - The effects through which cables can in theory make a difference (mostly jitter and power supply corruption) are quite small. Admitting for a moment that they are audible, the distortion they would induce would probably be drowned in the self produced distortions of a cheap device.
   
   
  Quote: 





vandaven said:


> USB technology is not even equal to "clocked" digital signals like S/PDiF or AES/EBU as it is just a stream of data that is turned into a time discrete digital or analog signal via the DAC inside your USB interface.


 

 While not "equal" to spdif, the most common USB audio transfer protocol (adaptive) shares the same fundamental problem of recovering the system clock from a data stream. It is not by chance that TI used the same SPACT audio clock recovery system for both USB and spdif receivers.


----------



## Prog Rock Man

Quote: 





travisg said:


> If you have never tried an audiophile grade USB cable in your system and would rather just say that it makes no difference because you like to spit out digital specs and hyperbole. Please please Shut-up! You do not have the right to speak. If you have tried a superior grade USB cable and found it to be no better than your Walmart cable, by all means continue.


 

 I bought an Oehlbach USB with super dooper claims and a ferrite core. No matter how much I listened I could not make out a difference between it and another stock cable that came with a printer or whatever.
   
  You do have the right to speak if you have knowledge of exactly how USB cables can/cannot affect sound. You have the right to ask questions about the same and put forward your own theory. Don't try and supress knowledge and discussion. It is bad enough blind testing is banned to Sound Science.


----------



## Prog Rock Man

Quote: 





jackmccabe said:


> I suggest you search with google for blind test's.
> Also cable manufacturers cannot be sued as they are very careful about what they say; they never say that they are better than another cable and they also say things like "Clear and open highs, elegant midrange textures" which could apply to any usb cable as you would struggle to produce unclear highs or untextured mids.


 

 True, they are allowed 'puffery'. Russ Andrews and Kimber Kable fell foul of the Advertising Standards Agency when they did make a measureable claim about RFI rejection of their cables. The ASA pointed out that they could not show a connection between RFI rejection and improved sound quality, they could only insinuate such. Smaller bespoke cable makers need to be careful what they say as the costs of an ASA fine and associated legal expenses could cripple them, and the big ones such as Belden are too canny to make any claims they can be held to account for.
   
  This is what Kimber say about their USB cable
   
  "The popular USB interface now plays an important role in both consumer and professional audio and video. Audio devices that utilize USB data modes require reliable transfer of data to operate properly. To address this need Kimber Kable created high performance USB type cables. Our Mini BUS and B BUS cables utilize copper conductors with an unusually thick (6.1%) silver plating to enhance conductivity and signal support. The largest gauge conductors possible under USB specification are used for both the signal and power conductors. A high performance nitrogen-infused polyethylene (PE) dielectric is used on the signal conductors to maximize signal integrity. Ferrite noise reduction beads are used on both ends of the cable to prevent interference of the delicate data stream. The Mini BUS is terminated with a USB A type connector on one end and a mini B type connector on the other. The B BUS is terminated with a USB A type connector on one end to a USB B type connector on the opposite end."
   
  A bit of puffery with 'high performance', 'unusually thick', 'maximise signal integrity' and 'delicate data stream' and nothing measureable or testable. I wonder why????


----------



## DaBomb77766

Quote: 





prog rock man said:


> I bought an Oehlbach USB with super dooper claims and a ferrite core. No matter how much I listened I could not make out a difference between it and another stock cable that came with a printer or whatever.
> 
> You do have the right to speak if you have knowledge of exactly how USB cables can/cannot affect sound. You have the right to ask questions about the same and put forward your own theory. Don't try and supress knowledge and discussion. It is bad enough blind testing is banned to Sound Science.


 


  I have a whole bunch of USB cables with a ferrite core!  I've heard that ones with ferrite cores can actually help with various issues the Fiio E7's DAC sometimes has.  Forgot exactly what these are though.  I've never been very clear over exactly what ferrite cores even do, Wikipedia wasn't awfully helpful on this for me.


----------



## Prog Rock Man

I got one with a ferrite core as I had noticed most of the wires for my laptops and printers have cores on their power and other cables. I figured that if Dell, Sony and HP feel they are of use then they must be. Otherwise why go to the expense?
   
  My stock USB does not have a ferrite core and again, it sounds no different to the Oehlbach, which now lives in a bag with other cables, in case I need one that long with the mini B connection it has at one end.


----------



## DaBomb77766

Quote: 





prog rock man said:


> I got one with a ferrite core as I had noticed most of the wires for my laptops and printers have cores on their power and other cables. I figured that if Dell, Sony and HP feel they are of use then they must be. Otherwise why go to the expense?
> 
> My stock USB does not have a ferrite core and again, it sounds no different to the Oehlbach, which now lives in a bag with other cables, in case I need one that long with the mini B connection it has at one end.


 


  It would be pretty silly to use an audiophile cable for, say, connecting your camera to your computer though, since I highly doubt they're as durable as a good stock one.  Not to mention they look kind of really out of place next to all of the other cables.  They look like something that should be inside the computer, not outside.


----------



## 00940

Quote: 





dabomb77766 said:


> I have a whole bunch of USB cables with a ferrite core!  I've heard that ones with ferrite cores can actually help with various issues the Fiio E7's DAC sometimes has.  Forgot exactly what these are though.  I've never been very clear over exactly what ferrite cores even do, Wikipedia wasn't awfully helpful on this for me.


 

 To put it simply, the ferrite bead increases the impedance of the transmission line at high frequencies. It thus reduces the amplitudes of higher frequency noise. Think of it as a filter.
   
  What is unclear in this wikipedia entry ? http://en.wikipedia.org/wiki/Ferrite_bead


----------



## DaBomb77766

Quote: 





00940 said:


> To put it simply, the ferrite bead increases the impedance of the transmission line at high frequencies. It thus reduces the amplitudes of higher frequency noise. Think of it as a filter.
> 
> What is unclear in this wikipedia entry ? http://en.wikipedia.org/wiki/Ferrite_bead


 

 http://en.wikipedia.org/wiki/Ferrite_core
   
  Oh, I was looking at that article there.  A little more ambiguous, but I guess it's a totally different thing in that case.  Thanks though, I didn't see that other article.


----------



## pompon

Just using USB HUB (with power supply) near your dac.
   
  The data coming from the computer is completely restored inside the hub and the noisy current from the computer is not used at all.


----------



## vandaven

Even though it might seem inappropriate, I just add the results of my little experiment to this thread, if somebody wants to start a new one or move this thread, please go ahead.
   
  I decided to buy a usb cable for the test that sells for about 50 € (70 US$), which seems to be the better of the two "budget" solutions that a notorious cable manufacturer offers.
  According to a review in a german hifi webzine, that range of usb cables give the listener an improved listening experience that scales with the price. Thus, I supposed the product, while not in the 500 - 2500+ US$ range, should at least give some minimal sound improvement in comparison to a obviously super-cheap, thin, no-name USB printer cable (let's call it "grey") that is at least twice the length of the quality cable. At least the quality cable is red (let's call it "red" from now on) and looks like a quality cable to me. 
   
  Back at studio, I connected the "red" to my Digidesign Mbox2, which is a USB audio interface that might not live up to my highest sonic expectations anymore, but it was quite helpful for portable Pro Tools edit work in the past. The plan was to send a 48 kHz 24 bit sound file out of Logic Pro (audio software) to the interface, send it out via S/PDIF, re-record it in Logic via S/PDIF in, and repeat the same procedure with the "grey" cable. Phase-inverting one of the two recordings and summing it up with the other should display the sound differences between the way those two cables transport the audio data, as the only (audible) signal left after this process should be the improved quality "red" adds to the sound.
   
  To put a long story short, I was able to achieve a full phase cancellation between the "grey" and "red" signal, even *normalizing* the (presumably empty) audio files did not lead to any noticeable result. Pure fact: "Red" is in no way superior to "grey", but looks a lot better, so it might be worth the extra money. Even though "red" is not the most expensive USB cable on the market, it is believed to improve the sound quality, but alas it doesn't. People who spent thousands on a single USB cable will still insist on the improvement in listening quality.
   
  I guess it's nice to believe in magic.


----------



## jackmccabe

This thread really should have been put in the sound science forum, as we cannot discuss that which cannot be named (hint begins with "b" and ends with "lind tests")


----------



## 00940

Not sure I understand your chain for the test ? Does the signal ever leave the digital domain ? 
   
  Theoretically, I wouldn't expect differences without involving a DAC in the chain (and thus an ADC).


----------



## Prog Rock Man

Great test vandaven. All you need to do is show that no matter what USB cable you use, the resulting signal is the same and you show any audible change is not caused by the cable. Then, even if you do find a difference, you need to show it is audible. That invloves the thing that jackmccabe alludes to and should really stop......


----------



## vandaven

Quote: 





00940 said:


> Not sure I understand your chain for the test ? Does the signal ever leave the digital domain ?
> 
> Theoretically, I wouldn't expect differences without involving a DAC in the chain (and thus an ADC).


 

 While the signal doesn't leave the digital domain, it's nonetheless converted from a usb stream to a discrete-time signal, clocked by the usb interface. If there would be any difference in the signals transported by the two usb cables, there would be an obvious difference in regards to the re-recorded signals.


----------



## upstateguy

Quote: 





vandaven said:


> Even though it might seem inappropriate, I just add the results of my little experiment to this thread, if somebody wants to start a new one or move this thread, please go ahead.
> 
> I decided to buy a usb cable for the test that sells for about 50 € (70 US$), which seems to be the better of the two "budget" solutions that a notorious cable manufacturer offers.
> According to a review in a german hifi webzine, that range of usb cables give the listener an improved listening experience that scales with the price. Thus, I supposed the product, while not in the 500 - 2500+ US$ range, should at least give some minimal sound improvement in comparison to a obviously super-cheap, thin, no-name USB printer cable (let's call it "grey") that is at least twice the length of the quality cable. At least the quality cable is red (let's call it "red" from now on) and looks like a quality cable to me.
> ...


 

 Good test.  As a matter of fact a very clever test. 
   
  But let me understand what you did. 
   
  You sent the test tone from your computer to the MBox via usb?
  You connected the spdif out of the MBox to spdif in on your computer, where it was decoded and you recorded the results? (I'm not familar with the MBox.)
   
  Now try it with some music.  See if you can null them out again.  Careful not to disturb the volume. Record them as flacs and post on one of the sharing sites so we can hear them too.
   
   
  Some things you might hear:
   
  1- your equipment isn't resolving enough.
  2- red wasn't really an audiophile cable.
  3- didn't try it with music
  4- there was also a coaxial cable of unknown quality in the loop


----------



## upstateguy

Quote: 





vandaven said:


> While the signal doesn't leave the digital domain, it's nonetheless converted from a usb stream to a discrete-time signal, clocked by the usb interface. If there would be any difference in the signals transported by the two usb cables, there would be an obvious difference in regards to the re-recorded signals.


 


  I think I understand now.....  you were testing the integrity of the digital signal.


----------



## upstateguy

Quote: 





prog rock man said:


> Great test vandaven. All you need to do is show that no matter what USB cable you use, the resulting signal is the same and you show any audible change is not caused by the cable. Then, even if you do find a difference, *you need to show it is audible*. That invloves the thing that jackmccabe alludes to and should really stop......


 


  He could record from the line out back into his computer and invert from there.....


----------



## vandaven

Quote: 





upstateguy said:


> Good test.  As a matter of fact a very clever test.
> 
> But let me understand what you did.
> 
> ...


 

 No test tone was sent, I used complex waveforms (in fact, Jazz music, to be more precise, a piece from a David Sanborn album).
   
  The S/PDIF in of my computer wasn't used, signal went from S/PDIF Mbox2 out -> S/PDIF Mbox2 in, USB used both ways.
   
  re: 1. - I do not know what you mean by "resolving", as the signal never leaves the digital domain.
  re: 2. - "red" is marketed as audiophile cable, reported in the review to "improve the listening experience".
  re: 3. - explained
  re: 4. - The coaxial cable is a rather expensive, quality cable used in studios all over the world, even IF the coaxial cable would be of lower quality, chances are that any "degradation" will degrade both signals the same way, so there still would be a difference between "red" and "grey"


----------



## upstateguy

Quote: 





vandaven said:


> No test tone was sent, I used complex waveforms (in fact, Jazz music, to be more precise, a piece from David Sanborn's new album).
> 
> The S/PDIF in of my computer wasn't used, signal went from S/PDIF Mbox2 out -> S/PDIF Mbox2 in, USB used both ways.
> 
> ...


 


  That's even more interesting than I thought it was.  You used usb both ways and the signals nulled out. Yes?


----------



## jackmccabe

Prog Rock Man, I try and control myself


----------



## vandaven

Quote: 





upstateguy said:


> That's even more interesting than I thought it was.  You used usb both ways and the signals nulled out. Yes?


 

 Yes. The Digidesign Mbox2 might not be the greatest converter on the planet (in regards to the other pro audio stuff that's around), but it's good enough for an all-digital test to show that there is no difference between "grey" and "red" apart from fancy looks and price. 
   
  In case somebody still wants to comment on "resolving", please mind that it's 48 kHz 24 bit all the way.


----------



## Prog Rock Man

Quote: 





jackmccabe said:


> Prog Rock Man, I try and control myself


 

 A good substitute to shhhh is the null test. That basically means you pass signals down different cables, record them and then invert one and put them together. If you are left with silence, there is no difference. If you left with some sort of signal, but you cannot hear it, there is a difference, but it is inaudible.


----------



## jackmccabe

Wow, thanks I had never heard of that test.


----------



## vandaven

Quote: 





prog rock man said:


> A good substitute to shhhh is the null test. That basically means you pass signals down different cables, record them and then invert one and put them together. If you are left with silence, there is no difference. If you left with some sort of signal, but you cannot hear it, there is a difference, but it is inaudible.


 

 Thanks for understanding the null test. I might want to add that even inaudible signals (as in: signals that we can't hear but that show up on the analyzer or the meter) can make a difference to a listening experience as they will modulate the audible part and thus change it. If you null / compare 96 kHz 24 bit recordings with, let's say, a downsampled 48 kHz 24 bit version of the same track properly, the null result will be a complete "audible" phase cancellation, thus, you won't hear a thing (unless you have the hearing of a dog). But you will see a signal on the meter. That is the signal that will modulate the signal in the audible range and give you the fine difference between 96/24 and 48/24 (44.1/24).


----------



## 00940

Quote: 





vandaven said:


> While the signal doesn't leave the digital domain, it's nonetheless converted from a usb stream to a discrete-time signal, clocked by the usb interface. If there would be any difference in the signals transported by the two usb cables, there would be an obvious difference in regards to the re-recorded signals.


 

 If there was a difference in data, there certainly would be a difference in the re-recorded signals. However, differences in noise levels, interferences or jitter wouldn't create differences with your test setup. The fact that it is clocked by the usb interface doesn't matter as long as you get all your bits in the correct order. In other words, the quality of the clock recovered from the USB interface can be really good or completly awful and you would still get the same recovered signal.


----------



## vandaven

Quote: 





00940 said:


> If there was a difference in data, there certainly would be a difference in the re-recorded signals. However, differences in noise levels, interferences or jitter wouldn't create differences with your test setup. The fact that it is clocked by the usb interface doesn't matter as long as you get all your bits in the correct order. In other words, the quality of the clock recovered from the USB interface can be really good or completly awful and you would still get the same recovered signal.


 

 A difference in jitter would definitely be recognized, because the amount of jitter is defined by how the USB stream is received by the DAC. I can't seem to understand how noise levels should, in any way, interfere when we have coherent, 100% similar signals. If one of the usb streams would include interference, "noise" or "jitter", "red" and "grey" wouldn't be identical. 
   
  I think you are mixing up problems with the transportation of time-discrete (S/PDiF, AES/EBU) digital signals, which are totally different to the USB stream feeding the audio interface. This is one of the reasons why a hardware "buffer" exists. Of course, when talking about analog signals, you are totally right with induced noise, interferences etc.
   
  These terms also come into play when we're talking about the quality of a DAC and the related analog output stage, but definitely not in regards to USB streams.


----------



## Currawong

My only caution with these tests would be: I'd want the recording equipment to have an equal, or lower THD overall than the equipment I am measuring, otherwise I'd be wasting my time.  I'm sure I could do the same tests with my computer, but I'm also quite sure that its analogue audio system has inferior specifications compared to my audio gear.


----------



## jackmccabe

I will perform a few of these with my emu 1820m when I can.


----------



## vandaven

Quote: 





currawong said:


> My only caution with these tests would be: I'd want the recording equipment to have an equal, or lower THD overall than the equipment I am measuring, otherwise I'd be wasting my time.  I'm sure I could do the same tests with my computer, but I'm also quite sure that its analogue audio system has inferior specifications compared to my audio gear.


 

 In the test I did, the THD equals the THD that is "delivered" with the recording, as it never passes through an analog circuitry. 
   
  What was questioned in this thread related to a person asking "why an 'audiophile' USB cable would improve the sound quality". As this question also yielded some importance to me, I asked myself how validation could be found, went out, bought a cable, and checked it in a situation in which the only critical part is the USB cable, not the converters or any analog stage within the signal chain. I performed this test with the "red" cable recommended in a review and by the sales person in the HiFi shop. 
   
  I also want to exaggerate that I went into this review unbiased. I also want to point out that I am absolutely positive on the fact that there are sound differences between certain converters, amplifiers, and cables for time-discrete digital and analog audio connections.
   
  I am sorry that the outcome of my little test might not approve the "group opinion" about esoteric USB cables, and maybe the "red", even though advertised as improving the listening experience, does not work as such. Maybe your precious USB cable makes a difference, and even if it would only make a difference to your interpretation of sound, it's a personal win.
   
  I am here because I like to listen to great music recordings in the best possible way my budget allows me to, and I just wanted to apply my experiences to this thread, which is coming out of an empirical (and re-create-able) little experiment. I would be more than happy to report that there are differences between "red" and "grey", and then go into further investigation.


----------



## vandaven

Just to explain how "inverse summing" works inside a digital audio workstation, I prepared a couple of spectral analysis jpeg uploads:
   
  these are:
   
  1. original 96 kHz 24 bit material:
   

   
  2. original 96 kHz 24 bit material converted to 48 kHz 24 bit:
   

   
  3. original 96 kHz 24 bit material minus (= inverse summing) 48 kHz 24 bit material (upsampled to 96 kHz again to perform the summation:
   

   
  4. original (but different to 1. / 2. / 3.) source audio material for "red" vs. "grey":
   

   
  5. "red" minus "grey"


----------



## 00940

Quote: 





vandaven said:


> A difference in jitter would definitely be recognized, because the amount of jitter is defined by how the USB stream is received by the DAC. I can't seem to understand how noise levels should, in any way, interfere when we have coherent, 100% similar signals. If one of the usb streams would include interference, "noise" or "jitter", "red" and "grey" wouldn't be identical.
> 
> I think you are mixing up problems with the transportation of time-discrete (S/PDiF, AES/EBU) digital signals, which are totally different to the USB stream feeding the audio interface. This is one of the reasons why a hardware "buffer" exists. Of course, when talking about analog signals, you are totally right with induced noise, interferences etc.
> 
> These terms also come into play when we're talking about the quality of a DAC and the related analog output stage, but definitely not in regards to USB streams.


 
   
  1/ Did you forget that you have no DAC in your fully digital chain ? I maintain that a difference in jitter in the audio clock built upon the USB stream wouldn't be recognized. Think about it again: the USB receiver receives the data stream, converts it to spdif (in terms of bits, this conversion can be absolutly bit-perfect, it depends on your drivers and hardware) and then sends it out at a speed derivated from a clock recovered through a PLL  from the timing of the packets of the USB stream (in isochronous and adaptive modes). Two cases now:
  - If the spdif stream goes into a digital input and is kept in the digital realm, the quality of that clock is pretty much irrelevant, as long as we can read all the bits in the right order and put them in a big buffer (your HDD in the end). Which is what you demonstrated.
  - If it goes into a spdif to I2S receiver and the I2S into a DAC IC (typical use), the quality of that clock will in turn affect the quality of the clock recovered by the spdif receiver and thus finally the digital to analog conversion.
   
  The same reasoning applies if the USB receiver is linked straight to a DAC, minus the passage through SPDIF. If the USB audio stream is in asynchronous mode however, then the jitter of the recovered clock is reduced to only the inherent jitter of the clock inside the usb peripheral and the USB cable cannot influence it.
   
  2/ As for noise and interferences: a full digital system like you've got is quite robust under that respect. You'd need extreme levels to get an error. But a mixed signal system like a DAC is much more sensitive to noise. Don't forget that your USB cable is a two functions cable: data and power. If external hf interferences can get into the cable ground or power lines, if 1Khz spikes can couple from the data lines to the same lines, etc., then this noise in the power lines will affect (to an extent defined by the design and implementation of the USB device) the proper operation of the DAC IC and of the following analog stage. Your test cannot account for those factors.
   
  3/ Actually, you don't have much in terms of hardware buffer in your typical USB audio playback devices. Not much more than in SPDIF receivers. Thank accountants who don't like expensive die area tied up for buffers and engineers who don't like latency for that.


----------



## DaBomb77766

A great test you did there!  Now, I wonder how this would work if the audio was converted to analog, then recorded again with professional recording equipment?  I'm guessing it'd be exactly the same, but I think the test should be done regardless.  Still, this doesn't seem like it belongs in the cable forum anymore, but I guess that's up to the mods.


----------



## Mambosenior

Man, all this testing just wrinkles my nose hairs! No matter the facts, I am keeping my fancy USB as a plain grey cable (without pin-stripes, even) would just simply destroy the color scheme of my audio system.
	

	
	
		
		

		
			




   
  (...and from the great beyond, “Dandy” Don Meredith is heard singing: “Turn Off The Lights, The Party’s Over.”)


----------



## lunarmouse

Quote: 





vandaven said:


> No test tone was sent, I used complex waveforms (in fact, Jazz music, to be more precise, a piece from a David Sanborn album).
> 
> The S/PDIF in of my computer wasn't used, signal went from S/PDIF Mbox2 out -> S/PDIF Mbox2 in, USB used both ways.
> 
> ...


 

 Very interesting experiment!
  I could somehow understand why people want to purchase seemingly way-overpriced digital cables (USB, HDMI), psychologically, because they might think the super-cheap no-name cable simply does not match their $$$$$ investment in the system. It seems a placebo effect to me. You FEEL that the high-end USB cables make a difference because you KNOW they carry a big price tag. Maybe a blind A-B test is the most reliable and believing.


----------



## Satellite_6

Tests on head-fi? Have I wandered onto the wrong site? Good stuff.


----------



## Roller

Well, I'll keep my thoughts that aftermarket USB cables do make a difference in sound quality, not on improving sound itself but rather eliminating issues like crackling and drop-outs, for which the (double) ferrites do seem to work wonders. So I find that said cables work for correction, not improvement. But it's merely my opinion, and it's what works for me and what I've seen for a fact, everyone else is entitled to their opinion.


----------



## vandaven

Alright, now you really made me go down to the control room and do it DAC - ADC.
   
  The reason why I wanted to avoid this is because it might be a bit misleading for some people, but I guess the measurements speak for themselves. Please do not forget that this is happening in the analog realm as well as in the digital, and while the digital realm can be sample-precise with a complete phase cancellation as mentioned above, a summed peak level of, let's say, -55 to -62 dB can already be considered as "phase cancellation". This means: In the analog realm, there will always remain a tiny bit of very low audible information while in the digital realm, nothing will remain in the same process. 
   
  To demonstrate that neither cheapo USB cable "grey" nor "improved listening experience" cable "red" hold positive or negative aspects against each other, I now did the following:
   
  a. Connect high quality analog audio cable to LINE OUT of the audio interface
  b. Connect other end of high quality analog cable to LINE IN of the audio interface
  c. Connect computer & audio interface via USB cable "red"
  d. Play back a complex waveform (Jazz Music, David Sanborn - what a great artist) through DAC, re-record at the same time via ADC, repeat with "grey"
  e. Repeat again with "red" to demonstrate slight deviation of converters and analog circuitry
  f. compare all recordings via phase inverse summing 
   
  This leads to the following results via spectral analysis:
   
  1. "red" take 01 minus "grey"
   

   
  2. "red" take 02 minus grey
   

   
  3. "red" take 01 minus "red" take 02
   

   
   
  My conclusion:
   
  - Neither "red" nor "grey" are the better USB audio cable, red still looks better, grey is still exactly double as long and way thinner than "red".
   
  - The Mbox2 is really not the best audio interface in the world, but I won't compare it to my Nuforce (in the sense of a review).
   
  Please stop thinking that your computer or the USB stream clocks your DAC - I'll give you an example: I can set my Nuforce uDAC2 to any sample rate I want and it will still play back the music without any drops, clicks or pops, for example, I can put on a 96 kHz 24 bit WAV, switch the NuForce to 44.1 kHz and 16 bit and have the unique experience how it would sound back in the 90s on CD. Try the same thing with a 48 kHz 24 bit DAT via digital S/PDIF connected to a device that only talks 44.1 kHz 16 bit and experience what real digital errors sound like (for example, clicks & plops @ 0 dBFS).
   
  Cheers!


----------



## vandaven

Quote: 





dabomb77766 said:


> A great test you did there!  Now, I wonder how this would work if the audio was converted to analog, then recorded again with professional recording equipment?  I'm guessing it'd be exactly the same, but I think the test should be done regardless.  Still, this doesn't seem like it belongs in the cable forum anymore, but I guess that's up to the mods.


 

 Quote:


lunarmouse said:


> Very interesting experiment!
> I could somehow understand why people want to purchase seemingly way-overpriced digital cables (USB, HDMI), psychologically, because they might think the super-cheap no-name cable simply does not match their $$$$$ investment in the system. It seems a placebo effect to me. You FEEL that the high-end USB cables make a difference because you KNOW they carry a big price tag. Maybe a blind A-B test is the most reliable and believing.


 

 Yep, I quickly did that test. Blind A-B ain't sufficient, as chances are always 50-50. I know people who won in the lottery (not me though). One could get it "wrong" or "right" by pure luck, at least in regards to "red" 
	

	
	
		
		

		
		
	


	




.


----------



## Currawong

Please remember that DBT/blind test discussion isn't permitted in the cable forum (due to the result inevitably being that sane conversation becomes impossible soon after it is brought up). 

Back to the discussion, I can only imagine a different USB cable being of benefit where the receiving DAC has a digital input circuit that is sensitive to differences in the waveform of the signal it receives. However, in such a case (and for myself recently) I'm far more inclined either to spend money on a better DAC without these issues or a high quality USB to S/PDIF converter. 

Vandaven: Good on you for taking some measurements. My post before was to point out that people here often tend to have an attitude that a single measurement can be all-conclusive in what it shows and don't consider (as a genuine scientist would) all the possible factors that may influence the results.


----------



## 00940

First, thanks for taking the time of doing another round of test. You've nicely shown that any artifact due to the cable in your system is under 80db or so (having a quick look at the specs of your equipment) and thus likely unaudible.
  
  Quote: 





> Originally Posted by *vandaven* /img/forum/go_quote.gif
> 
> Please stop thinking that your computer or the USB stream clocks your DAC - I'll give you an example: I can set my Nuforce uDAC2 to any sample rate I want and it will still play back the music without any drops, clicks or pops, for example, I can put on a 96 kHz 24 bit WAV, switch the NuForce to 44.1 kHz and 16 bit and have the unique experience how it would sound back in the 90s on CD. Try the same thing with a 48 kHz 24 bit DAT via digital S/PDIF connected to a device that only talks 44.1 kHz 16 bit and experience what real digital errors sound like (for example, clicks & plops @ 0 dBFS).


 
   
  What you suggest doesn't prove anything; it depends on your whole DAC implementation. According to the litterature I've found on the uDAC2, it includes a sample rate converter (burried in the ESS dac chip they use, it's their "jitter reduction" feature). The USB receiver gets the 24/96 USB stream from the computer, outputs a 24/96 I2S stream and the SRC transforms it into I2S 16/44.1 before feeding the DAC section. If the sample rate converter is asynchronous (very likely as it's the current fashion), the clock feeding the DAC doesn't have anything left to do with the USB stream. I can do the same with SPDIF, ASRC are wonderful little beasts.
  
  If you take a simpler DAC however, you don't have that SRC. I should know, I've built USB DAC based on both clocking schemes (and not from kits). Unlike SPDIF, you have many different ways to implement USB audio.
   
  Please read http://www.audioasylum.com/forums/pcaudio/messages/7719.html and http://www.eetimes.com/design/audio-design/4009467/The-D-A-diaries-A-personal-memoir-of-engineering-heartache-and-triumph
   
  To put things in perspective: a commonly measured jitter figure for the audio clock of the widespread PCM2704-7 serie of adaptive usb receivers is around 3ns  (it seems it could go down to 300ps when special care in implementation is taken).


----------



## lunarmouse

Sorry didn't notice it in the header. I just mean... it's seems more like a psychological issue than a technical one to me.
  Quote: 





currawong said:


> Please remember that DBT/blind test discussion isn't permitted in the cable forum (due to the result inevitably being that sane conversation becomes impossible soon after it is brought up).


----------



## Prog Rock Man

Quote: 





00940 said:


> First, thanks for taking the time of doing another round of test. You've nicely shown that any artifact due to the cable in your system is under 80db or so (having a quick look at the specs of your equipment) and thus likely unaudible.
> 
> 
> What you suggest doesn't prove anything; it depends on your whole DAC implementation. According to the litterature I've found on the uDAC2, it includes a sample rate converter (burried in the ESS dac chip they use, it's their "jitter reduction" feature). The USB receiver gets the 24/96 USB stream from the computer, outputs a 24/96 I2S stream and the SRC transforms it into I2S 16/44.1 before feeding the DAC section. If the sample rate converter is asynchronous (very likely as it's the current fashion), the clock feeding the DAC doesn't have anything left to do with the USB stream. I can do the same with SPDIF, ASRC are wonderful little beasts.
> ...


 



 This is about the alleged effects of the cable, you are talking about the sender and receiver and how they interact. By criticising the cable you are shooting the messenger who has nothing to do with what else is going on.


----------



## 00940

Quote: 





prog rock man said:


> This is about the alleged effects of the cable, you are talking about the sender and receiver and how they interact. By criticising the cable you are shooting the messenger who has nothing to do with what else is going on.


 

 Poor messenger, should I present it my excuses ? 
	

	
	
		
		

		
			




   
  Sorry but you obviously have a very limited understanding of how the sender and receiver interacts and how the cable fits in this interaction. What is your proof that the "messenger has nothing to do with what else is going on", besides your prejudices ? You'd better present your case seriously to go against the word of someone as obsessed as Paul Miller about measurements...
   
  Furthermore, tests are only valid if you have a complete understanding of the whole chain inside the devices under test (which is what my post you quoted was about, to be accurate). Otherwise, you just shoot in the dark.
   
  You don't seem to understand that I'm not criticizing the cable, I've stated aplenty that I don't believe in USB cables making an audible differences. However, I'm more than willing to correct people who don't know anything about the topic and present flawed reasons on why the cables don't make a difference.


----------



## vandaven

Quote: 





00940 said:


> First, thanks for taking the time of doing another round of test. You've nicely shown that any artifact due to the cable in your system is under 80db or so (having a quick look at the specs of your equipment) and thus likely unaudible.
> 
> 
> What you suggest doesn't prove anything; it depends on your whole DAC implementation. According to the litterature I've found on the uDAC2, it includes a sample rate converter (burried in the ESS dac chip they use, it's their "jitter reduction" feature). The USB receiver gets the 24/96 USB stream from the computer, outputs a 24/96 I2S stream and the SRC transforms it into I2S 16/44.1 before feeding the DAC section. If the sample rate converter is asynchronous (very likely as it's the current fashion), the clock feeding the DAC doesn't have anything left to do with the USB stream. I can do the same with SPDIF, ASRC are wonderful little beasts.
> ...


 
   
  I daresay things have been put into wrong terms here: The "artifacts" you see are not due to the USB cable, nor due to any analog cable used in the process. What you see there is the difference in quantization both at the DAC and ADC stage plus the analog stages that come after the converter. This is why I first did the test simply using S/PDIF, as I expected misinterpretations as the one you wrote. When a (time discrete and finite, meaning with a certain sample rate and bit resolution that can be easily presented via a numerical system) digital signal is converted to the analog domain, it becomes an analog signal (due to the use of up-sampling and reconstruction filters). This reconstructed analog signal theoretically has an infinite resolution. When converting this analog signal back to digital information, it's sampled and quantized again, which, together with build tolerance of the analog parts of the ADC - DAC chain, leads to those artifacts you falsely identified as artifacts due to some cabling. 
   
  I am not an expert on converter design in the analog and digital domain, yet I have the impression that I know how the technology basically works. Converters that are being clocked by the USB stream, as designed / mentioned by you, have never been used by me. Modern analog-digital converters use up-sampling and clocks in the megahertz range to overcome the limitations of the Nyquist point. 
   
  Nonetheless kudos to you for designing and building your own converters, it would be a thrill to hear, test and compare them to designs by Apogee, Metric Halo and RME which are used in studios I know.


----------



## 00940

I think you read too much in my post. I didn't try to say that the visible artifacts are due to the cables. I was just trying to say that, if there were artifacts due to the cables, they're under the noise floor/distortion levels of your test gear (I made a mistake there btw, it's -90db and not -80db for the ADC line input) and cannot be seen or heard.


----------



## Hennyo

Cable quality for audio is not something measurable, I'm sorry, and if you don't like that, I'm also sorry. Please go try one before you burst into flame. If you don't you're denying yourself something special, period.
   
  Why do you think there are such people who would so strongly defend it? Why TRY (HARDER) to debaucherize them?!!?
   
  Go buy a freakin cable, if you find it sounds better, then obviously you've learned. If not, you've got the snakeoil cable. I firmly advise that it you're to try a usb cable try Carbon USB by audioquest as even though I did not stick with this, (and pursued higher up the product line) it was the best bang for buck, and is undeniably _better_, p.l.a.i.n. a.n.d. s.i.m.p.l.e. More detail, much wider soundstage, much more sparkling dynmaics, and very, very, clear vocals and consonants from the lips. If you'd like me to describe it or other cables more I will.
   
  Each cable is manufactured differently, and thus carries data differently. TRY a decent aftermarket out, and _behold._ It is NOT irrational, and it is NOT imaginary. I've demoed over... lets see now. hmmmmm, 6 usb, 4 coax, 2 toslink, and 1 quartz fiber optic. I chose the Coffee audioquest usb as even though the Diamond was amazing, (widely thought greatest/best usb on the market) the coffe was a much better bang for buck.
   
  The average cost of these cables range from $30-750 each. I know what I'm talking about, and I've MADE the effort to travel all over my state just to test the waters / cable theory
  If you don't like it, that's your problem. Signing off this thread, no point in arguing with the more vocal of them. This topic drives me mad because nobodies willing to listen to the only rational out there on this subject: _experience_  
	

	
	
		
		

		
		
	


	




 Sometimes, the guy who's actually tried it is right, go figure.
   
  p.s. Sigh, in conclusion A: Cables make leaps and strides of a difference in any/all systems, no matter which part of the chain. Signal or power (headphone) cable.
   
  B: Each cable does have its own sound signature and presentation of sound, _just like headphones_. It is not measurable or "showable" as some in this thread are so desperately looking for. It is however plainly _hearable_, and is nearly as distinct as swapping headphone to headphone on the same system. Each cable produces a different sound.
   
  And finally: C: Cables make a difference an order of magnitude larger than people are willing to admit. They fine tune your sound and your system based on each cable materials conductivity, dampening, shielding, braiding techniques, Di-electric Biasing system, We're even entering the world of DI-electric Bias systems!
   
  -Hennyo


----------



## Hennyo

Most people spend 10-15% of their system cost on cable, or less. I have found however, that cable is vastly underestimated, and while expensive, can be carried from upgrade to upgrade. I may have gone a little overboard, but 50-60% of my system is cable. That's the evidence - _equilibrium_ cost I have found cables deserve. Leaps and bounds mate, leaps and bounds. My cables each cost just as much as my new HD 650's and Grados did, go figure, I have 925$ of cable for 450$ of headphone. but you know what? It was _COMPLETELY_, worth it, and once you hear the difference, you cannot un-hear it.


----------



## DaBomb77766

Please.  Leave your mysticism out of here.  There's absolutely no way an $800 cable will make a $50 setup sound "better," unless it's simply via placebo effect, which I'm not denying, it definitely exists.  If scientific measurements can't find any difference, there is no difference, plain and simple.  Since you've gone to all the trouble to buy the cables, why don't you try doing a scientific blind test on the sound science board?  That's the only way you're gonna convince me.


----------



## Hennyo

You're blowing things out of proportion. GET A ROOM with somebody who cares about your smear campaign numbers.
   
                                ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  It's silly suggesting blind tests as it's just as clearly pronounced as A to B'ing headphones. You have no experience, you have no room to talk, period. Now please, _please_  quit flaming other peoples hard work and months of observation.


----------



## Hennyo

I just Facepalm at you, no sense in beating a dead horse. If I didn't care about enhancing others sonic experience, I wouldn't be here sharing my experience would I? SO please BACK OFF. And take your HATRED somewhere ELSE.  
	

	
	
		
		

		
		
	


	







  I'm not trying to bring your gear into the quation, but you're also running an HD 595 to begin with: out of a portable sourced Fiio, which is fine dude, I'm trying not to hate. HD 595 was my first phone. But please do not act like a headphone guru. That's all I ask. If you've not sunk the time or the money, or some UBER dedication into the hobby, hearing as much gear as you can reasonably get your hands on, please do not make outrageous claims. It's misleading to the rest of the community if somebody does not speak from their own experience. I'm not here trolling, and I'm not here flaming, I'm sharing an educated opinion, so please BACK OFF with such fervor. If you would like me to describe some of the "placebo" (har-har) effects that recabling concerns, please ask away, and I will assist you in finding what you want to know as best I can... If I have no experience to draw from, I will not say I know something I don't.
   
  I will simply give you my opinion and describe what I have heard. Thank you sir and goodnight.


----------



## DaBomb77766

I'm sorry, but you are both trolling and flaming right now.  I may not have the most expensive gear out there, but that' simply because I cannot afford it.  If I could, I would.  And in fact I would buy more expensive cables just to see if they can make any difference.  Bashing someone for how expensive their gear is isn't very classy.
   
  But it is physically impossible for a USB cable to actually make the kinds of changes to the sound you're suggesting.  This has nothing to do with experience - a digital waveform is completely different from an analog one.  I can see how a cable could perhaps change an analog waveform.  Maybe it has slightly different impedance at different frequencies and actually changes the sound that passes through it.  But if a USB cable changed, in any way, the signal passing through it, it won't be something so clear-cut that you can actually clearly pick out the difference every time.  To the cable, and to anyone looking at the signal, it's just a series of meaningless bits.  There's no change in frequency and no variable amplitudes.  It's all just 1s and 0s in different orders.
   
  I don't care about what you say, it's physically impossible for a cable alone to make real audible differences to a digital bitstream like this.  The only plausible way it could is if it is actively intercepting the signal in a decoder chip and changing the signal to something else.  Other than that the differences will only be in corrupted bits and the like.  It's not like a length of copper or silver will be able to grab the sequence of bits that makes up a high frequency signal then modify it to be "less harsh" or "more effortless."


----------



## Hennyo

Ok, We're not getting anywhere and I'm totally not trying to bring your gear into this. I'm 18 and have lived on my own for three years. I know how hard it is to afford nice things and it would be f&%#%$ up for me to bash you just for your gear. What I do take issue with is your experience on the matter, that is all. And the fervor you discredit the observations that took me a LOT of effort to both enjoy and come to. HD 595 was my first phone, and dude, I respect you, no harm done. But I admonish that only those with experience speak on the matter. Their opinion is the one that really matters on this topic and I think that if you tried a recable you would appreciate it to. I was also skeptical starting out, but both diligence towards my hobby and curiosity has proved otherwise, time and time again.
   
  [Mod Note: Discussion has been moved here: http://www.head-fi.org/forum/thread/555612/cable-discussion-continued-split-from-usb-cable-thread]


----------



## upstateguy

Well it looks like there's been a major correction to the thread.
   
  Probably a good idea to stick with the original question:* Don't get why an audiophile usb cable would improve sound quality.*


----------



## Yoga Flame

The above link is slightly off. This one should work:
   
  http://www.head-fi.org/forum/thread/555612/cable-discussion-continued-split-from-usb-cable-thread


----------



## Hennyo

Please follow along as there are some interesting developments going on with the topic. ^^


----------



## justanut

Back to the topic...
   
  After so many sparring sessions, can someone enlighten me as to the physical differences between "Audiophile" USB cables and normal ones? Personally I've only seen difference in cable material, plating on the USB plugs etc. There's no chip or circuitry built in to improve on the data transmission is there? If there are, maybe it helps cut down on errors along the short digital path taken... other wise, i really don't see how using more expensive materials would improve on digital data...?


----------



## DaBomb77766

Quote: 





justanut said:


> Back to the topic...
> 
> After so many sparring sessions, can someone enlighten me as to the physical differences between "Audiophile" USB cables and normal ones? Personally I've only seen difference in cable material, plating on the USB plugs etc. There's no chip or circuitry built in to improve on the data transmission is there? If there are, maybe it helps cut down on errors along the short digital path taken... other wise, *i really don't see how using more expensive materials would improve on digital data...?*


 


  Exactly.  The performance of digital cables doesn't seem to be as much about the quality of the materials themselves as much as manufacturing thresholds and such.  But USB is built to a spec, and to be called "USB" it needs to be up to that spec.  I wouldn't be surprised if some "audiophile" USB cables actually weren't up to USB spec...


----------



## vandaven

Quote: 





dabomb77766 said:


> Exactly.  The performance of digital cables doesn't seem to be as much about the quality of the materials themselves as much as manufacturing thresholds and such.  But USB is built to a spec, and to be called "USB" it needs to be up to that spec.  I wouldn't be surprised if some "audiophile" USB cables actually weren't up to USB spec...


 
  +1


----------



## uelover

Quote: 





justanut said:


> Back to the topic...
> 
> After so many sparring sessions, can someone enlighten me as to the physical differences between "Audiophile" USB cables and normal ones? Personally I've only seen difference in cable material, plating on the USB plugs etc. There's no chip or circuitry built in to improve on the data transmission is there? If there are, maybe it helps cut down on errors along the short digital path taken... other wise, i really don't see how using more expensive materials would improve on digital data...?


 


  Come over my place I let you hear =)


----------



## justanut

I'm afraid you'll cry when you hear my $5 usb IC 
  
  Quote: 





uelover said:


> Come over my place I let you hear =)


----------



## uelover

Quote: 





justanut said:


> I'm afraid you'll cry when you hear my $5 usb IC


 


  Haha don't worry I won't. I have a $1 USB IC too XD


----------



## dvw

Since measurement is not possible, I wonder how do these guys do QA.
  Do you hire some one to listen to a cable for a week (short listening time is a NO, NO,) and decide if the cable is good or not?
  And how do you qualify for the job? DBT??? Oh no, that's not allowed.


----------



## vandaven

Quote: 





dvw said:


> Since measurement is not possible, I wonder how do these guys do QA.
> Do you hire some one to listen to a cable for a week (short listening time is a NO, NO,) and decide if the cable is good or not?
> And how do you qualify for the job? DBT??? Oh no, that's not allowed.


 

 Measurement is possible. It just doesn't make a difference.


----------



## justanut

I suspect that there is something that the "audiophile" USB cables are doing right and the cheap ones aren't, but its not in the material. And definitely there are also cheap ones that do it right.
   
  Its funny how we're always arguing about how materials affect the normal speaker/headphone/IC cables, which still has some chance of actually being true (since different metals do conduct EM waves differently), and yet here we are again with the same arguments, but about something that can't be true, (all things being equal, difference being the metal used).
   
  In the end I guess its your money. Why we're arguing so hard here is cos those of us who know there's no difference really want our brothers here to save some hard earned cash...


----------



## Currawong

Quote: 





justanut said:


> I suspect that there is something that the "audiophile" USB cables are doing right and the cheap ones aren't, but its not in the material. And definitely there are also cheap ones that do it right.
> 
> Its funny how we're always arguing about how materials affect the normal speaker/headphone/IC cables, which still has some chance of actually being true (since different metals do conduct EM waves differently), and yet here we are again with the same arguments, but about something that can't be true, (all things being equal, difference being the metal used).
> 
> In the end I guess its your money. Why we're arguing so hard here is cos those of us who know there's no difference really want our brothers here to save some hard earned cash...


 

 You have to be careful what you think you know. Not too far over a century and a half ago, doctors thought it was unnecessary to wash their hands between seeing patients and ran one out of the profession for suggesting otherwise.  Not saying you're necessarily wrong, but I do see a lot of incompleteness and factual distortion posted on the forums.  I don't doubt that at some points I've been guilty of this too.


----------



## LizardKing1

Can we hear from the Locus 3500$ USB IC again please? It was getting interesting
	

	
	
		
		

		
		
	


	



   
  I am very noobish in the field of digital cables, but tell me this: even if there is a difference, is it noticeable enough to pay 300$ for it? Yes, yes, I know, it's your money, but if you think it's a good purchase, you'll have no problems in answering.
   
  PS: I loved that post about how, in a digital cable, errors aren't represented as little frequency roll-offs or small blurschanges in the shades of a certain color, but more as in complete distortion of the original information. It made a lot of sense and maybe a lot of the posters should read it.


----------



## justanut

True true~ Still... telling me using gold or silver transmits better quality 1s and 0s is kinda >..<
  
  Quote: 





currawong said:


> You have to be careful what you think you know. Not too far over a century and a half ago, doctors thought it was unnecessary to wash their hands between seeing patients and ran one out of the profession for suggesting otherwise.  Not saying you're necessarily wrong, but I do see a lot of incompleteness and factual distortion posted on the forums.  I don't doubt that at some points I've been guilty of this too.


----------



## dvw

The chips; op amp, DAC etc are connected to leads by gold wire. With the gold price at $1500/oz, lots of chip now uses copper for connection. So new amps and DAC produced in 2010 and 2011are a mix of gold and copper wired chips. I wonder if anyone can tell the difference or even know they are now listening to copper instead of gold.


----------



## Hennyo

Gold is 24% less conductive than copper.... Only used in electronics because there's no rusting or tarnish.. It is effective at preserving contact integrity, and the gold plating is ludocrisly cheap. Your fears should not be any threat to electronics manufacturers for a couple more thousands of dollars/once. Gold plating is that cheap to use.
  Have you ever seen an electronic employ gold wiring? 
	

	
	
		
		

		
		
	


	



   
  You/I probably never will.


----------



## LizardKing1

Then shouldn't gold-plated copper be the best idea ever?


----------



## Hennyo

The gold content that goes into a full blown motherboard is around 1.00 - 2.50 cents. Connectors and all. Tomshardware and other sites have acid-washed/melted down boards just to test it.


----------



## justanut

You guys are confusing analog wave xfer with digital data xfer I think... anyway...


----------



## dvw

Quote: 





hennyo said:


> Gold is 24% less conductive than copper.... Only used in electronics because there's no rusting or tarnish.. It is effective at preserving contact integrity, and the gold plating is ludocrisly cheap. Your fears should not be any threat to electronics manufacturers for a couple more thousands of dollars/once. Gold plating is that cheap to use.
> Have you ever seen an electronic employ gold wiring?
> 
> 
> ...


 
  Yes and plenty. Most silicon chip are wired to their package with gold wire. I am in the middle of qualifying copper wire to replace gold wire. The concern is not conductivity but more for reliability. How well does copper wire stay on? With silicon manufacturing, wire are not soldered but thermally bonded. There are a lot of silicon already converted to copper wiring. So in theory someone will be able to tell their amp or DAC are made from copper or gold if material makes a different in sound even in digital connection.


----------



## vandaven

Quote: 





justanut said:


> You guys are confusing analog wave xfer with digital data xfer I think... anyway...


 

  
  Yep. Unfortunately, it seems that some folks here use all of those audio-equipment-related terms (like THD, analog, digital, jitter etc. plus my personal favorite, "resolving") without really understanding what it means.


----------



## Hennyo

Quote: 





dvw said:


> even in digital connection.


 

DDD ^_^ (couldn't help it)
   
  Not gold wiring to the chip. I'm pretty sure it's all plated contacts...


----------



## drez

the "science" behind many higher end usb (and other) cables just isn't proven, and most of the time is actually WAY off any academic standards.  Correct me if I'm wrong but NONE of the cable manufacturer white papers I have found are peer reviewed, or even to academic standards, and many of claimed technical aspects of the cables have absolutely no scientific or technical credence (or are grossly misrepresented/taken out of context).  It just makes for bad and unreliable development process, and it is hardly ever tested enough, either by the manufacturers OR the consumers to prove actual performance either way.
   
  If manufacturers want to say "our cable has magical powers" and charge $2000 for it, fine, be my guest.  BUT if a manufacturer wants to claim technical and scientific things about their products, it better be fully documented and face up to the scrutiny of engineers and scientists.
   
  There are many technical reasons why audiophile USB cables COULD work, but unfortunately far too many appear to have not been tested properly, or are abandoned altogether in favor of voodoo science by cable companies.  I am equally sure that some cables, expensive or not, are better than others, bus seeing as I don't have the equipment or technical knowledge to test them reliable, I'm not going to be the person to find out.
   
  BTW I am speaking purely in terms of application of scientific theory (Physics).


----------



## DaBomb77766

Quote: 





drez said:


> the "science" behind many higher end usb (and other) cables just isn't proven, and most of the time is actually WAY off any academic standards.  Correct me if I'm wrong but NONE of the cable manufacturer white papers I have found are peer reviewed, or even to academic standards, and many of claimed technical aspects of the cables have absolutely no scientific or technical credence (or are grossly misrepresented/taken out of context).  It just makes for bad and unreliable development process, and it is hardly ever tested enough, either by the manufacturers OR the consumers to prove actual performance either way.
> 
> If manufacturers want to say "our cable has magical powers" and charge $2000 for it, fine, be my guest.  BUT if a manufacturer wants to claim technical and scientific things about their products, it better be fully documented and face up to the scrutiny of engineers and scientists.
> 
> ...


 


  As opposed to pseudoscience?  Physics can explain nearly any phenomena we know of on Earth...I doubt that there are any phenomena that are detectable by our human senses that have not been thoroughly explained already.  Which is why I'm so skeptical about the mythological benefit of audiophile USB cables.
   
  But who knows, science should always be approached with an open mind.  But it doesn't mean you should pass absolutely everything that doesn't fit off as an undiscovered phenomenon before doing proper tests.


----------



## svyr

>As opposed to pseudoscience? Physics can explain nearly any phenomena we know of on Earth...I doubt that there are any phenomena that are detectable by our human senses that have not been thoroughly explained already. Which is why I'm so skeptical about the mythological benefit of audiophile USB cables.

lol, he means as opposed to someone reading a physics|electronics textbook, not understanding any of it, borrowing the terminology/misinterpreting what they read and writing a bs marketing description.  


>But who knows, science should always be approached with an open mind. 

By someone who can measure it (and/or test people being able to tell the difference) and then people don't have to buy it to sponsor the 'omgjusttryit'(to what, see you're susceptible to placebo effect and biases?) theory and audio cable makers with ridiculous profits on each cable


----------



## drez

Quote: 





dabomb77766 said:


> But who knows, science should always be approached with an open mind.  But it doesn't mean you should pass absolutely everything that doesn't fit off as an undiscovered phenomenon before doing proper tests.


 


  My point is that the technological claims made by cable manufacturers are usually unproven, if not completely misapplied and lacking in rigorous logic and research.  Being published by the manufacturers they are almost always completely biased and one sided.  I have an open mind enough to read white papers and marketing material from cable manufacturers, but my trust tends to diminish when the technical claims they make appear not to be backed up by proper research methodology.  It's not like the engineers they employ, if they actually do employ any, have anything better to do with their time.
   
  Isaac Newton, as you may know, spend much of his life researching and developing theories of alchemy.  Needless to say this body of work didn't get him anywhere, we don't know Newton as an alchemist do we.
   
  From the look of most of the cable literature I have seen, cable manufacturers are employing alchemists, not engineers. This is not good enough for me to fork out $400+ on a product that has not been proven to work, or even to be designed based on proper science.
   
  I know plenty of people who will pay thousands of dollars for unproven traditional medicines.  I don't blame them if they are dying of cancer, but what if all they have is a common cold?  What if they merely want to lose some weight?
   
  There is a sound scientific basis for using continuous 75 ohm digital interconnects due to signal reflections: http://focus.ti.com/lit/an/sdya014/sdya014.pdf.  Beyond that its all speculation and alchemy as far as I can tell, and I wouldn't spend a cent on it.


----------



## justanut

Now that makes more sense... and now I understand why Cardas USB cables say "optimized for constant transfer impedance rather than a full wave characteristic impedance". Thanks for the interesting link~ although I couldn't understand half of it haha...


----------



## vandaven

I think within this discussion, we don't even have to go as far as leveling things up to *astrophysics*, because everything in the digital realm is happening in a controlled environment. 
  No matter what ADC was used for the recording, no matter what DAC is used for the transfer back to analog - what is happening in between, as long as there is no signal processing involved, you have the same 44100 samples per seconds with an (information) word length of 16 bits, or 48000 samples 24 bit. It's controlled information within a finite system. 
   
  It's not that esoteric after all.
   
  And to transport that certain information, any cable that is up to the USB standard is fine. Maybe those expensive cables would make a difference if they would be used for the transfer of (infinite resolution) analog information. That's a completely different realm, because, again, the information is of infinite resolution. 
   
  What happens to the USB steam information AFTER it arrived at the DAC is also a completely different story. There, the mysticism begins. For example, I just read an article on the intentional implementation of jitter on the analog outs (and, for the record, that's ONLY analog outs and not on the digital outs) of the Antelope Zodiac DAC to make the signal less "predictable" and more "analog" to the human hearing. But alas, it has NOTHING to do with the USB cable.


----------



## Donnyhifi

Hello all,
   
  I thought all this USB cable discussion discussion was hogwash, its all BS and people who can hear the difference between the different grade of cables were on crack!(jk) 
	

	
	
		
		

		
		
	


	



   
  But in all seriousness I didn't think there would be any noticable difference between the cables provided it was well made.
   
  I went to Dynamic Audio http://www.dynamicaudio.jp/ in Akihabara to pickup the Luxman DA-200 DAC/Headphone Amp that I had placed on order a couple weeks ago and the nice sales lady Sai asked me if I would like to try different USB cables. So at that point I was thinking, hmm, my bladder is about to burst from too much coffee and I better hit the can before I can make a subjective listen.
   
  I returned from the loo and sat down and plugged in a pair of Grado RS1i's and listened to the Furutech cable. The Furutech sounded quality good with sparkly highs good soundstage but with a little bit of sibilance, I figured it sounds good, its cheap(less than $100) and I might as well pickup a pair of Furutechs.
  She then got me to try out the Red Wireworld Starlight which I've heard lots about, after about 10 seconds of listening I couldn't believe my ears!
	

	
	
		
		

		
		
	


	




 The Starlight had better chemistry with the RS1, the sibilance was gone with the highs still airy with a more spread out soundstage and overall fuller sound. I also tried another brand which was more expensive and though it sounded good I thought that the Starlight sounded the best.
   
  I have walked away changing my mindset from being a non believer to ordering a pair of Starlight USB cables.
   
  There definitely is a difference but its not the level of difference you get from changing headphones or amplifiers, its more subtle but its there.
   
  I still don't believe in Power Cords!
	

	
	
		
		

		
		
	


	



  Maybe one day I will A B some demo power cords when I get the time for it.


----------



## svyr

donnyhifi said:


> Hello all,
> 
> I thought all this USB cable discussion discussion was hogwash, its all BS and people who can hear the difference between the different grade of cables were on crack!(jk)
> 
> ...




might be time to start believing in the 'Cables, Power, Tweaks, Speakers, Accessories (*DBT*-Free Forum) ' instead 
Chances are, given a pretty power cord vs that flaky looking black one, you're going to think the pretty one is better  when you look at them, know the price and consider them side by side with full knowledge of what's connected.


----------



## uelover

Quote: 





donnyhifi said:


> Hello all,
> 
> I thought all this USB cable discussion discussion was hogwash, its all BS and people who can hear the difference between the different grade of cables were on crack!(jk)
> 
> ...


 

 Hey Donny,
   
  Nice to see you here! I think that I have been to Dynamic Audio before but I never knew they had USB cables ready for audition.


----------



## Donnyhifi

Hey UElover,
   
  Good to see you here too! They have a laptop on-hand with audio all loaded up and ready to go, they have a pretty sweet setup there, very nice!
   
  svyr,
   
  I actually ended up selecting the less pretty USB cable, I thought the Starlight sounds the best. 
	

	
	
		
		

		
		
	


	



  I just don't believe the Power Cord stuff because there is lots of crappy wiring in between the power plant and wall socket, I can't see how the last 6 feet matters as long as its of descent quality. I use heavy duty server power cables which I've picked up from the office, I think that is good enough.


----------



## kr0gg

Donny, which one did you get?


----------



## endless402

Quote: 





uelover said:


> Hey Donny,
> 
> Nice to see you here! I think that I have been to Dynamic Audio before but I never knew they had USB cables ready for audition.


 


  if you're in japan, you have access to a great selection of usb cables
   
  try out acoustic revive as well (the 2 usb to 1 usb connector, separating power and data). super detailed but doesnt have the warmth.
  i settled on oyaide S+ as the best blend of midrange and detail (less than acoustic revive).
   
  all comes down to component matching in the end


----------



## Donnyhifi

Hi Kr0gg,
   
  I ended up getting the 2m Wireworld Starlight, they don't stock at the moment and I will be picking it up next week.
	

	
	
		
		

		
			




   
  The other Japanese brand that I tried was SAEC, I preferred the Starlight because of the slightly smoother highs but they were very close, both are a step up from the Furutech brand in both price and performance.


----------



## Donnyhifi

Quote: 





endless402 said:


> if you're in japan, you have access to a great selection of usb cables
> 
> try out acoustic revive as well (the 2 usb to 1 usb connector, separating power and data). super detailed but doesnt have the warmth.
> i settled on oyaide S+ as the best blend of midrange and detail (less than acoustic revive).
> ...


 
   
  Thanks! I will try and check it out! 
   
  I totally agree its more about component matching once you get in the better quality cables.


----------



## endless402

Quote: 





donnyhifi said:


> Thanks! I will try and check it out!
> 
> I totally agree its more about component matching once you get in the better quality cables.


 

 yup. i usually get my cables from audiounion in japan. that and amazon.co.jp haha. sometimes audiounion has used usb cables. yodobashi aikba also has a large selection and a dedicated area for PC audio / headphones


----------



## Hennyo

Hey Donnyfi
  Same here. My experience has been identical to your whole first post. I ended up picking the Audioquest Coffee, it's uglier than the other usb's.. but it sounds better on my setup.
   
  Food for thought. 
   
  Hey endless,
  I agree, much of it is system dependent. Everything must be matched.


----------



## uelover

@endless402: Oyaide S+ is a good cable =)  Currently I do not use the power line inside my USB cable so I hope that I will be on the safe side =)
   
  @donnyhifi: You can ask the guy to let you audition the power cord also. Not harm. =)


----------



## drez

Quote: 





donnyhifi said:


> Thanks! I will try and check it out!
> 
> I totally agree its more about component matching once you get in the better quality cables.


 

 Erm ok...  Doesn't seem many people understand digital audio here.  A good digital cable should have no effect on tone or component matching at all (unless your transport and/or computer both have some unorthodox USB sockets...)  If two digital cables sound different, one of them has distortion and is faulty.  A digital cable is either correct in transmitting its digital signal, and does so with low jitter, or it isn't.  Ideally the sockets at both ends should achieve a constant impedance with the cable and connectors.
   
  Digital audio IS NOT analogue audio.  You may wish to change the tone of your system with ANALOGUE interconnects, but if you do this with digital interconnects you are likely going to make your system worse and pay more for the privilege.
   
  Using my essence ST as a transport results in a warm and smooth sound which muddies the details (a little) - this is probably not ideal.  Using my DI in adaptive has a has dropouts.  Using DI with upsampling USB has a non-harsh dynamic, neutral and detailed sound with no dropouts.  This is how my NFB-10ES should sound - so this tells me the transport is doing its job in producing a clean and jitter free signal.  Point is, one of these is producing the most coherent and jitter free signal, and the others aren't.
   
  Same goes for digital cables - they should not change the sound of your system - if they do they are distorting the signal and degrading the performance of your system.  Digital audio is not magic or alchemy, your digital components are (hopefully) not designed by wizards or alchemists (maybe unless it has tubes, but even in this case the USB receiver chip is designed by engineers).


----------



## endless402

in theory they shouldnt. i didnt believe it either but for some reason it does to my ears. even between my cardas lighting 15 coax vs my stereovox xv2 bnc (both of which i dont use anymore as my connection is usb only). my only recommendation is to try it out on your system. if it does something that you like, good, if it doesnt, no need to buy cables. free trials are best     also expensive cables doesnt mean a better sound, it's all tradeoffs between different things. i find more expensive cables to be more detailed but can be quite cold sounding and prefer less resolving stuff. my previous equipment was a high resolution system (all top of the line simaudio equipment) and now i've gone the other route into something warmer and sweeter (accuphase)
   
   
  wait till you get into footers and other tweaks (harmonix footers)...makes no sense whatsoever but changed the sound on my system (some were better and some were worse...all tradeoffs)
   
   
  it's a hobby in the end. i've been through quite a few cables and settled on a harmonix setup as it best complemented my components (seen in my sig).


----------



## kr0gg

Quote: 





drez said:


> Erm ok...  Doesn't seem many people understand digital audio here.  A good digital cable should have no effect on tone or component matching at all (unless your transport and/or computer both have some unorthodox USB sockets...)  If two digital cables sound different, one of them has distortion and is faulty.  A digital cable is either correct in transmitting its digital signal, and does so with low jitter, or it isn't.  Ideally the sockets at both ends should achieve a constant impedance with the cable and connectors.
> 
> Digital audio IS NOT analogue audio.  You may wish to change the tone of your system with ANALOGUE interconnects, but if you do this with digital interconnects you are likely going to make your system worse and pay more for the privilege.
> 
> ...


 


  how do you use DI in async USB?
  Kingwa reported that is a sync device. Its DSP works async, but this has nothing to do with PC-USB connection, only about data transmittion inside the DI.


----------



## uelover

Quote: 





kr0gg said:


> how do you use DI in async USB?
> Kingwa reported that is a sync device. Its DSP works async, but this has nothing to do with PC-USB connection, only about data transmittion inside the DI.


 


  He got mixed up in all the technical jargons without realizing that DI is not an async USB device lol.


----------



## drez

Quote: 





kr0gg said:


> how do you use DI in async USB?
> Kingwa reported that is a sync device. Its DSP works async, but this has nothing to do with PC-USB connection, only about data transmittion inside the DI.


 

 you are quite right it is not async USB chip.  I can see how my post could have been misinterpreted.  Thanks for the polite correction unlike some people who it would seem have nothing better to contribute at this point.
	

	
	
		
		

		
		
	


	



   
  My point is some people might like to introduce distortion into their system with the digital interconnects but to me this just seems the wrong way of doing things.  And as was mentioned, using more expensive digital cables to add flavors of distortion just seem whacky.  
   
  BUT anyway I don't see how that is important to my argument about whether digital interconnects are the right place to introduce distortion.


----------



## Currawong

It would be interesting to see the shape of the waveform through an oscilloscope using the different cables. I do know it looks quite distorted through optical compared to 75 Ohm S/PDIF and the reflections along a cable can be seen in the waveform if you introduce, say, a 50 Ohm adaptor.


----------



## DaBomb77766

I don't understand how people think that distortions in a cable can actually affect the waveform of a digital bitstream.  It may affect it, but not in a consistent way...it'll just be totally random with random errors everywhere.  It won't just modify one part of the signature and that's it.  That's physically impossible given how a digital bitstream works (just a stream of 1s and 0s, not an analog waveform of extremely high resolution and a range of amplitudes.  In a digital bitstream there are only two different variations of the signal - 1 or 0).


----------



## drez

I know it doesn't seem to make sense - but then neither does the effects of transports and there is definite difference between these.  Could just be effect of distortion from jitter?  AFAIK distortion doesn't always appear as noise or treble harshness.


----------



## Hennyo

Seems to me like everybody who's tried it firstly: agrees that they should'nt make a difference..... but then they find...
   
THEY DO make a difference! ahahahahahhaha
   
  We all want to get to the bottom of this, but this sheer thing does make me giggle a-bit.


----------



## Hennyo

Quote: 





endless402 said:


> in theory they shouldnt. i didnt believe it either but for some reason it does to my ears. even between my cardas lighting 15 coax vs my stereovox xv2 bnc (both of which i dont use anymore as my connection is usb only). my only recommendation is to try it out on your system. if it does something that you like, good, if it doesnt, no need to buy cables. free trials are best     also expensive cables doesnt mean a better sound, it's all tradeoffs between different things. i find more expensive cables to be more detailed but can be quite cold sounding and prefer less resolving stuff. my previous equipment was a high resolution system (all top of the line simaudio equipment) and now i've gone the other route into something warmer and sweeter (accuphase)
> 
> 
> wait till you get into footers and other tweaks (harmonix footers)...makes no sense whatsoever but changed the sound on my system (some were better and some were worse...all tradeoffs)
> ...


 

 This. golden.


----------



## Willakan

I googled "Harmonix Footers". I found their cable elevator range. I swore at the rule that prohibits debate based on the forbidden test in all but one forum.


----------



## svyr

willakan said:


> I googled "Harmonix Footers". I found their cable elevator range. I swore at the rule that prohibits debate based on the forbidden test in all but one forum.




If you liked cable elevators, you may also find poo boxes amusing: http://www.head-fi.org/forum/thread/555084/6moons-and-burson-have-been-naughty/45#post_7501836


----------



## Willakan

Quote: 





svyr said:


> If you liked cable elevators, you may also find poo boxes amusing: http://www.head-fi.org/forum/thread/555084/6moons-and-burson-have-been-naughty/45#post_7501836


 

  I had seen that product before, but not 6moons' review of it. This 'twas amusing and also confirmed my preconceptions that 6moons are partially insane. Using their website as a source about audio that actually makes a difference (I see them linked quite a bit around here, scary stuff) seems about as accurate as using the Communist Party of China's website for an unbiased insight into Chinese human rights.


----------



## svyr

willakan said:


> I had seen that product before, but not 6moons' review of it. This 'twas amusing and also confirmed my preconceptions that 6moons are partially insane. *Using their website as a source about audio that actually makes a difference (I see them linked quite a bit around here, scary stuff) seems about as accurate as using the Communist Party of China's website for an unbiased insight into Chinese human rights*.





rofl  +1 "yes, we can't live without this very dubious product that we happen to be advertising on our site"


----------



## vandaven

Hum,
   
  after watching and contributing to this discussion for over a week now I would like to get some proof that there is some difference between usb cables.
  I am sure I made it quite clear with my experiments that from my perspective, even though I would like to believe that they make a difference, they don't.
  But maybe it's the wrong perspective? Who knows.
   
  Nonetheless, simple statements like "they make a difference" because "I feel it / sense it" actually belong into fairytales and religion and saying "it is so" without holding any proof in your hands belongs to kindergarden-land.
   
  You can do measurements by yourself, if you can't, please feel free to PM me so I can send you a test file. If there is a difference (no matter you call it warmth / soundstage / resolution etc.) it can be measured. When performing tests please make sure the only critical part is the usb cable. Thus, a digital connection would be preferred. 
   
  This is a very interesting topic. 
   
  Thank you very much!


----------



## DaBomb77766

I think one interesting thing to try is to test if there's any difference with a USB cable that has a ferrite bead vs one that doesn't.  If anything should make any difference at all, that should.
   
  Or, better yet, the same USB cable with a removable ferrite bead.
   
  Also, I'm beginning to think that some day some hardcore audiophiles are gonna start using superconducting cables when the technology arrives to allow general consumers to use it at a [sort of] reasonable price.


----------



## endless402

Quote: 





willakan said:


> I googled "Harmonix Footers". I found their cable elevator range. I swore at the rule that prohibits debate based on the forbidden test in all but one forum.


 

 should try them! haha i havent. i've only tried the equipment footers. didnt like the sound of them since they took away the edginess of my system.
   
  FYI K2 mastering uses harmonix cabling. they seem to believe it works for their purpose


----------



## endless402

Quote: 





vandaven said:


> Hum,
> 
> after watching and contributing to this discussion for over a week now I would like to get some proof that there is some difference between usb cables.
> I am sure I made it quite clear with my experiments that from my perspective, even though I would like to believe that they make a difference, they don't.
> ...


 



 how do you measure soundstage depth?


----------



## tmars78

Quote: 





endless402 said:


> how do you measure soundstage depth?


 
   
  Are you insinuating that cables make up soundstage? I think its the recording, not the cable. If the source lacks soundstage, its going to lack it with a $1 cable or a $1,000,000 cable. Even with my modest set up, some recordings have a much larger soundstage than others, which leads me to believe its the recording.


----------



## Steve Eddy

Quote: 





hennyo said:


> Seems to me like everybody who's tried it firstly: agrees that they should'nt make a difference..... but then they find...
> 
> THEY DO make a difference! ahahahahahhaha


 

 So does putting photographs of yourself in your freezer.
   
  Your point?
   
  se


----------



## Steve Eddy

Quote: 





endless402 said:


> How do you measure soundstage depth?


 
   
  That one's so old it's got whiskers.
   
  You don't have to measure "soundstage depth" (which by the way is a psychoacoustical phenomenon that exists only in our minds, rather like "stereo").
   
  In the electrical domain, all we have is changes in voltage and current over time. Any difference between two devices which is sufficient to audibly change the perception of soundstage depth would manifest itself as a difference in the changes in voltage and current over time between the two devices.
   
  If there's no difference in this between two devices, then there can be nothing there with which to cause an audible change in the perception of soundstage depth. Which means you have to go looking elsewhere for the cause of that perceived change, such as the human mind which we have known for many decades is prone to subjectively perceiving differences even when there are no actual physical differences to account for it.
   
  se


----------



## Hennyo

Quote: 





dabomb77766 said:


> I think one interesting thing to try is to test if there's any difference with a USB cable that has a ferrite bead vs one that doesn't.  If anything should make any difference at all, that should.
> 
> Or, better yet, the same USB cable with a removable ferrite bead.
> 
> Also, I'm beginning to think that some day some hardcore audiophiles are gonna start using superconducting cables when the technology arrives to allow general consumers to use it at a [sort of] reasonable price.


 

 I've done this! To two Kimber Kable usb's. These were a couple of the cables I demoed for a couple weeks. Their lower end one has ferrite beading @ both ends (I think they're also removable), It was benchmarked against their higher usb cable, which was actually a more competitive cable. My impression was Ferrite beading made little difference as opposed to not having Ferrite beads. I did not like the sound of the Ferrite cable. It was harsh and unresolving/sibilant.The higher end Kimber was a polar opposite, sounding smoothly natural and pleasing.
 The Ferrite cable was this one:
  http://www.kimber.com/products/interconnects/digital/usb/minibus/cu/
   
  and the higher end Kimber was this one. This is probably the most 'natural' sounding cable I've heard. It was particularly good for 'garage band' tracks.
  http://www.kimber.com/products/interconnects/digital/usb/minibus/ag/
   
  Ferrite beading seems very gimmicky to me.


----------



## justanut

Eh... the moment I see the words "harsh" "sibilant" "natural" "pleasing", it seems to me that it wasn't a scientific experiment. Its like art... what may be natural to you could be harsh to someone else... and again... how USB cables can affect whether the sound's harsh or sibilant is beyond my understanding~
   
  I second Vandaven's proposal for some else (preferably a "believer") to conduct a proper scientific test with the *USB cable* being the only variable. Resulting variations in frequency response maybe? Charts? I dunno...
  
  Quote: 





hennyo said:


> I've done this! To two Kimber Kable usb's. These were a couple of the cables I demoed for a couple weeks. Their lower end one has ferrite beading @ both ends (I think they're also removable), It was benchmarked against their higher usb cable, which was actually a more competitive cable. My impression was Ferrite beading made little difference as opposed to not having Ferrite beads. I did not like the sound of the Ferrite cable. It was harsh and unresolving/sibilant.The higher end Kimber was a polar opposite, sounding smoothly natural and pleasing.
> The Ferrite cable was this one:
> http://www.kimber.com/products/interconnects/digital/usb/minibus/cu/
> 
> ...


----------



## vandaven

Quote: 





tmars78 said:


> Are you insinuating that cables make up soundstage? I think its the recording, not the cable. If the source lacks soundstage, its going to lack it with a $1 cable or a $1,000,000 cable. Even with my modest set up, some recordings have a much larger soundstage than others, which leads me to believe its the recording.


 

 Indeed you're right. It's actually not the stereo microphone technique we're using for recording (classical music), it's mainly the mic cables that make the difference in soundstage 
	

	
	
		
		

		
			





. Often, we tend to record in mono, because we only need one [esoteric german tube] microphone (one mic = cheaper = more money for interconnects) and then plug our usb audio interface (that we're recording with) into the workstation via the most expensive usb cable we can afford. This process, often called "questing", will convert the mono signal to a stereo signal with an unbelievable soundstage, warmth and natural smoothness. This is how audiophile recordings are done.
   
  If we have to record for lower budget, we basically record via iPhone and let the listener's equipment do the rest. 
   




   
  Please excuse my sarcasm but I felt it was about time. 
   
  P.S.: Anyone who wants to enjoy the "natural, smooth sound of music" should either go to a classical concert (preferably a quality orchestra playing in the right hall) or learn to play an instrument.


----------



## drez

I'm guessing the engineers who designed the akg k701 and senheisser hd800 would probably have  a pretty good idea what is behind soundstage in audio reproduction.


----------



## endless402

Quote: 





drez said:


> I'm guessing the engineers who designed the akg k701 and senheisser hd800 would probably have  a pretty good idea what is behind soundstage in audio reproduction.


 


 they prob do. the soundstage is tiny compared to speakers still.


----------



## LizardKing1

I thought speakers didn't reproduce soundstage, since you decide how far they are from you. I mean, it's not a fair competition: If I put a speaker 3 meters away from me, I can say "yeah, that's much better than those K701" - well no kidding! The K701 are right next to your ear, and it probably takes a lot of effort to recreate the feeling that the music is being played 3 meters away from you. I raise my glass to AKG!


----------



## Iniamyen

Quote: 





endless402 said:


> they prob do. the soundstage is tiny compared to speakers still.


 

 I would argue that the soundstage is actually "bigger" when listening to headphones. The sound is coming from all around you, as opposed to primarily in front of you (or wherever your speakers are.)
   
  A more accurate statement might be that the soundstage is _less directional_ compared to speakers. Bottom line is that "soundstage" can't really be quantified, so who really cares?


----------



## uelover

This is something I saw on Oyaide's sister company (NEO) comparing a standard stock USB cable (Top) VS their d+ USB cable (Bottom)
   
  It is a print screen of the eye pattern on their oscilloscope display in which a 'digital data signal from a receiver is repetitively sampled and applied to the vertical input, while the data rate is used to trigger the horizontal sweep.'
   

   
  Link: http://www.neo-w.com/catalog/2010/06/d-usb.html


----------



## vandaven

Thank you very much for the oscilloscope screen print. This seems to be at least some proof that the cable is high quality and the signal obviously seems to be benefiting from that fact. From what I've seen, those NEO cables sell for as low as 60 US$? That's still a very reasonable price. 
   
  Nonetheless it was never questioned whether "expensive" USB cables are of a higher built quality, conductivity etc. 
   
  Question is from what point on there is an audible difference (or even IF there is an audible / significant difference), so the investment really makes sense. From my tests, all I can say is that up to a sampling rate of 48 kHz 24 bit, the difference is so insignificant that it makes no difference to the (usb) signal what usb cable is being used.
   
  If the whole thing would be happening in the analog realm, chances are high that it would make a difference. But alas, it's not.


----------



## upstateguy

Quote: 





uelover said:


> This is something I saw on Oyaide's sister company (NEO) comparing a standard stock USB cable (Top) VS their d+ USB cable (Bottom)
> 
> It is a print screen of the eye pattern on their oscilloscope display in which a 'digital data signal from a receiver is repetitively sampled and applied to the vertical input, while the data rate is used to trigger the horizontal sweep.'
> 
> ...


 

 Has this been reproduced anywhere or are we supposed to believe everything a manufacturer says on their web site? <--- just asking


----------



## Prog Rock Man

Both QED and Blue Jeans cables refer to the 'eye' and how it can be disrupted, in their case it is with HDMI cables. But since both HDMI and USB are digital, it should apply to both. They both state it is important to keep the 'eye' open and clear to be read, which makes sense.
   
  But what they and others fail to do is hsow what happens if the 'eye' is unreadable. I would suggest if that happens then there will be a break in the signal which would appear as a crackle or silence or click and not less bass, narrower soundstage or shrill treble.
   
  The 'eye' is one of a long list of examples of how cables can be found to be different, but with no proven link to that difference is audible. Cables either work or they do not.


----------



## Currawong

My suggestion: If a DAC seems to output audibly different sound, eg: more sibilance with a cheaper cable (as someone wrote about previously) and less with a more expensive one, if the "eye" is different, then also measure to see if there are any changes in the analog output of that DAC. The reason I suggest this is, I've owned quite a few DACs, some of which seemed to be affected significantly by what they were plugged in to and how, and others which sounded exactly the same whether I connected them with optical, coax or whatever other input or source device.


----------



## DaBomb77766

http://gizmodo.com/266616/the-truth-about-monster-cable
  http://gizmodo.com/268788/the-truth-about-monster-cable-part-2-verdict-cheap-cables-keep-upusually
  http://gizmodo.com/282725/the-truth-about-monster-cable-+-grand-finale-part-iii
   
  Here are some articles right here about Monster's HDMI cables.  Interesting reads.


----------



## Prog Rock Man

There are other threads in Sound Science about testing of HDMI cables. They reach the same conclusion as the Monster cable test you link to. Cables either work or they do not and when they do not the picture starts to degarde with ghosting, pixelation etc and that occurs as the cable gets too long. There is no correlation between the price of the cable and how soon it starts to fail.


----------



## vandaven

Quote: 





currawong said:


> The reason I suggest this is, I've owned quite a few DACs, some of which seemed to be affected significantly by what they were plugged in to and how, and others which sounded exactly the same whether I connected them with optical, coax or whatever other input or source device.


 
   
  This sounds very interesting. Do you own any computer or similar device that would allow you to record the (line) output of your different DACs or maybe the certain DACs that are more dependent on USB cable quality? As I am limited with my resources of consumer DACs to test, I would happily forward you a test file I have created (sine wave, impulses etc.). If you re-record that file via DAC / line input with different USB cables and different DACs and send me the results, I could analyze them here in the studio. Maybe that would put some light in the dark. Of course, the postings would be posted in the parallel thread on the sound science part of the forum. 
   
  Please feel free to PM me.


----------



## uelover

Quote: 





vandaven said:


> This sounds very interesting. Do you own any computer or similar device that would allow you to record the (line) output of your different DACs or maybe the certain DACs that are more dependent on USB cable quality? As I am limited with my resources of consumer DACs to test, I would happily forward you a test file I have created (sine wave, impulses etc.). If you re-record that file via DAC / line input with different USB cables and different DACs and send me the results, I could analyze them here in the studio. Maybe that would put some light in the dark. Of course, the postings would be posted in the parallel thread on the sound science part of the forum.
> 
> Please feel free to PM me.


 


 I am wanting to try something that USG had suggested.
   
  I can connect the RCA output of my DAC to the 3.5mm line-in of my Mac and record the outputted audio using Logic Pro and then send the file to someone else to analyze.
   
  However, I have no RCA to 3.5mm cable at the moment.
   
  If Currawong could do that it would be great!


----------



## uelover

Quote: 





upstateguy said:


> Has this been reproduced anywhere or are we supposed to believe everything a manufacturer says on their web site? <--- just asking


 

 I haven't seen anyone reproducing that.
   
  Some generous soul who could do this experiment would be very much appreciated.


----------



## justanut

This leads me to think about a discussion about Gold CDs vs normal CDs... In the case of recording as an Audio CD, there were claims that the SQ would be better... ok... maybe... but if anyone says that MP3s recorded on Gold CDs would sound better, would you buy it? Effect of medium on Analog vs Digital... sound familiar?


----------



## Iniamyen

Quote:


justanut said:


> This leads me to think about a discussion about Gold CDs vs normal CDs... In the case of recording as an Audio CD, there were claims that the SQ would be better... ok... maybe... but if anyone says that MP3s recorded on Gold CDs would sound better, would you buy it? Effect of medium on Analog vs Digital... sound familiar?


 

 Audio CD and mp3 CD are both digital, because the format is digital. There's no way to store analog data on a CD. So it stands to reason that if there is a difference between a regular and a "gold" CD, that difference would manifest itself over all uses of the medium. I guess making photo backups is out of the question now that I know my JPEGs will have "washed out color" and "reduced saturation."


----------



## DaBomb77766

I'm pretty sure the only benefit to a gold CD is that it'll last pretty much forever.


----------



## Willakan

That's easy, lots of audiophile (and non-audiophile) cable terminations are gold plated, so take that fact, exploit the second fact that some people don't understand why that is the case and release magical gold CDs that will make everything sound better!


----------



## Prog Rock Man

Gold, silver, shiny shiny, mmmmm, better.......


----------



## JadeEast

Quote: 





uelover said:


> This is something I saw on Oyaide's sister company (NEO) comparing a standard stock USB cable (Top) VS their d+ USB cable (Bottom)
> 
> It is a print screen of the eye pattern on their oscilloscope display in which a 'digital data signal from a receiver is repetitively sampled and applied to the vertical input, while the data rate is used to trigger the horizontal sweep.'
> 
> ...


 

 I'm certainly not an EE. But I'm not seeing that the bottom example would be a demonstration of a superior performance. The top cable displays a near symmetrical placement of the usb signal over the sample window. The bottom cable has the symmetry shifted in both the shape of the wave form and the placement of the waveform in the sample window. Again I'm not an EE so if anyone can clarify or correct my interpretation please do.
   
  Based on the visual evidence in the graph I would conclude (rightly or wrongly) that the top cable is superior performing due to it's symmetry. If the difference is audible is another question all together.


----------



## svyr

willakan said:


> That's easy, lots of audiophile (and non-audiophile) cable terminations are gold plated, so take that fact, exploit the second fact that some people don't understand why that is the case and release magical gold CDs that will make everything sound better!




lol (certainly not because gold plated connectors don't easily oxidize  - rusty connector = bad )


>I guess making photo backups is out of the question now that I know my JPEGs will have "washed out color" and "reduced saturation."

hehehe...  you should probably say RAW, not jpeg... 


>m certainly not an EE. But I'm not seeing that the bottom example would be a demonstration of a superior performance. The top cable displays a near symmetrical placement of the usb signal over the sample window. The bottom cable has the symmetry shifted in both the shape of the wave form and the placement of the waveform in the sample window. Again I'm not an EE so if anyone can clarify or correct my interpretation please do.

I believe the intended interpretation is - the top graph has more variability over the repeated signals (over the time window) (and perhaps the bottom graph has a more square waveform). Consequently, the cumulative trace picture for the 'stock' cable is thicker resulting from less consistent paths... It only makes a difference if a) the manufacturer didn't fudge that in Matlab and did the measurements and calibration correctly/kept everything but the cable the same b) if the receiving hardware considers the variations to be enough to misinterpret a 1 for a 0 (low for a high). (that's pretty unlikely)


----------



## Prog Rock Man

There are lies, damned lies and then there are graphs.


----------



## svyr

it's interesting that on the top graph/the first segment, the variability (I take it the thickness of the graph) is about +-150mV (!!)... That's for a +-350mv signal. To suggest the 'stock' cable will have about 40% variability seems a bit far fetched. Unless it's made out of a coathanger ...


----------



## JadeEast

Again I'll mention that I am not an EE. But I do have some experience in creating info-graphics. One of the thing in creating (good) info graphics is that you try to make sure is that the scales for comparisons on graphs are the same. On re-looking at the two graphs there not even at the same scale. Possibly just a personal tick, but it kind of bugs me when graphs get shown for comparison and they don't relate on scale. It makes using the graphs for visual comparison a bit less useful.


----------



## Currawong

Quote: 





vandaven said:


> This sounds very interesting. Do you own any computer or similar device that would allow you to record the (line) output of your different DACs or maybe the certain DACs that are more dependent on USB cable quality? As I am limited with my resources of consumer DACs to test, I would happily forward you a test file I have created (sine wave, impulses etc.). If you re-record that file via DAC / line input with different USB cables and different DACs and send me the results, I could analyze them here in the studio. Maybe that would put some light in the dark. Of course, the postings would be posted in the parallel thread on the sound science part of the forum.
> 
> Please feel free to PM me.


 

 I have been pondering getting an Apogee Duet 2, but I'd want something with an equal or lower level of distortion than my DAC.  There is an oscilloscope attachment for iPads as well, with software, which I also plan to get for testing things.  To add to that, there is a recently registered forum member who has been testing digital gear with some serious hardware that can measure down to femtoseconds. With Tyll Hertsens and others interested in doing serious measurements, there's a great possibility we might be able to extract useful info about digital gear.
   
  Quote: 





uelover said:


> I am wanting to try something that USG had suggested.
> 
> I can connect the RCA output of my DAC to the 3.5mm line-in of my Mac and record the outputted audio using Logic Pro and then send the file to someone else to analyze.
> 
> ...


 

 I'd be concerned that the noise floor of the Mac would be quite high, so I was going to get something with a very low noise floor and low distortion first before I tested anything.  It's not something I plan to do in any hurry though.


----------



## Prog Rock Man

Currawong, how do you plan to link any test results to what is actually audible and any notion that the results are related to differences in sound quality?
   
  It is clear from having spent a lot of time going through cable maker's claims, that none of them can link differences to audiblity, let alone different sound quality. They do however, successfully prove different cables measure differently. So all you would (and any other who measures cable differences) do is add to that existing knowledge.
   
  So we would still not be able to answer the question of why audiophile USB cables improve sound quality.


----------



## drez

the fact that people are actually measuring the signal performance of digital cables now is promising - at least for those of us who don't like distortion in our systems.


----------



## Prog Rock Man

True, but the cable makers have already been doing this for some time now. Is it really useful to verify what we already know when we need to takle the real issue, the lack of a proven link between the way a cable is made and claims of improved sound quality.


----------



## Prog Rock Man

If USB made a difference to sound quality, surely that would be a useful selling point for the USB cable makers here http://www.usb.org/home ? But there is only referencing to the standards need to make a USB and its connectivity.


----------



## Yoga Flame

Testing for any difference at all in the analog domain while swapping USB cables is worthwhile, IMO. The audibility of those differences, if any, can be found later by analyzing the measurements or through follow up tests.


----------



## Prog Rock Man

Quote: 





yoga flame said:


> Testing for any difference at all in the analog domain while swapping USB cables is worthwhile, IMO. The audibility of those differences, if any, can be found later by *analyzing the measurements or through follow up tests.*


 

 What would that entail?


----------



## Yoga Flame

I don't recall the exact number off hand (-90db ?), but noise below a certain level is inaudible to humans. If analysis fails to produce anything conclusive, then the Voldemort test can be done.


----------



## Prog Rock Man

Sadly, being inaudible to humans does not stop some from claiming they can 'feel' the difference and not realising that puts the difference down to them and not the construction of the cable.


----------



## dvw

I do not believe making the measurement in the analog domain will make sense. For one, there will be more variance added on; D to A converters, amplifier, noise etc. The key is what is the cable changing. Take a quiet signal;
   
  1000000000000000 1000000000000000 10000000000000000 100000000000000
   
  Will it add noise like this
  011111111111111 1000000000000000 10000000000000001 1000000000000000
   
  or create random error like this
   
  1000000000000000 1000001000000000 10000000000000010
   
  In the first case, you'll need a cable that have intelligence to know where to "change" the bit word.
  In the second case you'll be hearing lots of pop and click.
   
  Basically, it either work or it doesn't. And better highs and lows are simply not possible.


----------



## t-h-e-p-i-m-p

http://www.referenceaudio.se/ImageUpload/Nordost/Blue-Heaven-LS-USB.jpg

 great usb cable! i compared it to some random no-name usb cable. And there is a pretty big noticeable different between them!


----------



## 12345142

Quote: 





t-h-e-p-i-m-p said:


> http://www.referenceaudio.se/ImageUpload/Nordost/Blue-Heaven-LS-USB.jpg
> 
> great usb cable! i compared it to some random no-name usb cable. And there is a pretty big noticeable different between them!


 

 Of course there's a noticeable difference, the Nordost is blue.


----------



## svyr

12345142 said:


> Of course there's a noticeable difference, the Nordost is blue.




and gold


----------



## Prog Rock Man

Quote: 





t-h-e-p-i-m-p said:


> http://www.referenceaudio.se/ImageUpload/Nordost/Blue-Heaven-LS-USB.jpg
> 
> great usb cable! i compared it to some random no-name usb cable. And there is a pretty big noticeable different between them!


 


  Do you know why that is?


----------



## vandaven

Quote: 





t-h-e-p-i-m-p said:


> http://www.referenceaudio.se/ImageUpload/Nordost/Blue-Heaven-LS-USB.jpg
> 
> great usb cable! i compared it to some random no-name usb cable. And there is a pretty big noticeable different between them!


 


  Nordost also sells some spray-on that is supposed to make your cables and speakers sound less harsh. People say that stuff also makes quite a big difference. Quite suspicious, I daresay... 
  On the other hand, I just bought a wonderful USB-audio interface made by a respected company in the pro business that is, among other things, designed for audio measurements. Together with my Schiit Asgard, it's the best sounding headphone system I have ever heard. Measured the linearity of the AD-DA yesterday, and it's straight as straight can be.
   
  The USB cable that comes with it is a no-name one.


----------



## upstateguy

nm


----------



## Currawong

I've found one better, which is someone with the calibre of gear capable of measuring digital equipment down to femtoseconds. However, regardless, if we take those measurements Oyaide did of their USB cable, we don't know how the DAC it is used with will be affected or not without knowing enough about and measuring the DAC's performance. It's not something, I think, that can be generalised as being all nonsense or all genuine as different electrical circuits don't behave the same way. Some useful data, _per DAC_, is much needed though. Other than that, I'm not a big fan of the idea of expensive USB cables unless one already has spent a considerable amount of money on (genuinely high quality) digital gear relative to their cost. However it shouldn't matter by then anyway.

As for what is audible, if our eardrums can detect movement of as little as 5 angstroms (equivalent IIRC to someone dropping a pin on tarmac a few miles away) then I'm not going to write off everything below any supposed cut-off as inaudible. On one of the online sites where you can test your hearing, you listen to sine waves at different frequencies which are different from about 1dB down to about 1/16th dB. However the site also has the same tests using square waves, which are far easier to determine the differences between, depending on the frequency being tested. Considering that everyone's hearing ability is different at different frequencies, dependant on the waveform, the type of music, the noise floor of the gear used and how that gear is affected by its digital input electrically and any jitter and how that tonally distorts the sound if at all (see what Dan Lavry wrote in another thread about the effects of jitter), the most one might say is that something is unlikely to be audible. This goes for any equipment, not just cables.

Arguing about whether or not, in this case, expensive USB cables are nonsense or not is actually doing people a disservice. Finding some useful answers that will help people determine if purchases are good value or not, eg: if their DAC will benefit from, say, a higher quality USB to S/PDIF converter (I'm not going to suggest USB cables to someone personally, at least not without their having a worthy cost/performance improvement that is undoubted) and at what point the price/performance ratio suggests they should just spend the money on better gear I think is considerably more valuable.


----------



## throzen0303

Can't believe the amount of people reply to my post@.@ Learning my way though,
  Should I invest into a AudioQuest Forest USB for $30(1.5m), to my $140 DAC(Custom Build)


----------



## vandaven

Quote: 





throzen0303 said:


> Can't believe the amount of people reply to my post@.@ Learning my way though,
> Should I invest into a AudioQuest Forest USB for $30(1.5m), to my $140 DAC(Custom Build)


 

 You could buy the AudioQuest because it's green and not too expensive (in comparison to a Locus Cynosure). Especially at this length, I am 99.99999% sure that it won't make a difference with any other USB cable that's the same length. As much as my time allows, I have been repeating my test with different usb cables and different converters and there was no measurable difference.  
   
  Cheers.


----------



## DaBomb77766

Quote: 





vandaven said:


> You could buy the AudioQuest because it's green and not too expensive (in comparison to a Locus Cynosure). Especially at this length, I am 99.99999% sure that it won't make a difference with any other USB cable that's the same length. As much as my time allows, I have been repeating my test with different usb cables and different converters and there was no measurable difference.
> 
> Cheers.


 


  Hm, have you tried adding a few extensions to the cable to make it longer than the USB spec allows?  It would be interesting to see how long the cable could get before it starts to distort the signal.


----------



## throzen0303

Quote: 





vandaven said:


> You could buy the AudioQuest because it's green and not too expensive (in comparison to a Locus Cynosure). Especially at this length, I am 99.99999% sure that it won't make a difference with any other USB cable that's the same length. As much as my time allows, I have been repeating my test with different usb cables and different converters and there was no measurable difference.
> 
> Cheers.


 

 LOL "You could buy the AudioQuest because it's green", love that line
  Nah, don't have time to buy something that I makes no difference and something that I can't see LOL
   
  BTW My system now is Computer Audio > [DIR9001+PCM2706+WM8740 Parallel Mono DAC Coaxial+USB] (Yet to be built for me) > Musical Paradise MP301 MK2 EL34B (Yet to be shipped><) > PSB Alpha B1 Speakers


----------



## 9pintube

In my system the USB cable from the iMac into the John Kenny Mod Hi Face makes no difference, ( and I'm a Cable believer)!!!   Fellow Head-Fi'er Bubu1 and I  realized the USB cable isn't using any power (from the mac) and therefore any good USB cable with "this system" will work fine, Remember it's just "info" being sent through the cable to the JK Hi-Face! ..... So have you noticed the adds for the big buck USB cables, most show their cross sectioned design and that shows the power and the signal that make up the USB design is separated in the cables dielectric, making a difference, in other systems.. Remember, that equates to more $$$ in making those USB cables.......Now after coming out of the Hi-Face the cables, be it, a 75ohm digital or a true 75ohm BNC into mine/ours or your Dac matter BIG TIME If you can't hear a difference then well what can i say........      But for guy's like *throzen0303, *who is going from source straight into his Dac There could and should be a difference with a well built and well designed USB cable when used in this apt.   But, I'd listen 1st to the big buck cables if at all possible... This is JMO and what I hear, I'll even include what Tom heard....also... Believe me we've tried several in both of our systems......   Cables do make a difference when matched with your other components........


----------



## justanut

I think the biggest worry many of us have is whether the USB cable will become the weakest link in our setup. And thats what the various marketing people have our *ahem* balls by... After spending thousands on your audio system, are you going to scrimp on that $100 USB cable and risk the chance that it MAY be the weakest link? And that's where they earn their 10000% profit off...
   
  Despite my belief that USB cables aren't going to change what is being sent via 1s and 0s to my DAC, if it comes down to it, yes I think I will spend on a more expensive USB cable, maybe not for the "sonic improvements" but for the better build-quality and looks... That about sounds up how this discussion will go down yes no?


----------



## DaBomb77766

I think our weakest link is our brain.  It's like when somebody with a pair of Beats criticizes your nice HD25s saying that they suck compared to them.


----------



## uelover

Quote: 





9pintube said:


> So have you noticed the adds for the big buck USB cables, most show their cross sectioned design and that shows the power and the signal that make up the USB design is separated in the cables dielectric, making a difference, in other systems..


 
   
  I don't think it can be generalized in that way.
  
  I am using Audio-GD DI with their Class A PSU. I am only using the data line of my USB cable and yet a good USB cable affects the sound.
   
  However, on my iQube V2, the wireworld USB-Mini cable doesn't really do much of anything (even though I am tapping on its power line) which is why I sold it away.


----------



## drez

Quote: 





justanut said:


> I think the biggest worry many of us have is whether the USB cable will become the weakest link in our setup. And thats what the various marketing people have our *ahem* balls by... After spending thousands on your audio system, are you going to scrimp on that $100 USB cable and risk the chance that it MAY be the weakest link? And that's where they earn their 10000% profit off...


 

 You're onto something there - I'm pretty sure this dumb logic is what drives most people to pay for unproven and unreasonable technology.  The fact that many don't back up their products with measurements, even when they perform a technical function (like a USB cable) adds insult to injury.
   
   
   
  Quote: 





> Originally Posted by *Currawong*
> 
> Some useful data, _per DAC_, is much needed though. Other than that, I'm not a big fan of the idea of expensive USB cables unless one already has spent a considerable amount of money on (genuinely high quality) digital gear relative to their cost. However it shouldn't matter by then anyway.


 
   
  Even some useful data considering the USB sockets used, USB receiver chip etc.  Considering the plainly insulting aspects of some of Oyaide's power products here (bottom of page - feet of power filter changing sound LOL) I wouldn't buy any of their products out of principle - but lets not derail this topic by getting into power cables.
	

	
	
		
		

		
			




   
  The test I would like to see is a recording and comparison of the digital data retrieved from the USB cable, not just the waveform which could be [mis]interpreted, but at least this is better than a purely subjective description of a digital cable's "sound."  But yeah would you buy something from a company that sells other [partially or fully] snake oil products?


----------



## justanut

I haven't really gone to look at the inner workings of either device, but could it be that the iQube V2 was actually better designed? I mean... you looked at it as the iQube not being able to optimize the potential of your USB cable, but I saw it the other way round~ Maybe the Audio-GD needed the extra something from the more expensive USB cables to work properly? 
	

	
	
		
		

		
		
	


	



   
  Just speculating... There must be some logical reason why people say there are audio differences... Transmitting 1s and 0s through different mediums can't make the sound warmer or clearer or increase the soundstage. So what exactly is the difference that people hear?

  
  Quote: 





uelover said:


> I don't think it can be generalized in that way.
> 
> I am using Audio-GD DI with their Class A PSU. I am only using the data line of my USB cable and yet a good USB cable affects the sound.
> 
> However, on my iQube V2, the wireworld USB-Mini cable doesn't really do much of anything (even though I am tapping on its power line) which is why I sold it away.


----------



## Prog Rock Man

Quote: 





justanut said:


> I haven't really gone to look at the inner workings of either device, but could it be that the iQube V2 was actually better designed? I mean... you looked at it as the iQube not being able to optimize the potential of your USB cable, but I saw it the other way round~ Maybe the Audio-GD needed the extra something from the more expensive USB cables to work properly?
> 
> 
> 
> ...


 

 The evidence points to the difference in audibility being down to the listener and the effects of cable maker/reviewer/audiophile hype about cables creating better sound.
   
  If you read what cable makers claim about their cables, it only suggests differences in how a cable is made that make a difference to sound quality. They cannot link anything in the way a cable is made to differences in sound quality. It is the same tactic with many audiophiles. They suggest that things may be audible, even if it is measurable in the smallest of measurements. Both promote non sequiturs as they constantly ignore the effect of hype.
   
  You are more likely to hear a difference in cables if you believe the hype.


----------



## DaBomb77766

Quote: 





justanut said:


> I haven't really gone to look at the inner workings of either device, but could it be that the iQube V2 was actually better designed? I mean... you looked at it as the iQube not being able to optimize the potential of your USB cable, but I saw it the other way round~ Maybe the Audio-GD needed the extra something from the more expensive USB cables to work properly?
> 
> 
> 
> ...


 


  Placebo.  It's not like placebo is some weird and mystical thing, it's proven to exist and be quite effective in various areas of medicine and psychology.


----------



## Currawong

You have to indeed be careful you aren't fooling yourself. I can only speak for myself when I say I've often expected something to make no difference at all and found a difference for which I don't have an explanation for. I think a better attitude to have is to find out the cause rather than declare everything as being placebo or whatever. Deciding on only one truth is not scientific, even if one's belief is related to science.

I think it is inside DACs that we will need to be looking for our answers though. Either we get someone to make measurements (I'm working on that) or this thread ends being being a bunch of audiophiles and non-scientists chest-beating their beleifs. Which do you reckon is better?


----------



## vandaven

Just a bit of an add-on from my side: 
   
  I have been turning the spike around and did some conductivity / resistance measurements with the more expensive usb cables today. And I won't even discuss the fact that these cables are of a better conductivity (thus, less resistance) than their no-name counterparts. Again, I need to emphasize that this might make a difference at longer cable lengths, but in the 1 - 2 meter range, it simply doesn't matter.
   
  Cheers.


----------



## svyr

>I think it is inside DACs that we will need to be looking for our answers though. 

In what sense/what do you want to specifically examine/know about?


>attitude to have is to find out the cause rather than declare everything as being placebo or whatever.

Presumably the testing that shouldn't be mentioned in this forum is a cheap and reliable way to determine whether it is placebo or not  
More measurement on better equipment is of course nice too.

> I've often expected something to make no difference at all and found a difference for which I don't have an explanation for. 

well, I at some stage thought a $5 usb 2.0 spec certified cable made a difference over the one that came with my MD11... and I didn't expect a difference.
The problem is, MD11 transfers the data to the cypress usb chip in bulk mode with retransmission on error, so that's simply impossible. (I've also double checked and both transferred to external hdd devices at the same max/sustained data rate  )
So placebo is placebo


----------



## jackmccabe

The results of multiple null tests, to me prove there is absolutely no difference.
  These null tests even contain distortion due to the dac (although not converting) yet the still show there is no audible difference.
  Could someone please explain to me a reason why a null test would not prove there is no audible difference.


----------



## DaBomb77766

Quote: 





jackmccabe said:


> The results of multiple null tests, to me prove there is absolutely no difference.
> These null tests even contain distortion due to the dac (although not converting) yet the still show there is no audible difference.
> Could someone please explain to me a reason why a null test would not prove there is no audible difference.


 


  Magic.


----------



## Currawong

jackmccabe said:


> The results of multiple null tests, to me prove there is absolutely no difference *in his particular DAC*.
> These null tests even contain distortion due to the dac (although not converting) yet the still show there is no audible difference*in his particular DAC*.




FTFY.


----------



## jackmccabe

Quote: 





currawong said:


> Quote:
> 
> 
> 
> ...


 
  Why would it change with different dacs as in this case it is actually not doing any conversion?


----------



## Currawong

jackmccabe said:


> Why would it change with different dacs as in this case it is actually not doing any conversion?




I was thinking of his measurements of the audio output, which are below audible. However, for a better idea of some of what I'm talking about, track down Dan Lavry's posts about jitter and how it may affect the analog output of a DAC.


----------



## svyr

>track down Dan Lavry's posts about jitter and how it may affect the analog output of a DAC.

errr, isn't this a bit separate to effects of USB cables? (read em a while ago. Dan sure is courageous. He was getting flamed by n00bs  )


----------



## Steve Eddy

Quote:  





> Could someone please explain to me a reason why a null test would not prove there is no audible difference.


 

 For the same reason that no one having yet bagged a bigfoot proves there's no such thing as bigfoot.
   
  That's why it's called a null result rather than a negative result.
   
  se


----------



## Prog Rock Man

Quote: 





currawong said:


> You have to indeed be careful you aren't fooling yourself. I can only speak for myself when I say I've often expected something to make no difference at all and found a difference for which I don't have an explanation for. I think a better attitude to have is to find out the cause rather than declare everything as being placebo or whatever. Deciding on only one truth is not scientific, even if one's belief is related to science.
> 
> I think it is inside DACs that we will need to be looking for our answers though. Either we get someone to make measurements (I'm working on that) or this thread ends being being a bunch of audiophiles and non-scientists chest-beating their beleifs. Which do you reckon is better?


 



 I do have an explanation for why people find a difference. It is based on all of the evidence bearing in mind some of us have one hand tied behind our back with regards to the presentation of *all* of the evidence. From that I can decide on 'one truth'. I have made a very reasonable and defendable decision, how is that 'not scientific'? Based on the way you phrased the above, can anyone make a decision about anything?
   
  Even if you do get more measurements, how do you plan to link that to audibility? Which do you reckon is better, more measurements or more measurements and a link to audiblity?
   
  I am prepared to accept new evidence as it appears, but as it stands with all cables, USB included is that the difference is in the listener and not in the cable.


----------



## jackmccabe

Quote: 





steve eddy said:


> For the same reason that no one having yet bagged a bigfoot proves there's no such thing as bigfoot.
> 
> That's why it's called a null result rather than a negative result.
> 
> se


 

 Wait are you saying differences made by cable are like bigfoot, or are you criticizing null tests?
   
  Also why would you assume usb cables make audible differences with certain dacs and not with others;
  as this just seems illogical is it just so you can live in a fantasy reality where cables only make a difference in your system?


----------



## upstateguy

Quote: 





currawong said:


> You have to indeed be careful you aren't fooling yourself. I can only speak for myself when I say I've often expected something to make no difference at all and found a difference for which I don't have an explanation for. I think a better attitude to have is to find out the cause rather than declare everything as being placebo or whatever. Deciding on only one truth is not scientific, even if one's belief is related to science.
> 
> I think it is inside DACs that we will need to be looking for our answers though. Either we get someone to make measurements (I'm working on that) or this thread ends being being a bunch of audiophiles and non-scientists chest-beating their beleifs. Which do you reckon is better?


 

 This is a general comment:  It is my opinion and has been stated before.
   
  It's not so easy to tell the difference between comparable dacs.  It's also not so easy to tell the difference between comparable amps. 
   
  I should think that the differences between comparable usb cables has to be an order of magnitude less than the difference between amps and dacs.
   
  USG


----------



## Prog Rock Man

The way Steve Eddy and Currawong are arguing it is as if we risk fooling ourselves by deciding that bigfoot does not exisit having looked at all of the available evidence, whilst those who suggest he does exist ignore some of the available evidence, evidence which very much shows, bigfoot does not exist. 
	

	
	
		
		

		
			




   
  I am still open to new evidence, are you going to accept all of the existing evidence?


----------



## Steve Eddy

Quote: 





jackmccabe said:


> Wait are you saying differences made by cable are like bigfoot, or are you criticizing null tests?


 
   
  Neither.
   
  I'm simply pointing out that a null result is not the same as a negative result. It proves nothing one way or the other, hence, the term "null" which comes from the latin _nullus resultarum_ which means "no consequence."
   
  Quote: 





> Also why would you assume usb cables make audible differences with certain dacs and not with others;
> as this just seems illogical is it just so you can live in a fantasy reality where cables only make a difference in your system?


 
   
  I'm not making any such assumption.
   
  se


----------



## Steve Eddy

Quote: 





prog rock man said:


> The way Steve Eddy and Currawong are arguing it is as if we risk fooling ourselves by deciding that bigfoot does not exisit having looked at all of the available evidence, whilst those who suggest he does exist ignore some of the available evidence, evidence which very much shows, bigfoot does not exist.


 

 My only "argument" is pointing out that a null result proves nothing one way or the other. Just as not having bagged a bigfoot proves nothing one way or the other.
   
  se


----------



## vandaven

Quote: 





steve eddy said:


> Neither.
> 
> I'm simply pointing out that a null result is not the same as a negative result. It proves nothing one way or the other, hence, the term "null" which comes from the latin _nullus resultarum_ which means "no consequence."
> 
> ...


 

 Excuse me, but I don't seem to understand what you are talking about. I suppose the "nulling" refers to the tests I did by re-recording music and audio test sequences by using different USB cables (as variables) within the "signal" chain. The inverse summation (one signal reversed by 180°) of both usb cable recordings led to the result that there is no significant or measurable difference between a "high conductive expensive" usb cable and a "no-name" usb cable. It's kinda like 5 - (5 x -1) which equals zero. That is meant by nulling. ANY positive or negative result would have meant that one of the cables is of higher quality than the other. 

 If this is too hard to understand, I really do not know how to simplify it any further, but I am willing to try to propose explanations to anybody who doesn't get it.


----------



## upstateguy

Quote: 





jackmccabe said:


> Wait are you saying differences made by cable are like bigfoot, or are you criticizing null tests?
> 
> Also *why would you assume usb cables make audible differences with certain dacs and not with others;*
> as this just seems illogical is it just so you can live in a fantasy reality where cables only make a difference in your system?


 

 The general answer is that the greater resolution of the dac the more you can hear the difference between cables.
   


  Quote: 





prog rock man said:


> The way Steve Eddy and Currawong are arguing it is as if we risk fooling ourselves by deciding that bigfoot does not exisit having looked at all of the available evidence, whilst those who suggest he does exist ignore some of the available evidence, evidence which very much shows, bigfoot does not exist.
> 
> 
> 
> ...


----------



## Prog Rock Man

Quote: 





steve eddy said:


> My only "argument" is pointing out that a null result proves nothing one way or the other. Just as not having bagged a bigfoot proves nothing one way or the other.
> 
> se


 



 Not having bagged a bigfoot is only part of the evidence as to whether such exisits or not.
   
  How do you link your cables to audible differences in sound quality?


----------



## vandaven

Quote: 





steve eddy said:


> My only "argument" is pointing out that a null result proves nothing one way or the other. Just as not having bagged a bigfoot proves nothing one way or the other.
> 
> se


 

 Apparently you are not able to distinct between the analog world and a digital system, which is kinda "simple" in comparison. In the digital world, we have a fixed system with a certain number of samples and wordlenghts per second. In case of a digital CD, it's 44100 x 16 different bits of audio information per second. The mountains and woods, which are constantly changing shape (maybe at the speed of the Planck interval), offer lots of hiding places for Bigfoot, so he may hide there forever without being caught. If a DAC is not reacting to the bitstream accordingly, it's probably damaged.


----------



## jackmccabe

Quote: 





steve eddy said:


> Neither.
> 
> I'm simply pointing out that a null result is not the same as a negative result. It proves nothing one way or the other, hence, the term "null" which comes from the latin _nullus resultarum_ which means "no consequence."


 


  Wait your making an assumption that a test is useless based on its name? 
  Wow.
  Science as we know it currently states audio cables cannot make an audible change to the sound unless functioning incorrectly.
  As no one has yet to produce a single shred of evidence that suggest contrary.
  I personally find it ridiculous of someone to put what they "hear" over science and logic.
  Peoples minds are extremely easily tricked, so to assume that you are in fact correct and scientific tests are incorrect seems arrogant and silly.
  If someone can actually provide any (unbiased, reasonable) evidence that suggests there is a difference I would be gob smacked.


----------



## limpidglitch

Quote: 





vandaven said:


> Apparently you are not able to distinct between the analog world and a digital system, which is kinda "simple" in comparison. In the digital world, we have a fixed system with a certain number of samples and wordlenghts per second. In case of a digital CD, it's 44100 x 16 different bits of audio information per second. The mountains and woods, which are constantly changing shape (maybe at the speed of the Planck interval), offer lots of hiding places for Bigfoot, so he may hide there forever without being caught. If a DAC is not reacting to the bitstream accordingly, it's probably damaged.


 

 No reason to be condescending, Eddy's clever enough.
  It might have passed you right by, but you are in fact talking about two completely different things, both being applicable to the discussion here.
  You are talking about a specific testing protocol, often refered to as Null Difference Testing, used in the audio production world, and elsewhere. One famous example is the Carver Challenge, where Bob Carver used null testing to tune his solid state amplifier to sound perceptably identical to an expensive tube amplifier.
  On the other hand, what Steve Eddy is talking about is a Null Result, the only result you do not want from a scientific experiment, because it adds no useful data.
   
  Oh and PRM, there is no 'evidence' against a bigfoot, it's existence is just highly improbable. An almost infinite improbability factor, one might say.


----------



## Prog Rock Man

That depends on your definition of evidence. Mine is that it anything which can be used to prove or disprove something. Evidence to show 'proof' of bigfoots existence can be hoaxed, is part of the evidence that it does not exist.


----------



## Steve Eddy

Quote: 





limpidglitch said:


> No reason to be condescending, Eddy's clever enough.
> It might have passed you right by, but you are in fact talking about two completely different things, both being applicable to the discussion here.
> You are talking about a specific testing protocol, often refered to as Null Difference Testing, used in the audio production world, and elsewhere. One famous example is the Carver Challenge, where Bob Carver used null testing to tune his solid state amplifier to sound perceptably identical to an expensive tube amplifier.
> On the other hand, what Steve Eddy is talking about is a Null Result, the only result you do not want from a scientific experiment, because it adds no useful data.


 
   
  THANK YOU!
   
  se


----------



## Steve Eddy

Quote: 





prog rock man said:


> Not having bagged a bigfoot is only part of the evidence as to whether such exisits or not.


 

_Absence of evidence is not evidence of absence_ - Carl Sagan
   
  Quote: 





> How do you link your cables to audible differences in sound quality?


 
   
  Simple. I don't.
   
  se


----------



## Prog Rock Man

Lol, I might buy one of your cables Steve!
   
  That is a pithy response from Carl Sagan, but it is not applicable here as there is evidence to show the abscence of the ability of a cable to make a difference to sound quality.


----------



## jackmccabe

The thing is there is more evidence that suggests there are no audible differences between cables than there is to suggest that bigfoot doesn't exist.
  I am still contemplating whether it is an actual upgrade for a listener if they believe there to be a difference but there is actually not.
   
  Also if the listener truly believes that cables make an audible improvement so much that they "hear" one, then does it matter.
  Personally I like to live in an objective reality, but clearly others would prefer to live in the magical wonderland of subjectivity in which they can ignore science and reality.


----------



## Steve Eddy

Quote: 





prog rock man said:


> Lol, I might buy one of your cables Steve!


 

 Great! If you do, let me know and I'll give you our special curmudgeon discount. 
	

	
	
		
		

		
			




   
  Quote: 





> That is a pithy response from Carl Sagan, but it is not applicable here as there is evidence to show the abscence of the ability of a cable to make a difference to sound quality.


 
   
  Sure. But that evidence is NOT just null results from blind listening tests, which is the context of my comment.
   
  se


----------



## vandaven

By no means I want to be condescending.
   
  Maybe I overlooked a line, but who started talking about a NULL result?


----------



## Steve Eddy

It was my fault.
   
  I was replying to jackmccabe's post where he said "Could someone please explain to me a reason why a null test would not prove there is no audible difference."
   
  In hindsight I see now that he wasn't referring to a null result in a blind listening test.
   

   
  Sorry.
   
  se


----------



## Currawong

prog rock man said:


> I do have an explanation for why people find a difference. It is based on all of the evidence bearing in mind some of us have one hand tied behind our back with regards to the presentation of *all* of the evidence. From that I can decide on 'one truth'. I have made a very reasonable and defendable decision, how is that 'not scientific'? Based on the way you phrased the above, can anyone make a decision about anything?
> 
> Even if you do get more measurements, how do you plan to link that to audibility? Which do you reckon is better, more measurements or more measurements and a link to audiblity?
> I am prepared to accept new evidence as it appears, but as it stands with all cables, USB included is that the difference is in the listener and not in the cable.






prog rock man said:


> That depends on your definition of evidence. Mine is that it anything which can be used to prove or disprove something. Evidence to show 'proof' of bigfoots existence can be hoaxed, is part of the evidence that it does not exist.




I think your understanding of how science works, believing that it reveals absolute truths ('one truth' in your words) is grossly distorted. A person "prepared to accept new evidence" in something, doesn't say that they have decided on what is the truth, let alone going about trying to shove their belief (regardless of their being any validity in anything they say) down the throats of everyone in sight without any respect for others.

Since it seems I need to repeat myself to get it into your head, I have trouble believing that, despite, for example, Oyaide's evidence of their USB cables improving the form of the data signal, that it will make any useful improvement when used with a DAC, where it wouldn't be more effective to put the money towards a higher quality USB to S/PDIF interface, if not a better DAC with a better digital implementation and lower distortion instead. However, there isn't enough data out there with which people can make well-informed decisions IMO. If people can hold off on the religious arguments and we get more capable people obtaining good data that can be correlated with people's listening impressions (see Innerfidelity for the kind of thing I'm talking about) then we can provide some kind of benefit to people.


----------



## Prog Rock Man

'One truth' was in quotations because it was actually what you said Currawong!
   
  I do believe that science and nature have absolute truths, or as near as makes no difference, otherwise how do make any decisions? I believe that as it stands, the evidence is that cables inherantly make no difference. I will change that position if new evidence comes alone. I did that before and I will do it again.
   
  There is no need to be offensive about this, we disagree, you express your views, I express mine.
   
  Can you link to Oyaide's evidence re USB, I have searched their site abd cannot find anything? Thanks.


----------



## DaBomb77766

Quote: 





prog rock man said:


> 'One truth' was in quotations because it was actually what you said Currawong!
> 
> I do believe that science and nature have absolute truths, or as near as makes no difference, otherwise how do make any decisions? I believe that as it stands, the evidence is that cables inherantly make no difference. I will change that position if new evidence comes alone. I did that before and I will do it again.
> 
> ...


 


  While there may be "absolute truths" in nature, I doubt we'll ever find them - or at least, I doubt we'll ever find them precisely to the point of them being absolutely, infinitely true.


----------



## jackmccabe

No one has yet to give a valid reason as to why null tests do not prove usb cables do not make a difference.
  Yes we have had the explanation that it is only with the dacs used in the test, but I think that's utter rubbish.
  I cannot think of a way in which a usb cable would effect multiple dacs differently, it just makes no sense.
   
  I haven't found a single piece of evidence that suggests there is a difference, but I there is a lot to suggest there isn't a difference;
  so how could you come to the conclusion there is a difference based on any logical or rational though?


----------



## Prog Rock Man

Re absolute truths, I go by the legal ideals of beyond all reasonable doubt and balance of probablities. I would happily go to court and evidence beyond all reasonable doubt that cables inherantly make no difference.
   
  I also don't buy the idea of USB cables affecting different DACs differently, but will wait testing to make a firm decision on that one.


----------



## DaBomb77766

I still think it would be interesting to see how far you could extend a cable before it starts to give you errors...and even more interesting to see how far you could extend an "audiophile" cable until it gives you errors, though such a test would probably be prohibitively expensive.


----------



## jackmccabe

Quote: 





dabomb77766 said:


> I still think it would be interesting to see how far you could extend a cable before it starts to give you errors...and even more interesting to see how far you could extend an "audiophile" cable until it gives you errors, though such a test would probably be prohibitively expensive.


 
  You could definitely go 5m+, as the spec for usb 2.0 is 5m maximum length.


----------



## Currawong

Do any of you know, even slightly, how a DAC works?


----------



## svyr

currawong said:


> Do any of you know, even slightly, how a DAC works?




I do =), doubtful  ? (at least 3 designs past the USB stage, till the DAC chip. And a bit about what's going on inside the chip too). Anything in particular you'd like to share with the class  ? 

Yes it's possible the artifacts are below the noise floor of his DAC. Yes it's also possible that the resolution of the pic posted doesn't show 1-2 samples dropped as errors here and there. (with 44.1k samples a second and god knows how many seconds in that graph)


----------



## jackmccabe

Quote: 





currawong said:


> Do any of you know, even slightly, how a DAC works?


 

  
  Yes, but it was performing no conversion.
  I f a usb cable were to make a difference there would have to be some audible degradation in the signal.
  The amount of distortion that would have to be induced by the cable would have to be huge >1%.
  Amps and dacs generally don't induce this much distortion so how the heck do you think a cable would.
  Also vandaven's dac would have to be magic to turn >1% of distortion into absolutely minute amounts of distortion.
   
  There is also no need to be patronising, if anything I should be patronising you for believing in something without a shred of evidence,
  because all you keep doing is criticizing the evidence we provide rather than providing any evidence that supports your viewpoint.


----------



## DaBomb77766

Quote: 





jackmccabe said:


> You could definitely go 5m+, as the spec for usb 2.0 is 5m maximum length.


 


  Yeah, though for audio purposes alone the cable isn't transmitting much data...so it should probably be able to go a bit further before it starts to get noticeable distortion.  Then again, there is no error correction for most DACs, so I'm not sure how long it would be able to get before it starts to lose bits.  But still, a 5 meter cable, at the prices that some cable manufacturers are selling at, would be ridiculous.  Locus's flagship USB cable starts at $3549 for 3 feet...


----------



## drez

Science cannot provide absolute truths, however it can provide us with various levels of useful or instrumental truths.  It can provide insights into practical limits which are measurable and repeatable, as well as insights into what is not measurable and repeatable.
   
  My problem is that *many* cable manufacturers show a shocking lack on insight into the scientific principles they supposedly employ to design their products.  Academics commonly rip the scientific principles and processes brought up in these "white papers" to pieces.  The theories and practices set out in the papers I have come across are neither to academic nor professional standards of practice.
   
  I have no problem with companies like Grado where John designs his products by ear.  None of the claims he makes are unreasonable, and the differences between his products are verifiable.
   
  Digital cables are a purely technological product which operate in a purely technical manner.  Transfer of digital signal AFAIK is no some uncharted branch of science.  Yes oscilloscope plots are useful measurements of digital signal transmission, but these need to be interpreted by someone with a knowledge of engineering, taking into account the required jitter tolerances of the interface.  Also take into consideration that most DAC's reclock the digital signal, so the jitter from the USB interface is not transferred to the DAC.  This is AFAIK why so many USB to SPDIF converters exist.  These devices are there precisely to ensure that we don't need super expensive USB cables, only ones that meet the jitter tolerances of the given USB receiver chip at any given sampling rate.  After than any further jitter reduction is totally wasted as it won't affect the performance of the DAC at all (the signal is reclocked, remember?)
   
  Now if someone were to publish some standards for the jitter, like for instance the TE7022 data sheet (I cant find it DX"), then we would be able to say with some certainty that the USB cable used must be able to transmit a signal with a certain jitter tolerance, then we could go out and find a cable that meets or exceeds this tolerance.  And instead of showing us an oscilloscope measurement, they could give us jitter measurements in nanoseconds etc produced by the very same test setup.
   
  This is not magic, but cable manufacturers want to confuse us in order to hide the frightening lack of rigor in their design processes, and quite possible the redundancy of their products given the designs of any half decent DAC or SPDIF converter.


----------



## jackmccabe

Quote: 





dabomb77766 said:


> Yeah, though for audio purposes alone the cable isn't transmitting much data...so it should probably be able to go a bit further before it starts to get noticeable distortion.  Then again, there is no error correction for most DACs, so I'm not sure how long it would be able to get before it starts to lose bits.  But still, a 5 meter cable, at the prices that some cable manufacturers are selling at, would be ridiculous.  Locus's flagship USB cable starts at $3549 for 3 feet...


 

 It is a timing issue http://www.usb.org/developers/usbfaq/#cab1


----------



## svyr

>like for instance the TE7022 data sheet 

tenor/gfic aren't big on data sheets. Who needs datasheets  ? (only analog, bb, TI, etc...) http://www.gfec.com.tw/word_file/TE7022PB-v14.pdf - that's as close as you're going to get to one. 

Look, stop flaming each other for a bit, and let Tyll, or whoever it was Currawong was referring to measure it with a better DAC (Yes it's possible the artifacts are below the noise floor of his DAC. Yes it's also possible that the resolution of the pic posted doesn't show 1-2 samples dropped as errors here and there. (with 44.1k samples a second and god knows how many seconds in that graph)).

Even better, chip in $100 for a hardware usb debugger, send the cable to that guy and a have a look whether there's any difference in the data going into one end of the normal and audio-pedophile cable  

In the meantime, use a software usb debugger and a usb mass storage device + those cables and see whether sending data to a usb device in bulk mode gets any difference (pretty sure for bulk mode (only, not audio sync/async or adaptive modes) retransmission on errors will be requested from the host, not the controller cache, since it's possible USB cable was the cause, so you'll see a 'faulty' cable having transferred more packets across than a to spec one)


----------



## uelover

Quote: 





currawong said:


> Do any of you know, even slightly, how a DAC works?


 


  Hey Currawong,
   
  Save your breath and time for something more useful (i.e., listening to music, playing with children, etc). You will be surprised at how many people think (and thus believed and are convinced) that they knew and understood everything.


----------



## drez

Quote: 





uelover said:


> Hey Currawong,
> 
> Save your breath and time for something more useful (i.e., listening to music, playing with children, etc). You will be surprised at how people think (and thus believed and are convinced) that they knew and understood everything.


 

 Would you trust a someone who knew nothing about how a computer performs to buy you a computer?
	

	
	
		
		

		
			




   
  Say someone with a little knowledge might think that an AMD athlon is better than than an Intel core i7 because it has more cores and a higher frequency clock?
   
  How about if the manufacturer appeared to know nothing about how a computer works?
   
  I don't trust myself tbh, not because I think I know everything, but because I am aware of how little I know, and also how little cable manufacturers seem to know (or want us to know).
   
  Resigning that one cannot have a practical level of knowledge in order to guide one's decisions smacks a little of ignorance though?


----------



## jackmccabe

Quote: 





svyr said:


> Look, stop flaming each other for a bit, and let Tyll, or whoever it was Currawong was referring to measure it with a better DAC (Yes it's possible the artifacts are below the noise floor of his DAC. Yes it's also possible that the resolution of the pic posted doesn't show 1-2 samples dropped as errors here and there. (with 44.1k samples a second and god knows how many seconds in that graph)).


 
  If anything the condition of the previous tests was more likely to make a difference due to the "worse" dac used which should induce more noise and distortion.
  It also doesn't matter if you can't see certain errors as I assume vandaven listened to it and found no audible noise.


----------



## DaBomb77766

Quote: 





jackmccabe said:


> It is a timing issue http://www.usb.org/developers/usbfaq/#cab1


 


  In that case, I wonder how the timing issues would affect audio at all...?  After all, it's just a one-way data stream and neither end cares whether or not all of the data gets there, so I'm not sure if timing issues would have a major effect on an audio signal.  Not sure though, but the best way to find out is to test it...all you'd need is a whole bunch of USB extension cables plus a normal testing rig.


----------



## svyr

jackmccabe said:


> *If anything the condition of the previous tests was more likely to make a difference due to the "worse" dac used which should induce more noise and distortion*.
> It also doesn't matter if you can't see certain errors as I assume vandaven listened to it and found no audible noise.




that sounds reasonable.


----------



## I3eyond

I'll be honest, I just upgraded the USB interconnect between my computer to my Musical Fidelity V-DAC to an Audioquest Cinnamon cable, and I can honestly say I can hear a slight difference.  
   
  Is it worth the extra money?  Probably not.  Honestly, I picked this cable up because my entire setup is red, including my computer lighting, keyboard illumination, border of my mousepad, and my Audioquest Sidewinder RCA interconnects from my DAC to my amp.
   
  A serious question though, is it possible for a "better" cable to be more revealing of flaws in the music, in the recording?


----------



## throzen0303

If I want a black cable that means I have to used the original or get the Carbon LOL which is about the same price as my 8740 DAC, I will get some 20awg USB cable for like 10$ instead
  Quote: 





i3eyond said:


> I'll be honest, I just upgraded the USB interconnect between my computer to my Musical Fidelity V-DAC to an Audioquest Cinnamon cable, and I can honestly say I can hear a slight difference.
> 
> Is it worth the extra money?  Probably not.  Honestly, I picked this cable up because my entire setup is red, including my computer lighting, keyboard illumination, border of my mousepad, and my Audioquest Sidewinder RCA interconnects from my DAC to my amp.
> 
> A serious question though, is it possible for a "better" cable to be more revealing of flaws in the music, in the recording?


----------



## Hennyo

screw YES. Forest is a big imporovement over stock cable. (I found) HOWEVER, You will be happier with Cinnamon and CARBON is the best bang/buck in the line by far. It effing rocks to jam too.
   
   
You should buy all three and return the two you don't like, no harm done. I'd appreciate somebody else supporting my claims.
  =D Please report back your results. There are many here who would benefit. 
  
  Quote: 





throzen0303 said:


> Can't believe the amount of people reply to my post@.@ Learning my way though,
> Should I invest into a AudioQuest Forest USB for $30(1.5m), to my $140 DAC(Custom Build)


----------



## Hennyo

Quote: 





9pintube said:


> In my system the USB cable from the iMac into the John Kenny Mod Hi Face makes no difference, ( and I'm a Cable believer)!!!   Fellow Head-Fi'er Bubu1 and I  realized the USB cable isn't using any power (from the mac) and therefore any good USB cable with "this system" will work fine, Remember it's just "info" being sent through the cable to the JK Hi-Face! ..... So have you noticed the adds for the big buck USB cables, most show their cross sectioned design and that shows the power and the signal that make up the USB design is separated in the cables dielectric, making a difference, in other systems.. Remember, that equates to more $$$ in making those USB cables.......Now after coming out of the Hi-Face the cables, be it, a 75ohm digital or a true 75ohm BNC into mine/ours or your Dac matter BIG TIME If you can't hear a difference then well what can i say........      But for guy's like *throzen0303, *who is going from source straight into his Dac There could and should be a difference with a well built and well designed USB cable when used in this apt.   But, I'd listen 1st to the big buck cables if at all possible... This is JMO and what I hear, I'll even include what Tom heard....also... Believe me we've tried several in both of our systems......   Cables do make a difference when matched with your other components........


 


 You rock. And yes, cables of any kind make the leaps and bounds of difference, second only to a better phone/much higher end amp/dac. Very happy people are starting to see the light.


----------



## Hennyo

Quote: 





t-h-e-p-i-m-p said:


> http://www.referenceaudio.se/ImageUpload/Nordost/Blue-Heaven-LS-USB.jpg
> 
> great usb cable! i compared it to some random no-name usb cable. And there is a pretty big noticeable different between them!


 

 Thanks for sharing! *Dramatic voice* NOW "NON-BELIEVERS", GO FORTH AND REVEL IN OPTIMUM AUDIBLE EXPERIENCE !!! 
	

	
	
		
		

		
			




   
   ENJOY, !!!! 
	

	
	
		
		

		
		
	


	


And remember to PLEASE REPORT BACK!


----------



## Hennyo

Quote: 





currawong said:


> I've found one better, which is someone with the calibre of gear capable of measuring digital equipment down to femtoseconds. However, regardless, if we take those measurements Oyaide did of their USB cable, we don't know how the DAC it is used with will be affected or not without knowing enough about and measuring the DAC's performance. It's not something, I think, that can be generalised as being all nonsense or all genuine as different electrical circuits don't behave the same way. Some useful data, _per DAC_, is much needed though. Other than that, I'm not a big fan of the idea of expensive USB cables unless one already has spent a considerable amount of money on (genuinely high quality) digital gear relative to their cost. However it shouldn't matter by then anyway.
> 
> As for what is audible, if our eardrums can detect movement of as little as 5 angstroms (equivalent IIRC to someone dropping a pin on tarmac a few miles away) then I'm not going to write off everything below any supposed cut-off as inaudible. On one of the online sites where you can test your hearing, you listen to sine waves at different frequencies which are different from about 1dB down to about 1/16th dB. However the site also has the same tests using square waves, which are far easier to determine the differences between, depending on the frequency being tested. Considering that everyone's hearing ability is different at different frequencies, dependant on the waveform, the type of music, the noise floor of the gear used and how that gear is affected by its digital input electrically and any jitter and how that tonally distorts the sound if at all (see what Dan Lavry wrote in another thread about the effects of jitter), the most one might say is that something is unlikely to be audible. This goes for any equipment, not just cables.
> 
> Arguing about whether or not, in this case, expensive USB cables are nonsense or not is actually doing people a disservice. Finding some useful answers that will help people determine if purchases are good value or not, eg: if their DAC will benefit from, say, a higher quality USB to S/PDIF converter (I'm not going to suggest USB cables to someone personally, at least not without their having a worthy cost/performance improvement that is undoubted) and at what point the price/performance ratio suggests they should just spend the money on better gear I think is considerably more valuable.


 


 It is undoubted. It's Worth 100$ difference for a cable if it makes at least a 100$ difference in your system. There is no denying that. They do make a difference and once you do hear the improvement, you cannot unhear it. You will not want to listen without it. It it NOT placebo and it is NOT a false reality. There are plenty here who've shared their experiences with usb recable. It DOES make an UNDISPUTABLE difference. If you're STILL saying it does not.............................. You are only starving yourself. Once you've tried it you're welcome to come back and troll, but until then, there are _plenty_ of accounts in favor of signal cable improvements and differences - of any kind -
   
  You can't make this stuff up. Nobodies that daft
   
  TRY:
  READ:
  AND WEEP (for unrestrained _JOY_!!)


----------



## Currawong

Quote: 





jackmccabe said:


> Yes, but it was performing no conversion.
> I f a usb cable were to make a difference there would have to be some audible degradation in the signal.
> The amount of distortion that would have to be induced by the cable would have to be huge >1%.
> Amps and dacs generally don't induce this much distortion so how the heck do you think a cable would.
> ...


 

 Well, first of all, you and Prog Rock Man are like broken records, wanting to post about one thing and one thing only (which you can't). Second, you're making me as saying I believe is completely different to what you make it out that I believe.  The OP asked a question, I am trying to steer you guys towards an actual answer, not speculation based on reading stuff online.  The impression I get from your posts is of someone whom a: doesn't know how digital conversion works, and b: has a typical warped idea of what "audible" means, including thinking that there are absolutes about what people can hear and what they can't and c: doesn't understand how science works or what experiments achieve either.
   
  I honestly doubt you could explain what I think, despite my having posted it at least three times in this thread.  Again, we are in a position to get some measurements and some answers -- very likely an answer that people with a sufficient degree of experience and common sense about their audio purchases know already, which, IMO, is that "audiophile" USB cables don't make a significant difference with most gear, if any at all, to be worth bothering with.  But knowing for sure beats chest-beating on the net.
  
  Now the question is, do you want me to ask someone nicely to do some measurements for us (he's probably interested) or are you just more interested in arguing?


----------



## Hennyo

Quote:


> Just speculating... There must be some logical reason why people say there are audio differences... Transmitting 1s and 0s through different mediums can't make the sound warmer or clearer or increase the soundstage. So what exactly is the difference that people hear?


 

 Exactly: but it does! This is too silly. Try it.
   
  PERIOD
   
  I said it once and I'll say it again, Digital Audio is not the same way as Digital Video. Sit here and complain all you want, but you're only starving your ears. 
	

	
	
		
		

		
		
	


	




 You'll s*** yourself when you eventually try it. It doesn't even cost that much. ::~TAKE A POT SHOT ~:: and report back your findings! Valiant People here have said their bit. Quit chastising > condemning they who are happy with their findings. _These people naturally want to share their happiness with others. That's why we're all here!_
   
  Another example: I now use an AQ Optilink-1 over the 30$ best buy fiber optic cable. Much higher quality fiber = less loss or distortion of the data, or light, as it passes through.
  The result is a much more cleanly sound, everything is just more distinct, and as a result of this, imaging on my speakers has become much more defined - Left to right and North to South, but especially deeper soundstage.


----------



## Hennyo

Quote: 





currawong said:


> Well, first of all, you and Prog Rock Man are like broken records, wanting to post about one thing and one thing only (which you can't). Second, you're making me as saying I believe is completely different to what you make it out that I believe.  The OP asked a question, I am trying to steer you guys towards an actual answer, not speculation based on reading stuff online.  The impression I get from your posts is of someone whom a: doesn't know how digital conversion works, and b: has a typical warped idea of what "audible" means, including thinking that there are absolutes about what people can hear and what they can't and c: doesn't understand how science works or what experiments achieve either.
> 
> I honestly doubt you could explain what I think, despite my having posted it at least three times in this thread.  Again, we are in a position to get some measurements and some answers -- very likely an answer that people with a sufficient degree of experience and common sense about their audio purchases know already, which, IMO, is that "audiophile" USB cables don't make a significant difference with most gear, if any at all, to be worth bothering with.  But knowing for sure beats chest-beating on the net.
> 
> Now the question is, do you want me to ask someone nicely to do some measurements for us (he's probably interested) or are you just more interested in arguing?


 
   
  Shattered = > broken records. Although it does seem like anyone who's "been there, done that" has LOVED it, and has been happily a' honeymooned for quite some time with their cable > sound system > experience. I just think it's sad that people are still claiming "NO DIFFERENCE, RAAWWWRRR," at this point/after all that has been said these people are just trolling.
  Get those try-hard pants on! 
	

	
	
		
		

		
		
	


	




 It's becoming pitiful.
  
  Quote: 





prog rock man said:


> I do have an explanation for why people find a difference. It is based on all of the evidence bearing in mind some of us have one hand tied behind our back with regards to the presentation of *all* of the evidence. From that I can decide on 'one truth'. I have made a very reasonable and defendable decision, how is that 'not scientific'? Based on the way you phrased the above, can anyone make a decision about anything?
> 
> Even if you do get more measurements, how do you plan to link that to audibility? Which do you reckon is better, more measurements or more measurements and a link to audiblity?
> 
> I am prepared to accept new evidence as it appears, but as it stands with all cables, USB included is that the difference is in the listener and not in the cable.


 
  I'm truly sorry for you. For real.


----------



## uelover

I am quite curious to try out Audiophilleo 1.
   
  Currently my WW Starlight is making a significant impact on my set up, more than what I like, because my initial plan to get Audio-GD DI was to negate the need for a good USB cable. It is USD89 so the damage to my wallet is still well contained.
   
  someone else who owned DI has just found the same thing.
   
   
  And yes, I would like to see someone explaining why an USB cable will affect SQ rather than wasting my time reading condescending posts repeatedly being posted here that 1) does not contribute anything to this community and 2) outright condemned empirical findings of others through warped 'scientific' beliefs of their own.
   
  People just like to making exaggerated ignorant claims to beat others just to serve their own egos don't they =)


----------



## Hennyo

Well, ty for posting your findings.
  People are afraid of what they don't understand. Concretely demonstrated over the last 20-x pages. I think we've established through consistent finds by (experienced on the matter) average joes (including yourself) that the difference is rather enjoyable. 
	

	
	
		
		

		
		
	


	




 And definitely real. 
   
  Fortunately this thread is finally starting to point in some direction: "post your experienced conclusion thread." If this accursed rampant thread has done nothing else, it has proved that cable upgrades do make a difference.
   
  ^^ Albeit it was a p.i.t.a to come to this conclusion.
   




 somestranger26
 Location: Somewhere in California
 
  Today I received a 2m Wireworld Ultraviolet USB cable to use with the digital interface, and I find it to be a nice addition to my system. It adds clarity and definition to the bass, and makes the treble smoother/less harsh (some harshness was introduced with the hex inverter upgrade). Didn't think a USB cable would matter, but it makes a difference about on par with the DI.
   
  Hennyo: This thread is really starting to ROCK. Love it. :*) THE MYTH IS BEING DISPELLED!!!!!!!
  Quote: 





uelover said:


> I am quite curious to try out Audiophilleo 1.
> 
> Currently my WW Starlight is making a significant impact on my set up, more than what I like, because my initial plan to get Audio-GD DI was to negate the need for a good USB cable. It is USD89 so the damage to my wallet is still well contained.
> 
> ...


----------



## jackmccabe

Quote: 





currawong said:


> Well, first of all, you and Prog Rock Man are like broken records, wanting to post about one thing and one thing only (which you can't). Second, you're making me as saying I believe is completely different to what you make it out that I believe.  The OP asked a question, I am trying to steer you guys towards an actual answer, not speculation based on reading stuff online.  The impression I get from your posts is of someone whom a: doesn't know how digital conversion works, and b: has a typical warped idea of what "audible" means, including thinking that there are absolutes about what people can hear and what they can't and c: doesn't understand how science works or what experiments achieve either.
> 
> I honestly doubt you could explain what I think, despite my having posted it at least three times in this thread.  Again, we are in a position to get some measurements and some answers -- very likely an answer that people with a sufficient degree of experience and common sense about their audio purchases know already, which, IMO, is that "audiophile" USB cables don't make a significant difference with most gear, if any at all, to be worth bothering with.  But knowing for sure beats chest-beating on the net.
> 
> Now the question is, do you want me to ask someone nicely to do some measurements for us (he's probably interested) or are you just more interested in arguing?


 
  No need to be patronising, I understand perfectly well how a dac works.
  ALos why do you continually just state that what I am saying is wrong rather than actually provide the explanation or any evidence.
  Also people cannot hear distortion under 1% http://en.wikipedia.org/wiki/Total_harmonic_distortion and that is just THD.
  Also I am not concerned with measurements as I believe that there is easily enough data to come to a valid conclusion.
   
  To be honest you seem to be the one that has an issue comprehending dacs and how they function.
  They cannot repair distortion of >1% it is impossible, either through reclocking or ASRC.
  Yes certain dacs may respond differently to different cables but the differences will be minute.
  All I ask for is one piece of evidence that suggests that there is  difference between usb cables and then I will reconsider my opinion,
  but until then all the claims of cables making are based on self-interested, bias and ignorant claims.


----------



## Hennyo

This guy is ridiculous. Jackmccabe: Check <<<< 24 pages and let the ppl come to their own conclusion. Why do you HAVE to ruin it for everybody else?! This is supposed to be an _informative _thread. either say something productive, or LEAVE.. (the thread alone).
   
Valiant people have demoed and made their claim to fame. You've never tried and hence should not be able to comment. Why should your opinion trounce theirs? What kind of audiophile are you? Hush puppy.
   
   0 experience, 0 right to speak on the matter. Now hush puppy. Your ego is deflating. Shattered records are no fun.
   
  Quote: 





jackmccabe said:


> No need to be patronising, I understand perfectly well how a dac works.
> ALos why do you continually just state that what I am saying is wrong rather than actually provide the explanation or any evidence.
> Also people cannot hear distortion under 1% http://en.wikipedia.org/wiki/Total_harmonic_distortion and that is just THD.
> Also I am not concerned with measurements as I believe that there is easily enough data to come to a valid conclusion.
> ...


----------



## Steve Eddy

*click*
  CLEANUP, AISLE NINE, CLEANUP, AISLE NINE.
  *click*
   
  se


----------



## Yoga Flame

Quote: 





> Originally Posted by *Currawong* /img/forum/go_quote.gif
> 
> [...]
> 
> Now the question is, do you want me to ask someone nicely to do some measurements for us (he's probably interested) or are you just more interested in arguing?


 

 I for one welcome having more objective measurements. It shouldn't matter whether or not we think a better digital cable can make an audible difference with a DAC. If a cable performs measurably better at transmitting digital data, that's a good thing to know. At the very least, we can use it over longer lengths than the standard USB spec allows for.


----------



## uelover

Quote: 





hennyo said:


> Are we allowed to say "s**u" here? This guy is ridiculous. Jackmccabe: Check <<<< 24 pages and let the ppl come to their own conclusion. Why do you HAVE to ruin it for everybody else?! This is supposed to be an _informative _thread. either say something productive, or LEAVE.. (the thread alone).
> 
> Valiant people have demoed and made their claim to fame. You've never tried and hence should not be able to comment. Why should your opinion trounce theirs? What kind of audiophile are you? Hush puppy.
> 
> 0 experience, 0 right to speak on the matter. Now hush puppy. Your ego is deflating. Shattered records are no fun.


 

 Chill Hennyo. This is not a place to show who is the right guy and who is the wrong guy by arguments.
   
  I believe the general consensus of those who owned a good USB cables already speak volumes.
   
  No need to response to cynics. At the end of the day, it is us who get to enjoy all the spoils =)


----------



## jackmccabe

Ummm, I have demoed and owned loads of usb cables, in fact I used to believe they made a difference.
  I have performed many rigorous listening tests and come to my conclusion.
  I test with both my ears and science.
  Also I am informing people of the "facts", providing my opinion and supporting it with evidence, I believed this was the point of the thread.
  You on the other hand have just come along and said there is a difference because you "hear" one.
  Your mind is easily fooled and tricked by marketing, visual stimuli and self-interest,
  so I cannot understand why you base your conclusion on what you "hear".
  You have zero proof, I would be happy to change my mind if you can provide some evidence to back up your belief.


----------



## Hennyo

Right you are =) Never a truer post.
   
  Quote:


uelover said:


> Chill Hennyo. This is not a place to show who is the right guy and who is the wrong guy by arguments.
> 
> I believe the general consensus of those who owned a good USB cables already speak volumes.
> 
> No need to response to cynics. At the end of the day, it is us who get to enjoy all the spoils =)


----------



## upstateguy

Quote: 





jackmccabe said:


> *The thing is there is more evidence that suggests there are no audible differences between cables than there is to suggest that bigfoot doesn't exist.*


 

 There is more anecdotal evidence to suggest to suggest Bigfoot exists than there is to suggest there is a difference between cables. <---- just saying
   

  Quote: 





currawong said:


> .....I have trouble believing that, despite, for example, *Oyaide's evidence of their USB cables improving the form of the data signal,* ..........


 

 I'm sorry A.  
	

	
	
		
		

		
		
	


	




  I'm very skeptical of any manufacturer's claims.
   
  E


----------



## DaBomb77766

Honestly, if you ask me, this thread has now degraded into posts that are indistinguishable from that of a religious fanatic - just replace a few words here and there and that's pretty much it.


----------



## upstateguy

Quote: 





dabomb77766 said:


> Honestly, if you ask me, this thread has now degraded into posts that are indistinguishable from that of a religious fanatic - just replace a few words here and there and that's pretty much it.


 


  I don't think it has degraded that much, but there could be better use of the multi quote feature.


----------



## uelover

Quote: 





upstateguy said:


> I don't think it has degraded that much, but *there could be better use of the multi quote feature.*


 


  Lol this is one of the best post here!


----------



## Hennyo

Quote: 





upstateguy said:


> I don't think it has degraded that much, *but there could be better use of the multi quote feature*.


 
   
  Haha!
   
	

	
	
		
		

		
			





oops
	

	
	
		
		

		
		
	


	




Yea, that was regretful. Just read so many great posts, it was an unethical typing frenzy. I apologize.


----------



## drez

"Don't get *WHY* "audiophile" USB cables would improve sound quality"
   
  This is the title of the thread.  There are 3 types of responses here: 1) From my experience it works but I don't know why 2) a-priori arguments why it shouldn't work 3)Suggested ways to test and verify that they do work through empirical measurement.
   
  To me the second two are the only ones actually addressing the question raised by the OP.
   
  I am a very skeptical person, no matter what I am buying, I seek reliable independent verification that the product performs as verified, however this comes unstuck when purchasing audio gear.  Therein lies the problem - I am resigned to purchase audio gear based off reviews and opinions, but I am skeptical of cable manufacturers as they don't seem technically or professionally proficient in the way they market their products.
   
  Pro-audio gear always comes with detailed specifications and performance data, however the same gear, when marketed exclusively to audiophiles is usually completely devoid of specifications or performance data, and often is described and marketed in misleading and just plain incorrect terms.  When specifications and performance data are provided, these are insufficient to make a proper assessment.  Compare for example the power conditioners from Oyaide with those from Furman - as an audiophile brand Oyaide doesn't publish any meaningful specs or performance data.  We don't know how it works or if it works, or the degree to which it works.  At the same time audiophile companies often make outrageous claims without any evidence to back them up, and we pay for these dubious technologies.
   
  I cannot say for certain that USB cables make no difference, but I detest the fact that audiophiles are treated like idiots and fed the rubbish marketing that we are given.  When an USB cable is presented in a professional and technically proficient manner, I will buy it.


----------



## svyr

>Now the question is, do you want me to ask someone nicely to do some measurements for us (he's probably interested) 

Do ask Tyll...


>Well, first of all, you and Prog Rock Man are like broken records, wanting to post about one thing and one thing only

So is Hennyo. And with annoying formatting and triple posts


>I'm sorry A. I'm very skeptical of any manufacturer's claims.

+1 on claims, +1 on lack of interpretation for that graph and who knows whether the USB chip even cares about those things (below the acceptable variability for it)


----------



## uelover

Quote: 





drez said:


> "Don't get *WHY* "audiophile" USB cables would improve sound quality"
> 
> This is the title of the thread.  There are 3 types of responses here: 1) From my experience it works but I don't know why 2) a-priori arguments why it shouldn't work 3)Suggested ways to test and verify that they do work through empirical measurement.
> 
> ...


 

 Audiophiles can be treated like idiots by the manufacturers but it is the audiophiles themselves who can choose to not be treated like one.
   
  Like I said, I don't rely on nor fully trust spec sheets on the items that I buy, be it pro or non-pro audio items. I will not even believe a 99.9999% pure silver analogue cable to be that pure. But if it sounds much better than a USD10 cable and the price is low, why do I really care? Unless the cable costs me USD200 then I will have a case to be concerned.
   
  However, we need to be clear of the difference between 'make-believe' and 'reality'. Marketing hypes and the so-called 'professional' reviews is only worth that much. There have always been many hyped up reviews on newly released products (amplifier, headphones, dac, speakers) which got buyers all excited but ended up with disappointment after they have purchased them.
   
  People know and can decide for themselves whether the item they bought is really worth their money and worth keeping. So you guys gotta stop treating other head-fiers around here like idiots who needs 'enlightened' souls here to teach them how the universe works.


----------



## justanut

Maybe I should frame it differently then... for the benefit on Hennyo who would fit in with the term "fanatic" if any would.
   
  I don't hear a difference using USB cables of different "quality". The believers will say its because I don't BELIEVE in them causing a difference... reverse-placebo? Just like how the non-believers say you hear a difference because of placebo.
   
  Since we're at an impasse, the only logical solution is of course to take actual measurements. Its like giving you 2 identical/similar coins, one from 1980 and one from 2000 and asking which is heavier. There's bound to be a 50% split in opinions. In the end we weigh them to find out whats the scientific answer?
   
  The brain is amazing. Miracle potions worked because people believed in them. People die from simple ailments because they refuse to believe medicines work. Women can show symptoms of pregnancy from just believing they are... the list goes on.
   
  Seems like this will become another of those audiophile myths that will always have its fair share of believers and non-believers.
   
_The binary 1111 (decimal 15) becomes 7, 11, 13 or 14 when any of the 1s becomes a 0. It doesn't become a 15 or a 15..._


----------



## Hennyo

Quote:


> >Well, first of all, you and Prog Rock Man are like broken records, wanting to post about one thing and one thing only
> 
> So is Hennyo. And with annoying formatting and triple posts


 
   
  Quote:  
   
  Firstoff, you did not COMPLETE Currawong's quote, thereby misrepresenting information. Also, I post on MANY things, and have explained myself thoroughly for the community. Stubborn children will be stubborn children. Why are you attacking me for going out of my way, posting _lots _of information that has not yet before been posted?
  
  Oh, and Hennyo's actually tried cables, so HAI there. Oh, I've also tried my best over like 50 posts to reach out and share how cables sound with the community. And the differences/preffered pairings they make. Everyone's a 'noob' regarding given subjects. I'm sorry you cannot comprehend a cable making a difference.
   
  Also, how much more proffessional can it get?!?!?! I mean _really_?!?! They give specs on each box/retail package, describing every ounce of detail that's put into the cable. Audiomakers on their websites also explain the differences scientifically that their cables make. I've posted sources before in this thread. Did you not see it, or am I a broken record? Or are you just *blind? *
   
  Also: People seem to agree that these companies are onto something. (Get a room with you-know-who). Let people decide for themselves, so far clearly and nearly unanimously people have reported radical differences and/or improvements in their sound. What more do you want?!?!?!?! If you're interested, why don't YOU go look it up?! Isn't there enough proof to justify a fun little experiment for yourself? If you don't like it, then return it. I'm not going to sit here explaining something to a brick wall all day, so "walk off."
   
  We're trying to diagnose it, sorry there are no Frequency response graphs for cables as that would just be obsurd and pretty impractical to do. If not impossible to accurately represent system to system or headphone to headphone. I also intelligently counter your 'points,' every time. You're asking for information that either does not exsist, or does not accurately apply to a cable.
   
  Cablemakers realize people (myself included) are skeptical, and they do try their best to help the customer buy what's right for them.
   
  I'm somewhat distraught because a great number of others and myself go out of our way, trying to help the community, buy cables, unanimously report back our findings, and are then treated like proverbial sh** by the likes of you?! Somebody who's got a concrete cap on their head? Come on man, let in an idea every once in a while. Think entrepreneurial, outside the box, adventure, improvement, _Competitiveness_.
   
  Thanks for contributing. You've had enough proof. Shoe-shoe
  Quote: 





drez said:


> "Don't get *WHY* "audiophile" USB cables would improve sound quality"
> 
> This is the title of the thread.  There are 3 types of responses here: 1) From my experience it works but I don't know why 2) a-priori arguments why it shouldn't work 3)Suggested ways to test and verify that they do work through empirical measurement.
> 
> ...


 

 Ok, then remain skeptical: that has its downsides and upsides, like any other character trait. Remember that at some point I was very skeptical about this too. But then I demoed by chance while picking up an HDP. And the fun-adventurous 18y/o me wanted more for fun! (And to reach what I consider top-notch sound)
   
  Cables come with about the same amount of information as pro headphones do, so time to buck up your argument. Cable manufacturers also try to explain the differences their cables can make in Laman terms, so as not to sound as if on a high perch. There are somewhat technical explanations too, engineering explanation in Laman terms. They've been posted here before.
   
  Clearly you've never been to a cable manufacturers site, nor do you really seem to care, neither have you looked on a cable box. (often LOTS of information there). You're trying to pursue answers in ways that are simply irrational regarding this topic.
   
  "The detailed performance specifications" are given to you, in how your Headfi colleagues describe cables to you, and how the manufacture details the box and/or (usually really crappy) online description. It's impossible for all the cable manufactures to use words differentiating thousands of cables, your bound to come across similar verbal descriptions. Again, the kind of information you're looking for is also not uniform across any one system or any one headphone. There are synergistic similarities, but none of this can be graphed. You're asking for something totally ridiculous.
   
  Easy way to figure it out: buy cable, demo cable for 15 seconds. If you do not hear a difference,
   
  Either return said cable, or keep it. Either way, you have nothing to lose. There's enough proof in multiple threads to at least warrant an effort on your part at this point. You have no excuse. If you don't want a cable, or don't want to try, that is your choice, but please stop looking ridiculous and dis-acknowledging in some completely meaningless post what took other people (a lot of people) _a lot _of work to conclude about cables.
   
  http://www.head-fi.org/forum/thread/554008/don-t-get-why-audiophile-usb-cable-would-improve-sound-quality/375#post_7525902
  http://www.head-fi.org/forum/thread/555612/cable-discussion-continued-split-from-usb-cable-thread/105#post_7514713
   
   
SUBMIT


----------



## Hennyo

Ok: this thread summarized:
   
  *Decent shiny information all over thread:
   
  absolutely useless junk posts with odd explanations and bitter bystanders wanting to post a word in edgeways*
   
  There: all done. 
	

	
	
		
		

		
		
	


	



  Quote: 





justanut said:


> Maybe I should frame it differently then... for the benefit on Hennyo who would fit in with the term "fanatic" if any would.
> 
> I don't hear a difference using USB cables of different "quality". The believers will say its because I don't BELIEVE in them causing a difference... reverse-placebo? Just like how the non-believers say you hear a difference because of placebo.
> 
> ...


----------



## uelover

Quote: 





justanut said:


> Maybe I should frame it differently then... for the benefit on Hennyo who would fit in with the term "fanatic" if any would.
> 
> I don't hear a difference using USB cables of different "quality". *The believers will say its because I don't BELIEVE in them causing a difference... reverse-placebo*? Just like how the non-believers say you hear a difference because of placebo.


 

  
  Lol. Don't put words into people's mouth for the sake of argument.
   
  The difference *my* USB cable made on my speaker rig is very clear. The listener will be able to pick up the improvement easily and there is no need for me to perform any psychic on him to trick him into 'hearing' any difference.
   
  I am not a believer in USB cables. I am an empiricist.
   
  Seems more like those arguing against the effect of USB cables are the ones who are theorists who cares all about what is written on the sheets and not what is going on in the reality.
   
   
  Like Currawong, I will believe that with certain DACs/cables, the effect is more pronounced.
   
  Also, I am not on the argument that all expensive USB cables will make an improvement. There are probably many snake oil cables out there.
   
  Therefore, if you have tried any so-called 'good' USB cable and did not hear any difference, please post the brand/series of that cable together with the rig you have used for audition (together with photo snap-shots to prove that you have actually heard it yourself). This will allow for a more faithful and objective investigation.


----------



## DaBomb77766

Hennyo, you seem to misunderstand the kind of evidence us cable skeptics want.  We're not looking for anecdotal evidence, which is the only kind of evidence you can show.  Anecdotal evidence, scientifically, is as good as no evidence at all.
   
  The information given on a cable's box is all anecdotal as well.  None of it are real technical measurements that matter.  Maybe if they gave a chart that shows how this cable has a better jitter rating than the competition, or a frequency graph compared to a generic USB cable or something, that would be evidence.  But anecdotal "evidence" is simply not real evidence.  It is nothing but a religious argument at that point, and I still feel that by the way you talk, one could easily substitute "cables" with "jesus" and "god" and you pretty much have a religious argument.
   
  Now, I could try out the cables myself, but honestly, it costs money and I won't always get every last penny of that money back if I don't like what I paid for.  I mean, Locus Design's flagship cable would cost around $700 just to "test" with their dumb return policy in place.


----------



## Hennyo

Quote: 





uelover said:


> Lol. Don't put words into people's mouth for the sake of argument.
> 
> The difference *my* USB cable made on my speaker rig is very clear. The listener will be able to pick up the improvement easily and there is no need for me to perform any psychic on him to trick him into 'hearing' any difference.
> 
> ...


 

 This is a very reasonable post. I feel the same way.

  
  Quote: 





dabomb77766 said:


> Hennyo, you seem to misunderstand the kind of evidence us cable skeptics want.  We're not looking for anecdotal evidence, which is the only kind of evidence you can show.  Anecdotal evidence, scientifically, is as good as no evidence at all.
> 
> The information given on a cable's box is all anecdotal as well.  None of it are real technical measurements that matter.  Maybe if they gave a chart that shows how this cable has a better jitter rating than the competition, or a frequency graph compared to a generic USB cable or something, that would be evidence.  But anecdotal "evidence" is simply not real evidence.  It is nothing but a religious argument at that point, and I still feel that by the way you talk, one could easily substitute "cables" with "jesus" and "god" and you pretty much have a religious argument.
> 
> Now, I could try out the cables myself, but honestly, it costs money and I won't always get every last penny of that money back if I don't like what I paid for.  I mean, Locus Design's flagship cable would cost around $700 just to "test" with their dumb return policy in place.


 
   
  One could argue Anecdotal vs Theory deadlock about pretty much any topic in life. You get nowhere if you're too hardcore with it. Do not twist the meaning of my posts and others.
  The plethora of posts is daunting. The scientific and Theory I see is this: Everyone who's tried it, loves it. Everyone who has not, refuses to acknowledge it. Kinda silly ehh? This whole arguement from each side is paradoxical, and is an endless circle pointing fingers if you approach the topic that way. Pretty words don't solve a disagreement like this, you just have to try it and report what you find. 
   
  The bottom line remains: Those who've tried it: Nigh unanimous,
                                           Those who have not: sadly bitter and demand resolve which unfortunately isn't there.
   
  This is one of those things you just get a feel for. You already know what I mean if you've driven different cars, or tried different headphones, or different speakers, or different girlfriends, You just get a feel for what you like/what variation sounds best. We can make generalizations across avg audience's, but It's simple really. Enjoy or choose not to enjoy, like _anything_ else.


----------



## DaBomb77766

Quote: 





hennyo said:


> One could argue Anecdotal vs Theory deadlock about pretty much any topic in life. You get nowhere if you're too hardcore with it. Do not twist the meaning of my posts and others.
> The plethora of posts is daunting. The scientific and Theory I see is this: Everyone who's tried it, loves it. Everyone who has not, refuses to acknowledge it. Kinda silly ehh? This whole arguement from each side is paradoxical, and is an endless circle pointing fingers if you approach the topic that way. Pretty words don't solve a disagreement like this, you just have to try it and report what you find.
> 
> The bottom line remains: Those who've tried it: Nigh unanimous,
> ...


 


  You seem to be distorting the truth too, I'm afraid.  There are many people in this thread who have tried USB cables, and they said they can find no difference.
   
  The thing is, scientific evidence isn't a "theory."  Evidence is just that: hard data derived from scientific experiments.  Anecdotal evidence has not, and never will, count as "evidence" for scientists.  I simply like the idea of having evidence for everything.  Some things may not be explainable by science - but I tend to disregard these things until real evidence shows up.  I don't believe in a God because there is no provable scientific evidence for His existence.
   
  On the other hand, there is very solid evidence that different headphones sound different.  Same goes for different DACs and amps, there are various tests and measurements out there that show a definite audible difference for them.  On the other hand, there is yet to be a single shred of such evidence for USB cables - the only evidence there is is anecdotal, and I simply cannot accept that.
   
  I will try out so-called "audiophile" USB cables some day, when I have the money to do so - but until then, I'd much rather spend my money on things I know to make a difference, like new headphones or a new amp.


----------



## drez

Quote: 





hennyo said:


> "The detailed performance specifications" are given to you, in how your Headfi colleagues describe cables to you, and how the manufacture details the box and/or (usually really crappy) online description. It's impossible for all the cable manufactures to use words differentiating thousands of cables, your bound to come across similar verbal descriptions. Again, the kind of information you're looking for is also not uniform across any one system or any one headphone. There are synergistic similarities, but none of this can be graphed. You're asking for something totally ridiculous.


 

  LOL pipe down.  Please provide links or quotes to these specs for all of our benefit.  It is perfectly reasonable for us to expect cable manufacturers to publish data for USB cables FURTHER than a mere description of the construction and some vague and misleading talk bout dielectric capacitance, conductor cross section etc.  Regardless any self respecting audio USB cable is designed to reduce jitter, and this can be measured: http://en.wikipedia.org/wiki/Jitter.  Yes there is plenty of useless information on cable boxes, I agree.
   
  The only scope for "synergistic similarities" as you so succinctly refer to is highly tenuous in digital cables, and likely the result of poor logic and an absence of technical understanding or methodological rigor in study of the given technologies.  I have read several "white papers" and to be honest most of them are not up to academic or profession standards.  Some USB cable seem to "talk the talk" in terms of expressing an aim to reduce jitter, but then they usually don't back this up with meaningful data, especially comparing across their own product line.  This makes comparison of performance very difficult until someone applies a strandardised testing methodology that produces empirically comparable data.
   
  What is untenable is to expect one person to buy EVERY single USB cable on the market and test it with EVERY singly usb interface by ear withing a single given lifetime, while holding a job and raising a family and maintaining sanity.  Compared to this some oscilloscope measurements of jitter looks dead easy for someone like Tyll to do.
   
  I am willing to try a USB cable, but if it doesn't work, I am out of pocket by a MINIMUM of $80 unless I can source one of these cables locally.  Tell you what I will try one if I can find a decently designed cable sold locally (chances of this seem slim.)


----------



## svyr

drez said:


> LOL pipe down.  Please provide links or quotes to these specs for all of our benefit.  It is perfectly reasonable for us to expect cable manufacturers to publish data for USB cables FURTHER than a mere description of the construction and some vague and misleading talk bout dielectric capacitance, conductor cross section etc.  Regardless any self respecting audio USB cable is designed to reduce jitter, and this can be measured: http://en.wikipedia.org/wiki/Jitter.  Yes there is plenty of useless information on cable boxes, I agree.
> 
> The only scope for "synergistic similarities" as you so succinctly refer to is highly tenuous in digital cables, and likely the result of poor logic and an absence of technical understanding or methodological rigor in study of the given technologies.  I have read several "white papers" and to be honest most of them are not up to academic or profession standards.  Some USB cable seem to "talk the talk" in terms of expressing an aim to reduce jitter, but then they usually don't back this up with meaningful data, especially comparing across their own product line.  This makes comparison of performance very difficult until someone applies a strandardised testing methodology that produces empirically comparable data.
> 
> ...




http://www.wickeddigital.com.au/index.php?option=com_virtuemart&page=shop.browse&category_id=80&Itemid=53

is that what you were looking for?

 $6,799.00 Locus Design Cynosure USB Cable (6m) lololololol


----------



## MrProggie

Quote:


svyr said:


> Quote:
> 
> 
> 
> ...


   
  They're cryogenically treated...
   
  So I guess they're fantastic, especially in the mid range which is gorgeous according to a reviewer.


----------



## pro555

What is the point to get expensive USB cable when the USB connecters on your computer, the cable between the mother board and the connecter, the USB circuit in your mother board are just made of bare copper? Can Hyundai run faster than Ferrari with best tires? People who make sliver USB cables should also make silver mother board, CPU and USB controller chip, and they all should be "Hi-Fi" treated.


----------



## milosz

I've done blind A/B testing of USB cables. I did the listening myself, and also used a sample of other listeners which included some professional musicians and two "golden ear" guys who claimed for sure they would be able to hear the difference between a 1 meter generic USB cable and a "good" USB cable. They brought their own favorite cables and one brought a cable he thought sounded bad.
   
  None of my listeners was able to tell which cable was in use with reliability higher than 50%, which is to say, none of them could hear any audible differences.
   
  Try it yourself.  Must be done BLIND, however. You can't know which cable is in use.  If you do, the test isn't valid.


----------



## DaBomb77766

milosz, you should relocate that post to the post in the sound science board.  You're not allowed to talk about the results of blind tests here.


----------



## svyr

dabomb77766 said:


> milosz, you should relocate that post to the post in the sound science board.  You're not allowed to talk about the results of blind tests here.




technically, he can't talk about DBT, not BT  see wiki what the difference is. (pretty sure D= if he wrapped the cables in tape and neither he nor the people switching them knew)


----------



## DaBomb77766

Quote: 





svyr said:


> Quote:
> 
> 
> 
> ...


 


  I know that there's a difference...but do they really distinguish between the two here?  I guess we'll leave that for the mods to decide.


----------



## vandaven

No need for a double blind test. 
   
  Recently, I invested in a usb audio interface that is (among other things) built for audio measurements, and also tested this unit with 2 different usb cables. Signal flow for the measurements is Mac Pro -> USB -> DAC -> internal analog connection -> ADC -> USB -> Mac Pro. The resulting impulse response is a deconvolution from a 2 second sine sweep from 1 Hz to Nyquist, measured at 192 kHz 24 bit. 
   
  Unfortunately, I can't upload images at the moment, so you'll have to use the links I have provided:
   
These two cables were tested.
   
Impulse response cable A.
   
Impulse response cable B. 
   
  Have fun.


----------



## Willakan

Can't say I'm even slightly surprised.


----------



## vandaven

Quote: 





willakan said:


> Can't say I'm even slightly surprised.


 

 I am quite surprised by the performance of the audio interface, please mind this is DA-AD (analog out to analog in). I may need to add that the deconvolution is normalized.


----------



## DaBomb77766

Quote: 





vandaven said:


> I am quite surprised by the performance of the audio interface, please mind this is DA-AD (analog out to analog in). I may need to add that the deconvolution is normalized.


 


  Wow, that's actually been converted to analog and back?  That's quite impressive.  Have you done any other tests to post up yet?
   
  Also, maybe you should actually review that piece of equipment if it's really that good.


----------



## Prog Rock Man

Hennyo, why do you feel the need to repeatedly tell us that USB cables make a difference to sound quality? We know that they do, the question is why.
   
  Currawong, I have a reasonable idea how a DAC works. I welcome more measurements on USB cables and if it shown different cables react differently to different DACs we will learn more on the subject.
   
  Vandaven, I take it your measurements show that the different USBs performed exactly the same.


----------



## vandaven

Quote: 





prog rock man said:


> Vandaven, I take it your measurements show that the different USBs performed exactly the same.


 

 Yep. They are. And this is the third USB audio device that I measured. I wonder what esoteric DAC designs may exist, because on all of the ones I tested, it doesn't make a difference. And yes, the Audioquest Cinnamon I used definitely shows less resistance than the stock USB, but in "my" digital world, this difference seems to be insignificant. 
   
  And again, I might want to add that IF you hear a difference between USB cables this difference can be measured. It's a simple, controlled system and not voodoo.
   
  When doing their own measurements, people should mind that USB audio (in general, at least on the Mac) is a tricky beast unless you work with ASIO drivers or on Pro Tools 9. Sometimes (buffer) latency varies extremely. What is important is to make enough measurements of both cables to achieve a base value and thus validity in regards to a possible deviation in sound quality.


----------



## Prog Rock Man

Quote: 





vandaven said:


> Yep. They are. And this is the third USB audio device that I measured. I wonder what esoteric DAC designs may exist, because on all of the ones I tested, it doesn't make a difference. And yes, the Audioquest Cinnamon I used definitely shows less resistance than the stock USB, but in "my" digital world, this difference seems to be insignificant.
> 
> *And again, I might want to add that IF you hear a difference between USB cables this difference can be measured. It's a simple, controlled system and not voodoo.*
> 
> When doing their own measurements, people should mind that USB audio (in general, at least on the Mac) is a tricky beast unless you work with ASIO drivers or on Pro Tools 9. Sometimes (buffer) latency varies extremely. What is important is to make enough measurements of both cables to achieve a base value and thus validity in regards to a possible deviation in sound quality.


 

 But, if the difference in sound quality is down to hype, placebo and other reasons within the listener, not the cable, there will be no measureable difference.


----------



## kr0gg

Quote: 





vandaven said:


> No need for a double blind test.
> 
> Recently, I invested in a usb audio interface that is (among other things) built for audio measurements, and also tested this unit with 2 different usb cables. Signal flow for the measurements is Mac Pro -> USB -> DAC -> internal analog connection -> ADC -> USB -> Mac Pro. The resulting impulse response is a deconvolution from a 2 second sine sweep from 1 Hz to Nyquist, measured at 192 kHz 24 bit.
> 
> ...


 

 your results actually differ.
  i guess that proves that USB cables are not the same?


----------



## svyr

kr0gg said:


> your results actually differ.
> i guess that proves that USB cables are not the same?




at the bottom of the largest spike they slightly do. maybe 10mv or something. Can't see anything else.


----------



## jackmccabe

Quote: 





kr0gg said:


> your results actually differ.
> i guess that proves that USB cables are not the same?


 
  Of course they are different, they are probably made out of different materials.
  They just aren't audibly different when in use.


----------



## svyr

maybe some rightmark tests http://audio.rightmark.org/index_new.shtml  ?


----------



## jackmccabe

Quote: 





svyr said:


> maybe some rightmark tests http://audio.rightmark.org/index_new.shtml
> 
> 
> 
> ...


 

 All they will measure is the noise floor and distortion of the dac.


----------



## svyr

jackmccabe said:


> All they will measure is the noise floor and distortion of the dac.




FR chart and +-X db over the range, crosstalk, THD+N and IMD. Surely USB cables sounding clearer/different will be reflected on those, since proponents claim they're easily audible


----------



## Prog Rock Man

Quote: 





svyr said:


> Quote:
> 
> 
> 
> ...


 



 Is it not more like 1mV? Even then it is at the same time. How audible is that going to be (he said banging on like a stuck record, but audibility is the elephant in the room many want to ignore 
	

	
	
		
		

		
		
	


	




)


----------



## vandaven

Quote: 





kr0gg said:


> your results actually differ.
> i guess that proves that USB cables are not the same?


 

 The difference is extremely minimal. Any of these "micro" differences is probably induced by the tolerance of the analog circuitry. Please mind the signal is DA-AD and passes through the analog domain. There is a lot of (pro) gear out there which won't give you such a clear "matching" result on 2 measurements, even when taken under identical circumstances.


----------



## limpidglitch

Quote: 





vandaven said:


> (…) taken under identical circumstances.


 

  
  Sounds like a good idea 
	

	
	
		
		

		
		
	


	



  A control so to speak, to check the cosistency of the test.
  Now if intraspecific differences and interspecific differences are close enough, you'll have a definitive negative.


----------



## jackmccabe

Quote: 





svyr said:


> FR chart and +-X db over the range, crosstalk, THD+N and IMD. Surely USB cables sounding clearer/different will be reflected on those, since proponents claim they're easily audible


 


  True I just forgot people actually believe there will be a measurable difference.


----------



## kr0gg

you know, that is really funny.
  at first (during a LOT of forum pages) you decline that there is ANY difference at all, and when finally you yourself discover one, you refuse to see it 
  i wouldn't call that a scientific approach (as you try to make us belive it is). i would call that a "cable-nihilism"


----------



## Hennyo

The difference is unmistakable, sound changing, and is radically different. Second only to using better headphones or a much higher end Dac/amp.
   
  Krogg is completely right. You don't give it a chance. Even when there's a glimmer of proof that is along lines you are willing to accept, you _reject_ it. Complete cable-nihilism.
   
  All of you 'denyers' have said controversial, nonsensical, paradoxical things. Thier 'Anecdote vs Theory' battle or whatever it is they are trying to communicate is way out of hand. Not to mention certainly circular and pointless.
   
  The bottom line is there are differences and they are not minimal, as every person who has tried instantaneously comes to realize. (Magic?) Furthermore, people are describing the differences in great detail their sound has made. Does that sound like bs to you?


----------



## vandaven

Quote: 





kr0gg said:


> you know, that is really funny.
> at first (during a LOT of forum pages) you decline that there is ANY difference at all, and when finally you yourself discover one, you refuse to see it
> i wouldn't call that a scientific approach (as you try to make us belive it is). i would call that a "cable-nihilism"


 

 erm, do you really know how an audible difference would look like as an impulse response?


----------



## MrProggie

Quote: 





hennyo said:


> The difference is unmistakable, sound changing, and is radically different. Second only to using better headphones or a much higher end Dac/amp.
> 
> Krogg is completely right. You don't give it a chance. Even when there's a glimmer of proof that is along lines you are willing to accept, you _reject_ it. Complete cable-nihilism.
> 
> ...


 

 Error correction circuits in the DAC will fix small errors like that. You will not hear the difference.


----------



## Hennyo

Quote: 





mrproggie said:


> Error correction circuits in the DAC will fix small errors like that. You will not hear the difference.


 

  
  Every cable would have a different graph like that. That's getting utterly nitty gritty moving towards exhausting uselessness. You don't want to try it, then DON'T. But get off those who have, especially when the masses say they enjoy the difference their cable clearly make in their system. Jeebus
  This is a circular argument which leads nowhere. Let the people decide. Have you tried it? No? Then your opinion is worth *less.* (If anything at all)
   
  Just because you can't comprehend something at this time does not mean it doesn't exist at all.


----------



## jackmccabe

Quote: 





hennyo said:


> Every cable would have a different graph like that. That's getting utterly nitty gritty moving towards exhausting uselessness. You don't want to try it, then DON'T. But get off those who have, especially when the masses say they enjoy the difference their cable clearly make in their system. Jeebus
> This is a circular argument which leads nowhere. Let the people decide. Have you tried it? No? Then your opinion is *worthless.*


 

 This is only a circular argument because cable believers make it so, multiple pieces of evidence have been provided that show there is no difference...
  but do you accept that , no you are to wrapped up in your fantasy reality that you just go into complete denial and attack people.
  If you can "hear a difference, it is because your mind is playing tricks with you, whether you are happy with imaginary differences or not is up to you.
   
  I would just like to remind you your opinion is not valid and is completely worthless, you are massively bias towards your own self-interest, test and measurements on the other hand are not.


----------



## Omega17TheTrue

Has someone here made a true blind test (with a second people changing cable randomly) against ultra cheap cable and ultra high-end ones ?

If you can't hear any differences it is completely useless.


----------



## Prog Rock Man

Quote: 





hennyo said:


> Every cable would have a different graph like that. That's getting utterly nitty gritty moving towards exhausting uselessness. You don't want to try it, then DON'T. But get off those who have, especially when the masses say they enjoy the difference their cable clearly make in their system. Jeebus
> This is a circular argument which leads nowhere. Let the people decide. Have you tried it? No? Then your opinion is worth *less.* (If anything at all)
> 
> Just because you can't comprehend something at this time does not mean it doesn't exist at all.


 



 Are you going to contribute anything at all to answering the question as to why USB cables make a difference. Or are you just going to further contribute to the circular argument that leads nowhere and constantly tell us what we already know, that they do make a difference?
   
*WE KNOW THAT USB CABLES MAKE A DIFFERENCE TO SOME PEOPLE SOME OF THE TIME. CAN YOU PLEASE CONTRIBUTE EVIDENCE TO ANSWER THE QUESTION WHY IS THAT?*


----------



## Hennyo

Quote: 





jackmccabe said:


> This is only a circular argument because cable believers make it so, multiple pieces of evidence have been provided that show there is no difference...
> but do you accept that , no you are to wrapped up in your fantasy reality that you just go into complete denial and attack people.
> If you can "hear a difference, it is because your mind is playing tricks with you, whether you are happy with imaginary differences or not is up to you.
> 
> I would just like to remind you your opinion is not valid and is completely worthless, you are massively bias towards your own self-interest, test and measurements on the other hand are not.


 

 This guy makes my day everytime.
  /putting words into other peoples mouths, as usual.


----------



## jackmccabe

Edited


----------



## Hennyo

Quote: 





jackmccabe said:


> You are not allowed to discuss them here, I suggest you go to the sound science forum.


 

 Way to troll out a thread. Hopeless.
   
  Congrats, you've successfully decimated a perfectly fine thread, almost single handedly. Plague-like indeed. (Follow back through whole thread).


----------



## jackmccabe

Quote: 





hennyo said:


> Way to troll out a thread. Hopeless.
> 
> Congrats, you've successfully decimated a perfectly fine thread, almost single handedly. Plague-like indeed. (Follow back through whole thread).


 

 ???
  They are the rules, I was just informing a member so he does not get not into trouble.
  This thread has no evidence what so ever that points to there being differences.
  Just because cables are different that does not mean there are any audible differences.


----------



## vandaven

Some last measurements, for the community to decide:
   
difference01
   
difference02
   
  This will be my last measurement here. The cable crowd is too ignorant. I want to emphasize on the fact that I own several "audiophile" USB cables that I bought for my measurements, and I keep them just out of vanity 
	

	
	
		
		

		
			





. Can't hear any difference between them. Not Audioquest, Oyaide Neo or Wireworld Starlight.
   
  Apart from that, after providing so much evidence (that apparently is NOT understood anyway), I would like to see some evidence for the difference that some can hear.
   
  Who beliefs that the cable does the same to the signal quality than a well designed DAC, headphone amplifier or pair of headphones may believe whatever he wants to believe. 
  It's a free world after all. 
   
  Accepting the fact that a signal might look "a bit" different in the analog domain seems to be very hard.


----------



## TheGame21x

That's because it probably won't.

 USB cables transmit entirely digital signals and with digital signals, it either works or it doesn't, to put it simply. That's also why paying more than $5 or so for an HDMI cable (obviously scaling up or down accordingly depending on the length you want) is stupid.


----------



## vandaven

Quote: 





thegame21x said:


> That's because it probably won't.
> 
> USB cables transmit entirely digital signals and with digital signals, it either works or it doesn't, to put it simply. That's also why paying more than $5 or so for an HDMI cable (obviously scaling up or down accordingly depending on the length you want) is stupid.


 

 That is what some of us are trying to prove for weeks...


----------



## uelover

Quote: 





vandaven said:


> No need for a double blind test.
> 
> Recently, I invested in a usb audio interface that is (among other things) built for audio measurements, and also tested this unit with 2 different usb cables. Signal flow for the measurements is Mac Pro -> USB -> DAC -> internal analog connection -> ADC -> USB -> Mac Pro. The resulting impulse response is a deconvolution from a 2 second sine sweep from 1 Hz to Nyquist, measured at 192 kHz 24 bit.
> 
> ...


 


 Hey vandaven, nice test there.
   
  Wonder if you could run a test for high frequencies too, eg 8khz, 10khz?
   
  Another way would be to record the entire track played on one cable vs another cable, saved the audio file and post it here and labelled them as file A and file B for us to hear.
   
  I have been wanting to perform such test myself but am limited to the equipment I currently have.


----------



## vandaven

Quote: 





uelover said:


> Hey vandaven, nice test there.
> 
> Wonder if you could run a test for high frequencies too, eg 8khz, 10khz?
> 
> ...


 

 Hi Uelover, I am just trying to prove my point. This is the deconvolution of a sine sweep from 1 Hz to Nyquist frequency. Nyquist fq is defined by fs/2. Thus, a sweep from 1 Hz to 96 kHz, as the sample fq was 192 kHz. In this section, I am afraid blind tests are not allowed. I could post something like that in the parallel thread on the sound science quarter of this site. Nonetheless, a whole track wouldn't be allowed, I guess I'll take the iTunes preview limitations of 30 seconds for that.


----------



## justanut

My bad if you misunderstood me. I'm not trying to put words into anyone's mouth, but just thinking out loud on the possible retort. I've mentioned it before too that I'm very interested to know what is the variable causing the marked differences in audio quality when different USB cables are used in some people's setups. Although personally I haven't had a chance to experience it. Perhaps one day I shall really have to go over to your place and have a listen 
   
  Like I mentioned, I'm wondering if differences are caused by the DAC (that has certain requirements that the audiophile USB cables meet while the normal USB cables don't). Is it something that can be replicated on normal USB cables once we know the requirement?
   
  Personally I do own the Cardas Blue. Its relatively cheap and well built, which is why I bought it. I THINK I hear a difference between it and my normal computer USB cable... after listening really long and hard... but my wife doesn't. But then again she wasn't able to tell any audio differences between my Mundorf gold LOD and the Copper LOD I had either. Although she could tell the difference between my Beyer T50p and the Ultrasone Ed8...
   
  My uncle swears by his Axis USB cable, which I've compared with using my Cardas... again I THINK there's a difference but I can't be sure. Although my uncle next to me would excitedly point out the qualities of the Axis when in use... the better defined bass, the increased soundstage etc... All of which isn't logically possible to me.
   
  I've also failed to hear any difference between the $15 iPod USB LOD and the $100+ one sold for the CLAS... which prompted me to go back and compare my USB cables actually, and started me on this quest.
   
  I've read the descriptions of a few more popular USB cables, including the Cynosure. Alot of emphasis is made on the material used, the damping, the shielding, the isolation of the Data line from the VDC line... I suspect that perhaps the isolation part makes some sense... but i'm not EEE grad.
   
  What exactly makes audiophile USB cables different from normal computer USB cables? I'll be upfront and say that I don't believe in difference in material making a difference over such a short distance. How they shield and isolate the cables might cause some difference though (I've heard jitter mentioned a couple of times in this discussion for example). Is that the only difference that causes the huge disparity in price?
   
  Is it too much to know what I'm paying for? I appreciate people like Van who are trying to provide data to aid this enquiry. However its pointless to be shouting over and over that there is a difference when I've tried to hear a difference and failed to. Maybe 18 year olds have got better ears? Oh and Hennyo (I've to highlight you since you really do get on my nerves), don't assume and put words in other's mouth too. I for one HAVE compared relatively well built and reasonably priced USB cables against pricier but not crazy pricier USB cables. 
   
  Btw, can those who hear a difference articulate the differences? Not a trick question, but I really want to now what to look out for when I do my own comparison.
   
  Sorry for the long post


----------



## justanut

Btw, since we're on this... My songs are stored on an external hard drive that is connected to my Macbook Pro via Firewire... I was just thinking if there's anyone who actually uses an "Audiophile" USB cable to connect their external hard drives to their computers before connecting another Audiophile USB cable from the computer to the DAC?
   
  Is there any manufacturer that sells Audiophile SATA connectors or Firewire cables?


----------



## Mambosenior

Quote: 





			
				justanut said:
			
		

> *justanut*





> Is there any manufacturer that sells Audiophile SATA connectors or Firewire cables?


 
  Just give me a couple of days. I'll build you what you want.
   
  Any color preferences?


----------



## uelover

Hmm describing the improvement in sound about a certain area and then asking the listener to listen for it might introduce the potential effect of placebo upon a listener =)
   
  Up till the point of the USB module on your motherboard, everything has digital error correction so there is no need for 'good' or 'snake-oil' cables used in between.


----------



## uelover

Quote: 





mambosenior said:


> Just give me a couple of days. I'll build you what you want.
> 
> Any color preferences?


 


  Diamond cladded ones look good. I can wear them around my neck. Said to improve SQ through extensive EM rejection =)


----------



## DaBomb77766

The day that someone buys and says they can tell the difference between an "audiophile" SATA cable and a standard one is the day I leave the audiophile community.


----------



## tmars78

Quote: 





dabomb77766 said:


> The day that someone buys and says they can tell the difference between an "audiophile" SATA cable and a standard one is the day I leave the audiophile community.


 
   
   
  Bye...I hardly even knew you. 
	

	
	
		
		

		
			




   
http://www.malcolmsteward.co.uk/?p=2534
   
  And here, the same guy says it again:
   
http://www.malcolmsteward.co.uk/?p=2495#comments
   
   
   
  ETA: I think Mr. Steward is an idiot. 
   
  .


----------



## svyr

vandaven said:


> The difference is extremely minimal. Any of these "micro" differences is probably induced by the tolerance of the analog circuitry. Please mind the signal is DA-AD and passes through the analog domain. There is a lot of (pro) gear out there which won't give you such a clear "matching" result on 2 measurements, even when taken under identical circumstances.




m, looks most likely to be a conversion/measurement artifact. Anything audible would have to be a lot larger differences anyway, unlike what 

>at first (during a LOT of forum pages) you decline that there is ANY difference at all, and when finally you yourself discover one, you refuse to see it  i wouldn't call that a scientific approach (as you try to make us belive it is). i would call that a "cable-nihilism"


says


----------



## DemonicLemming

Hah, I didn't read the whole thing, but I bet that got some "interesting" responses from the arf-commers.
   
  Course, if LaRue came out with an optics mount that promised fewer FTEs, it would be the new trend of the month over there.  Every community has its manias.
  
  Quote: 





tmars78 said:


> Bye...I hardly even knew you.
> 
> 
> 
> ...


----------



## n3rdling

Quote: 





hennyo said:


> This guy makes my day everytime.
> /putting words into other peoples mouths, as usual.


 

 You're the person that keeps assuming that everybody who has posted saying they don't believe in USB cables has "never tried it themselves".  You've been wrong everytime.


----------



## DaBomb77766

Quote: 





tmars78 said:


> Bye...I hardly even knew you.
> 
> 
> 
> ...


 


  ...okay, I'll admit, that was just an empty threat, I actually had faith in humanity for a moment there.


----------



## justanut

Jena Copper Firewire 800 cables with gold plated plugs? I like my sound to be warmer and detailed 
	

	
	
		
		

		
		
	


	



   
  Its a joke in case no one realised >..<

  
  Quote: 





mambosenior said:


> Just give me a couple of days. I'll build you what you want.
> 
> Any color preferences?


----------



## justanut

All meant to be mildly sarcastic and maybe invoke some food for thought...
   
  Mmm don't DACs come with error correction built into the USB protocol? It can't be that we're paying good money for something that can't even do that? Will better cables do error correction for us or prevent errors? Those high end cables cost more than a netbook which doesn't require such high grade USB cables to effectively transfer my data from one USB end to the other >..<
   
  This is all so confusing and smells...
  
  Quote: 





uelover said:


> Hmm describing the improvement in sound about a certain area and then asking the listener to listen for it might introduce the potential effect of placebo upon a listener =)
> 
> Up till the point of the USB module on your motherboard, everything has digital error correction so there is no need for 'good' or 'snake-oil' cables used in between.


----------



## uelover

Quote: 





justanut said:


> Mmm don't DACs come with error correction built into the USB protocol? It can't be that we're paying good money for something that can't even do that?


 

 I think it has been mentioned many times in this thread that there is no error correction for USB audio because it is different from other USB appliances.
   
  Question in this thread is: Is 'good' USB cable capable of reducing the errors and whether that will lead to an *audible* increase in SQ.


----------



## drez

problem appears the same conundrum as believing in ghosts and UFO's.  Many people say they exist but nobody can prove it.
   
  If a magician fools you into thinking his tricks are real, they probably are to those who witness this trick, or shared the common experience of being tricked.  But this is not my creed anyway.
   
  I would not mind paying for a cable if it is *proven* to reduce distortion beyond mere speculation and marketing claims.  Problem is currently I am reliant upon the questionable opinion of others in choosing a USB cable.
   
  IT seems to be the case that those who think USB cables work cant explain it, and those that believe they can explain how they might work don't seem to think they would, yet some still concede it might be theoretically possible in certain specific cases [to reduce jitter].
   
  To me only a few cables which have some semblance of logic, but even then they are *appear* not to be up to my ideal level of design rigor, both theoretical and methodological, at leas from they publish on the web.
   
  Say for example, impedance matching in digital coax is now a given, yet only a handful of cable builders apply this approach to USB and then only on expensive models, and even then don't explain how and why this would be effective to any respectable degree, thus why academics [rightly] mock them.
   
  Maybe DIY is the only way to find a decent cable?
   
  Am i repeating myself also


----------



## svyr

>It can't be that we're paying good money for something that can't even do that? 

and yet you are. 


>Will better cables do error correction for us or prevent errors? 

no, very unlikely unless your stock cable is not to spec.


>I think it has been mentioned many times in this thread that there is no error correction for USB audio because it is different from other USB appliances.

that's correct. USB audio devices generally use isochronous async, sync or adaptive endpoints. While they can detect errors by calculating checksums, NONE of those have error correction or retransmission on error. The decision was originally motivated by usb audio needing guaranteed latency/bandwidth, but for playback it really doesn't matter it seems.(especially for class 2 usb audio devices on USB 2.0 buses and with no other devices sitting on that internal usb hub port) 

'Isochronous pipe: These pipes are intended for isochronous data, for example video or audio streams, with fixed latency/and guaranteed bandwidth, but no guaranteed delivery. Isochronous packets are however not retried in case of failed delivery or NAK of a packet as this might violate the timing constraints.'

http://www.beyondlogic.org/usbnutshell/usb4.shtml (this mirrors the usb spec details but is a bit easier to read)


The only DACs that DO have error correction are the ones transferring the data in bulk mode. Where the data is sent to the custom bus driver/retransmitted on error (that's actually the cypress USB chip and then from there in I2S to the DAC chip (musilol is the only one I know of, but there are probably 1-2 more). 

>Those high end cables cost more than a netbook which doesn't require such high grade USB cables to effectively transfer my data from one USB end to the other >..<

like the bulk transfer mode audio cards mentioned above, USB devices like hard drives also use bulk mode (w error detection and correction) and don't worry about cables unless you're using a not-to-spec coathanger.


----------



## Prog Rock Man

Quote: 





tmars78 said:


> Bye...I hardly even knew you.
> 
> 
> 
> ...


 



 Those links are shocking. It really is very difficult to have a proper evidenced discussion about cables, but to get a death threat??????!!!!
   
  At least here we have had Vandaven's superb contribution showing that any difference between USB cables is minor, so minor it is beyond all reasonable doubt that they make a difference to sound quality. We know beyond all reasonable doubt that cable hype, placebo, buyer justification are very good reasons as to why people hear a difference in USB (and any other) cable.
   
  So with this thread and how the two sides of the deabte have conducted themseleves and the evidence they have brought forwards, I am now even more certain than before that no cable inherantly, by its construction makes a difference in hifi. It is all in the listeners mind.


----------



## svyr

prog rock man said:


> Those links are shocking. It really is very difficult to have a proper evidenced discussion about cables, but to get a death threat??????!!!!




If someone believes you can transfer data in bulk mode with full error detection and retransmission on errors (and/or error recovery mechanisms) and a cable affects sound they kinda.... Well, at least sterilization...


----------



## justanut

Awesome replies svyr! Thanks for the effort taken! Thats what I love about open discussions... I get to learn stuff I'm otherwise too lazy to find out myself haha!
   
  And I totally agree that USB cables are *NOT* the answer to error correction/prevention. So what effect do they have, if any at all? Seems that there have been conclusions drawn by Prog that they do nothing more than the $10 well built USB cable, and I'm really inclined to believe so.
   
  But still, I'm keeping an open-mind for the sake of the other 50% who say otherwise and eagerly await their presentation of scientific proof 
   
_"Does a tree make any noise when it falls when there's no one else (or recording device haha!) in the forest?" _




  
  Quote: 





svyr said:


> >It can't be that we're paying good money for something that can't even do that?
> 
> and yet you are.
> 
> ...


----------



## uelover

Quote: 





prog rock man said:


> *We know beyond all reasonable doubt* that cable hype, placebo, buyer justification are very good reasons as to why people hear a difference in USB (and any other) cable.


 

 Lol. Typical elementary school response.
   
  With one set and one type of experiment, you arrived straight at a conclusion?  Even scientists need many different sets of experiment under different environment to conclude certain things.
   
  This is a good example of what an affirmative bias does to cloud our thinking.
   
   
*Taking a strong assumption* that the test Vandaven has done is the correct and suitable test:
   
  Vandaven claimed of no difference is in line with his test result. This may act as a good control showing that USB cable has no effect on his setup.
   
  However, even under such an assumption, it will also be important to test on systems where claims of difference between USB cables are heard. This has not been performed.
   
   
   
  Unless, as Prog Rock Man wants to believe, Vandaven is the only one that has got technical ears/brain which cannot be fooled and therefore what he heard will always be in-line with what is measured. =)


----------



## justanut

Agree with that uelover! Now its time for those who heard differences in their setups to perform a similar analysis. I'm really interested if there really are differences detectable by instruments of modern science, so that we can zoom in and try and decipher what that variable really is!
   
  But I think they gotta borrow Van's "normal" USB cable to do the test with...


----------



## svyr

justanut said:


> And I totally agree that USB cables are the answer to error correction/prevention. So what effect do they have, if any at all?



re-read what I posted lol... Bulk USB transfer mode audio devices for playback (can't do that for real-time recording/monitoring systems though) are the answer, since any errors are simply retransmitted (if they occur at all), and the cable ceases to matter. (unless you believe platinum sata and usb cables will make your hard drive go faster. In that case I suggest polishing the hard drive plates and sterilization. No wait, I can get one made for you, friend is a jeweler. We'll charge about $20000/m, with the raw material cost of about $500/m  . Please buy one. I really don't want to work a day job anymore and am considering a life of a shameless fraud  ) 

For normal isochronous (sync, async, adaptive transfer mode) USB audio devices, the max you will _possibly_ get is a lower error rate(very improbable considering the measurements we've recently seen and the consequences of dropping 1-2 samples being pretty negligible and the to-spec cable probably being design to not drop (m)any packets at all). No cable even if it's silver with diamond crust on top will ever do error correction for you for isochronous usb transfer mode devices, no matter how much you wish for it


----------



## Prog Rock Man

Quote: 





uelover said:


> Lol. Typical elementary school response.
> 
> With one set and one type of experiment, you arrived straight at a conclusion?  Even scientists need many different sets of experiment under different environment to conclude certain things.
> 
> ...


 



 Not just Vandavens measurements, also the general role and affects of cables in hifi as shown by the difference between sighted, blind and ABX testing and the influence of hype.
   
  So far, any measurement of a cable, whether that is by Vandaven, cable makers themselves or others who have tested them such as Nick_Charles have found very small differences. The cable makers suggest that those differences account for differences in sound quality, but cannot show a proven link to that. Vandaven and Nick_Charles present a strong case that the differences are not audible at all.
   
  The link to audibility is found with sighted testing where people are affected by hype (placebo etc).


----------



## uelover

Quote: 





justanut said:


> But I think they gotta borrow Van's "normal" USB cable to do the test with...


 

 Need his recording equipment as well. Seems like he is using Pro Tools for recording.
   
  Any kind soul from SG who are willing to lend his/her recording equipment please raise up your hand!


----------



## vandaven

Quote: 





uelover said:


> *Taking a strong assumption* that the test Vandaven has done is the correct and suitable test:
> 
> Vandaven claimed of no difference is in line with his test result. This may act as a good control showing that USB cable has no effect on his setup.
> 
> However, even under such an assumption, it will also be important to test on systems where claims of difference between USB cables are heard. This has not been performed.


 

 First off, please, we all know a discussion can get heated from time to time, no need to start being rude. 
   
  The interesting thing I want to mention (and I guess I have mentioned it a long way down the discussion thread) is that me and my brother could both hear a difference between the Audioquest cable and a stock cable when I first got it.
   
  Even now, I get the impression things sound better with it. And that's cool, because I want to live in that bubble of sound. That's the romantic side of my personality. The one that likes shiny equipment and geeky cables (and I still do like them because they look different). 
   
  I joined this site because I wanted to get qualitative information about certain types of headphones and amplifiers, and there's plenty of such info here. These are impressions. And such impressions are important because they make us analog human beings, through our language, we are able to describe more than just a "0" or a "1", we can explain in many words why we prefer certain things.
   
  Many people here insist on the fact that they hear a difference in their USB cables. "Alright, I heard the difference too", I thought to myself. But persisting on an opinion without having any proof or evidence, like many here do (and some of them with an amusing, childlike charm), doesn't work against skeptics, and would never work in any other environment. 
   
  And then I run the tests, I do the measurements, and I can't find any evidence that I can show to people who are probably more skeptical than me. Because, again:
   
  - there might be a difference in manufacturing and cable quality BUT
  - USB audio will not benefit from that
   
  Cheers!


----------



## justanut

Ahhh typo! I meant are NOT the answer... LOL!
  
  Quote: 





svyr said:


> Quote:
> 
> 
> 
> ...


----------



## uelover

Quote: 





vandaven said:


> First off, please, we all know a discussion can get heated from time to time, no need to start being rude.


 

  Hmm my previous post was not meant to be rude to you please don't take it that way.
   
  I mean, we may not know the appropriate test to perform for something that is so elusive.
   
  For instance, is electron a wave or a particle? What is the correct test that we should perform to ascertain its nature? We may observe and conclude that electron is a particle. But then, we may missed out something because it exhibits wavelike nature under no observation. So which claim is valid? Or is there a better and more suitable test that we have yet to discover?
   
  I am not suggesting that USB cables are like electrons but I am accepting the possibility of potential blindspot that we may have missed out.
   
  This post is a sidetrack to the discussion.


----------



## kr0gg

Quote: 





uelover said:


> For instance, is electron a wave or a particle? What is the correct test that we should perform to ascertain its nature? We may observe and conclude that electron is a particle. But then, we may missed out something because it exhibits wavelike nature under no observation. So which claim is valid? Or is there a better and more suitable test that we have yet to discover?


 
   
   
  finally someone asked this question aloud


----------



## DaBomb77766

Quote: 





kr0gg said:


> finally someone asked this question aloud


 

  
  Well, with our current scientific knowledge, both claims are equally valid, and there is no reason to doubt that (not yet).


----------



## kr0gg

the point is that to truly "scientifically" research something's effect you have to fully know it's nature.
  without knowing it completely we can only measure a limited range of characteristics.
  finally, all these tests that were conducted told us actually ONLY possible variations in _those characteristics that we know about_
  and, assuming that those tests were made in appropriate way using ideal instruments, anyway we can only say that _we didn't see any cable effect on electrical characteristics that we know and we can measure_


----------



## DaBomb77766

Quote: 





kr0gg said:


> the point is that to truly "scientifically" research something's effect you have to fully know it's nature.
> without knowing it completely we can only measure a limited range of characteristics.
> finally, all these tests that were conducted told us actually ONLY possible variations in _those characteristics that we know about_
> and, assuming that those tests were made in appropriate way using ideal instruments, anyway we can only say that _we didn't see any cable effect on electrical characteristics that we know and we can measure_


 


  ...so are you suggesting that cable companies are utilizing an electrical phenomenon unknown to modern science?


----------



## uelover

Quote: 





dabomb77766 said:


> ...so are you suggesting that cable companies are utilizing an electrical phenomenon unknown to modern science?


 

 As far as I know by looking back into history, many inventions/discoveries came before science stepped in to try to explain for them. I am not condescending science. But I need to be aware of its limitation.
   
  Anyway, not suggesting something as far-fetched that cable companies are so superior to be adopting techniques unknown to modern science.
   
  Looking at many of the cables line-up, most USB and Digital Coaxial cables' seem to be a mere copycat of their analogue offerings. Not sure even if the cable companies understood why those techniques seem to work well for digital cables.


----------



## svyr

dabomb77766 said:


> ...so are you suggesting that cable companies are utilizing an electrical phenomenon unknown to modern science?




we're already into ghost territory as proposed before lol. When no measurable difference is shown our friends are looking for mystical explanations


----------



## DaBomb77766

Quote: 





uelover said:


> As far as I know by looking back into history, many inventions/discoveries came before science stepped in to try to explain for them. I am not condescending science. But I need to be aware of its limitation.
> 
> Anyway, not suggesting something as far-fetched that cable companies are so superior to be adopting techniques unknown to modern science.
> 
> Looking at many of the cables line-up, most USB and Digital Coaxial cables' seem to be a mere copycat of their analogue offerings. Not sure even if the cable companies understood why those techniques seem to work well for digital cables.


 


  The problem is, attributing the differences cables make to new, unproven science, in order to justify an unproven idea (the idea that these cables are actually making an audible difference) is no different from the "god of the gaps" argument.


----------



## jackmccabe

Quote: 





kr0gg said:


> the point is that to truly "scientifically" research something's effect you have to fully know it's nature.
> without knowing it completely we can only measure a limited range of characteristics.
> finally, all these tests that were conducted told us actually ONLY possible variations in _those characteristics that we know about_
> and, assuming that those tests were made in appropriate way using ideal instruments, anyway we can only say that _we didn't see any cable effect on electrical characteristics that we know and we can measure_


 


  We currently know that an ideal amplifier/ dac produces no distortion, there fore it will output the signal exactly as it was input.
  Of course their are many types of distortion, but these are all fairly easy to measure, unfortunately the one thing we can't measure is placebo effect and bias.
  It is far far more likely that people are being fooled than there is something that cables make a difference to that modern science can't measure, it is just ridiculous to suggest otherwise.
   
  The problem with high-end audio is that much of it is subjective and people are very arrogant and unwilling to accept facts as they 100% believe in their opinion.
  Yes, people continue to argue because they are so stubborn that even when faced with facts, they will reject them because they know they are right.
  I just wonder how people could even bother arguing that there are differences when they haven't performed any sort of controlled listening tests.


----------



## vandaven

The problem is that people are not willing to accept that whatever happens between the audio interface and the computer is a controlled digital system with no "esoteric" possibilities.


----------



## uelover

Quote: 





jackmccabe said:


> It is far far more likely that people are being fooled than there is something that cables make a difference to that modern science can't measure, it is just ridiculous to suggest otherwise.
> 
> The problem with high-end audio is that much of it is subjective and people are very arrogant and unwilling to accept facts as they 100% believe in their opinion.
> Yes, people continue to argue because they are so stubborn that even when faced with facts, they will reject them because they know they are right.


 
   
  Lol. After such a long time, flaming starts again.
   
  Problem with the other half of the camp is that even with one just test result (even when there is a lack of treatment group and the entire test setup and procedure is unknown) the phenomenon of affirmative bias sets in.
   
  I could not even confirm the test on my end due to the lack of equipment and Vandaven had just ignored my PM to him questioning the tools he used for the test.
   
  Then, people sitting on the side just jump in and started flaming again.
   
  In any case, seems like there is no one here genuinely interested in performing a well-controlled experiment. Wasted my time here these past two days getting back into this thread hoping to meet some good and tech-savvy Samaritans.


----------



## DaBomb77766

Quote: 





uelover said:


> Lol. After such a long time, flaming starts again.
> 
> Problem with the other half of the camp is that even with one just test result (even when there is a lack of treatment group and the entire test setup and procedure is unknown) the phenomenon of affirmative bias sets in.
> 
> ...


 


  Rest assured his test equipment is adequate for the job.  His test was well-controlled...what makes you think otherwise?  If anything, if it wasn't well-controlled that's when differences would show up.  He used a good DAC-ADC and it showed a minimal difference.  Unless he fudged the data there's not much else that can be done...others are free to do the same, but it will have the same effect.


----------



## vandaven

Quote: 





> Originally Posted by *uelover* /img/forum/go_quote.gif
> Then, people sitting on the side just jump in and started flaming again.
> 
> In any case, seems like there is no one here genuinely interested in performing a well-controlled experiment. Wasted my time here these past two days getting back into this thread hoping to meet some good and tech-savvy Samaritans.


 

 Uelover, 
   
  in each and every test I've shown on this thread and the parallel thread here http://www.head-fi.org/forum/thread/555612/cable-discussion-continued-split-from-usb-cable-thread/105#post_7514713 the equipment was mentioned.
   
  I kindly forwarded you the test results as WAV files and you took a look at them.
   
  I am sorry that I also got other stuff to do than to repeat myself all day long.


----------



## Willakan

Wait a sec, nothing needs proving. We're not breaking new ground here - the fact these cables do absolutely nothing to the sound (nothing as in nothing significantly measurable that can be shown to vary consistently between cable designs or types - something that is approaching the boundary of measuring equipment resolution, let alone the hearing resolution of the human ear) if they are competently designed has already been established scientifically - vandaven was just presenting yet more evidence in an effort to persuade some more people with some visual examples.
   
  Cables, especially digital, are not some mystical uncharted science. The work in defining the (low) quality of cable required to transmit any form of USB/HDMI/other digital standard to a standard that is to all intents and purposes perfection was laid down by the people who defined the standards. Funnily enough, they don't specify "Litz cable geometry to improve transfer" in those documents. 
   
  If we're going to go the whole "not enough evidence route," the theory has been laid down that says "Cables will not make a difference to the end-user." Testing was then done, so this became established scientific doctrine. For this to change, some evidence must be presented that makes that statement seem incorrect. Evidence that is heavily biased is below contempt. Of course, if evidence could be presented demonstrating the cables were distinguishable under blind testing, that would be different - but that has never been done - wonder why?
   
  The only people left making "advances" in the field are the cable manufactures, who busily sell various products that do nothing for extortionate prices, based on "science" that is presented in a hugely misleading fashion - eg making out that heavy attentuation of frequencies far outside the human hearing range is an audible issue (gonna miss those 1khz tones). This kind of science makes little sense when applied to analogue audio cables - when you move to the digital domain even audiophiles that believe in analogue cables making differences become sceptical, and with good reason.


----------



## kr0gg

Quote: 





dabomb77766 said:


> ...so are you suggesting that cable companies are utilizing an electrical phenomenon unknown to modern science?


 


  from my point of view - they don't know themselves what actually makes some usb cables sound better than others. my guess is that they find needed combinations almost by simple substitution experiments.
  BUT marketing requires that these kind products of products should have a scientific explanation of the effect.
  so they have to compose a "bla-bla legend" in order to just have one.


----------



## Willakan

It's a cute idea, the cable companies doing wonderful trial and error experiments with unmeasurable factors to strive for ever better audio for the devoted audiophiles. It's discredited by the fact that people can only tell the difference between their cables when they know what they're listening to.


----------



## DaBomb77766

Quote: 





kr0gg said:


> from my point of view - they don't know themselves what actually makes some usb cables sound better than others. my guess is that they find needed combinations almost by simple substitution experiments.
> BUT marketing requires that these kind products of products should have a scientific explanation of the effect.
> so they have to compose a "bla-bla legend" in order to just have one.


 


  There's also the scientifically proven and well-backed up theory that it's simply a placebo effect.  The placebo effect is extremely powerful.  And the human mind is very good at fooling your senses.  How else would ghost "sightings" and "paranormal events" be so common?


----------



## Bostonears

dabomb77766 said:


> How else would ghost "sightings" and "paranormal events" be so common?


 

 I only see ghosts when I'm listening to music through Litz-constructed digital cables.


----------



## dvw

Quote: 





vandaven said:


> The problem is that people are not willing to accept that whatever happens between the audio interface and the computer is a controlled digital system with no "esoteric" possibilities.


 

 Agreed 100%. There is not even a valid theory that the "value" of the signal can be changed *selectively*. This is like if I put a $100 check in my pant pocket and go to the bank. The bank will only convert that check for $99 because the check has been wrinkled in my pocket.


----------



## Hennyo

This thread has gone leaps and bounds, and nearly every person here does seem to have a valid point. I think that that multiple people in the room should conduct true blind tests, preferably on some mid-tier equipment so we can assume there are no 'bottlenecks.' It is true that many inventions have taken place without the mathematical backup available at the time, rather they were made on good impulse and common sense.
   
  While cables probably don't carry to much weight in the 'undiscovered science' category, multiple people here can blind test A - B - C many times over a given 5 minute period. If we all posted our multiple blind testing in a thread somewhere, not only would it prove weather or not weather digital cables are fact or fiction, but also be a great place to determine where/what systems cables make the most difference on.
   
  A cumulative 5 hours of work divied out to a group of individuals will could go a long way for the community. : ) The conclusion would be invaluable to anyone curious around the world.. Until then, many posts are flaming. Some subjectively say 'yes', and some scientifically say 'no or very little'. The current facts remain, people are continuing in greater numbers that they do make a difference, and well, the other crowd will claim they can't/don't, as there is a lack of (acceptable) scientific evidence. -For that crowd.
   
_Ultimately_ a series of blind testing or some dramatically new piece of evidence are the only ways to reach a conclusion. If no dramatic piece of evidence surfaces due to our misunderstanding of science or lack of knowledge thereof, the much easier way to reach consensus = Properly done blind testing is the same as scientific evidence. Especially across a consensus.
   
  Does the majority agree? If so, lets gather a list of people who'd wish to blind test, and over the next 45 days or w/e when people can, we will create a new thread with OP #1 being the blind testing videos given credit to each person.
   
  My 2 cents:
  The only requirements, across all demoers, should be what the head-fi community deems 'decent' equipment, preserving our quality listening during the blind tests and helping allow for no anomalies. This would be a control of sorts.


----------



## Hennyo

Nearly every person here does seem to have a valid point. I think that that multiple people in the room should conduct true blind tests, preferably on some mid-tier equipment so we can assume there are no 'bottlenecks.' It is true many inventions have taken place without the mathematical backup available at that time, rather they were made on good impulse and common sense.
   
  While cables probably don't carry to much weight in the 'undiscovered science' category, multiple people here can blind test A - B - C many times over a given 5 minute period. If we all posted our multiple blind testing in a thread somewhere, not only would it prove weather or not weather digital cables are fact or fiction, but also be a great place to determine where/what systems cables make the most difference on.
   
  A cumulative 5 hours of work divied out to a group of individuals will could go a long way for the community. : ) The conclusion would be invaluable to anyone curious around the world.. Until then, many posts are flaming. Some subjectively say 'yes', and some scientifically say 'no or very little'. The current facts remain, people are continuing in greater numbers that they do make a difference, and well, the other crowd will claim they can't/don't, as there is a lack of (acceptable) scientific evidence. -For that crowd.
   
_Ultimately_ a series of blind testing or some dramatically new piece of evidence are the only ways to reach a conclusion. If no dramatic piece of evidence surfaces due to our misunderstanding of science or lack of knowledge thereof, the much easier way to reach consensus = Properly done blind testing is the same as scientific evidence. Especially across a consensus.
   
  Does the majority agree? If so, lets gather a list of people who'd wish to blind test, and over the next 45 days or w/e when people can, we will create a new thread with OP #1 being the blind testing videos given credit to each person.
   
  My 2 cents:
  The only requirements, across all demoers, should be what the head-fi community deems 'decent' equipment, preserving our quality listening during the blind tests and helping allow for no anomalies. This would be a control of sorts.
   
   
  Quote: 





willakan said:


> It's a cute idea, the cable companies doing wonderful trial and error experiments with unmeasurable factors to strive for ever better audio for the devoted audiophiles. It's discredited by the fact that people can only tell the difference between their cables when they know what they're listening to.


 
  Correct, that would seem to be the general opinion. Lets test it.


----------



## Bostonears

hennyo said:


> _Ultimately_ a series of blind testing or some dramatically new piece of evidence are the only ways to reach a conclusion.


 

 But many people have their beliefs firmly entrenched, and prefer to keep it that way. They aren't interested in evidence to the contrary. No matter what test is devised, someone will find fault with it and claim that it doesn't apply to their gear, or to their ears, or to their music, or to their way of listening, or whatever.


----------



## jackmccabe

Quote: 





bostonears said:


> But many people have their beliefs firmly entrenched, and prefer to keep it that way. They aren't interested in evidence to the contrary. No matter what test is devised, someone will find fault with it and claim that it doesn't apply to their gear, or to their ears, or to their music, or to their way of listening, or whatever.


 
  Completely true, as has happened with practically all previous blind tests.


----------



## Hennyo

Quote: 





bostonears said:


> But many people have their beliefs firmly entrenched, and prefer to keep it that way. They aren't interested in evidence to the contrary. No matter what test is devised, someone will find fault with it and claim that it doesn't apply to their gear, or to their ears, or to their music, or to their way of listening, or whatever.


 
   
  Perhaps. However, their opinion will become as a dry husk in the wind (on both sides of the aisle) left to disintigrate all on its own, and the majority will have changed and evolved due to superior scientific thnking. A new consensus will be reached. Majority rules. Your post, while true, is no reason to not go after the truth... that's just an excuse not to even try pursuing truth at all. To not innately pursue truth is inhuman.
   
  To stay behind is human error. We're not doing it for the small % that won't change, we'd be doing it for the 99% that will.
   
  (Oh, and it would be a fun 
	

	
	
		
		

		
			





) We're here to share knowledge/experience, and have a good laugh with each other.


----------



## Hennyo

Quote: 





> Originally Posted by *jackmccabe* /img/forum/go_quote.gif
> 
> Completely true, as has happened with practically all previous blind tests.


 

 Jack, you're being sour, don't hinder people who want to conduct their own blind tests. You should be happy that we might be about to prove that cables make no difference! I would think you'd want us to conduct tests. Or are you the 1% that doesn't want to accept the possibility of a different outcome? Are you afraid of just the possibility that the consensus could show otherwise. I and others are trying to move forward Jack.
   
  And this would be a valid way to do so. Not to mention easy!


----------



## Bostonears

hennyo said:


> Perhaps. However, their opinion will become as a dry husk in the wind (on both sides of the aisle) left to disintigrate all on its own, and the majority will have changed and evolved due to superior scientific thnking. A new consensus will be reached. Majority rules. Your post, while true, is no reason to not go after the truth... that's just an excuse not to even try pursuing truth at all. To not innately pursue truth is inhuman.
> 
> To stay behind is human error. We're not doing it for the small % that won't change, we'd be doing it for the 99% that will.
> 
> ...


 

 I think it's great for people to conduct their own blind tests to decide for themselves what is the truth. But that doesn't mean a consensus will be reached. There's a reason why many audio forums ban discussions of double-blind testing, because such discussions invariably devolve into intractable arguments, rather than evolve into superior scientific thinking.
   
  In short, the testing is very worthwhile. The discussion of the testing is much less so.


----------



## Hennyo

Quote: 





bostonears said:


> I think it's great for people to conduct their own blind tests to decide for themselves what is the truth. But that doesn't mean a consensus will be reached. There's a reason why many audio forums ban discussions of double-blind testing, because such discussions invariably devolve into intractable arguments, rather than evolve into superior scientific thinking.
> 
> In short, the testing is very worthwhile. The discussion of the testing is much less so.


 

 Probably right. But at least we can post our videos. Perhaps consensus could be reached. To say it couldn't is really a blow to modern humans. Claiming people would rather remain ignorant. I can't accept that. Has the world become that passive, it's not willing to fight for what it believes in anymore. I'd like not to think so. We must post scientific finding, if someone injects more subjectivity into their decision while digesting it, that is that persons human error.
   
  To halt all progression because one person out of the many couldn't accept it. What truth is worth pursuing if we can take no action because argument will be had?
   
  While this is all philosophical, this is the debate that's just been posed. While it is valid and true, sometimes it must also be overlooked. That is if any one person really cares about the truth. (We all -99%- of us do). I beleive it's 100%. That 1% is just harder to make change.
   
  If they eventually can't, they must forfeit their argument. That person will end of being ignored, or in the cycle of evolution towards more perfection, die.
   
  Remember this is all philosophical, and is what was essentially proposed by Bostonears. In summary, while absolutely correct, human beings must still strive for the truth. Science is what humans perceive as truth, so lets conduct some science! And have fun doing it, regardless of the outcome!


----------



## jackmccabe

Quote: 





hennyo said:


> Jack, you're being sour, don't hinder people who want to conduct their own blind tests. You should be happy that we might be about to prove that cables make no difference! I would think you'd want us to conduct tests. Or are you the 1% that doesn't want to accept the possibility of a different outcome? Are you afraid of just the possibility that the consensus could show otherwise. I and others are trying to move forward Jack.
> 
> And this would be a valid way to do so. Not to mention easy!


 
  I have performed many of my own tests and come to my conclusion.
  I have seen many other people perform their own tests and come to the same conclusion.
  In most blind tests people can't tell amps or dacs apart let alone cables.


----------



## Hennyo

Quote: 





jackmccabe said:


> I have performed many of my own tests and come to my conclusion.
> I have seen many other people perform their own tests and come to the same conclusion.
> In most blind tests people can't tell amps or dacs apart let alone cables.


 
  Ok, we know your opinion. There are many people posting here, not just you and me, so please stop responding to every single one of my posts. Now please let us continue to scientifically as possible pursue the truth. We all know each others opinion. We've moved past that and are now trying to get to the bottom of it at this point.


----------



## jackmccabe

Quote: 





hennyo said:


> So you're clearly unwilling to accept change even if evidence and popular findings indicate otherwise. There's No need to tell us we can't do something. Please let us do our thing and now let us come to our own conclusions. Even if they don't agree with however you've obtained yours. Nobodies wants to flame here. We just want to get to the bottom of it.
> 
> I've heard many different dacs/amps and found them all to sound staggeringly different in terms of sound.
> 
> ...


 
  I am completely willing to reconsider my opinion if repeatable and valid evidence and tests are provided, but this will never happen.
  It is far more likely there are no audible differences between cables than all the current measurements, tests and science we know is flawed.
  Can you provide any other reason you believe cables make a difference than because you hear one?


----------



## chinesekiwi

So why is there 33 pages of this?
  The pure answer there is no difference, unless the cable is broken or on the extremely rare chance there is interference.


----------



## Hennyo

Chinesekiwi:
   
  Oh well, all's well that ends well I guess. I guess nobodies interested in recorded blind tests anyways, and op's or mods should just close down this thread, only to have another identical thread posted tomorrow or the next day by somebody else. _But of course_ the testimonies here are all false and biased for their cables. I suppose we should not try to blind test ourselveson a wide scale to see for sure weather differences do exist. Lol. In the end i guess it's the same as before. We'll enjoy the obvious cleanliness and improvements we do not have to strain to hear.
  
  Quote: 





jackmccabe said:


> I am completely willing to reconsider my opinion if repeatable and valid evidence and tests are provided, but this will never happen.
> It is far more likely there are no audible differences between cables than all the current measurements, tests and science we know is flawed.
> Can you provide any other reason you believe cables make a difference than because you hear one?


 
   
  Have you not read this entire thread? In-case you haven't noticed the last 5 pages have been attempting to tackle just that. I and others have explained myself over and over again, but you're blind. You've contributed nothing, have not the slightest inkling to contribute, and to top it off, troll every single thing I say.
   
  I'm out. I don't want to be banned and this is disgusting. Enjoy your thread Jack. Hopefully you'll stop posting as well if everything's going to be a 3 sentence sluff-off.. I thought blind tests were a wholehearted and good idea. Again, the trolling of good information is just too hard.
   
  I hope the others pursue. They were making headway.


----------



## chinesekiwi

As I said, unless the cable has been tampered with deliberately (in which for example some headphone cables from some manufacturers do) to cause a distortion in sound, there is no difference. Testimonies mean nothing if the measurements don't stack up.


----------



## uelover

Haha Hennyo. Let's stay out before you get flamed like many people before us.
   
  Go search on how the foobar/amarra/puremusic users were called names and scorned at, exactly the same way jacmmcable did to us here.
   
  Let them use stock USB cables and use itunes for playback.
   
   
  This is a free world and they have every right to do so =)


----------



## The Pell

As much as I am a non-believer, I would love nothing more than for one of the folks in here to prove me wrong and rub it in my face. A good "told ya so" never hurt anyone. But, so far we have something somewhat scientific from the non-believer camp, and absolutely nothing from the cable lovers. Lets see some tests!


----------



## Willakan

Blind testing would be interesting - looking on the internet, whilst there are various tests for HDMI cables, there are few for audio cables. I found a website that appeared to be doing blind cable tests - but then it turned out that they were sighted, all parties involved expected to hear a difference in advance, and the site also hosts a review suggesting that the cable between your external hard drive and your computer makes a difference, which is quite frankly pants-on-head insane.
   
  The problem is, I'm not sure who is going to heed the results. Many people will dismiss them out of hand because "blind testing is stressful 'cos Stereophile said so" - the only people likely to have their opinion changed by such tests are a minority. Additionally, who is going to do the tests and buy the cables? The kind of USB cables that are regularly touted as "the ones that make a big difference" are hardly cheap.
   
*EDIT*: Just saw the foobar comment, a bit misleading as at that time Itunes had a badly implemented digital volume control and I think didn't provide bit-perfect playback, which Foobar did. As a measurable and sizable difference, this could have resulted in an audible improvement (Itunes has been fixed since then and now provides bit-perfect playback properly configured) The stuff with Amarra ect seems to be suggesting that you can improve on bit perfect inside the computer, which doesn't really make any sense at all - does it bribe your SATA cables?


----------



## drez

at the risk of repeating myself, you can measure jitter, and managing jitter is an essential part of the design of contemporary electronics.
   
  Most cable manufacturers don't measure jitter, and yet claim that their cables are effective at reducing jitter.
   
  Maybe Tyll from Headroom will do us all a favor and do some comparative jitter measurements.  Till then its pretty inaccurate to compare by ear.  Personally I find it difficult enough to tell between my analogue and 75 ohm interconnect, as well as my DI from my Essence ST as transports.  
   
  Therefore a more systematic and technical approach would greatly help us all to make sense of things.


----------



## jackmccabe

Quote: 





uelover said:


> Haha Hennyo. Let's stay out before you get flamed like many people before us.
> 
> Go search on how the foobar/amarra/puremusic users were called names and scorned at, exactly the same way jacmmcable did to us here.
> 
> ...


 
  Please provide some evidence and then I will stop "flaming" you.


----------



## Prog Rock Man

With regards to earlier discussion about the idea that there is an unknown factor in cables that causes sund quality differences we should consider -
   
   - no cable company has found a new property in cables, all the properties they discuss have been known since the 19th century, even skin effect.
   
   - no cable company has had their science peer reviewed or accredited by any authority, such as a university.
   
   - no cable company has published any ABX or even blind test results, so they miss out part of the evidence as to the audiblity of cable differences
   
   - no cable company can explain the inconsistency in how each has its own design of cable, often criticises other's design and yet all improve sound
   
  - no cable company can link measureable differences in cables to changes in sound quality (one that tried had to withdraw that claim as there was insufficient proof when challenged)
   
  http://www.head-fi.org/forum/thread/556398/cables-the-role-of-hype-and-the-missing-link
   
  With regards to USB cable blind testing, Milosz has conducted one and it was negative (results and test description to be published on his website) and I did one, in as much I set one up and then stopped after about 5 changes as I knew I was guessing and could not tell any difference. So it is not rigourous enough for me to have ever published it, but I tried and see no reason to so so again, especially since I have two available DACs and various USB cables and have never heard a difference with any cable changes.


----------



## dvw

Quote: 





prog rock man said:


> - no cable company can explain the inconsistency in how each has its own design of cable, often criticises other's design and yet all improve sound


 

 Actually, if they can provide an example of how a bad design of a spec compliant cable can ruin the sound, that will be a good start. If R&D is actually done there should be plenty of failed designs.


----------



## Prog Rock Man

Yes, a cable either works or it does not. It cannot affect sound quality such as treble, bass etc.
   
  Thing is, some cable companies claim extensive R&D and some have been on the go since the 1970s. Surely after all that time and research we would have a clear idea as to how a cable, any cable affects sound quality. But we don't.


----------



## tkteo

I admit to buying "audiophile" quality power cords and interconnects to connect my equipment ever since I got started into hifi audio.
   
  I have held off on getting the higher end cables. But the more I read, the more question whether, at the least, paying the often exorbitant prices really make a difference, as compared to upgrading disc player, amp, and headphone.
   
  Well maybe I am paying more for the more expensive cables because of the materials used (e.g. copper with more "nines" or silver) but that is me paying more for materials and not better sound.
   
  The idea of a USB cable costing hundreds to thousands of dollars is really scary.


----------



## drez

I wouldn't rule out the possibility of digital cables affecting audio quality outright.  Jitter is a real scientific phenomenon in digital signal transmission and it can have real effects no the distortion of a piece of equipment.  The degree of error is dependent upon the sampling rate the higher the frequency, AFAIK, the lower the jitter tolerance of the receiver chip.  A cable that works fine at 44.1 kHz might start introducing artifacts at 192 kHz - I have witnessed this with an overpriced coax I just bought.  The artifacts tend to be most noticeable in the treble, don't ask me why.  Having witnessed this I think it is perfectly reasonable that some USB cables in some setups might improve sound quality.
   
  Problem is that cable manufacturers don't seem to need to publish any actual performance figures for their cables, so it is down to audiophiles to try and tell them apart with their ears (and unfortunately often their eyes and little brains).  Until someone actually does some concrete testing we are, I'm afraid stuck with this form of imprecise "research," which to be honest seems to be how many cable manufacturers seem to develop their products also, along with plenty of creative [mostly fictional] writing for marketing campaigns.  It's not an appealing prospect but for the time being we have to put up with it, or not...


----------



## BlackbeardBen

Quote: 





drez said:


> I wouldn't rule out the possibility of digital cables affecting audio quality outright.  Jitter is a real scientific phenomenon in digital signal transmission and it can have real effects no the distortion of a piece of equipment.  The degree of error is dependent upon the sampling rate the higher the frequency, AFAIK, the lower the jitter tolerance of the receiver chip.  A cable that works fine at 44.1 kHz might start introducing artifacts at 192 kHz - I have witnessed this with an overpriced coax I just bought.  The artifacts tend to be most noticeable in the treble, don't ask me why.  Having witnessed this I think it is perfectly reasonable that some USB cables in some setups might improve sound quality.
> 
> Problem is that cable manufacturers don't seem to need to publish any actual performance figures for their cables, so it is down to audiophiles to try and tell them apart with their ears (and unfortunately often their eyes and little brains).  Until someone actually does some concrete testing we are, I'm afraid stuck with this form of imprecise "research," which to be honest seems to be how many cable manufacturers seem to develop their products also, along with plenty of creative [mostly fictional] writing for marketing campaigns.  It's not an appealing prospect but for the time being we have to put up with it, or not...


 

 The problem is that jitter in the quantities in even half-competent gear has _not once_ been shown to be audible, and there has been at least one extensive study (perhaps more) showing that it has to be orders of magnitude higher than in normal competent gear to become audible.
   
  Anecdotal accounts are _not_ acceptable evidence.


----------



## jackmccabe

Quote: 





drez said:


> I wouldn't rule out the possibility of digital cables affecting audio quality outright.  Jitter is a real scientific phenomenon in digital signal transmission and it can have real effects no the distortion of a piece of equipment.  The degree of error is dependent upon the sampling rate the higher the frequency, AFAIK, the lower the jitter tolerance of the receiver chip.  A cable that works fine at 44.1 kHz might start introducing artifacts at 192 kHz - I have witnessed this with an overpriced coax I just bought.  The artifacts tend to be most noticeable in the treble, don't ask me why.  Having witnessed this I think it is perfectly reasonable that some USB cables in some setups might improve sound quality.
> 
> *Problem is that cable manufacturers don't seem to need to publish any actual performance figures for their cables*, so it is down to audiophiles to try and tell them apart with their ears (and unfortunately often their eyes and little brains).  Until someone actually does some concrete testing we are, I'm afraid stuck with this form of imprecise "research," which to be honest seems to be how many cable manufacturers seem to develop their products also, along with plenty of creative [mostly fictional] writing for marketing campaigns.  It's not an appealing prospect but for the time being we have to put up with it, or not...


 
  You mean they can't because they would show there isn't a difference.
  All cable measurements ever taken have shown that cables make no difference.


----------



## Willakan

I remember nick_charles naming some jitter studies - there are quite a lot of them. (following is from memory, unable to locate the study again, but should be largely correct) I read a paragraph at the end of one of them which summarised the results of the study and various others - this includes studies conducted with random people, trained listeners (which are generally a helluva lot better at hearing things than your average "golden ears") and some with a mixture. Quite a lot of them found that even with trained listeners, hundreds of ns (one was 300ns if I recall) of jitter was required to be audible - this is a gigantic amount of jitter.
   
  The study which involved people listening to square waves to try to hear jitter (as opposed to actual music) found they could only hear 30ns of jitter - still much more than most digital equipment - and this from listening to tones chosen for their ability to show up jitter! Just to put things in perspective, the not-particularly-special clock in the Asus Essence ST "audiophile" soundcard at £140 is rated at 200ps of jitter - that's ps, not ns, a picosecond being a thousandth of a millisecond.
   
  The bottom line is IMO, the salesmen trying to sell digital equipment discovered a problem - getting all the specs pretty decent wasn't too difficult - how do they make their product stand out? AHAH! We shall go to great lengths to eliminate jitter, which isn't really much of a problem to start with, and then rely on the general fallibility of the human ear to make up differences in sound signature! 
   
  Suggesting that CABLES would have an audible effect due to jitter is faintly ridiculous - the effect this would have on a problem that is probably already inaudible (unless your equipment is crap) is utterly minute.
   
  Besides, most half-decent DACs reclock and oversample to make the problem that's not even a problem even more irrelevant.
   
  As usual, talking about cables, jitter and audibility as if this cable will make it better is a horrible abuse of science (not that cable manufacturers would ever publish totally misleading BS to sell their products that do nothing aside from demonstrate just how well the audio-based equivalent of the placebo effect works)


----------



## nick_charles

Quote: 





drez said:


> I wouldn't rule out the possibility of digital cables affecting audio quality outright.  Jitter is a real scientific phenomenon in digital signal transmission and it can have real effects no the distortion of a piece of equipment.  The degree of error is dependent upon the sampling rate the higher the frequency, AFAIK, the lower the jitter tolerance of the receiver chip.  A cable that works fine at 44.1 kHz might start introducing artifacts at 192 kHz
> 
> *A bog-standard 75 ohm coax cable has a bandwidth of 100s of MHz if not a few gigahertz, normal digital audio signals at whatever sampling frequency are easy-peasy and Toslink has an even higher bandwidth ! - what you are getting mixed up with is the effect of jitter on audio frequencies not sampling frequencies, jitter does have a greater effect on higher frequencies and on higher bit-rates - jitter at the same magnitude will be more damaging on a 20K signal than on one at 1K, however as mentioed elsewhere jitter has to be at absurd levels (several 10s of ns) to create audible distortion. Jitter is just not something to worry about. There is not one verifiable case of jitter in the sub-ns level being audibly detected  - ever.  Worry about the government, the economy or the state of British tennis if you wish but not jitter, it is wasted worry
> 
> ...


----------



## upstateguy

Quote: 





> Originally Posted by *nick_charles* /img/forum/go_quote.gif
> 
> *Wavoman did some blind tests on digital audio cables, nobody could tell them apart !*


 


  I was there for one of the tests.  It was with a $1000 usb cable and Wavo's esoteric rig.  No one could tell it from a really cheapie (freebie) looking cable.  So what!
   
  Please stop confusing us with the facts.


----------



## High_Q

Guys.  I'm gonna need a break down of what when into the building of the $1000 usb cable(labor, parts, marketing, holy water etc).  Thanks.
   
  High_Q
   
  Quote: 





upstateguy said:


> I was there for one of the tests.  It was with a $1000 usb cable and Wavo's esoteric rig.  No one could tell it from a really cheapie (freebie) looking cable.  So what!
> 
> Please stop confusing us with the facts.


----------



## upstateguy

Quote: 





high_q said:


> Guys.  I'm gonna need a break down of what when into the building of the $1000 usb cable(labor, parts, marketing, holy water etc).  Thanks.
> 
> High_Q


 

 Hi High
   
  The only thing I remember was that it was very thick and heavy.  I remember remarking that it looked like it would put a lot of strain on a usb port.
   
  USG


----------



## High_Q

^Cost breakdown please.


----------



## jackmccabe

Quote: 





high_q said:


> ^Cost breakdown please.


 


  $5 - materials
  $5 - labour
  $990 - profit


----------



## upstateguy

Quote: 





jackmccabe said:


> $880 - Ingenuity, Design and Marketing
> $5 - materials
> $5 - labour
> $110 - profit


 
   
  FIFY


----------



## High_Q

Can you break down more please?
  
  Quote: 





upstateguy said:


> $880 - Ingenuity, Design and Marketing


----------



## upstateguy

Quote: 





high_q said:


> Can you break down more please?


 

  
  You've got a PM


----------



## svyr

high_q said:


> Can you break down more please?




I believe that's a euphemism for a word starting w f ending with d  (noun, 5 letters)


----------



## chinesekiwi

I run my rig using a sub $10 2RCA to 2RCA cable. As long as it's well constructed and (optional really but reassurance) shielded, it's fine, which it is. I'm even supporting the local economy as it's made here. Oh ain't I kind.


----------



## drez

so does higher sampling rate, given the same bit size, does not require a higher frequency digital signal, the recovery of which would have a lower jitter tolerance? (from what I understand).
   
  As per the high frequency artifacts why my DI is set to 192 kHz sampling rate, its either the interface or the cable, I currently can't verify which it is for now.  Sorry to confuse/mislead anyone.
   
  Personally I don't have too much of a problem with over-engineering, as long as it is actually effective in setting out what it claims to do.  
   
  IMO the aforementioned listening tests should be the primary means of debunking cables, as there are much easier ways to do this electronically.
   
  As was mentioned, if jitter isn't important then a whole lot of what digital interfaces and DAC architectures are designed around is also rubbish.


----------



## DaBomb77766

From what I understand, according to USB spec, the signal's frequency is 24.000 MHz.  So no matter what frequency the audio is, it will always be packaged up into data and transferred at a frequency of 24 MHz.  The difference between the frequencies used in audio is negligible compared to this...so I'd assume, though I'm not 100% certain, that the sampling rate of the audio will make no difference whatsoever to the quality of the transfer.  Not to mention that any sort of audio signal will always be of a lower bitrate than the USB 2.0 spec is capable of...


----------



## High_Q

The cable is just a transfer medium of the modulated signal, the decoding and its timing are done on the DAC itself, and it should be very accurate.  The data does not flow through the cable during play.  I think people are confusing it with an analog signal interconnect.  That's probably how people get bought into the scam. For example, just look at how video is streamed through network.  The data is fetched before it is decoded.


----------



## DaBomb77766

Quote: 





high_q said:


> The cable is just a transfer medium, the decoding and its timing are done on the DAC itself, and it should be very accurate.  The data does not flow through the cable during play.  I think people are confusing it with an analog signal interconnect.  That's probably how people get bought into the scam. For example, just look at how video is streamed through network.  The data is fetched before it is decoded.


 


  I'm not sure if that's how USB audio works though...any sort of network streaming also has error correction, while standard USB audio does not.  I don't think it fetches any data beforehand, I think it simply streams the raw data directly to the DAC.
   
  Not that it'd make any huge difference in the end though, either way...the margin of error here is pretty small.


----------



## High_Q

Come on, you are saying it is streaming and it is doing error correction?  I know error correction does take place with digital data once data is demodulate.  Also, when you say stream, you can say video is being steamed, but it is fetched and loaded to memory before the decoding process begins.  Audio works the same way, on my ipod there is a brief pause before play because of the hard drive lag, dated is transferred during the lag.
  
  Quote: 





dabomb77766 said:


> I'm not sure if that's how USB audio works though...any sort of network streaming also has error correction, while standard USB audio does not.  I don't think it fetches any data beforehand, I think it simply streams the raw data directly to the DAC.
> 
> Not that it'd make any huge difference in the end though, either way...the margin of error here is pretty small.


----------



## uelover

Quote: 





high_q said:


> The data does not flow through the cable during play.  I think people are confusing it with an analog signal interconnect.


 
   
  This is not true.
   
  USB audio works like SPDIF and everything is live-stream.
   
  There is no buffer like how computer deals with online audio/video stream.


----------



## chinesekiwi

Quote: 





drez said:


> so does higher sampling rate, given the same bit size, does not require a higher frequency digital signal, the recovery of which would have a lower jitter tolerance? (from what I understand).
> 
> As per the high frequency artifacts why my DI is set to 192 kHz sampling rate, its either the interface or the cable, I currently can't verify which it is for now.  Sorry to confuse/mislead anyone.
> 
> ...


 

 Uh, you can't sample what isn't there!
  Also not to mention there is ZERO practical use of 192kHz. The only reason it was invented was because the marketers wanted it. Really. What you doing is actually introducing sampling errors. Go read this entire topic: http://lavryengineering.com/lavry_forum/viewtopic.php?f=1&t=24


----------



## vandaven

Quote: 





uelover said:


> This is not true.
> 
> USB audio works like SPDIF and everything is live-stream.
> 
> There is no buffer like how computer deals with online audio/video stream.


 

 Absolutely untrue.
   
  Every USB audio interface is accessed via a buffer. It is not like S/PDiF.


----------



## uelover

Quote: 





vandaven said:


> Absolutely untrue.
> 
> Every USB audio interface is accessed via a buffer. It is not like S/PDiF.


 
   
http://www.hifi-advice.com/USB-synchronous-asynchronous-info.html


----------



## High_Q

This is the quote from your link:
   
*The bottom line? Use your ears, not only your mind, and listen to the computer/transport/interface/dac of your choice and don't let the technical mumbo jumbo get too much in the way!*
   

 LOL, would not belive anything writton on the page, it's the first page that shows up on google search.  
   
  Did you miss this?
   
   
 *Asynchronous USB (not to be confused with asynchronous samplerate conversion) uses a clock housed near the dac (usually in the external dac's casing) and allows it to drive the converter directly, thereby not relying on the instable computer's clock. Well, someone who is technically more adept at this matter than me informed me that this is still not entirely true as the interface or dac is still somewhat dependent upon the stability of the PC's bus clock.  It is called asychronous because the dac's master clock isn't synchronized directly to any clocks within the computer. Instead, the dac is controlled by a (potentially high-precision) fixed-frequency clock. This clock controls the datastream from the computer to a buffer near the DA converter.*
  
  
 *The thing is: Asynchronous USB data transfer doesn't guarantee perfect sound. Well, technically speaking, it does. But bit-perfect transfer doesn't guarantee enjoyable sound. *
   
  ^Rediculous.  The whole read is play on words and jargons, you can tell the person does not know what he is talking about.  This is what you call marketing folks.
  Quote: 





uelover said:


> http://www.hifi-advice.com/USB-synchronous-asynchronous-info.html


----------



## svyr

>The thing is: Asynchronous USB data transfer doesn't guarantee perfect sound. Well, technically speaking, it does. But bit-perfect transfer doesn't guarantee enjoyable sound. 

async usb doesn't guarantee bit perfect transfer. That's BS. If you do have interface issues from the cable or the usb chip or something, these will show up as dropped samples (presumably corrupted and discarded after a crc check).

Since async transfer mode doesn't have retransmission on error, it can't guarantee bit-perfect transfer...It can however minimize timing errors in the form of jittteeer (bulk mode is still better, since the info at the DAC end comes out bit perfect/what left at the PC end  )


Otherwise, I don't find their comment particularly criminal, heh, I think the website means it in the "don't necessarily trust bs marketing and test it for yourself" way, which is not a bad way 'as long as you're happy'. On a bright stax system, I was more happy with a NOS dac sound than I was with Benchmark DAC1, so their comment makes sense to me (although that's not async usb, but you get the point)... That said, a decent DAC instead of the NOS one would have done better so maybe there is a point to cut the romantic BS where it grows since NOS dac marketing is full of fluffy bs as well


----------



## High_Q

Expand on that or examples?  What is the cause of the interface issues?
  
  Quote: 





svyr said:


> >The thing is: Asynchronous USB data transfer doesn't guarantee perfect sound. Well, technically speaking, it does. But bit-perfect transfer doesn't guarantee enjoyable sound.
> 
> async usb doesn't guarantee bit perfect transfer. That's BS. If you do* interface issues *from the cable or the usb chip or something, these will show up as dropped samples.
> 
> ...


----------



## svyr

high_q said:


> Expand on that or examples?




that was meant to say 'do have interface issues'. Other examples are well elaborated on in the usb spec for bulk mode and isochronous transfer (incl async, sync and adaptive modes). 

>That said, a decent DAC instead of the NOS one would have done better so maybe there is a point to cut the romantic BS where it grows since NOS dac marketing is full of fluffy bs as well 


That was just referring to DAC1 sounding serrating, and NOS dac having a rather high noise floor/NFB-10WM being more detailed, but not sounding harsh. (although I did have my own issues with NFB-10WM too  ). A lot more of the difference seems down to preference/analog out stage.


----------



## High_Q

Ok, if you do have inteface issues.  Can you state the probability, and the causes?
  
  Quote: 





svyr said:


> Quote:
> 
> 
> 
> ...


----------



## svyr

high_q said:


> Ok, if you do have inteface issues.  Can you state the probability, and the causes?




for async, it could be anything that will cause the samples past usb chip on the DAC to not be the same as the input file's  
Causes and probability - no idea, I don't particularly believe in magical USB cables, so I guess it'd have to be async issues (clock problems maybe, usb controller problems, or protocol issues itself, since it sounds like async adjusts the flow of data in a feedback loop of some sort basically letting the PC know whether to slow down or speed up the data flow rate. I guess if (the mot wasn't simplifying and) the clock is fast enough, you shouldn't lose any samples)
The later is speculation and is based on http://www.head-fi.org/forum/thread/258551/how-does-usb-audio-transfer-work#post_3273142 . You can check with the MoT how it actually works  . All I can tell is bulk mode transfer is by design removed from these issues as it just does vanilla data transfer the way your usb HDD will with error checking and re-transmission on error  (see the post a few pages back)


----------



## vandaven

Quote: 





uelover said:


> http://www.hifi-advice.com/USB-synchronous-asynchronous-info.html


 


  Of course it's buffered, but not inside the audio interface:
   
  http://www.mhsecure.com/technotes/v5MixerOverview/CoreAudio.html


----------



## uelover

Quote: 





vandaven said:


> Of course it's buffered, but not inside the audio interface:
> 
> http://www.mhsecure.com/technotes/v5MixerOverview/CoreAudio.html


 

   
  Quote: 





high_q said:


> Come on, you are saying it is streaming and it is doing error correction?  I know error correction does take place with digital data once data is demodulate.  Also, when you say stream, you can say video is being steamed, but it is fetched and loaded to memory before the decoding process begins.  Audio works the same way, on my ipod there is a brief pause before play because of the hard drive lag, dated is transferred during the lag.


 


  Yes. It is buffered on the PC/Mac side but not on the DAC side.
   
  The link you quoted touches on audio input from external audio devices to a mac. The mac is on the recipient end and thus buffering could occur.
   
   
  I am answering High_Q's statement as he likened USB audio streaming to online video streaming.


----------



## vandaven

It's an I/O buffer. Thus on both sides. A buffer for the input and a buffer for the output. Of course not inside the device. I referred to buffers way earlier in this thread. For example, a buffer underrun would be the result of a too small buffer size in relation to cpu / bus clock deviation. If you only listen to the music (without recording it, like I do), you normally never worry about the buffer latency. In case you need proof, I could post you some evidence. It's easily measurable, as Pro Tools (with an Avid interface) has I/O buffer compensation. Thus, a re-recorded impulse will only show the latency induced by the converter and the core audio system on any 3rd party device.


----------



## 00940

You're still at it after 36 pages ? And not a single one of you living in the English speaking world was able to locate the January issue Hi-Fi news (in which Paul Miller apparently demonstrates through measurements that different usb cables cause different levels of jitter in the DAC they feed) ? 
   
  You really don't value your time... you could be debating what level of jitter is audible, imagine how much funnier it would be  
	

	
	
		
		

		
		
	


	



   
   
  PS: there are buffers in modern SPDIF receivers.  
	

	
	
		
		

		
		
	


	




   Those are actually working in a very similar way to the buffers in the most common USB receivers (but not in the same way as the buffers inside asynchronous usb receivers... ooh the joy of multiple protocols on the same interface); that allowed TI to share the SPACT technology in between their spdif receivers (dir1703) and usb receivers (early pcm270*). The buffers inside the computer are pretty much irrelevant to a discussion about usb cables on the other hand.


----------



## vandaven

That is indeed very interesting. Is there any possibility to view that article, as I did measurements with different usb cables on multiple usb audio interfaces that did not show any noticeable difference between the cables.


----------



## 00940

I wish... Someone sent me the article of December 2010, in which Paul Miller shows the effects of various aspects of the source computer on the jitter of an usb dac but I couldn't locate till now the January 2011 article. All I've got are second hand accounts on the web.
   
  It's possible to suscribe to their digital edition for 19£, for a year + access to the archives, but apparently not to buy a single digital issue.


----------



## tkteo

Uh, if someone scanned it and posted the relevant page on here, it would be against copyright, right? (no pun intended)


----------



## uelover

duplicate posts.


----------



## uelover

@vandaven: I understand very well the buffering that takes place for audio in/out on computers. I am merely pointing out that the *bulk* of the link you quoted explains on Coreaudio's role in audio inputs. I am in nowhere saying that buffering does not take place for audio output. Please don't read things with a colored lens.
   
   
  This is a misstatement suggesting that a similar process is taking place on the DAC that I feel the need to correct - there is nothing being fetched and loaded into 'any' memory on a DAC before decoding starts and for USB audio, data is continuously flowing from the computer to the DAC:
   
  Quote: 





			
				High_Q said:
			
		

> The cable is just a transfer medium, the decoding and its timing are done on the DAC itself, and it should be very accurate.  *The data does not flow through the cable during play*.  I think people are confusing it with an analog signal interconnect.  That's probably how people get bought into the scam. For example, *just look at how video is streamed through network.  The data is fetched before it is decoded.*


 
   
  Quote:


			
				High_Q said:
			
		

> Come on, you are saying it is streaming and it is doing error correction?  I know error correction does take place with digital data once data is demodulate.  *Also, when you say stream, you can say video is being steamed, but it is fetched and loaded to memory before the decoding process begins*.  Audio works the same way, on my ipod there is a brief pause before play because of the hard drive lag, dated is transferred during the lag.


----------



## High_Q

That's is true, data does not get prefetched to the DAC. Apologies if it has caused any confusion, I've realize what I have written after uelover pointed it out.  I typed it out right after I woke up, my brain was a little fuzzy.
	

	
	
		
		

		
		
	


	




  For some reason, I have mixed up data transfer and streaming though network, where data gets transferred first, then gets loaded, then decoded for the output device.  But, yes, data get's loaded to memory and it is decoded from the external DAC.  Data must be transferred through usb from the pc to be decoded by the external DAC.


----------



## DaBomb77766

I'm pretty sure it's a given that different cables can have different levels of jitter.  After all, isn't the USB spec designed to reduce jitter as much as possible?  The real question is whether or not the miniscule differences in jitter from one cable to another is audible or even measurable in the audio signal.


----------



## chinesekiwi

Quote: 





dabomb77766 said:


> I'm pretty sure it's a given that different cables can have different levels of jitter.  After all, isn't the USB spec designed to reduce jitter as much as possible?  The real question is whether or not the miniscule differences in jitter from one cable to another is audible or even measurable in the audio signal.


 
   
  Measureable? probably. Within the limits of human hearing? laughable.
 Jitter and stereo crosstalk are non issues in audio these days.


----------



## Prog Rock Man

Quote: 





00940 said:


> You're still at it after 36 pages ? And not a single one of you living in the English speaking world was able to locate the January issue Hi-Fi news (in which Paul Miller apparently demonstrates through measurements that different usb cables cause different levels of jitter in the DAC they feed) ?
> 
> You really don't value your time... you could be debating what level of jitter is audible, imagine how much funnier it would be
> 
> ...


 



 That Paul Miller finds a difference is only part of the issue. Cable makers do that all of the time, it is part of their marketing, our cable is different so it is better. The latter part being suggestion. I take it Paul Miller has no evidence of audibility.


----------



## 00940

you guys are so predictable.
   
  Obviously, the differences are measurable at the analog output of the DAC; that's by analyzing the audio signal at the analog output that jitter is most commonly measured today (as it doesn't require to open and hack the DAC unit under test).
   
  Paul Miller's tests indeed don't establish audibility by themselves (did anyone say that, certainly not I ?). They deal with whether or not USB cables have various levels of performances and up to what point. It's however enough to prove wrong all the guys who seem happy to just repeat ad nauseum "it's all digital, cables can't possibly make any difference, blah blah".
   
  However, by establishing the actual differences in between cables, those tests either allow to dismiss the audibility of those variations in technical performance or not, in relation with jitter audibility baselines established best through DBT.
   
  Which brings me back to my original statement: usb cables do make differences, but those differences are likely too small to be audible. I'm just waiting to get the figures from the article to be confirmed in my opinion.


----------



## Willakan

This article isn't hosted anywhere on the internet, only seems to exist in print


----------



## svyr

willakan said:


> This article isn't hosted anywhere on the internet, only seems to exist in print




you can get the december issue (arrrg, matey...  ) but it errr kinda says (p94) interconnects/etc in the jan issue and no one has 'arrr, mateyed' that yet  .
Maybe we can all chip in $2 to get the Jan issue for the lolz. (provided they accept paypal, since there is no way in hell anyone reasonable should give them their CC details  since chances are they're not securely processed or stored . At the very least the subscription site is broken and displays 'Text goes here' lol and the subscription issue preview site section says 'you don't have access to the subscription material' without showing anything (eeeh,ok, what's the point of a preview then))
On a sidenote, there are at least 5 ads for cables in the issue, and at least 1 usb. (ADC) (there's an ad on every second page lol, it's like the hi-fi equivalent of a fashion magazine  )


----------



## drez

hmm yeah looked at the site, $31 AU isn't much but I'm not interested in most of the crap in hifi magazines.


----------



## Prog Rock Man

Quote: 





00940 said:


> you guys are so predictable.
> 
> Obviously, the differences are measurable at the analog output of the DAC; that's by analyzing the audio signal at the analog output that jitter is most commonly measured today (as it doesn't require to open and hack the DAC unit under test).
> 
> ...


 



 I totally agree with your points 0094, I just wanted to confirm whether or not there was any comment on audibility.


----------



## dvw

I am having a little problem understanding the jitter in the streaming vs jitter in the playback. Can someone explain this to me.
  Let's assume for ease of understanding a recording is recorded at 44KHz and this recording should be played back at 44KHz and not 44.1KHz. If not this will cause a buffer under run.
  The USB2.0 is streamed at 480Mbps. How is this frequency related to the playback clock? How is the exact playback clock recovered?
  If the playback clock is not recovered from the streaming/USB clock, how is jitter in the USB clock affect playback clock?
  If it does, will playing at a lower speed (USB1.1) or higher speed (USB3.0) make any difference?


----------



## labrat

Delete


----------



## 00940

Quote: 





dvw said:


> I am having a little problem understanding the jitter in the streaming vs jitter in the playback. Can someone explain this to me.
> Let's assume for ease of understanding a recording is recorded at 44KHz and this recording should be played back at 44KHz and not 44.1KHz. If not this will cause a buffer under run.
> The USB2.0 is streamed at 480Mbps. How is this frequency related to the playback clock? How is the exact playback clock recovered?
> If the playback clock is not recovered from the streaming/USB clock, how is jitter in the USB clock affect playback clock?
> If it does, will playing at a lower speed (USB1.1) or higher speed (USB3.0) make any difference?


 
   
  The answer is "it depends". The problem is indeed to match two clocks : the sending or streaming clock and the playback clock. To make things easy:
   
  In some USB audio protocols, the playback clock is based upon the streaming clock. The playback clock will vary over time to adapt (which means keeping a relatively constant relationship) to the incoming clock in order to avoid the small fifo buffer running empty or overflowing (it's no big deal for audio playback if we play 44.1khz material a bit slower or a bit faster, as long as it doesn't change quickly). If it is properly done, the recovery process will smooth out most of the jitter of the streaming clock. The final jitter of the playback clock (the one that could possibly matter) will depend on the quality of the clock recovery process and on the quality of the streaming clock (as we can't expect the recovery process to be perfect), as well as on the quality of the hardware implementation.
   
  In another USB audio protocol (the famous asynchronous one), the playback clock is in charge and the usb receiver will signal the source computer to adapt its streaming of data if the buffer is nearing emptiness -  overflowing. The jitter of the playback clock can only be attributed to the quality of the local clock (which can vary quite a lot depending on hardware implementations), the jitter of the streaming clock becoming irrelevant.
   
   
  Did you read those articles ? They might clear up some of your questions:
   
  http://www.eetimes.com/design/audio-design/4009467/The-D-A-diaries-A-personal-memoir-of-engineering-heartache-and-triumph
  http://www.eetimes.com/design/audio-design/4009466/Do-we-use-an-existing-USB-core-How-large-should-the-FIFO-be-The-D-A-Diaries-Part-2
  http://www.eetimes.com/design/audio-design/4009528/Meeting-the-Distortion-Goals-The-D-A-Diaries-Part-3-of-3
   
  This one is interesting too, a bit too complicated maybe: http://www.audiomisc.co.uk/Linux/Sound3/TimeForChange.html


----------



## dvw

Thanks. I think I understand now. I was under the impression there is only one class of USB audio device that behaves somewhat like RTP/RTCP with embedded clock in the packet instead of the bit stream. In reality, the clock performance is really dependent on the implementation of the clock recovery circuit rather than a standard based solution.
   
  The playback clock depends on the implementation will have a varied degree of jitter and that should dominate over any jitter generated by the cable. And this jitter cannot (or unlikely) be reduced because it's caused by the differential of the receiver and transmitter. Well, at least that's my conclusion.


----------



## High_Q

Guys, I don't really see much point to this discussion if you do not have much grasp of the technology. I think designing a usb circuitry will give you good enough insight, and all others claiming cable issues without real understanding is really bothering me.  It just seams like a waste of time.  Anybody comp E?  Comp Es should have sufficient knowledge to explain all this.  As a EE(with limited knowledge of CE), if you cannot explain how the tech works, you do not have the credibility to make assumptions on the causes, and no, what you read on google or forums doesn't count.
	

	
	
		
		

		
		
	


	




  My 2 cents.


----------



## leeperry

hehe, the thread that will never die 
	

	
	
		
		

		
		
	


	



   
  I really wish that all the USB cables sounded the same, this would have saved me a lot of headaches...but luckily after trying zillion cables ranging from $1 to $150, my fav sounding cable costs $5, hallelujah! And yes, it sounds noticeably clearer and better than the others. YMMV, I guess 
	

	
	
		
		

		
		
	


	



   
  I've personally come to the conclusion that the ppl who sell $150 USB cables are crooks, that the $1 cables are junk...and that $5 will get you high purity copper, proper shielding and a good twisted pair yadayada..


----------



## travisg

Just found out that my Locus cables do make a difference. Stoked.


----------



## IPodPJ

Quote:


leeperry said:


> I've personally come to the conclusion that the ppl who sell $150 USB cables are crooks


 

 Regardless of your opinion of how any cables sound, cables take time to build by hand.  People charge for their labor.


----------



## leeperry

> Originally Posted by *IPodPJ* /img/forum/go_quote.gif
> 
> cables take time to build by hand.  People charge for their labor.


 

 I wasn't mentioning those +$1K USB cables that take 2 weeks to manufacture(or so they say), I'm talking about the top of the range WireWorld's for instance...and no, they're not built by hand. They're made in China for a few bucks top. I let you imagine what kind of markup is made on those. It's legal stealing, nothing else.


----------



## vandaven

Hum, it's really nice that so many contribute with opinions, or the opinions and tests of other people. But that just doesn't help at all.
  As some of you might know, I did tests which led to my opinion, I was not opinionated from the beginning. 
   
  To really contribute to this thread, post some hard data. It's simply not enough to say "I have a Audioquest / Locus / Wireworld / Oyaide cable and it contributes to my system!". That's like boasting "I saw a pink dragon yesterday". It's also not enough to simply discuss papers and theory. If anybody out there honestly wants to convince me or anybody else who is referred to as a "heretic" or "skeptic", go and re-record the signal from your audio interface. Even if you only have a standard line-in on your computer, it's enough to show a significant difference on inverse summing comparison.
   
  If you don't have the measurement possibilities:
   
  As already stated, I can offer a test sequence that you can play back, record, and send me via internet, so I can align it sample-precise and I will do my best to analyze it.
   
  Thanks.


----------



## svyr

WRT audbile jitter levels, http://www.3daudioinc.com/3db/showthread.php?12836-Grekim-and-Ethan-test-dither-jitter-A-D Ethan Winers and other AES presenter/contributor people have already been on the topic. (also worth looking at https://www.youtube.com/watch?v=BYTlN6wjcvQ and http://www.ethanwiner.com/aes/ as linked to before). I'm sure if you look further, you'll find more info about audible levels for music and tones.


----------



## leeperry

yea, USB jitter when using isichronous USB controllers is a tale to scare little children off.


----------



## throzen0303

I tried the Forest Cable, seems to make no difference at all, is it my setup not good enough to show the difference? or is the cable


----------



## Shike

Quote: 





throzen0303 said:


> I tried the Forest Cable, seems to make no difference at all, is it my setup not good enough to show the difference? or is the cable


 


  You're missing the 3rd possibility: there's nothing wrong with the cable, but it doesn't make a difference over another.


----------



## drez

honestly I think any [unproven] difference a USB cable might make pales in comparison to the differences a) getting a better asynchronous transport or b) considering clock irregularities introduced from the computers USB controller as well as hardware/software latency issues.
   
  The result of adding an audiophile USB cable could quite possibly be a drop in the ocean - or have no significant improvement in jitter performance at all.
   
  Found some interesting audiophool USB - related [overpriced] products that might resurrect this thread here.  As with all audiophile products technical info ( on the tX-USB) is skint, but at least this looks interesting.
   
  Does bring into question though the whole rationale of using an expensive USB cable to connect an otherwise flawed (or quite possibly adequate) USB controller and computer to a transport/DAC.
   
  Recently I just tested a blue jeans cable coax BNC, compared to an audiophile 75 ohm solid silver cored RCA,  between my AudioGD DI and NFB-10 ES and found absolutely NO reliably discernable difference - easy to test too - just flick back an forth between digital inputs with switch. 
   
  I can say with absolute certainty that it made no immediately obvious difference which could reliably be discerned, playing FLAC with my system, with my perfectly functional ears.  
   
  If I had someone else flick the switch (the music is not interrupted) I would not be able to tell at all when the switch was changed, let alone which cable was on or which was better.  QED


----------



## svyr

drez said:


> honestly I think any [unproven] difference a USB cable might make pales in comparison to the differences a) getting a better asynchronous transport or b) considering clock irregularities introduced from the computers USB controller as well as hardware/software latency issues.
> 
> The result of adding an audiophile USB cable could quite possibly be a drop in the ocean - or have no significant improvement in jitter performance at all.
> 
> ...




>Depth : 150 mmDual full size high quality oscillator

I loled.


----------



## drez

what don't you measure dimensions in "mmDual full size high quality oscillator" - its common practice in audiophile territory i thought?


----------



## BlackbeardBen

I use three of those cards.  One for my mouse to ensure the utmost accuracy, one for my external hard drives to ensure the highest quality transfers, and one for my USB card reader to make sure I don't lose any pixels when I load photos from my camera.


----------



## drez

do i detect satire?


----------



## leeperry

well, at some point I was using a cheapo poorly soldered USB3 Nec PCI-E card bought on ebay for dirt cheap...and it did change the sound to my ears on my TE7022L adaptive transport, compared to the Intel USB2 ports of my s775 mobo.

it seemed to make the SS wider but there was also a major lack of percussion in the bass...the old goofy story of "binary is only 0's and 1's" doesn't stand for digital connections...an out of specs USB data flow will go wreck on an adaptive transport.

I then decided to get a proper branded MSI USB3 board, and it sounded exactly like the mobo USB...narrower SS and deep percussive low end bass. The main problem w/ USB audio to my eyes is about getting proper gear that's within specs.


----------



## jackmccabe

Quote: 





leeperry said:


> well, at some point I was using a cheapo poorly soldered USB3 Nec PCI-E card bought on ebay for dirt cheap...and it did change the sound to my ears on my TE7022L adaptive transport, compared to the Intel USB2 ports of my s775 mobo.
> 
> it seemed to make the SS wider but there was also a major lack of percussion in the bass...the old goofy story of "binary is only 0's and 1's" doesn't stand for digital connections...an out of specs USB data flow will go wreck on an adaptive transport.
> 
> I then decided to get a proper branded MSI USB3 board, and it sounded exactly like the mobo USB...narrower SS and deep percussive low end bass. The main problem w/ USB audio to my eyes is about getting proper gear that's within specs.


 
  There is no way you can hear the difference between usb ports.
  Also unless a usb source is broken all dacs will work perfectly with them.
   
  I don't understand why people seem to think that usb cables/ports would effect the bass or soundstage.
  It is undeniable that usb sends 1's and 0's, so it is ridiculous to assume the signal is being distorted in a way that only effects certain elements, it's just impossible.


----------



## leeperry

> Originally Posted by *jackmccabe* /img/forum/go_quote.gif
> 
> There is no way you can hear the difference between usb ports. [..]
> I don't understand why people seem to think that usb cables/ports would effect the bass or soundstage.


 
   
  Oh great, you know what I hear better than I do. Are you a proud member of team "everything sounds the same to me"? You know, the team that says that all opamps sound the same, that a Realtek and a STX are impossible to DBT, that all PSU's sound the same(noisy SMPS or low ripple linear regulated = same!), etc etc. I really wish all the USB boards and USB cables sounded the exact same, this would have saved me a lot of headaches


----------



## tmars78

Quote: 





leeperry said:


> Oh great, you know what I hear better that I do. Are you a proud member of team "everything sounds the same to me"? You know, the team that says that all opamps sound the same, that a Realtek and a STX are impossible to DBT, that all PSU's sound the same(noisy SMPS or low ripple linear regulated = same!), etc etc. I really wish all the USB boards and USB cables sounded the exact same, this would have saved me a lot of headaches


 


  And you should know that "what I hear is truth" doesn't fly in this section of the forum. You know, I can tell the difference between USB hubs too. The ones I use on my computer now all seem to have a warrior drum playing faintly in the background, while the other ones didn't have it. Don't tell me its not there, cause I can hear it.


----------



## leeperry

tmars78 said:


> And you should know that "what I hear is truth" doesn't fly in this section of the forum. You know, I can tell the difference between USB hubs too. The ones I use on my computer now all seem to have a warrior drum playing faintly in the background, while the other ones didn't have it. Don't tell me its not there, cause I can hear it.


 

 I believe you, yo!
   
  The science side has been thorougly discussed in the previous pages, those threads feel like an endlessly broken record. If you've compared a lot of cables -IRL, and preferably on an adaptive transport- and if they all sounded the same to you, then life is good. Go out and have fun, life's too short.


----------



## Yoga Flame

Quote: 





jackmccabe said:


> There is no way you can hear the difference between usb ports.
> Also unless a usb source is broken all dacs will work perfectly with them.
> 
> I don't understand why people seem to think that usb cables/ports would effect the bass or soundstage.
> It is undeniable that usb sends 1's and 0's, so it is ridiculous to assume the signal is being distorted in a way that only effects certain elements, it's just impossible.


 

  
  I can attest to USB ports making an audible difference in some situations. Many computers have USB ports located in the front of the case for convenience. When I listened to a mini USB sound card plugged into this, the noise floor was much higher compared with the rear USB port.
   
  Often, these front ports are wired to the motherboard or internal add-on USB card with plain hookup wire. These unshielded wires pick up a lot of noise and pass it on to whatever gets plugged into the USB port. The noise may not be bad enough to distort the 1s and 0s, but it can still get into the analog circuitry of the DAC. That's why galvanic isolation is desirable, amirite leeperry 
	

	
	
		
		

		
			





?
   
  Another situation is when one USB port has power filtering and regulation and another just uses the onboard rails directly. This can make a difference with DACs that draw their power from USB. But well designed DACs with ferrite beads and built-in regulators should be affected less by this.


----------



## endless402

Quote: 





jackmccabe said:


> There is no way you can hear the difference between usb ports.
> Also unless a usb source is broken all dacs will work perfectly with them.
> 
> I don't understand why people seem to think that usb cables/ports would effect the bass or soundstage.
> It is undeniable that usb sends 1's and 0's, so it is ridiculous to assume the signal is being distorted in a way that only effects certain elements, it's just impossible.


 


 you're not accounting for the quality and stability of the power coming out of the port (especially if the device is powered by the port)


----------



## tmars78

Quote: 





endless402 said:


> you're not accounting for the quality and stability of the power coming out of the port (especially if the device is powered by the port)


 


  Yeah, but what they are saying, is that that would not affect treble or bass. It would be pops and clicks, or drop outs.


----------



## chinesekiwi

All said and done, the quality of the power supply, whether it be from mains or a power supply like in PC setups with soundcards, is far more important and has more of an impact than than 'audiophile usb cables'. Not to mention operating systems with the KMixer in Windows XP and before.


----------



## drez

Quote: 





jackmccabe said:


> There is no way you can hear the difference between usb ports.
> Also unless a usb source is broken all dacs will work perfectly with them.
> 
> I don't understand why people seem to think that usb cables/ports would effect the bass or soundstage.
> It is undeniable that usb sends 1's and 0's, so it is ridiculous to assume the signal is being distorted in a way that only effects certain elements, it's just impossible.


 

 I think a common tendency is to presume that these systems are much less complex than they are in reality.  Sure glitches are the most immediately obvious form of audible artifact from a digital signal transport system, but USB audio is (generally) not bulk mode transfer.  Digital audio is typically 44.1khz, correct me if I'm wrong but as far as I understand this is 44100 samples per second.  Jitter comes in a range of magnitures and types, so the distortion (jitter has different possible effects on different parts of the system) might be as low as 1/44100 of a second second or much larger depending on the effect of the jitter and is not necessarily manifest as a dropout.  Think of mp3 compression - a bad (high jitter) digital signal can effectively reduce the resolution of a digital signal (best analogy i can think of).  A lower resolution mp3 doesn't dropout or glitch consistently, the audible result is subjectively much more varied and inconsistent, even with large differences in resolution.  Having good dac and transport goes some way toward reducing the the audibility of these effects.
   
  There are a few interesting, if not entirely unbiased  discussions of the effects of jitter on DAC systems such as here, here, or here.  Note that none of these should be considered reliable sources as they are likely influenced by trade sponsors.  I also should not be considered a reliable source as I am an architect and not an electrical/sound engineer.


----------



## leeperry

drez said:


> I think a common tendency is to presume that these systems are much less complex than they are in reality.


 
  It's all a bunch of zeros and ones
	

	
	
		
		

		
		
	


	



   
  Anyway, a friend of mine just ordered a top of the range async transport, I'll put it through the cables test...hopefully, they'll all sound the same this time.


----------



## Prog Rock Man

Quote: 





jackmccabe said:


> There is no way you can hear the difference between usb ports.
> Also unless a usb source is broken all dacs will work perfectly with them.
> 
> I don't understand why people seem to think that usb cables/ports would effect the bass or soundstage.
> It is undeniable that usb sends 1's and 0's, so it is ridiculous to assume the signal is being distorted in a way that only effects certain elements, it's just impossible.


 



 There is a way people can hear a difference between USB ports, there are too many credible reports of sound quality differences to say that is not the case. The real question is why are there sound quality differences.
   
  I too do not understand how a USB cable can affect bass or sound stage. I don't think those who hear differences do either. I am also in the it either works or it does not camp. So are this lot and they should know........
   
  http://www.usb.org/home
   
  I would love to see an audiophile USB cable maker submit a cable for testing and peer reviews of their claims of enhanced sound qaulity. Even an endorsement by USB.org of such would be a start.


----------



## maverickronin

Quote: 





prog rock man said:


> There is a way people can hear a difference between USB ports, there are too many credible reports of sound quality differences to say that is not the case. The real question is why are there sound quality differences.


 

 USB power is pretty noisy and I can easily see it being different from port to port even on the same computer which could effect the sound if the isolation, smoothing, or PSRR on the DAC side isn't up to snuff or that USB port just happens to suffer from an unholy amount of noise which is enough to even overwhelm a good design.
   
  Unless a boutique USB cable has power smoothing caps or some other fancier power smoother built in it won't do jack about that either though.


----------



## uelover

I have an USB isolator coming its way and I will see if that will nullify the need for a 'good' USB cable/port.


----------



## Talos

Quote: 





> USB power is pretty noisy and I can easily see it being different from port to port even on the same computer


 
   
  And not just the power...  The data signal transmitted from a USB port consists of a waveform that the circuitry on the other end is going to try and interpret as a series of ones and zeroes.  If the signal is "clean" then that process should be quite unambiguous.  But if the data signal itself is "dirty" or "noisy", then you can imagine how that introduces complications into the process.  Ignoring for the moment what the the sonic consequences of any such "noise" might be, or just how much "noise" in the data signal is necessary for its consequences to be audible, there exists sophisticated equipment that electrical engineers can use to observe and quantify this "noise".
   
  Although I have not seen it myself, a friend with substantial credentials in the industry (he designs DACs, not cables!), who has done such measurements, has confirmed to me that there are some very significant differences between computers, and even in some cases between individual USB ports on one computer.  FWIW, he mentioned to me the Macs generally have very good, clean, USB ports.  I happen to use a MacBook Pro, which he tells me is very good, so I'm happy.  Also, FWIW, he tells me that most "Audiophile" USB cables do not appear to offer any measurable differences over standard cheap data cable,although there are a small number that do.
   
  My own experience - which was very much contrary to my expectations - was that a Nordost USB cable totally blew away a (relatively) high quality data cable, to the extent that I questioned whether the demonstrator was pulling the wool over my eyes.  But I bought the cable, and can easily replicate the results on my system at home.  Make of that what you will...


----------



## skeptic

Quote: 





talos said:


> I bought the cable, and can easily replicate the results on my system at home.  Make of that what you will...


 

 Any chance you'd be willing to run diffmaker and post the results?  It is freeware: http://www.libinst.com/Audio%20DiffMaker.htm


----------



## Rdr. Seraphim

So, what power is being supplied between a computer and an externally powered DAC--e.g. a MacPro and a Wyred 4 Sound DAC--via the USB cable? I can understand a USB port providing power to and external USB HD. However, it doesn't makes sense for an AC powered DAC to need power from the USB port. In that case, is the DC from the USB port unused?


----------



## kr0gg

as i've read DC line is needed for PC in order to recognize any device.
  so even though it might not be actually used while working it is necessary to have it connected.


----------



## Talos

Quote: 





> Any chance you'd be willing to run diffmaker and post the results?


 
   
  I'm not sure that would help here.  You are talking about the cable that connects my PC to my DAC.  I have no way to get the DAC's output back into the computer to digitize and compare.  I suppose I could run a cable with RCA's on one end and and a Mic jack on the other, from my DAC to the Mic input on my PC and digitize that.  The problem with that approach is that the sound quality would be seriously degraded by the analog input and D/A stages of the computer.  Those degradations would be (and say this in expectation, not, to be honest, having actually done it!) significantly greater than the differences induced by changing the USB cable.
   
  Or am I missing something?....


----------



## skeptic

It may be that the A/D circuit in your PC will mask the differences (assuming their are measurable differences), but supposedly diffmaker doesn't require super high end gear to work.  See the info on their page on the bottom right, under the heading "doesn't this process require ultra-high end recording equipment?"  
   
  If you have an RCA -> stereo mini cable on hand, to run from your dac to your PC in, it probably wouldn't take too terribly long to find out.  Please let us know if you have an opportunity to give it a try!


----------



## nick_charles

Quote: 





talos said:


> I'm not sure that would help here.  You are talking about the cable that connects my PC to my DAC.  I have no way to get the DAC's output back into the computer to digitize and compare.  I suppose I could run a cable with RCA's on one end and and a Mic jack on the other, from my DAC to the Mic input on my PC and digitize that.  The problem with that approach is that the sound quality would be seriously degraded by the analog input and D/A stages of the computer.  Those degradations would be (and say this in expectation, not, to be honest, having actually done it!) significantly greater than the differences induced by changing the USB cable.
> 
> Or am I missing something?....


 

 Quote:


skeptic said:


> It may be that the A/D circuit in your PC will mask the differences (assuming their are measurable differences), but supposedly diffmaker doesn't require super high end gear to work.  See the info on their page on the bottom right, under the heading "doesn't this process require ultra-high end recording equipment?"
> 
> If you have an RCA -> stereo mini cable on hand, to run from your dac to your PC in, it probably wouldn't take too terribly long to find out.  Please let us know if you have an opportunity to give it a try!


 


 If the differences are hidden by the A/D process then they are pretty small. For $30 you can pick up the Behringer UCA202 USB soundcard with ADC this will do a better job than a cheap integrated soundcard mic input and should resolve to about 15 bits or 1 part in about 32K (0.003%) so a difference that is smaller than this level (0.0003db) will be masked by quantization error but a "night and day" difference will not be masked.


----------



## 00940

I wouldn't have expected this thread to be still alive.
   
  Just to let you know, I've bought the January issue of Hifi News as the paper version was once again available on myhobbystore.co.uk last week. I'll post a summary of the article on usb cables and jitter (especially the measurements' results) when I get my hands on it... meaning end of August (I've got it shipped home but I'm abroad for the weeks to come).


----------



## Steve Eddy

Quote: 





prog rock man said:


> Prove that theory please.


 

 It's all just hand-waving.
   
  se


----------



## ac500

Here's an idea. Let's set aside the 40 page hand-waving debate over whether or not a certain USB protocol can lose data or add noise due to power line interference.
   
  Instead why don't we first address the claim that different USB cables modify the sounds; claims of it making it sounds "warmer" or "better sound stage" or "crisper highs" or whatever.
   
  To save you the trouble of reading through the endless pages of debate no doubt to follow, I'll jump the answer: It is theoretically _impossible_.
   
  Not just impossible as in, hey, that's like 0.000001% likely to happen. Impossible as in, if this is possible, then computers can spontaneously become self-aware, unicorns and pigs can fly, clouds are actually made of cotton candy, and magic is real.


----------



## LizardKing1

Quote: 





ac500 said:


> Not just impossible as in, hey, that's like 0.000001% likely to happen. Impossible as in, if this is possible, then computers can spontaneously become self-aware, unicorns and pigs can fly, clouds are actually made of cotton candy, and magic is real.


 

 And that is bad why? I dream of that evey night to feel like a little princess 0.0
   
  On a side note, a doubt has occurred to me: if a USB cable could change the data being transferred to a DAC, then when I put FLAC sound files from my desktop computer into my external Hard Drive using a USB-to-miniUSB, and then I put them in my laptop using that same cable from the Hard Drive, the files I put there might be different? So I'm not playing the same file?


----------



## upstateguy

Quote: 





ac500 said:


> Here's an idea. Let's set aside the 40 page hand-waving debate over whether or not a certain USB protocol can lose data or add noise due to power line interference.
> 
> Instead why don't we first address the claim that different USB cables modify the sounds; claims of it making it sounds "warmer" or "better sound stage" or "crisper highs" or whatever.
> 
> ...


 

 Oh please, just use your ears. 
   


  Quote: 





lizardking1 said:


> .....I dream of that evey night to feel like a little princess.....


 
   
  That's probably a little more than we need to know.


----------



## ac500

_> On a side note, a doubt has occurred to me: if a USB cable could change the data being transferred to a DAC, then when I put FLAC sound files from my desktop computer into my external Hard Drive using a USB-to-miniUSB, and then I put them in my laptop using that same cable from the Hard Drive, the files I put there might be different? So I'm not playing the same file?_
   
  Your USB cable cannot change the data rate. You DAC might downsample, but not the USB cable. I'd be willing to bet this has been said before on this thread, but unless the cable is faulty, it's going to work just fine. Even if it doesn't work fine, all you'll hear as a difference is skipping/clicking. Also, if you do hear skipping, it's more than likely that it has nothing to do with the cable and is instead your computer's USB controller having trouble (which could be due to any number of things).
   
  upstateguy: You can believe in unicorns and santa clause if you want.


----------



## upstateguy

Quote: 





ac500 said:


> upstateguy: You can believe in unicorns and santa clause if you want.


 

 You know I don't.


----------



## Head Injury

Quote: 





upstateguy said:


> You know I don't.


 

 Oh please, just use your eyes.
   
  I mean, you can find Santa in any major mall in the U.S. around Christmas.
   
  And how do you explain _this?_


----------



## DaBomb77766

I'm pretty sure this has been explained over and over and over again.  It is physically impossible for a USB cable to significantly (as in, audibly) change the sound.

 Also, data transfer works differently.  In this case, it really is a matter of "works or doesn't."  It is error-correcting and uses retransmission so if there are any errors the controller will request for that packet to be resent until it gets through perfectly.


----------



## LizardKing1

Quote: 





dabomb77766 said:


> Also, data transfer works differently.  In this case, it really is a matter of "works or doesn't."  It is error-correcting and uses retransmission so if there are any errors the controller will request for that packet to be resent until it gets through perfectly.


 

 I imagined something like that would happen. So I can never get a bit-different file in this kind of transfer, since any error will be corrected?
   
  Also I just read an article on the 21,000$ 3 meter Audioquest speaker cable. Would a snakeoil cables thread be a good idea? We could add the Cynosure from Locus cables, and the ALO LODs. What do you think?


----------



## DaBomb77766

Quote: 





lizardking1 said:


> I imagines something like that would happen. So I can never get a bit-different file in this kind of transfer, since any error will be corrected?
> 
> Also I just read an article on the 21,000$ 3 meter Audioquest speaker cable. Would a snakeoil cables thread be a good idea? We could add the Cynosure from Locus cables, and the ALO LODs. What do you think?


 


  Data corruption while transferring data with USB is very rare...and if it does actually happen (not sure if it's even really possible unless you accidentally unplug the cable while it's transferring or if the computer crashes), chances are the file won't even open/won't work at all.  But as far as I know, that never happens...at any rate, it's not something anyone should worry about.
   
  There already are "snakeoil cable threads," sort of.  The "audiophile myths" thread is one of them, and this is kind of another.
   
  To me, Locus is one of the worst...if you look at how much their flagship USB cable is then look at their "trial policy," it's pretty ridiculous. (something like a 20% "restocking fee" for a $2500 cable, shipping and handling not included...)


----------



## LizardKing1

I'm reading their description on the Cynosure and it's amazing. Literally like a fairytale.
   
  Anyway, I'll just leave this here:
  http://www.noiseaddicts.com/2008/11/most-expensive-speaker-cable-world-audioquest-audiophile/


----------



## drez

I would place locus [pocus?] design in the same bag with LessLoss audio.  The way they market their products is appalling and dumb, as is the physical width of their flagship cable.
   
  "hear the difference" doesn't cut it -  there are too many frailties to casual perception to rely upon it.  One can either measure electrical performance, then prove that the results can be heard, or do a direct ABX or equivalent. 
   
  With USB cables it really is the measurements that count, and the changes a USB cable make can only be to RF noise and signal Jitter.  There is no mysterious magic going on to warrant such a product development approach.  
   
  At the very least some oscilloscope measurements with real world connectors would be appropriate, but it would seem as price increases, accountability decreases and snake oil factor increases.


----------



## chinesekiwi

Lossless however has the advantage of archiving and transcoding without extra loss in data quality. With hard drive storage so cheap these days, lossless is a more than legitimate option to backup your audio data.
   
  The protocol USB is noisy...however than due to the USB controller and not the cable itself. That and it's not likely at all audible.


----------



## LizardKing1

Quote: 





chinesekiwi said:


> Lossless however has the advantage of archiving and transcoding without extra loss in data quality. With hard drive storage so cheap these days, lossless is a more than legitimate option to backup your audio data.


 
   
  I think he was talking about Lessloss, another shady cable company.
  http://www.lessloss.com/tunnelbridge-distortionless-interconnect-system-p-204.html
  They have a machine that increases the quality of your interconnects! I might be wrong, but I thought adding more stuff to the signal's plath was bad.
   
  Oh and what consensus did this thread reach on power cables? I understand that the fact thatyou have hundreds of meters of cable in your walls conducting the power is going to count more than the high quality stuff that you use for those 2 meters, but a friend of mine once told me his DVD player needed a good power cable to work, and the normal cable wasn't good enough... I know I could go back and read everything, but come on...


----------



## Prog Rock Man

Quote: 





drez said:


> I would place locus [pocus?] design in the same bag with LessLoss audio.  The way they market their products is appalling and dumb, as is the physical width of their flagship cable.
> 
> "hear the difference" doesn't cut it -  there are too many frailties to casual perception to rely upon it.  One can either measure electrical performance, then prove that the results can be heard, or do a direct ABX or equivalent.
> 
> ...


 



 That is what does it for me and cables, all cables. No maker can prove a link between the way they make a cable and how it can sound different from other cables. Any difference is not in the cable.


----------



## Willakan

LessLoss' credibility is further damaged by the fact they sell the "LessLoss Blackbody," (a magical quantum McGuffin) which only the most devoted audiophile would believe actually works. It received a good review from 6moons, but then again, the reviewer also seemed to be labouring under the delusion that he could feel wireless networks and that they suppressed his mental faculties through means unknown.


----------



## travisg

My Cynosure USB cable will be here this week so I will see just how good it is.


----------



## Willakan

Are you going to see how good it is with a blind test, or are you merely going to plug it in and decide whether it sounds better?


----------



## ac500

It seems as absurdly easy a double blind test is to do, nobody who buys into the snakeoil cable market actually tries them. Well, in fact, I suspect many do try it, but find that they can't distinguish a difference when they don't know which cable they're listening to. Then they simply don't post anything, or say something like: "Well just use your ears!" [_Ironically enough, a double blind test isolates exactly that - your ears]_ "All that really matters anyway is whether you get enjoyment out of it. Everything else doesn't matter!" _[Nervous laughter as the brain subconsciously suppresses knowing that $1000 was paid on something absolutely worthless.]_


----------



## Head Injury

Quote: 





ac500 said:


> It seems as absurdly easy a double blind test is to do, nobody who buys into the snakeoil cable market actually tries them. Well, in fact, I suspect many do try it, but find that they can't distinguish a difference when they don't know which cable they're listening to. Then they simply don't post anything, or say something like: "Well just use your ears!" [_Ironically enough, a double blind test isolates exactly that - your ears]_ "All that really matters anyway is whether you get enjoyment out of it. Everything else doesn't matter!" _[Nervous laughter as the brain subconsciously suppresses knowing that $1000 was paid on something absolutely worthless.]_


 

 What's even worse, the snakeoil cable companies don't do it either. You'd think it would be a great way to prove superiority over competitors. Even small DBTs with a couple people, which wouldn't be very significant scientifically, would be more than enough to impress consumers and make great review fodder to boot.
   
  But differences wouldn't show up. And the target market, subjective as it is, doesn't care much anyway.


----------



## Talos

Quote: 





> I'm pretty sure this has been explained over and over and over again.  It is physically impossible for a USB cable to significantly (as in, audibly) change the sound.


 
   
  Just how old are you?  Do you remember "_Pure Perfect Sound, Forever_".  Do you know/remember what the first CD players sounded like back in the '80's before they discovered jitter?  Bits-is-bits-is-bits, they told us.  So, now we have discovered jitter, we understand it, and we buy into it, and we accept that bits-wasn't-bits-wasn't bits.  But today, so you tell us, a USB cable can't _POSSIBLY_ affect the sound quality, because we _KNOW _that the signal is re-clocked at the DAC, so there _CAN'T_ be any jitter, so it _CAN'T POSSIBLY_ affect the sound.  And, moreover, there is _NO POSSIBILITY WHATSOEVER_ that there may be other effects that we haven't got round to reliably quantifying/measuring yet.
   
  And I'm so dumb, that I'm just hearing things that I want to hear?  Puh-lease!
   
  So tell me, if a signal is playing at (for example) 24/192, just how small must the jitter be in order for it to be incapable of inducing significant artifacts (_i.e._ artefacts which would cause the digital data stream to be different if it were re-sampled) into a theoretically perfect DAC's output?  And how would you set about measuring that?...  Now, I'm no expert, but I think I can do that calculation.  Why don't you give it a go yourself, and tell me what you come up with.  (Hey, I'm not trying to put you down here - I'm being serious).


----------



## ac500

Placebo effect has nothing to do with being dumb. You could be the most brilliant person in the world and still "suffer" from the effect.
   
  I'll admit I am not an electrical engineer (but a computer engineer), so I can't say very specifically how DACs are designed internally. However I do know that there is literally no way a digital audio signal itself can be modified in sound due to the digital cable. At most, you'll have data loss and skipping of samples, which could cause stuttering or skipping. To modify the sound, the sound waveform itself would need to change in a very specific way. Again, skipping samples would cause skipping sounds, not a "warmer sound" or "better soundstage". It's just impossible.
   
  Do modern DACs actually run directly off the USB data feed without any buffering? Do they not have their own local clock signal? If they run off a USB clock and/or don't buffer the data feed, that sounds _incredibly stupid_ to me. That's not a digital problem, it's a flaw with the DAC circuit implementation if clock jitter is permitted to be introduced to the analog output. Still, this won't change the sound signature. Even in this case a better cable won't give you boosted bass, or "better soundstage" or whatever; at most, a jittered clock to the DAC could definitely make it sound distorted and "rough" sound, but again, _this is a flaw with your DAC circuit implementation. _And again, even in this case, there's no way it can give you a "bass boost" or "louder treble" etc.
   
  This was my only point to begin with. People who imagine a bass or treble boost or totally different sound signature coloration must be imagining things, because this is simply not possible. Jitter and noise coming out of the DAC are of course to be expected, but that's a DAC issue. The cable shouldn't effect this, if the DAC circuit is properly designed.


----------



## DaBomb77766

Quote: 





talos said:


> Just how old are you?  Do you remember "_Pure Perfect Sound, Forever_".  Do you know/remember what the first CD players sounded like back in the '80's before they discovered jitter?  Bits-is-bits-is-bits, they told us.  So, now we have discovered jitter, we understand it, and we buy into it, and we accept that bits-wasn't-bits-wasn't bits.  But today, so you tell us, a USB cable can't _POSSIBLY_ affect the sound quality, because we _KNOW _that the signal is re-clocked at the DAC, so there _CAN'T_ be any jitter, so it _CAN'T POSSIBLY_ affect the sound.  And, moreover, there is _NO POSSIBILITY WHATSOEVER_ that there may be other effects that we haven't got round to reliably quantifying/measuring yet.
> 
> And I'm so dumb, that I'm just hearing things that I want to hear?  Puh-lease!
> 
> So tell me, if a signal is playing at (for example) 24/192, just how small must the jitter be in order for it to be incapable of inducing significant artifacts (_i.e._ artefacts which would cause the digital data stream to be different if it were re-sampled) into a theoretically perfect DAC's output?  And how would you set about measuring that?...  Now, I'm no expert, but I think I can do that calculation.  Why don't you give it a go yourself, and tell me what you come up with.  (Hey, I'm not trying to put you down here - I'm being serious).


 


  I'm not talking about just jitter here, I'm talking about the cables.  Any jitter that there may be won't be introduced by the cables but by the USB controllers, which actually can introduce a significant amount of jitter to the bitstream.  However, having a better cable simply will not help with this.  It may hypothetically reduce the amount of damage being done to the stream as much as possible, but if you have jitter, it's always gonna be there whether your cable is $2000 or not.  The amount of jitter a competently designed USB cable will actually introduce into the bitstream is utterly insignificant at the frequencies audio operates at.  I mean, these (USB 2.0) are designed to transmit data at around 480Mbits/s, if you had bits dropping and getting skewed everywhere along the line, you'd barely be able to transfer anything, let alone transfer data at that speed without some serious slowdown.
   
  Rather, the real issues involved here are that of the controller and the clock, not the cable.  And I highly doubt that the guys at, say, Locus have spent as much time and energy (read: millions of dollars and thousands of man hours), nor have as much experience in designing a cable to work with the USB protocol.  They clearly just feel that their experience in making analog cables out of pure silver will translate directly into making digital cables.  They probably don't even make measurements, because there really aren't any for them to take...they'd just show that it's not helping.  Not to mention the tools they would need to measure such things would be extremely expensive.
   
  At any rate, show me some solid measurements that show that an audiophile USB cable will measure differently (doesn't even have to be audible) from any run-of-the-mill USB cable that comes bundled with a camera or something then we'll talk.  And please don't say that there's "something we haven't discovered yet," if this "something" was really so much of a problem, then it would have plagued high-speed data transfer far more than the relatively low-stress job of transmitting audio (10Gbps is a lot more than what's transmitted with audio.  And as far as timing problems go, the wiring inside of a computer must be extremely, extremely precise since at the speeds at which the processor operates, pretty much any deviation of the signal will cause bad things to happen).


----------



## DaBomb77766

Quote: 





ac500 said:


> Placebo effect has nothing to do with being dumb. You could be the most brilliant person in the world and still "suffer" from the effect.
> 
> I'll admit I am not an electrical engineer (but a computer engineer), so I can't say very specifically how DACs are designed internally. However I do know that there is literally no way a digital audio signal itself can be modified in sound due to the digital cable. At most, you'll have data loss and skipping of samples, which could cause stuttering or skipping. To modify the sound, the sound waveform itself would need to change in a very specific way. Again, skipping samples would cause skipping sounds, not a "warmer sound" or "better soundstage". It's just impossible.
> 
> ...


 


  Actually, as far as I know, most DACs do run without any internal buffering...all of the buffering is done on the host-side, from what I understand.  Not really sure why this is though...I think it's something to do with how the USB protocol works.


----------



## ac500

That's horrible. There should be no reason a high quality DAC box can't have its own buffer and clock.
   
  Even in the case where you're relying on an external clock, it's still not gonna change the sound signature like boosting bass or whatever. That was my only point here.


----------



## leeperry

ac500 said:


> That's horrible. There should be no reason a high quality DAC box can't have its own buffer and clock.
> 
> Even in the case where you're relying on an external clock, it's still not gonna change the sound signature like boosting bass or treble or whatever. That was my only point here.


 

 based on zero real world experiment I presume? making your opinion mostly a wild guess?


----------



## ac500

The big wild guess is that jitter will cause audible distortion at all, because all I've ever encountered was skipping due to the USB controller. I don't even know what clock rates we're talking about here, or the specifics of how DACs work, so it may not even be an issue within the spectrum of human hearing _at all_, for all I know.
   
  The non-guess (fact) is that to have boosted bass, you need to modify the digital signal in a very specific, low-frequency way. Jitter at most will distort the analog output at a high-frequency granularity. This cannot change the amplitude of sound across the frequency spectrum like believers seem to say.
   
  Also, keep in mind this is the science forum. You have two options to assert a claim:
   
  1) Do a double-blind test. Sorry, "use you ears and eyes" doesn't work here. Only "use your ears without eyes" is proof, and it must be statistically significant.
   
  2) Show scientifically why something is or is not possible, under a given context.


----------



## leeperry

ac500 said:


> The big wild guess is that jitter will cause audible distortion


 
   
  The jitter matter has been beaten up to death.
   
  I haven't claimed anything, I'm mostly asking what experiments you've conducted in order to reach those very interesting conclusions of yours...and it would appear that you're mostly guessing how a USB audio controller and a DAC chip work together, and haven't done any homework whatsoever. We all know that USB is just a bunch of 0's and 1's, don't we.


----------



## DaBomb77766

Quote: 





leeperry said:


> The jitter matter has been beaten up to death.
> 
> I haven't claimed anything, I'm mostly asking what experiments you've conducted in order to reach those very interesting conclusions of yours...and it would appear that you're mostly guessing how a USB audio controller and a DAC chip work together, and haven't done any homework whatsoever. We all know that USB is just a bunch of 0's and 1's, don't we.


 

 ...USB is just a bunch of 1s and 0s?  There's no in-between here...


----------



## ac500

_> The jitter matter has been beaten up to death._
   
  Exactly. Which is why I'm trying to talk about the discretely provable matter: Whether a digital signal across a cable can go in one end as waveform A, and emerge on the other as the completely differently characterized waveform B with boosted bass. Sorry, this doesn't happen, and it's not hard to prove formally, even taking signal error and jitter into account.
  
_> I haven't claimed anything, I'm mostly asking what experiments you've made in order to make those statements..._
   
  You don't understand. A digital waveform is numeric data which either arrives intact, or with errors or missing data. In both cases (errors, and missing data), it's easy to prove mathematically that this will NOT produce, for example, a bass boost, under _any_ circumstances (barring a probability which likely rivals the chances of spontaneous formation of living cells from raw materials).
   
  Again, it's not particularly difficult (maybe tedious) to prove mathematically that errors introduced into a digital stream won't magically cause the bass to be boosted. It just doesn't work that way, period! To say otherwise is like saying two times two is not four.
   
  If you really want, I could write out a _formal proof_ that random errors and skipped samples and even jitter, no matter how severely introduced into a digital stream, will not produce a bass boost effect. But then again, it will make no sense unless you've taken at least undergrad (college) level discrete mathematics, probability theory, and calculus. Those of you who do understand what I'm talking about here fully will know how to prove it yourself anyway, and most likely are on the non-believer side to begin with.


----------



## upstateguy

Hey guys, what about reflections in digital cables?


----------



## Mad Max

Quote: 





ac500 said:


> _> The jitter matter has been beaten up to death._
> 
> Exactly. Which is why I'm trying to talk about the discretely provable matter: Whether a digital signal across a cable can go in one end as waveform A, and emerge on the other as the completely differently characterized waveform B with boosted bass. Sorry, this doesn't happen, and it's not hard to prove formally, even taking signal error and jitter into account.
> 
> ...


 
   
  Isn't jitter errors in the timing of the information in the signal?  =\


----------



## ac500

As I understand it, yes. If you're lazy and don't implement a data buffer + local clock for your DAC, then the jitter would be applied directly to the DAC output, and therefore the analog waveform output could contain this jitter. If the clock is considerably higher than the range of human hearing though, jitter should not be an issue, but again I'm not an expert here.
   
  Anyway at most, jitter might cause high-frequency (sub-clock timing) distortion to the output waveform. Never anything that would even come close to effecting the bass, for example.


----------



## Talos

Quote: 





> Any jitter that there may be won't be introduced by the cables but by the USB controllers


 
  Actually, I am trying to get you to justify that statement.  Because it simply isn't true.  Let me refer you to the Wikipedia page (because it is convenient, not because it is an absolute reference) here.  In the paragraph "Sampling jitter" it states "_less than a nanosecond of jitter can reduce the effective bit resolution of a converter with a Nyquist frequency of 22 kHz to 14 bits_"  I think it means 16 bits, not 14, as it is referring to CD playback.  Where does <1ns come from?  Well, when you convert a digital signal to analog, the thing to bear in mind is this:  _*The right signal at the wrong time is the wrong signal.*_  So, if a digital data stream contains 16-bit data, this means that the data is specified with a resolution of one part in 65,536.  It is straightforward to appreciate that this means that the sample has to be converted from the digital domain to the analog domain at a point in time which is accurate to within 1/65,536th of the sampling interval.  The sample frequency is 44.1kHz, so the sampling interval is 22.7 microseconds.  Therefore, if the DAC timing signals are wrong to within 1/65,536th of 22.7 microseconds (346 picoseconds), then the analog signal will be _*wrong*_.  This is what we mean by jitter.  If the digital data stream is to be systematically accurate to within 346ps, and we assume that the USB controller at the computer is perfect, and presents a source signal with no jitter, this implies that the bandwidth of the signal delivery system - the USB cable - needs to be close to 1GHz.  That is non-trivial.  I think it is not unreasonable to postulate that different USB cables _can _have different transmission characteristics in the GHz frequency range, and thereby _can _have - in principle - an audible effect on red book music.
   
  Now lets move on to something like 24/192.  If we apply the same rationale, then the jitter requirement becomes 310 femtoseconds.  A femtosecond is a millionth of a billionth of a second.  And the bandwidth required to systematically guarantee jitter-free transmission is a _thousand _GHz.  USB cables do _NOT _transmit those frequencies.  Do you still insist that a USB cable _CANNOT_ _POSSIBLY _impact the sound of the resultant analog signal?  Yes or no?


----------



## digger945

Quote: 





ac500 said:


> Anyway at most, jitter might cause high-frequency (sub-clock timing) distortion to the output waveform. Never anything that would even come close to effecting the bass, for example.


 

 ... and yet when most folks try out an async transport or dac you almost always see that the first remark is something like "better defined bass." This would include myself. In addition to turning the volume down.
  Why is that?


----------



## Mad Max

Quote: 





ac500 said:


> As I understand it, yes. If you're lazy and don't implement a data buffer + local clock for your DAC, then the jitter would be applied directly to the DAC output, and therefore the analog waveform output could contain this jitter. If the clock is considerably higher than the range of human hearing though, jitter should not be an issue, but again I'm not an expert here.
> 
> Anyway at most, jitter might cause high-frequency (sub-clock timing) distortion to the output waveform. Never anything that would even come close to effecting the bass, for example.


 

 Probably why the TAS1020B has its own data buffer built-in.  The human-hearing range has absolutely nothing to do with the clock.


----------



## Head Injury

Quote: 





digger945 said:


> ... and yet when most folks try out an async transport or dac you almost always see that the first remark is something like "better defined bass." This would include myself. In addition to turning the volume down.
> Why is that?


 

Take your pick.
   
  A few of my favorites for this situation are bandwagon effect, expectation bias, hindsight bias, and suggestibility.
   
  There is absolutely nothing wrong with being fooled by any of these.


----------



## DaBomb77766

Quote: 





talos said:


> Actually, I am trying to get you to justify that statement.  Because it simply isn't true.  Let me refer you to the Wikipedia page (because it is convenient, not because it is an absolute reference) here.  In the paragraph "Sampling jitter" it states "_less than a nanosecond of jitter can reduce the effective bit resolution of a converter with a Nyquist frequency of 22 kHz to 14 bits_"  I think it means 16 bits, not 14, as it is referring to CD playback.  Where does <1ns come from?  Well, when you convert a digital signal to analog, the thing to bear in mind is this:  _*The right signal at the wrong time is the wrong signal.*_  So, if a digital data stream contains 16-bit data, this means that the data is specified with a resolution of one part in 65,536.  It is straightforward to appreciate that this means that the sample has to be converted from the digital domain to the analog domain at a point in time which is accurate to within 1/65,536th of the sampling interval.  The sample frequency is 44.1kHz, so the sampling interval is 22.7 microseconds.  Therefore, if the DAC timing signals are wrong to within 1/65,536th of 22.7 microseconds (346 picoseconds), then the analog signal will be _*wrong*_.  This is what we mean by jitter.  If the digital data stream is to be systematically accurate to within 346ps, and we assume that the USB controller at the computer is perfect, and presents a source signal with no jitter, this implies that the bandwidth of the signal delivery system - the USB cable - needs to be close to 1GHz.  That is non-trivial.  I think it is not unreasonable to postulate that different USB cables _can _have different transmission characteristics in the GHz frequency range, and thereby _can _have - in principle - an audible effect on red book music.
> 
> Now lets move on to something like 24/192.  If we apply the same rationale, then the jitter requirement becomes 310 femtoseconds.  A femtosecond is a millionth of a billionth of a second.  And the bandwidth required to systematically guarantee jitter-free transmission is a _thousand _GHz.  USB cables do _NOT _transmit those frequencies.  Do you still insist that a USB cable _CANNOT_ _POSSIBLY _impact the sound of the resultant analog signal?  Yes or no?


 


  I will not insist that a USB cable cannot possible impact the analog signal - however, I will insist that, until I see actual measurements, the differences will not be audible, and maybe not even (easily) measurable.  Not talking about jitter alone here - just the jitter added by a crappy (i.e. a normal, non-audiophile, apparently) USB cable.
   
  Anyway, you can give all of the theoretical math you want, but things like that rarely translate into real-life so smoothly when we're dealing with the physical world...and you do have to realize that if you're using a 24/192 signal, even if you cut half of that signal out, most people aren't gonna be able to tell the difference since that's nearing the edge of inaudibility.  And if the odd bit here and there are corrupted, sure, the analog signal will be changed...but it will be practically impossible to measure the change.


  Quote: 





digger945 said:


> ... and yet when most folks try out an async transport or dac you almost always see that the first remark is something like "better defined bass." This would include myself. In addition to turning the volume down.
> Why is that?


 

  
  ...and we're talking about different people using different hardware here?  If they have to turn the volume down it means that the devices aren't volume matched and therefore the listening test is irrelevant.  If you're using two different DACs, one asynchronous and one standard run-of-the-mill one...well, they're different pieces of hardware.
   
  I cannot, however, really comment on this unless I know exactly what you're talking about.  Context has meaning, you know.


----------



## digger945

Quote: 





head injury said:


> Take your pick.
> 
> A few of my favorites for this situation are bandwagon effect, expectation bias, hindsight bias, and suggestibility.
> 
> There is absolutely nothing wrong with being fooled by any of these.


 


  Heh. I don't want to believe. I want things to be very simple and all digital stuff to be the same, no matter what. Yet there are noticeable differences. I'm talking about listening to things for weeks or months, not just A/B A/B testing. It takes my ears and brain weeks sometimes to acclimate to anything different.
   
  I believe noone. I listen without thinking or analyzing.


----------



## digger945

Quote: 





dabomb77766 said:


> ...and we're talking about different people using different hardware here?  If they have to turn the volume down it means that the devices aren't volume matched and therefore the listening test is irrelevant.  If you're using two different DACs, one asynchronous and one standard run-of-the-mill one...well, they're different pieces of hardware.
> 
> I cannot, however, really comment on this unless I know exactly what you're talking about.  Context has meaning, you know.


 

 Every single part of the system is the same right down to the song. The only change is the USB to SPDIF converter. This past June makes one year comparing.


----------



## chinesekiwi

*From a certain blog people don't like:*
  ______________________________________________________________________________________________________________________
   
*USB POWER IS NOISY:* Many of the reasonably priced USB DACs are USB powered. The USB power bus suffers from lots of noise. The very wires that deliver the DC power are right next to high speed noisy data signals bundled into the same cable. _It's also power shared with other USB devices on the system which may even include things like RF Bluetooth or WiFi "dongles" which add RF noise._

 You may find reviews that talk about a USB DAC being noisy on one PC and quiet on another. Or even noisy only at certain times when the PC is doing certain things. This isn't uncommon as the amount of noise a PC generates can vary a lot. And any RF devices--like WiFi or Bluetooth--send their signals intermittently so the may generate what seems like random noise.

 A good USB DAC may have it's own power supply that attempts to filter out or isolate the DAC from the noisy USB power, but this is hard to do cheaply. And it's hard to do well in a physically small product where the noisy power circuitry is physically only a few millimeters away from the sensitive audio circuitry. But it _can_ be done.
  ________________________________________________________________________________________________________________________
   
_i.e. via the USB controller, not the cable._
   
  y'know all electrical cables follow set standards for a reason.


----------



## Head Injury

Quote: 





digger945 said:


> Heh. I don't want to believe. I want things to be very simple and all digital stuff to be the same, no matter what. Yet there are noticeable differences. I'm talking about listening to things for weeks or months, not just A/B A/B testing. It takes my ears and brain weeks sometimes to acclimate to anything different.
> 
> I believe noone. I listen without thinking or analyzing.


 

 See, now I'm picking up on some "bias blind spot".
   
  Just because you don't want to believe someone, or think you don't believe someone, doesn't mean you don't believe someone.
   
  That sentence is a beautiful mess of negatives.


----------



## chinesekiwi

I think digger945 was testing your sarcasm radar. It failed.


----------



## Head Injury

Quote: 





chinesekiwi said:


> I think digger945 was testing your sarcasm radar. It failed.


 

 I've heard the "I didn't want to like it, but I did!" argument against bias far too often to think of his as sarcasm.


----------



## digger945

Quote: 





chinesekiwi said:


> I think digger945 was testing your sarcasm radar. It failed.


 


  Thank you.


----------



## DaBomb77766

Quote: 





digger945 said:


> Every single part of the system is the same right down to the song. The only change is the USB to SPDIF converter. This past June makes one year comparing.


 


  That's still not very specific.  Are we talking hypothetically here or actual examples of what people are experiencing?

 Whatever the case, my explanation would simply be that for some reason the amp outputs one of them at a higher volume than the other one.  This can make people feel that the "bass is fuller" and basically feel like everything sounds better.


----------



## digger945

Quote: 





dabomb77766 said:


> That's still not very specific.  Are we talking hypothetically here or actual examples of what people are experiencing?
> 
> Whatever the case, my explanation would simply be that for some reason the amp outputs one of them at a higher volume than the other one.  This can make people feel that the "bass is fuller" and basically feel like everything sounds better.


 


   
  My system. My amp. My usb to spdif transports. Stuff I have listened to for years now.
   
  Balanced Dynahi.
  0404usb. Gamma 2. Halide Bridge. 
  Balanced Denon 2k. Grado 225. Senn HD250. Fostex T50RP.
   
    I guess I thought that somehow the act of controlling the usb controller from an external source might have some bearing on the whole conversation.


----------



## Prog Rock Man

The evidence is certainly waited in favour of the argument that USB cables do not influence sound quality. There is only speculation as to how a USB cable could affect sound quality, which in a science forum is not good enough.


----------



## drez

Well you can probe that a cable can affect the square waveform of a digital signal, and that this influences jitter, and that jitter can introduce distortion.
   
  00940 appears to have a good understanding of the metrics in question, so I will refer to his previous post which will do much better than anything I can cobble up:
   
   
   
  Quote: 





> Originally Posted by *00940*
> 
> 
> 
> ...


----------



## ac500

Very good quote. One thing to note is that all the things he mention are either skipping, or distortion / high frequency noise. Even at a stretch -- assuming that USB cable can reduce distortion, there's still no possible way it can effect the actual sound signature -- like boosting bass, for example.


----------



## Talos

Quote: 





> I will not insist that a USB cable cannot possible impact the analog signal ...


 
  Good!  Progress!  
	

	
	
		
		

		
			




   
  Quote: 





> ... but it will be practically impossible to measure the change


 
  Yes, I _almost _agree with that.  When talking about jitter, it is not actually so hard to measure it, and quantify it.  What does represent a challenge, though, is to perform a rigorous analysis of the impact of jitter on a resultant analog waveform, and to thereby come up with a definite objective of something to look for and measure that is quantitatively representative of something that could be audible.  There are measurements you can make on an analog waveform, and things that you _can _look for in those measurements that _can _be shown to be artifacts of jitter, but I don't think anybody would claim to be able to tell you what these things should actually sound like.
   
  DaBomb, can I solicit your views on audibility vs measurability?  Would you, for example, state that because a thing cannot be measured therefore it cannot be audible?  What about the other way around.  Would you state that anything that is audible can _de facto_ be measured?  For example, I think we all would agree that some systems can project a much-prized "holographic soundstage".  I know of no way of measuring that property.  And I don't mean that we can't measure things that tend to correlate well with sound imaging.  Just that we can't actually measure a system's _imaging _in any quantitative way.  I am wondering, DaBomb, would you agree with that?


----------



## DaBomb77766

Quote: 





talos said:


> DaBomb, can I solicit your views on audibility vs measurability?  Would you, for example, state that because a thing cannot be measured therefore it cannot be audible?  What about the other way around.  Would you state that anything that is audible can _de facto_ be measured?  For example, I think we all would agree that some systems can project a much-prized "holographic soundstage".  I know of no way of measuring that property.  And I don't mean that we can't measure things that tend to correlate well with sound imaging.  Just that we can't actually measure a system's _imaging _in any quantitative way.  I am wondering, DaBomb, would you agree with that?


 

  
  I would agree that we cannot measure a system's "imaging" in any real sense.  However, "imaging" is a very abstract term...and many people don't seem to understand what it means.  It's more to do with how your brain processes the information it receives.
   
  Still, I do agree that somethings like that cannot be expressed in data...however, I don't think the case is that it simply cannot be measured.  It's just that we don't know how to interpret the data correctly.  I'm sure all of the data is there - everything we can hear, the microphones can hear better.  However, what we don't understand is exactly how the brain processes this information, and thus, we don't know what part of the signal equates to "holographic imaging."  Maybe some day when we have more accurate psychoacoustic models that are derived from actual studies of how the brain processes audio information this will change...but we just don't know yet.
   
  As such, my view is, whether we understand what the change is or not, our current equipment can measure everything that a cable change could possible affect.  Maybe the tiny little changes that we dismiss as "inaudible" actually make a difference - I don't know.  But the point is, no data whatsoever points towards a USB cable changing the signal in any way whatsoever.  If it does then maybe there will be something to this myth.  Until then, I simply have no choice but to dismiss it as your typical audiophile mumbo-jumbo.


----------



## ac500

Whenever a discussion degenerates to the point of discussing the "immeasurable" or un-interpretable data, it becomes a useless debate. Unless, you do a double blind test.
   
  As for double blind tests: If USB cables had an audible difference, no matter how subtle, a trained expert "believer" whose listened to both extensively should be able to distinguish them blindly. And that's all I have to say for the double blind area.
   
  Beyond that, lets try to stick to the scientific observations of USB cable: There is a remote possibility that a bad cable would introduce jitter (= high frequency distortion) into a retardedly designed (unbuffered) DAC, skipping, and maybe background white noise.
   
  Ok, giving the "believers" the benefit of the doubt, I ask:* Do you still assert that USB cables can give you a different sound signature? Like boosting bass, for example?*
   
  I think if we want this discussion to be productive we _need_ to focus on the issue I highlight above first. Noise will always be a tiny little unmeasurable possibility, and jitter is possible with an unbuffered DAC. However if your DAC does run off a buffered source, and with its own local clock, then USB-dependent jitter simply should not be happening.


----------



## leeperry

> Originally Posted by *ac500* /img/forum/go_quote.gif
> 
> giving the "believers" the benefit of the doubt, I ask: Do you still assert that USB cables can give you a different sound signature? Like boosting bass, for example?


 

 of course not, more like a clearer sound/soundstage...as in less jitter/THD.


----------



## ac500

Ok, so it's mostly just a debate regarding jitter.
   
  In this case, I wonder if anyone with a buffered DAC would comment. A DAC running off a buffered data source and an internal clock should have no USB-dependent jitter whatsoever.


----------



## Head Injury

Quote: 





ac500 said:


> Ok, so it's mostly just a debate regarding jitter.
> 
> In this case, I wonder if anyone with a buffered DAC would comment. A DAC running off a buffered data source and an internal clock should have no USB-dependent jitter whatsoever.


 

 I don't know how the Benchmark DAC1 handles USB jitter specifically, but a graph in the manual shows that its jitter isn't affected by cables (probably coaxial) 1000 feet in length.
   
  When it gets here I could do some subjective sighted comparisons between the uDAC and the DAC1, but that would hardly be a fair comparison in other aspects like general THD+N and crosstalk.  I won't be able to separate all of that out from the jitter. I don't exactly know what jitter is supposed to sound like.


----------



## 00940

The Benchmark DAC1 sends all incoming digital signals (coax or usb) through an AD1896, an ASRC. This ASRC's output is clocked by a local low noise clock. As such, any jitter in the incoming signal is heavily reduced by the ASRC's filters and the little that cannot be suppressed transformed into noise. The reduction is good enough for this amount of noise to be very low, for any reasonable incoming amount of jitter.
   
  As a matter of fact, according to this Stereophile's article quoting the designer of the DAC1 ( http://www.stereophile.com/digitalprocessors/108bench/ ), the implementation chosen by Benchmark for the TAS1020b (the chip converting USB signals to I2S) leads to "significant" amount of jitter. This jitter is however nicely reduced by the ASRC.
   
  The only way I can imagine for an USB cable to significantly alter the jitter of the clock fed to the DAC1's AD1853 would be through noise coupling... the local oscillator jitter figures are indeed function of the quality of the power supply it's being fed. Good PCB layout practices would make this concern go away and we can safely assume that those practices were applied.


----------



## upstateguy

Quote: 





prog rock man said:


> The evidence is certainly waited in favour of the argument that USB cables do not influence sound quality. There is only speculation as to how a USB cable could affect sound quality, which in a science forum is not good enough.


 


  Hi Ian
   
  There was a long thread in diyaudio by Joseph K, complete with measurements and scope pics, about the Hiface and the use of attenuators to reduce the reflections in the coax cable (which affected the sound).  One would think that since a digital signal is a digital signal, there would also be reflections in a usb cable.
   
  Eric
   
  Edit:  Even Jocko Homo from diyHIFI.org posted in one of the jkeny threads about the use of attenuators to clean up the digital signal in coaxial cables.


----------



## Willakan

Reflections exist, but where is the evidence of audibility?


----------



## DaBomb77766

Quote: 





willakan said:


> Reflections exist, but where is the evidence of audibility?


 


  Fortunately for everyone involved except the boutique cable manufacturers, nowhere.  There do need to be more professionally-done measurements done on this though...I wonder if nwavguy would be up to the job.


----------



## Prog Rock Man

Quote: 





leeperry said:


> of course not, more like a clearer sound/soundstage...as in less jitter/THD.


 

 Can you prove that?


----------



## svyr

maaan, I couldn't resist, so I emailed usb.org


----------



## leeperry

prog rock man said:


> Can you prove that?


 

 Once you will have found and bought me the equipment to measure USB jitter, shure thang buddy!


----------



## svyr

leeperry said:


> Once you will have found and bought me the equipment to measure USB jitter, shure thang buddy!




don't they use THD+N and IMD as proxies for that?


----------



## upstateguy

Quote: 





willakan said:


> Reflections exist, but where is the evidence of audibility?


 

 Check out the diyaudio and diyHIFI threads for the scope shots.  The oscilloscope shots show that the hash is in the audio spectrum and that attenuators help clean it up.  I'm not an engineer, but I think they called it "padding" the line.
   
  Check it out.


----------



## nick_charles

Quote: 





upstateguy said:


> Check out the diyaudio and diyHIFI threads for the scope shots.  The oscilloscope shots show that the hash is in the audio spectrum and that attenuators help clean it up.  I'm not an engineer, but I think they called it "padding" the line.
> 
> Check it out.


 


 Fine, but but still does not mean it is audible, for that you need controlled listening tests


----------



## nick_charles

Bob Adams (Analog devices)   the youngest ever AES Fellow did a very good paper on jitter you can find a version of it in the back issues of The Audio Critic,
   
http://www.theaudiocritic.com/back_issues/The_Audio_Critic_21_r.pdf
   
  he concluded that measuring jitter at the clock was almost always actually unnecessary as you can see it downstream in THD and IMD and if you read stereophile's measurements you will see that no device that has really bad jitter ever has good THD or IMD
  Quote: 





svyr said:


> don't they use THD+N and IMD as proxies for that?


----------



## leeperry

You can read coax cables reviews that claim different jitter measurements depending on which direction the cable was connected...why not USB again? Neither of those 2 protocols use ECC.


----------



## Willakan

Ironic, you finally get them to use measurements in reviews and they promptly go too far the other way and decide that if they can measure a difference, there has to be an audible difference.
  EDIT: Also, the letters section of the Audio Inquirer provides conclusive proof that Mr.Fremer is a rather unpleasant person.


----------



## 00940

Quote: 





nick_charles said:


> Bob Adams (Analog devices)   the youngest ever AES Fellow did a very good paper on jitter you can find a version of it in the back issues of The Audio Critic,
> 
> http://www.theaudiocritic.com/back_issues/The_Audio_Critic_21_r.pdf
> 
> he concluded that measuring jitter at the clock was almost always actually unnecessary as you can see it downstream in THD and IMD and if you read stereophile's measurements you will see that no device that has really bad jitter ever has good THD or IMD


 

  
  Thanks for the article, it's indeed very interesting and clearly written. This goes right to my collection  
	

	
	
		
		

		
			




   
  It should be said however that some bits (not many) are kind of outdated; jitter today is most commonly measured by reviewers through the analog output and not by sticking an oscilloscope on the internal clock output pin.Jtest and all that. You still need fairly good equipment for that FFT analysis though. Prism and AP products don't come cheap...


----------



## nick_charles

Quote: 





00940 said:


> You still need fairly good equipment for that FFT analysis though. Prism and AP products don't come cheap...


 

 A while back I was following a jitter test thread on the UK discussion forum HDD audio. A chap posted (added) jitter samples ranging from 0 to 100ns. I ran these through Audacity and was able to correctly place them in ascending order of jitter magnitude just by doing a spectrum analysis and plugging the results into Excel
  
http://hddaudio.net/viewtopic.php?pid=775#p775


----------



## 00940

ok, but you already had the digitized samples. The ADC job is the hardest part, especially if we're trying to hunt small differences.
   
  This said, no internet for me in the next days. I'll be back on the 23rd, hopefully with the copy of Paul Miller's USB cables measurements on hand.


----------



## NA Blur

[size=10pt][size=10pt]Other than noise, conductivity and thus impedance, and simple durability I cannot think of any other reason why an expensive hi-fi cable would alter the sound any.  Noise, conductivity, and impedance are pretty important though.  I remember in my physics days that nasty reflections and attenuations can occur from non-impedance matching.  This means that the impedance of your gear, headphones, and cable should ideally be the same.  Perhaps a higher quality cable has better grounding and slightly better impedance matching to headphones and headphone amps.  The same would go for speaker wire, speakers, and speaker amps.[/size][/size]
  [size=10pt] [/size]
  [size=10pt][size=10pt]I guess the price does not really matter, but the afore mentioned quantitative qualities do matter and will affect the sound.[/size][/size]
   
  [size=10pt][size=10pt]The following link shows the reflection coefficients for voltage down a transmission line relative to the impedance of two connected lines.  The only real way to preserve the amplitude and minimize the back reflection of other waves is to very closely match the impedance of each connection.[/size][/size]
   
  [size=10pt][size=10pt]http://en.wikipedia.org/wiki/Impedance_matching[/size][/size]
   
  [size=10pt][size=10pt]Here is another link specifically referring to audio equipment impedance matching:[/size][/size]
  [size=10pt][size=10pt]http://hyperphysics.phy-astr.gsu.edu/hbase/audio/imped.html[/size][/size]


----------



## DaBomb77766

Quote: 





na blur said:


> [size=10pt][size=10pt]Other than noise, conductivity and thus impedance, and simple durability I cannot think of any other reason why an expensive hi-fi cable would alter the sound any.  Noise, conductivity, and impedance are pretty important though.  I remember in my physics days that nasty reflections and attenuations can occur from non-impedance matching.  This means that the impedance of your gear, headphones, and cable should ideally be the same.  Perhaps a higher quality cable has better grounding and slightly better impedance matching to headphones and headphone amps.  The same would go for speaker wire, speakers, and speaker amps.[/size][/size]
> [size=10pt] [/size]
> [size=10pt][size=10pt]I guess the price does not really matter, but the afore mentioned quantitative qualities do matter and will affect the sound.[/size][/size]
> 
> ...


 


  This is why we have a USB spec.


----------



## Talos

DaBomb's Quote: 





> I would agree that we cannot measure a system's "imaging" in any real sense.


 
   
  DaBomb's Quote: 





> As such, my view is ... our current equipment can measure everything that a cable change could possible affect.


 
   
  Do you not think those two statements are contradictory?  For example, I would claim that one of the audible benefits I perceive of my Nordost USB cable (_vs_ a stock USB 2.0 cable) is an improvement in the precision of the imaging.  Are we both agreed that imaging as a real and perceptible, yet non measurable or quantifiable, property exists?
   
  ac500's Quote: 





> However if your DAC does run off a buffered source, and with its own local clock, then USB-dependent jitter simply should not be happening.


 
   
  I would take issue with that.  Jitter is not something that is _eliminated _by a buffer, it is only _reduced _by a buffer.  All we can hope to do is reduce it to a level below the threshold at which it can have a theoretically audible effect.  In one of my earlier posts I gave my rationale for suggesting that 24/192 audio is susceptible to jitter at levels which fall deeply below the ability of instrumentation to measure it, let alone eliminate it.
   
  ac500's Quote: 





> I wonder if anyone with a buffered DAC would comment.


 
  I have direct experience with two high-quality buffered DACs.  One is the Calyx 24/192 DAC and the other is a Classé CP-800 preamplifier with a built-in USB DAC.  Both use buffers, but both go beyond the "first-order" effect of _buffer _vs _no buffer_.  The Calyx uses two totally independent clocks for buffering.  One clock is used for the 44.1/88.2/176.4 family of sample rates, and the other is used for the 24/48/192 family.  This approach has resulted in an extremely high quality sound.  The Classé goes one step further.  It uses totally independent clocks for each and every sample rate it supports.  The Classé sounds even better than the Calyx.  Indeed, it is the best sounding USB DAC I have _ever _heard (I am not claiming I have heard them all), so I bought it.  Neither of these gems can claim to eliminate jitter (I don't speak for either manufacturer, but I am sure they would concur), but I think they both do a great job of reducing it.
   
  I also want to comment that jitter is a complex phenomenon.  To say that it can be "measured" is somewhat misleading.  Its _presence _can be measured, but its _nature _cannot.  How to explain this?  It is like the "decibel" app on my iPhone - it can measure the overall volume of the sound it hears, but it does not say anything descriptive about the sound, such as what tune is playing.  So, two different sources can have the same measurable amount of jitter, yet sound very different.
   
  I would make one further comment on the effect of buffers on jitter, with no basis other than my own personal observations to support it:  The jitter present in the output of a buffer designed to reduce it, will still be dependent to some extent on the jitter present in the source data stream.  In other words, the sonic signature of a system comprising such a buffer will, to the extent that jitter has any audible effects, still be dependent on the jitter characteristics of the original incoming data stream.


----------



## Talos

Quote: 





> This is why we have a USB spec.


 
   
  The USB spec is concerned with data integrity, and has little or nothing to say about jitter at levels which will have - I think we are agreed - an audible effect in a PCM data stream.


----------



## ac500

_> All we can hope to do is reduce it to a level below the threshold at which it can have a theoretically audible effect. _
   
  Yes, but a buffer will remove any clock dependence on the USB cable, and any "jitter" would be from a local clock, which would be absurdly low jitter - and in reality it would then become a DAC quality issue as opposed to a USB issue anyway.
   
_> The jitter present in the output of a buffer designed to reduce it, will still be dependent to some extent on the jitter present in the source data stream.  In other words, the sonic signature of a system comprising such a buffer will, to the extent that jitter has any audible effects, still be dependent on the jitter characteristics of the original incoming data stream._
   
  As you put it, "I take issue with this". A proper buffer will completely isolate the USB clock away from the DAC, and therefore completely eliminate any jitter that results from the USB source.
   
  I'd like to hear your explanation on why you claim this. Please no voodoo or magic-based explanations.


----------



## Prog Rock Man

A 1974 BBC study on jitter and its audibility.
   
  http://downloads.bbc.co.uk/rd/pubs/reports/1974-11.pdf
   
  The conclusion is that 35ns rms sinusoidal jitter, in frequencies above 2kHz would be audible to 5% of the population, for random jitter it is 50ns rms from 30Hz to 16kHz. So for a few extremes of jitter are audible. But that is with measurements in one billionths of a second, yet here I see arguments about jitter measured at pico seconds or one trillioth of a second, or a billionth of a nanosecond.
   
  It is absolutely astounding what audiophiles claim, with no evidence and significant evidence to the contrary, that they can hear.


----------



## rohan575

10101010101010101010   That's it! simple, on or off, 1 or 0, 0v or +5v. Only if it were so simple, we presume that digital signals are "clean" 1's and 0's sadly they are not. When things are happening so fast (a few megahertz) things can go crazy inside a cable. Inductance, interference, jitter, loss etc..etc..
   
  and there's the best of them, what is 2.5v? 1 or 0?  
   
  a cable's job is to deliver information from one place to another. Digital circuits have to be able to differentiate between, garbage and signal, the more garbage the cable adds the more it gets difficult for the circuit to differentiate between them. Soon, it may make mistakes of confusing noise as 1's or 0's which is avoided by other fancy stuff such as modulation and encoding.  Sadly, apart from providing the write electrical "connectivity" where fibers don't break in between and uniform in dimensions, there not quite much cables can actually do!
   
  Simple rule, sturdy, tight and short  , and a good sturdy connector always help , if you know hat i mean 
   
   
  And a 2400$ cable ! woof! I'd like to meet the guy who markets such stuff.
   
  P.s vote up if you think there should be standards in audio equipment which is tested by an independent lab to provide true information and not fool people.


----------



## Iniamyen

Quote: 





talos said:


> I also want to comment that jitter is a complex phenomenon.  To say that it can be "measured" is somewhat misleading.  Its _presence _can be measured, but its _nature _cannot.  How to explain this?  It is like the "decibel" app on my iPhone - it can measure the overall volume of the sound it hears, but it does not say anything descriptive about the sound, such as what tune is playing.  So, two different sources can have the same measurable amount of jitter, yet sound very different.


 

 Jitter can be measured. And its effects on the analog signal can be mathematically and experimentally confirmed. Yes, yes they can. What that does to the "sound" is totally in your head, so you have a point there. A point that no one has any interest in arguing...
   
  edit: I guess some people want to argue


----------



## svyr

>And a 2400$ cable ! woof! I'd like to meet the guy who markets such stuff.

in a dark alley. with no cameras... and a cleansing baseball bat (cricket bat as it may be in Australia  ?) 

>The conclusion is that 35ns rms sinusoidal jitter, in frequencies above 2kHz would be audible to 5% of the population, for random jitter it is 50ns rms from 30Hz to 16kHz. So for a few extremes of jitter are audible.

heh. considering most modern DACs have 10-50ps not ns ...  and 35ns = 35 000ps ... That's a whooping 4 orders of magnitude or 2-3 for the not so good devices.


----------



## ac500

I think no matter how much scientific evidence we provide proving that the difference can't be heard, the believers will always claim it makes a difference.
   
  For this reason I think the whole technical discussion is ultimately pointless. I think double blind testing is really the only undisputable way to prove whether there's any difference. People will always find a way to say "well your SCIENCE and MEASUREMENTS are faulty, all that matters is what you think you hear." To that, a double blind test is the perfect response, because it's the perfect measure of just that: what you hear.
   
  Look, this thread has gone on for 45 pages. FORTY FIVE PAGES. Have we gotten anywhere arguing technicalities (with people who really don't understand digital processing to begin with)? I say anyone arguing that USB cables makes a difference should be required to refrain from posting unless they post actual double-blind data. This may seem one-sided, but:
   
  a) This is the science forum.
  b) We're not allowed to talk about double-blind outside of the science forum, so the reverse seems fair to me.
  c) All peer-reviewed studies shows that there is no difference.


----------



## Prog Rock Man

Quote: 





ac500 said:


> I think no matter how much scientific evidence we provide proving that the difference can't be heard, the believers will always claim it makes a difference.


 



 That issue is redundant as there is no doubt that people do hear differences and there may be a absolute reality to those heard differences i.e. they are not fooling themselves. We are proving that the differences that are heard are not caused by the cable itself, instead they are down to the listener themselves.


----------



## leeperry

prog rock man said:


> That issue is redundant as there is no doubt that people do hear differences and there may be a absolute reality to those heard differences i.e. they are not fooling themselves. We are proving that the differences that are heard are not caused by the cable itself, instead they are down to the listener themselves.


 

 Yes, they're all mentally divergent. Your 37 year old scientific studies on jitter audibility nail it hard. really. I'm not. Kidding. Not Even. A bit.


----------



## Talos

Quote: 





> I think no matter how much scientific evidence we provide proving that the difference can't be heard, the believers will always claim it makes a difference.


 
   
  I don't know why everybody is getting so hot under the collar.  After all, as you point out, this is a science forum, and all I am trying to do is point out areas where science might have something useful to say on the topic, which is, in case we forget, "_I don't get why audiophile USB cable would improve sound quality_".  I don't think I have been dissing anybody.  It is not disrespectful to address somebody's viewpoint with a reasoned counter-argument.  I am open to that myself. 
   
  I have pointed out a scientifically valid explanation for why the jitter threshold for 24/192 audio could be as low as 310 femtoseconds.
  I have pointed out a scientifically valid explanation for why a USB cable's properties might affect the jitter in the range of hundreds of picoseconds and below.
  I have tried to point out that some aspects of jitter are measurable, whereas some are not.
  I have tried to point out that any theoretical analysis of the measurable effects of jitter on the audio signal is difficult, if not impossible.
  I have tried to get some measure of acceptance of the notion that some things which are audible are not measurable.
   
  I don't believe I am foisting any radical voodoo or scientific pseudo-babble on anybody.
   
  Taken together, all these observations add up to a basis for postulating that there is a reasonable argument to be made that a USB cable _can _impact the sound quality of a high end audio system.  Further, I am pointing out that this may even be true despite the fact that nobody can tell you what those audible effects could or should be, not can they tell you what to go away and measure in order to verify or deny the existence of such effects.  That's all.
   
  But instead, I am reduced to a "_believer_", a term used dismissively, if not pejoratively.  On the other hand "_no matter how much scientific evidence we provide_" attempts to stake out the rational high ground, based on ... what, exactly?.
   
  Sorry, but if this is a Science Forum, I'm Obama's mullah.  I won't be back, and I'm sure I won't be missed.


----------



## ac500

I don't think anyone -- well at least I was not calling you a "believer" in the negative sense, Talos. I was making an off topic observation of the fact that there was 45 pages of discussion on this anyway. The easiest way to conclude this thread is to do a double blind test on someone who claims they can hear a difference reliably with their cables.
   
  In any case I'd still like to hear how you think a buffered DAC input stream running on a local clock can receive jitter effects from an external clock.


----------



## Prog Rock Man

Quote: 





leeperry said:


> Yes, they're all mentally divergent. Your 37 year old scientific studies on jitter audibility nail it hard. really. I'm not. Kidding. Not Even. A bit.


----------



## Prog Rock Man

Quote: 





talos said:


> I don't know why everybody is getting so hot under the collar.  After all, as you point out, this is a science forum, and all I am trying to do is point out areas where science might have something useful to say on the topic, which is, in case we forget, "_I don't get why audiophile USB cable would improve sound quality_".  I don't think I have been dissing anybody.  It is not disrespectful to address somebody's viewpoint with a reasoned counter-argument.  I am open to that myself.
> 
> I have pointed out a scientifically valid explanation for why the jitter threshold for 24/192 audio could be as low as 310 femtoseconds.
> I have pointed out a scientifically valid explanation for why a USB cable's properties might affect the jitter in the range of hundreds of picoseconds and below.
> ...


 



 The terms (non)believer or subjectivist/objectivist are just convenient short descriptives of the different sides of the debate. The problem with much of the believer side's evidence is that it is untested speculation.


----------



## svyr

ahoy mateys. 

well now, usb.org have actually replied. 

may the light of non-placebo and 'omg I feel the powarh and warmth of mai cable' be witu and stuffs  

http://www.head-fi.org/forum/thread/565791/on-usb-cables-and-controller-transfer-modes-a-series-of-questions-to-replies-from-usb-org


----------



## Willakan

It baffles me how people can still maintain that the cable "designers" know better than the people who designed the entire specification.


----------



## svyr

willakan said:


> It baffles me how people can still maintain that the cable "designers" know better than the people who designed the entire specification.




it also baffles me that no one bothered to ask the specs people before, since they're kinda partially there for this kind of thing and it seems will gladly exorcise the infernal audiopedophile unicorn with us. although I'm pleased to report for me and you they just confirm what we thought  ... on the other hand, I'm sure the devotees of magical 'thickness of your usb cable is proportional to soundstage' clan will no doubt claim their setup is polluted by evil EMI and their cables save them. 
alas, not much we can do for them but *patpatpat*

anyway, hopefully that makes a meaningful contribution to 'buy properly designed gear and to spec cables' rather than wasting money on snakeoil bs.


----------



## ac500

svyr: Thank you! Very good info from the true experts on this subject.
   
_> It baffles me how people can still maintain that the cable "designers" know better than the people who designed the entire specification._
   
  What saddens me even more is how so many people on these forums will now be inevitably be trying to argue with the words from the people who designed the thing (USB). Remember the earlier comments by a poster (who I won't name) who said, _specifically_, that he distrusts and disrespects engineers and scientists. Reminds me of the phrase 'biting the hand that feeds you'.


----------



## Prog Rock Man

So USB.org don't get why "audiophile" USB cable would improve sound quality.
   
  It is worth pointing out that no audiophile cable company has any official endorsements, no peer reviews of their science, nothing. I would be convinced if USB.org put their name to an audiophile cable confirming that it improves sound quality.


----------



## upstateguy

Quote: 





prog rock man said:


> So USB.org don't get why "audiophile" USB cable would improve sound quality.
> 
> It is worth pointing out that no audiophile cable company has any official endorsements, no peer reviews of their science, nothing. I would be convinced if USB.org put their name to an audiophile cable confirming that it improves sound quality.


 


  Your original question is still the best. * Why* do some people hear differences?


----------



## chinesekiwi

Quote: 





upstateguy said:


> Your original question is still the best. * Why* do some people hear differences?


 

 Psychoacoustics via expectation bias.


----------



## b0ck3n

The question "why?" has been answered. The sad part is that there's a general unwillingness to admit to oneself that one is under the influence of placebo. It's human nature and we're all susceptible to it to varying degrees.


----------



## JuicyBruce

deleted


----------



## anetode

Quote: 





prog rock man said:


> So USB.org don't get why "audiophile" USB cable would improve sound quality.
> 
> It is worth pointing out that no audiophile cable company has any official endorsements, no peer reviews of their science, nothing. I would be convinced if USB.org put their name to an audiophile cable confirming that it improves sound quality.


 
   
  I, for one, expect any company actively engaging in consumer fraud by marketing grossly overpriced USB cables to at least have the common decency to bribe a non-profit's official or at least a well-respected academic to support or lend credence to their product. Drop 100k on buying an AES recommendation and I'm sure the increase in sales will more than make up for the investment. But then we have these hoighty-toighty professional organizations with their "ethics codes" and adherence to validated science, for shame!


----------



## svyr

anetode said:


> I, for one, expect any company actively engaging in consumer fraud by marketing grossly overpriced USB cables to at least have the common decency to bribe a non-profit's official or at least a well-respected academic to support or lend credence to their product. Drop 100k on buying an AES recommendation and I'm sure the increase in sales will more than make up for the investment. But then we have these hoighty-toighty professional organizations with their "ethics codes" and adherence to validated science, for shame!




AES proph measurement and DBT =) they'd want a repeatable procedure and someone will likely publish a paper retesting... so um yea, but no.


----------



## nicholars

Has anyone noticed that the people who report differences always report these differences in areas which are completely subjective and non measurable?
   
  Examples of these "perceived differences" are : Improved soundstage, increased air between instruments etc.
   
  I notice that people who report improvements between USB cables it is always in these areas which are so subjective and so easy to just imagine a difference.


----------



## drez

This is often true - qualities such as soundstage and instrument separation are quite difficult to pin down.  This could possibly be because many cables are all but indistinguishable - in my experience differences between say one copper USB cable and another are almost impossibly to cleary tell.  Much like with an SPDIF cable once you have a constant impedance (90 ohms for USB) changes are difficult to discern and to be honest from a technical standpoint this is what you would expect.  After having constant impedance, some cables have silver plated conductors which apparently can improve the signal waveform integrity by creating a more constant impedancy/frequency curve.  This probably depends a lot on the wire gauge, plate thickness etc and to be honest could be complete nonsense unless the cable designer shows some numbers to back this claim up.  The last thing that in theory can affect USB cable performance is cable length - where a shorter cable of the same construction should give better jitter performance as predicted by the USB standard paper.  The last factor is the succeptibility of the USB audio interface itself to jitter, along with other factors which may introduce jitter or noise into either the D/D converter or directly into the DAC.
   
  You are quite right that soundstage and instrument separation are qualities which are rather easy to get confused about, and also in my experience many digital cables I have tested are very difficult to tell apart - I'm pretty sure I would fail a blind test with say 75 ohm SPDIF cables or USB cables of the same length and conductor type.  Personally I have heard more differences between USB ports and galvanic isolators than between different copper USB cables.  BUT I am personally quite certain I can discern between a copper USB cable and the silver plated copper cable I am using, and equally there is evidence that in theory different USB cables have different levels of jitter.  BUT the effects of jitter on D/D and D/A converters is fairly controversial, in no small part because there are innumerable variables in terms of hardware, but mostly because it is relatively simple to demonstrate that relatively large magnitudes of jitter (beyond that of any decent equipment) are not audible.
   
  As you can see I personally am in quite a precarious position - I am forced to admit that on an priorised-knowledge level one cannot clearly predict that jitter will be audible.  However, based on experience I can say that elements such as USB cables have lead me to experience and articulate clear differences between USB and computer side hardware and software changes which I cannot readily explain and yet which I would not put down to cognitive bias.  As I already said I like to think I am willing to concede when I cannot clearly hear differences or when I hear negative differences.  When this happens I sell equipment very quickly as I would rather spend the money elsewhere.  Life would be much easier if I were an electrical or audio engineer researcher and had access to lab equipment to measure either electrical waveforms or jitter or even distortion levels at the output of the DAC.  Unfortunately most Audiophile tweaks are very short on technical insight and reliant upon anecdotal evidence to measure performance - and while I do not personally consider myself an objectivist - the points mentioned in this post, along with the preceding 45 pages of discussion should act as a warning not to spend too much money on digital cables.
   
  EDIT: This is probably not that important but I feel I should mention that personally I prefer to focus on other factors such as bass bloom/tightness, midrange smoothness or grain, and imaging and focus (ie how clear the outline of an instrument can be discerned) along with upper midrange and treble fatigue.  These qualities are again not foolproof, but I personally find these easier to discern that soundstange and "air around instruments".  Best thing to do I would say is once you have selected a DAC -see if you can borrow a fairly short silver plated copper USB cables to compare against the generic USB cable - If you cant hear a clear difference then obviously it is not worth buying such a cable.


----------



## nicholars

To be honest I cannot even be bothered to mess around trying USB cables until I see some hard evidence other than subjective opinions which conclusively proves that a "audiophile USB" is going to make any difference at all.
   
  I am 99% sure that a reasonable quality USB cable will be completely fine to send the data to my async USB DAC.... The nature of this DAC should pretty much eliminate jitter and the cable of reasonable quality which conforms to USB standards should be 100% ok to transfer the data to the DAC.
   
  Companies like wireworld and all this IMO are scammers who are trying to make money from snake oil and expectation bias.


----------



## LizardKing1

Quote: 





drez said:


> Spoiler: Mega-post
> 
> 
> 
> ...


 
   
  I like your way of thinking, you have your personal impressions, but you don't give them more weight than what they deserve.
  About the jitter, when you said that the ammount of jitter wasn't audible, it made it seem like jitter directly correlates with distorted music (analog). I was under the impression that up to a certain limit of jitter introduced to a USB signal, it would still get correctly decoded and so you still get bit-perfect stream. Kind of like how you can take a perfect drawing of a face and re-draw it worse each time, until at a certain point people can't tell what it was originally anymore.


----------



## nicholars

What difference does a 75ohm cable make over a normal one?


----------



## ArcAngel66

In a way, it makes zero sense  why certain usb cables sound different but, from my own listening, they do.
   
  I was at Frys Electronics and saw one of these:
   

   
  My DAC is rather small (HRT Music Streamer II+), and so I could easily stick it right up to my Mac Mini to hook it up using this (bigger DACs, I doubt it would be possible).
   
  After trying it, it turns out that this stupid little $2 adapter sounded a ton better (instruments were more separated, and not as "blurred" together) than various $30 Belkin/Monster cables. I have no clue why, but I just assume it may be due to it being basically the shortest USB "cable" possible.
   
  Quote: 





nicholars said:


> To be honest I cannot even be bothered to mess around trying USB cables until I see some hard evidence other than subjective opinions which conclusively proves that a "audiophile USB" is going to make any difference at all.
> 
> I am 99% sure that a reasonable quality USB cable will be completely fine to send the data to my async USB DAC.... The nature of this DAC should pretty much eliminate jitter and the cable of reasonable quality which conforms to USB standards should be 100% ok to transfer the data to the DAC.
> 
> Companies like wireworld and all this IMO are scammers who are trying to make money from snake oil and expectation bias.


 
   
   
  While certain claims these companies make are certainly puffing the results of these cables, what company doesn't do that? Apple's iPad is "Magical" you know 
   
  Wireword uses a flat cable design that physically separates the power conductor from the other conductors. I own a Wireworld Starlight and it certainly sounds better than other cables I've used. While it's not the cure-all for your audio system, I think that design is a smart idea and a high quality cable.
   
   
  Why do USB cables sound better/different? Not a clue. But my ears definitely hear a difference. It may just depend on the DAC (being powered from the USB cable, or elsewhere?). It may just be the fact that they have higher quality materials.
   
   
  One last question I've read on another forum:
   
  If these "digital" cables are bit-perfect and either work or don't work... Then why do a ton of USB cables (my mouse, my keyboard, and tons of others) have Ferrite Cores on them? That's a question I haven't seen an answer to.


----------



## liamstrain

Quote: 





arcangel66 said:


> If these "digital" cables are bit-perfect and either work or don't work... Then why do a ton of USB cables (my mouse, my keyboard, and tons of others) have Ferrite Cores on them? That's a question I haven't seen an answer to.


 
   
  I don't know. None of mine have them. It could be just cheap insurance from manufacturers who skimped on shielding.


----------



## uelover

Quote: 





arcangel66 said:


> In a way, it makes zero sense  why certain usb cables sound different but, from my own listening, they do.
> 
> I was at Frys Electronics and saw one of these:
> 
> ...


 
   
  I have been trying all ways to rely solely on adapter but it is just impossible. Can't stick my gears beside each other. If there are companies that build their gears like a Lego brick, it would be great!
   
  As much as I hate spending money on cable, I have to agree with your experience that they do make a difference in sound and that pisses me. On paper, they shouldn't. We all know that.
   
  On some gears, I don't hear any difference while on others, I do. It could be that the USB receiver unit is not as good and that tells me I should be putting my money in that area instead. However, that does not explain the problem here.
   
  How much money should we spend on getting a 'high' quality USB cable? That question is beside the point.


----------



## Yoga Flame

Quote: 





arcangel66 said:


> If these "digital" cables are bit-perfect and either work or don't work... Then why do a ton of USB cables (my mouse, my keyboard, and tons of others) have Ferrite Cores on them? That's a question I haven't seen an answer to.


 
   
  They're also used to filter the noise generated by the device itself so it doesn't interfere with other devices.


----------



## nicholars

Hmmm well to me it seems like "expectation bias". "Psycho acoustics" is a powerfull thing and I would be willing to bet that in a BLIND test where you couldnt see what cable it was that you probably wouldnt be able to tell a difference. It is a data cable transferring data to the DAC. The usb specification would mean that a reasonable quality cable will pass all the information bit perfect and especially if you are using an async dac I really cannot see why I would make any difference other than psycho acoustic reasons. eg. you look at your nice shiny cable and for some reason it just sounds better... It just does... Yes it does sound better but not because the cable is better but because you think it does. In reality the sound is probably identical to a bog standard USB cable.
   
  The same way if you were to take a load of drugs or something... The music would sound absolutely amazing to you... But in reality it is exactly the same sound quality that sounded horrible the other day when you woke up with a hangover lol.


----------



## drez

Quote: 





arcangel66 said:


> Spoiler: Warning%3A%20Spoiler!
> 
> 
> 
> ...


 
   
  The ferrite is there to absorb some high frequency noise.  If properly engineered ferrites can be very effective at this.  If just clamped around a cable then the results may vary.
  Quote: 





nicholars said:


> Hmmm well to me it seems like "expectation bias". "Psycho acoustics" is a powerfull thing and I would be willing to bet that in a BLIND test where you couldnt see what cable it was that you probably wouldnt be able to tell a difference. It is a data cable transferring data to the DAC. The usb specification would mean that a reasonable quality cable will pass all the information bit perfect and especially if you are using an async dac I really cannot see why I would make any difference other than psycho acoustic reasons. eg. you look at your nice shiny cable and for some reason it just sounds better... It just does... Yes it does sound better but not because the cable is better but because you think it does. In reality the sound is probably identical to a bog standard USB cable.
> 
> The same way if you were to take a load of drugs or something... The music would sound absolutely amazing to you... But in reality it is exactly the same sound quality that sounded horrible the other day when you woke up with a hangover lol.


 
   
  Hmm something makes me think you resurrected this thread just to troll rather than to ask questions or gain insight, so I may consider adding you to my block list.  Making sweeping generalisations and assumptions is not scientific or logical thinking.  You know expectation bias cuts both ways - if you listen and don't expect to hear a difference this is likely what you will experience.  As I have stated previously I have tested components regardless of price which I did not perceive to bring performance benefits and I sold them.  It is rude to constantly insist that opinions people are offering are due to expectation bias.  Get some manners.
   
  Asynchonous USB interfaces are not very succeptible to jitter originating in a USB cable or the USB controller - they can however pass on noise and are not completely immune to jitter.  "Jitter immune" is more marketing nonsense than cable manufacturers selling high performance USB cables.  Bit perfect is another misleading term, as you can have massive quantities of jitter which lead to (audible) distortion and yet have a bit perfect stream.  If you have a good asynchronous USB interface then buying a USB cable will probably not deliver massive, day and night differences, but again there are too many factors here to say this conclusively.
   
  A 75 Ohm SPDIF cable has a constant impedance which reduces the possibility for signal reflections within the cable whcih occur when there is an impedance change.
   
  Being prudent with your spending on hi-fi gear is wise, but in the end you have to use your ears to select components such as DAC, amplifier and headphones.  Many audiophiles take this further and select cables and USB interfaces by ear, and in many cases if the DAC is good enough they hear no difference and sell the USB interface.  Please do not misinterpret this to be evidence that all USB cables are the same - it is merely an example of what I consider to be prudent testing of audio equipment.  Other people have tested USB cables and not found any audible differences with the equipment they use, I'm fine with this also and consider their experience more than valid.  In my own experience I have also found that due to my lack of experience in audio my evaluation of even the most concrete modification (eg an earpad change) is liable to change with time, therefore I like to hold onto components for at least 3 months to allow me to properly understand what I am hearing.  I should also add that I too have tested USB adapters and found them to be superior to even $100+ USB cable I own, and because of this I use the USB adapter and not the more expensive cable.
   
   
  Use the knowledge from your research and discussion to inform how you select and evaluate components as this is a fruitful way to spend your energy.  I would not suggest trying to use your meager knowledge to try and tell other people that they are wrong on the internet, as this is not going to get you anywhere except on peoples block list.


----------



## nicholars

lol please carry on and block me I really couldnt care less... I was merely giving an opinion as to the probable reason why these people are hearing differences when there has been repeated proof of no measurable differences between usb cables. Infact please do block me beacuse I would prefer not to speak to you again if you are going to insult me for giving a perfectly reasonable explanation!
   
  My intentions for my post was to possibly discourage people from buying from companies like wireworld which are clearly extorting customers with borderline illegal marketing and sales tactics... By all means carry on and buy it if it makes you happy I was merely giving another viewpoint.


----------



## LizardKing1

I think what drez was saying was that although he's aware of expectations bias and all those effects, that still doesn't detract from the fact that he hears a consistent difference between USB cables, although he knows that theoretically there shouldn't be one. Of course if this was under blind testing it would have more weight.
   
  Also a lot of the people who hear differences between cables usually hear huge differences between setups with minute changes - or even in setups where there's no difference, if the tester is feeling particularly cruel. So considering that he admitted to hear no difference between certain snakeoil cables and sold them, it gives a certain weight to his opinion when he does hear them. Kind of like in |joker|'s IEM review, when he says he hears no difference from burn-in in the majority of models, when he does hear a change after time it's normal to assume that you will too. If it was someone who reported "night and day" differences from burn-in with most models, you would assume expectation bias was more at play.


----------



## anetode

drez said:


> As I have stated previously I have tested components regardless of price which I did not perceive to bring performance benefits and I sold them.  It is rude to constantly insist that opinions people are offering are due to expectation bias.  Get some manners.




Sir, I think perhaps you might be susceptible to a variety of cognitive distortions when you attribute the following audible effects to a physical change that evidence suggests is beneath the threshold of audibility.

vs.

You're an idiot and it's in your head and you smell bad.


One does not have to take any reference to psychoacoustics as an aspersion. Doing so, from this reader's point of view, reflects little more than insecurity.


----------



## sridhar3

Quote: 





anetode said:


> you smell bad.


 
   
  I think that would hold true regardless of whether or not he hears a difference when using different cables.


----------



## anetode

Everyone knows that bad smells are a perceptual delusion primed by expectation bias.

/that's my excuse


----------



## nicholars

It is very possible that he does smell bad although this may be a result of expectation bias due to his remarks.
   
  Considering this from an objective viewpoint I would conclude that, although there are no double blind, placebo controled studies to confirm this I would assume that he probably does smell bad.


----------



## Anaxilus

Quote: 





nicholars said:


> Considering this from an objective viewpoint I would conclude that, although there are no double blind, placebo controled studies to confirm this I would assume that he probably does smell bad.


 
   
  What?  According to that viewpoint he shouldn't smell like anything and you would have no assumptions..


----------



## nicholars

But objectively based on his comments and general attitude towards my comments that would indicate that he is more likely to smell then to not smell although it could be argued that my opinion on this is subjective.


----------



## sridhar3

Quote: 





nicholars said:


> But objectively based on his comments and general attitude towards my comments that would indicate that he is more likely to smell then to not smell although it could be argued that my opinion on this is subjective.


----------



## tmars78

Quote: 





nicholars said:


> lol please carry on and block me I really couldnt care less... I was merely giving an opinion as to the probable reason why these people are hearing differences when there has been repeated proof of no measurable differences between usb cables. Infact please do block me beacuse I would prefer not to speak to you again if you are going to insult me for giving a perfectly reasonable explanation!
> 
> My intentions for my post was to possibly discourage people from buying from companies like wireworld which are clearly extorting customers with borderline illegal marketing and sales tactics... By all means carry on and buy it if it makes you happy I was merely giving another viewpoint.


 
   
   
  Some people don't take kindly to being told they are "wrong". Some people don't realize just how easy your mind can make up things that are not there.. The mind is a wonderful thing. If I spent $1,000 on a cable, and it made a huge improvement to the sound I hear, I would be happy with that, even if it was in my mind. It is not wrong to hear differences, it is wrong however, to attribute them to the cable. I am a non-believer in cables, and would LOVE to do a DBT on all kinds, from $1 ones to $100,000 ones. Unfortunately I cannot afford the higher end ones. Most believers wouldn't do the DBT if I bought every cable, flew them to my place, and offered them $10 million dollars if they can pass the DBT. They would somehow find a flaw in the test, my gear, or something. No one wants to admit they've been duped into spending a huge sum of money for something that can be had from monoprice for pennies on the dollar.


----------



## proton007

If it were the audio cable, there's a miniscule chance of debating the wire characteristics affecting the audio.
  For USB, no chance. As long as your device runs error checking (bulk transfer) mode, which most devices do, there's no such thing as some data being better than the other. Either digital data is transferred correctly, or it isn't. END OF STORY.


----------



## liamstrain

Even in async, there is very little that can affect the cable aspect of the signal transfer.


----------



## proton007

Quote: 





liamstrain said:


> Even in async, there is very little that can affect the cable aspect of the signal transfer.


 
  +1


----------



## maverickronin

Quote: 





proton007 said:


> If it were the audio cable, there's a miniscule chance of debating the wire characteristics affecting the audio.
> For USB, no chance. As long as your device runs error checking (bulk transfer) mode, which most devices do, there's no such thing as some data being better than the other. Either digital data is transferred correctly, or it isn't. END OF STORY.


 
   
  Most all DACs don't run in that mode.  They're stream of consciousness bitstreams with no error correction.    A better quality cable could make tiny little differences in jitter far below what has been demonstrated to be audible but that's about it.
   
  Voldemort said he was probably going to test the ODAC with some USB cables with and without ferrites and USB isolators.


----------



## mikeaj

The only jitter that really matters in the end is whatever that affects the DAC, making each output sample not be of exactly equal time duration (jittery).
   
  If there's jitter on the USB connection, who cares, unless the DAC is clocked by the USB transmission?  Unless you're looking at a pretty low-end product, most DACs have a crystal-controlled oscillator on board and get the timing from that, right?


----------



## drez

.


----------



## proton007

Quote: 





mikeaj said:


> The only jitter that really matters in the end is whatever that affects the DAC, making each output sample not be of exactly equal time duration (jittery).
> 
> If there's jitter on the USB connection, who cares, unless the DAC is clocked by the USB transmission?  Unless you're looking at a pretty low-end product, most DACs have a crystal-controlled oscillator on board and get the timing from that, right?


 
  Yep.
  Once the data is reliably transferred, the jitter due to the cable should not affect the DAC sampling.


----------



## drez

Quote: 





anetode said:


> Sir, I think perhaps you might be susceptible to a variety of cognitive distortions when you attribute the following audible effects to a physical change that evidence suggests is beneath the threshold of audibility.
> vs.
> You're an idiot and it's in your head and you smell bad.
> One does not have to take any reference to psychoacoustics as an aspersion. Doing so, from this reader's point of view, reflects little more than insecurity.


 
   
  Well I would suggest you use some more advanced comprehesnsion skills in order to appraise the tone of Nicholar's posting.
   
  I am very willing to note that my observations may be affected by cognitive bias, on the other hand many freshling objectivists are not willing to concede that they are merely regurgitating second or third hand opinion and are clearly not familiar with either the technical or scientific foundations of these viewpoints.  This is not constructive.
   
  Consider this:  A person has read the Bible and find it to be a very convincing body of evidence that a Judeo-Christian God exists.  Someone else reads George Orwell and decides that there is no God and all Christians are wrong.  If this fan of George Orwell goes around telling Christians that they are foolish because George Orwell has some convincing arguments is this polite?  I am more than willing to accept the viewpoint of skeptics who have actually tested and experimented with the technology, who have a good understanding of the technical concepts, and who have taken time to properly understand the precepts of the scientific basis for arguments against the audibility of jitter.


----------



## liamstrain

So... just to clarify. You are ok with unverifiable opinions, as long as it is subjective and biased. Someone citing actual research and data (or someone else's analysis of those) must be fully fluent in the field before doing so? Or you just want them to admit that is what they are doing?


----------



## proton007

Quote: 





drez said:


> Well I would suggest you use some more advanced comprehesnsion skills in order to appraise the tone of Nicholar's posting.
> 
> I am very willing to note that my observations may be affected by cognitive bias, on the other hand many freshling objectivists are not willing to concede that they are merely regurgitating second or third hand opinion and are clearly not familiar with either the technical or scientific foundations of these viewpoints.  This is not constructive.


 
   
  Most of us are not even citing some research or data, we're just explaining how these things are actually designed and work. Their design objective is totally independent from their end usage. USB is used in much serious and sensitive scenarios than audio, and has been designed just to transfer data reliably. What you do with that data is your problem, not the cable's.
  I doubt it can be made simpler than that.


----------



## drez

Quote: 





proton007 said:


> Yep.
> Once the data is reliably transferred, the jitter due to the cable should not affect the DAC sampling.


 
   
  As far as I know it is not that simple.  It depends how effective the digital input section is at eliminating jitter [and whether upsampling is used] - some good DAC's use asynchronous USB with galvanic isolation (controlled by it's own clocks), or otherwise SPDIF input with galvanic isolation or a ferrite choke to stop any noise being transmitted further downstream.  After this a DAC will typically have an SPDIF receiver such as WM8805 which uses an oscillator but to my knowledge is an adaptive process and does not reclock the signal, and this chip typically outputs I2S signal.  From here many DAC's will upsample the signal with various digital filters to shift the jitter distortion out of the audible spectrum (typically controlled by a separate clock.)  Some DAC's will output I2S directly from the USB input rather than outputting SPDIF to an SPDIF receiver chip which is more direct but skips a possible stage of jitter reduction.
   
  An oversampling DAC with a well designed digital input section with galvanic isolation of the digital inputs will care little about the performance of the USB cable - and reviewers have already picked out these DAC's for example the Anedio D1, Antelope Zodiac, Calyx DAC and PSAudio Perfect Wave DAC.  Some well designed USB to SPDIF converters such as those from Audiophilleo also show little change between USB cables.


----------



## drez

Quote: 





proton007 said:


> Most of us are not even citing some research or data, we're just explaining how these things are actually designed and work. Their design objective is totally independent from their end usage. USB is used in much serious and sensitive scenarios than audio, and has been designed just to transfer data reliably. What you do with that data is your problem, not the cable's.
> I doubt it can be made simpler than that.


 
   
  digital data is not 1's and 0's it is in fact an electrical waveform.  Most USB equipment uses bulk mode transfer which has the ability to check incoming packets and resend them if necessary, and as far as I know there is only one DAC that uses this technology.  Most use either adaptive or asynchronous transfer modes which are fundamentally different both from bulk mode and from each other.
   
  If you are appraising a technology from an theoretical basis, you had better be familiar with the technology otherwise the discussion is pointless.


----------



## drez

Quote: 





sridhar3 said:


> I think that would hold true regardless of whether or not he hears a difference when using different cables.


 
   
  But if I denounced audibility of jitter and importance of cabling I would no longer be crazy and therefore be better able to maintain my own hygeine


----------



## liamstrain

It is a wave form, but it is also 1s and 0s. There is a lot of variation in that wave that registers as a 1 or 0. Quite shocking amounts of flux, in fact. The spec itself accounts for a good bit of gap:
   
   
  Quote: 





> Transmitted signal levels are 0.0 to 0.3 volts for low (0) and 2.8 to 3.6 volts for high (1) in full-bandwidth and low-bandwidth modes, and −10 to 10 mV for low (0) and 360 to 440 mV for high (1) in hi-bandwidth mode.


 
   
  And from what I understand, most devices have even more slop built in. Which means you can have noise in the wave form, affecting the voltages at least up to 10% and still be within spec.
   
  Clocking issues aside (and there is slop there too - Clock tolerance is 480.00 Mbit/s ±500 ppm, 12.000 Mbit/s ±2500 ppm, 1.50 Mbit/s ±15000 ppm) - since there is little agreement on whether even large amounts of jitter is audible - this allows for a properly encoded usb signal under even the ****tiest of conditions. And very little to suggest the cable makes much difference in this - especially a cable built to spec.


----------



## proton007

Quote: 





drez said:


> As far as I know it is not that simple.  It depends how effective the digital input section is at eliminating jitter [and whether upsampling is used] - some good DAC's use asynchronous USB with galvanic isolation (controlled by it's own clocks), or otherwise SPDIF input with galvanic isolation or a ferrite choke to stop any noise being transmitted further downstream.  After this a DAC will typically have an SPDIF receiver such as WM8805 which uses an oscillator but to my knowledge is an adaptive process and does not reclock the signal, and this chip typically outputs I2S signal.  From here many DAC's will upsample the signal with various digital filters to shift the jitter distortion out of the audible spectrum (typically controlled by a separate clock.)  Some DAC's will output I2S directly from the USB input rather than outputting SPDIF to an SPDIF receiver chip which is more direct but skips a possible stage of jitter reduction.


 
   
  Most chips have onboard USB support, with an on chip clock generator that is used for both the USB and Sampling clocks. 
  They use a FIFO to buffer the data received, and then it is clocked by the DAC. An I2S is not required because the data has already been transferred by the USB.
  Usually, an SPDIF/I2S out is implemented in case the data needs to be transferred further. 
  Hence, if the data packet has been received, jitter on the USB should not affect the DAC sampling.


----------



## drez

Quote: 





proton007 said:


> Most chips have onboard USB support, with an on chip clock generator that is used for both the USB and Sampling clocks.
> They use a FIFO to buffer the data received, and then it is clocked by the DAC. An I2S is not required because the data has already been transferred by the USB.
> Usually, an SPDIF/I2S out is implemented in case the data needs to be transferred further.
> Hence, if the data packet has been received, jitter on the USB should not affect the DAC sampling.


 
   
  I am not an electronics professional but to my understanding I have not heard of any DAC chips or designs that send USB signal directly to the DAC chip.  My limited understanding is that I2S is the usual format used to carry the PCM data from digital input receivers to the DAC chip.  I was under the (possible false) impression that a separate oscillator is used for sampling in most cases but I am not an expert here.
   
  Either way most decent DAC's use more than one buffer/filter to reduce jitter, and some DAC's use more/superior jitter reduction techniques than others, therefore are less likely to be affected by jitter.  Due to my lack of expertise I am also unsure about the relationship between jitter audibility and the DAC conversion process eg is this jitter being fed directly to the DAC without any filtering or not.
   
  Another possibility is that it is not jitter that is causing the problem after all and rather than some divices and cables transmit or pick up more noise which may or may not find its way to the DAC chip, eg whether the difference in performance or lack thereof depends entirely on whether a DAC or SPDIF interface uses galvanic isolation...


----------



## proton007

Quote: 





drez said:


> I am not an electronics professional but to my understanding I have not heard of any DAC chips or designs that send USB signal directly to the DAC chip.  My limited understanding is that I2S is the usual format used to carry the PCM data from digital input receivers to the DAC chip.  I was under the (possible false) impression that a separate oscillator is used for sampling in most cases but I am not an expert here.


 
  USB DAC is a pretty common integrated solution nowadays with either an On-Chip USB Controller. TI has a lot of those.
  Another common way to do this is to use a USB (Audio Class) Controller chip -> I2S out -> DAC, if you want to use separate chips. The I2S is very low jitter as the bus carries a separate clock signal. The DAC will use this data for over-sampling, with its own clock as you said.
   
  Quote: 





drez said:


> Either way most decent DAC's use more than one buffer/filter to reduce jitter, and some DAC's use more/superior jitter reduction techniques than others, therefore are less likely to be affected by jitter.  Due to my lack of expertise I am also unsure about the relationship between jitter audibility and the DAC conversion process eg is this jitter being fed directly to the DAC without any filtering or not.


 
  Usually the jitter will result after the filtering, and into the DAC stage.
   
  Quote: 





drez said:


> Another possibility is that it is not jitter that is causing the problem after all and rather than some divices and cables transmit or pick up more noise which may or may not find its way to the DAC chip, eg whether the difference in performance or lack thereof depends entirely on whether a DAC or SPDIF interface uses galvanic isolation...


 
  I think it should depend on how effective the USB/SPDIF receiver is at rejecting a noisy signal. Unless the cable noise is so bad that the data gets corrupted, the issue is more about whether your device receives all the packets the host sends. It will not matter if you use an expensive usb cable as long as its USB certified, because chances are that packets might be dropped still by the device, and the host won't know.
  So I guess the jitter is a characteristic of the host and the DAC design, rather than which cable is used as long as the cable is reliable.


----------



## drez

^Thanks for explaining that
	

	
	
		
		

		
		
	


	



   
  EDIT: Do you think it might be possible that when we are talking about DAC designs for example USB DAC chip with on-chip USB receiver that the level of noise either picked up or transmitted by the cable could find it's way past the filtering stage if there is no galvanic isolation.  In the case of digital transports such as the one I am using noise still doesn't go much distance toward suggesting a possible mechanism for the influence of USB cables on a DAC.
   
  If I am to understand Liamstrain posted in theory noise should not really affect the performance of an asynchronous USB receiver as there are large enough tolerances built in that there should not be any packet drops?  I guess though one would need to take into consideration the range of tolerances from the USB standard for the cable, to the USB standard for the USB controller, the level of noise on motherboard power supplies for the USB ports (or just measure the USB signal with an oscilloscope.)   "0.0 to 0.3 volts for low (0) and 2.8 to 3.6 volts for high (1) in full-bandwidth" does seem like quite a large tolerance and that if devices can tolerate up to 10% of these numbers in noise it would certainly seem pretty hard for the USB input to exceed these tolerances.  I am probably at risk of laboring over this point excessively but still I am curious.


----------



## proton007

No Problem.
  Quote: 





drez said:


> ^Thanks for explaining that
> 
> 
> 
> ...


 
  Past the filtering stage is unlikely. Noise in digital signal transmission usually does not affect its interpretation, unless it is causing swings in the voltage level. Hence, any data, if corrupted by such noise, will be used as such by the receiver if not checked for error.
   
  Quote: 





drez said:


> If I am to understand Liamstrain posted in theory noise should not really affect the performance of an asynchronous USB receiver as there are large enough tolerances built in that there should not be any packet drops?  I guess though one would need to take into consideration the range of tolerances from the USB standard for the cable, to the USB standard for the USB controller, the level of noise on motherboard power supplies for the USB ports (or just measure the USB signal with an oscilloscope.)   "0.0 to 0.3 volts for low (0) and 2.8 to 3.6 volts for high (1) in full-bandwidth" does seem like quite a large tolerance and that if devices can tolerate up to 10% of these numbers in noise it would certainly seem pretty hard for the USB input to exceed these tolerances.  I am probably at risk of laboring over this point excessively but still I am curious.


 
  Basically, the concept is this. All USB transfer types (Control, Bulk, Interrupt) except Isochronous, use a Token Packet -> Data Packet -> Handshake Packet during transfers.
  Token packets transmit the state of the host/device (ready/not ready), Data packets carry data, and Handshake packets transmit a final response from host/device (acknowledge/negative acknowledge/stall) to end a transaction.
  Isochronous transfers do not have the handshake packets, which means, the device will not acknowledge the receipt of data packets. Since timely transfer of data is more important for audio/video streaming, the host (your PC) may choose to drop certain packets if its not able to meet the bandwidth requirement (maybe busy doing other stuff, or the bus is too busy with other data).
  However, this does not mean there's no possibility of error checking. If a CRC is transmitted along with the packet, the device can perform an error check on its own. Whether that is of consequence is another issue. Since the device won't re-request the frame from the host, it can just drop the packet.
  So as you said, the tolerance for voltage is pretty high, so usually, the question is whether all packets are transferred reliably by the host, received by the device and not dropped. Windows can use ASIO for example, to minimize latency and give direct access to the sound card, bypassing the kernel mixer.


----------



## drez

I guess I'm stumped then - I cant really find a theoretical justification for the effect of USB cables on a DAC.
	

	
	
		
		

		
		
	


	




  I still admit that I have a preference for my better USB cable, but I will have to do some DBT before I can say with certainty that what I am hearing is a legitimate observation, but you can take my word that I am highly convinced by my preference such that even when faced with this overwhelming theoretical disproof I still can't help but trust what I seem to be hearing.  I am in a state of cognitive dissonance which at this stage I cannot resolve, but hopefully one of these days I will be able to resolve this either by conducting a DBT which produces positive results or otherwise.  This may be challenging though as the differences I have observed are that the generic cable has more grain and fatigue in the midrange, luckily one of them seems to hurt my ears while the other doesn't (I'm not kidding lol) so hopefully when if I get around to doing a DBT this observation and ear pain does not dissappear


----------



## proton007

Quote: 





drez said:


> I guess I'm stumped then - I cant really find a theoretical justification for the effect of USB cables on a DAC.
> 
> 
> 
> ...


 
   
  I think a DBT would be insightful. Maybe you can also chime in on the other thread about headphone cables.


----------



## LizardKing1

Quote: 





proton007 said:


> Basically, the concept is this. All USB transfer types (Control, Bulk, Interrupt) except Isochronous, use a Token Packet -> Data Packet -> Handshake Packet during transfers.
> Token packets transmit the state of the host/device (ready/not ready), Data packets carry data, and Handshake packets transmit a final response from host/device (acknowledge/negative acknowledge/stall) to end a transaction.
> Isochronous transfers do not have the handshake packets, which means, the device will not acknowledge the receipt of data packets. Since timely transfer of data is more important for audio/video streaming, the host (your PC) may choose to drop certain packets if its not able to meet the bandwidth requirement (maybe busy doing other stuff, or the bus is too busy with other data).
> However, this does not mean there's no possibility of error checking. If a CRC is transmitted along with the packet, the device can perform an error check on its own. Whether that is of consequence is another issue. Since the device won't re-request the frame from the host, it can just drop the packet.
> So as you said, the tolerance for voltage is pretty high, so usually, the question is whether all packets are transferred reliably by the host, received by the device and not dropped. Windows can use ASIO for example, to minimize latency and give direct access to the sound card, bypassing the kernel mixer.


 
   
  WASAPI should have the same effect as ASIO, right? Since it also bypasses Windows mixing.
  If I understood correctly, in audio  USB transfer it uses an Isochronous mode, which has no way to correct the error (even if it's detected as an error) since it won't request the packet again. So there's a chance we get pops and artifacts in songs played from a USB DAC due to the cable? 
  Also what's this I hear about a CRC-able DAC?


----------



## nicholars

Quote: 





drez said:


> I guess I'm stumped then - I cant really find a theoretical justification for the effect of USB cables on a DAC.
> 
> 
> 
> ...


 
   
  LOL so after about 3 pages of arguing and calling me and other people stupid cynics etc. You have now basically admitted that you are probably wrong and my explanation is actually a lot more likely. Maybe you should do some more research before calling people names and making yourself look silly.... Basically my comments were aimed at steering people away from spending extortionate amounts of money on scam USB cables. I was giving a more logical arguement then your subjective, psuedo science and random opinion based claims.


----------



## sridhar3

Quote: 





nicholars said:


> LOL so after about 3 pages of arguing and calling me and other people stupid cynics etc. You have now basically admitted that you are probably wrong and my explanation is actually a lot more likely. Maybe you should do some more research before calling people names and making yourself look silly.... Basically my comments were aimed at steering people away from spending extortionate amounts of money on scam USB cables. I was giving a more logical arguement then your subjective, psuedo science and random opinion based claims.


 
   
  You completely missed the point AGAIN.  And you're talking about Drez making himself look silly... Sweet irony.


----------



## Lorspeaker

The usbcable i bought from screwtech sounded cleaner deeper clearer than the stock usb...from the first min..err ...secs.
  Clear cut better. Be it on the centrance or hdp... there is no placebo or gazebo....my dog agreed wagging his tail.


----------



## sridhar3

Quote: 





lorspeaker said:


> screwtech


 
   
  I don't know where the hell you're buying your cables from, but it's a far more interesting place than where I'm buying my cables from.


----------



## nicholars

Quote: 





sridhar3 said:


> You completely missed the point AGAIN.  And you're talking about Drez making himself look silly... Sweet irony.


 
  How did I miss the point? I made a simple comment trying to stop people wasting money because those cable companies annoy me... He starts defending them based on psuedo science and random opinions... How did I miss the point?


----------



## drez

Quote: 





nicholars said:


> LOL so after about 3 pages of arguing and calling me and other people stupid cynics etc. You have now basically admitted that you are probably wrong and my explanation is actually a lot more likely. Maybe you should do some more research before calling people names and making yourself look silly.... Basically my comments were aimed at steering people away from spending extortionate amounts of money on scam USB cables. I was giving a more logical arguement then your subjective, psuedo science and random opinion based claims.


 
   
  Mate don't worry you had nothing to do with my last post and have made no contribution at all to this thread.  Other people who actually have more technical insight than me in the area of electronics have leaned in and provided information which I was not previously aware of.  I respect the opinion of other people who either A) have sufficient technical insight to give meaningful input or B) have personal experience in the said area and give honest input based on their experience.  Further I think you will find I have not called anyone a stupid cynic (I hope.)
   
  It is not in my personal interest to spend large tracts of time reading Electrical Engineering 101 texbooks in order to speculate about whether a particular audio technology will have audible effects.  I already have another career.  I do however occasionally read up on said topic in order to try to gain better understanding out of personal interest, and I think threads such as this are a great place for discussion to take place which can not only extend my own understanding but also serve as a body of knowledge for others to gain insight from.  I may however unintentionally overreact when people who think the little knowledge they have is an adequate basis from which to declare jihad on the audiophile community without any intention of increasing their insight nor the decency to acknowledge the limits to their insight. I apologise if I have done this, it is nothing personal.
   
  I think most people are wise enough to steer clear of spending huge amounts of money on audio cables - it simply odes not make sense when the differences are so small (or possibly imaginary) that the money is better spent on components that have proven audible benefits.
   
  Claiming that any anecdotal observations are resulting from cognitive bias is itself spewing pseudo science - it is making a hypothesis which has not yet been proven directly.  Absence of evidence is not evidence of absence.


----------



## nicholars

I have not declared "jihad" on the audiophile community at all...
   
  I am all for buying DAC's, Amplifiers, Speakers, Headphones etc.
   
  I was merely giving my opinion on why people perceive differences in USB cables... I have already researched this subject and come to the conclusion that it is highly unlikely that they make a difference to sound quality other than expectation bias.
   
  I was merely voicing this opinion as I find it annoying that companies such as wireworld and nordost etc. are making VAST amounts of money selling these things to people at EXTORTIONATE prices.
   
  I think that on the subject of USB CABLES that thje psychological perspective is VERY VALID....
   
  DAC's, Amplifiers, Speakers, Headphones etc. I completely agree that these components DO make a measurable difference to sound quality... I am talking about USB cables.
   
  Cognative bias is not "psuedo science" AT ALL it has been proven in HUNDREDS of studies... Jeez please research things before making blanket claims which are wrong.


----------



## sridhar3

Quote: 





nicholars said:


> How did I miss the point? I made a simple comment trying to stop people wasting money because those cable companies annoy me... He starts defending them based on psuedo science and random opinions... How did I miss the point?


 
   
  You missed the point because you simply made an assertion, rather than an evidence-based argument grounded in logic and theory.  You're no different from the hundreds of other people parroting the same crap over and over again, based on something they read on the forums.  It's fine to adopt the viewpoint of one side or the other and have your own opinion in a given argument, but Drez is an open-minded individual, and he was simply looking for a rational scientific explanation for why or why not his claim was grounded in reality.  If you're going to make a case to him, you need to back it with evidence, which was delivered in spades by other, more knowledgeable members.  You have made precisely zero scientific/intellectual contributions to this thread, and in no way have you demonstrated that your opinion is worth consideration.  Screaming that the earth is round one hundred times at the top of your lungs doesn't prove that the earth is round, it just proves that you think it is but you either lack the understanding or the evidence to present a convincing argument that it is.


----------



## liamstrain

Quote: 





drez said:


> Claiming that any anecdotal observations are resulting from cognitive bias is itself spewing pseudo science - it is making a hypothesis which has not yet been proven directly.  Absence of evidence is not evidence of absence.


 
   
  In science, the absence of evidence supports the null hypothesis. It is not "proof" I'll grant you, but when that continues to be the case in test after test the preponderance of the evidence begins to be clear. When anecdotal evidence disagrees with a mountain of objective data AND theory, the first place to look is for where there are flaws and biases in the subjective evidences, not at tossing out the objective information.


----------



## nicholars

Ok I admit that you are correct that I have not contributed much to this thread.... I am not spewing this stuff about all equipment though... only about USB cables because I find the companies charging extortionate prices irritating and wanted to voice my opinion (which is most probably correct) on this matter. I was hoping to discorage other people from wasting their money but then Drez started insulting me saying he waas going to block me blah blah. My opinion is just as valid even if it is from a psychological and not scientific viewpoint because lets face it I am blatantly right.... I also find people saying everything is placebo and expectation bias annoying for example "amplifiers or dacs are all the same" etc. They clearly are not all the same. But yes USB cables are most probably expectation bias causing any perceived changes... TBH that opinion regarding USB cables is just as valid as anything else.


----------



## drez

Cognitive bias is a valid hypothesis but it is just that - it is a mechanism which has been theorised to be responsible for behavior of subjects in previous experiments, and which may be posited as a possible explanation for other phenomenon.  AFAIK Cognitive bias explains the tendency for people to attribute properties or differences when they are not actually directly perceived.  In the case of USB cables cognitive bias can be posited as a hypothesis for people mistakenly attributing properties that they cannot reliably perceive.  It does not however directly disprove the possible audible effects of USB cables on a DAC as it is a hypothesis rather than evidence.
   
  I actually agree that it is highly unlikely from a theoretical standpoint that USB cables will make an audible difference, and the hypothesis that peoples subjective observations of differences are caused by expectation bias is a valid hypothesis.  It is perhaps one I have read a few too many times though.
   
  This however is not in agreement with my personal experience, which I cannot posit as conclusive evidence but which I personally also cannot disregard without conclusive evidence such as persistent negative DBT results.


----------



## drez

Quote: 





liamstrain said:


> In science, the absence of evidence supports the null hypothesis. It is not "proof" I'll grant you, but when that continues to be the case in test after test the preponderance of the evidence begins to be clear. When anecdotal evidence disagrees with a mountain of objective data AND theory, the first place to look is for where there are flaws and biases in the subjective evidences, not at tossing out the objective information.


 
   
  Personally I don't think that the validity of past research into effects of jitter on distortion, audibility of distortion etc and the possibility of USB cables havaing audible effects on the performance of a DAC are mutually exclusive.  As is typical with situations of cognitive dissonance I would instead posit that there it is possible that due to the wide variety of technologies, due to the numerous factors that make discerning audible differences difficult, that positive evidence is waiting to be found.
   
  This is however a hypothesis which is without any evidence and is without a theoretical basis, so from a scientific standpoint it is probably not so valid.
	

	
	
		
		

		
			




   
  I don't like this game - I am predestined to lose.
	

	
	
		
		

		
		
	


	




  I guess I am a romantic at heart lol.


----------



## Lorspeaker

Cables have often been my saving grace in this audio hobby...
  how often have i bought a can or an amp, and tot i made a "mistake"...
  then with a few switching of cables, i arrived at sonicbliss,
  and began to better appreciate my purchase.
  Its a very convenient tuning device...cables.
  Home science at work thru my ears.
  Logic takes a backseat.
  This is audiopleasure.


----------



## nicholars

Yes I agree that people who call everything expectation bias is highly annoying and is used far too much....
   
  I think DAC's, Amplifiers, speakers, headphones all definately have effects on the sound... POSSIBLY speaker cables and interconnects although personally I am on the side of "any well designed, decent quality, non faulty cable of the same material will probably sound the same"....
   
  With USB cables however I think it is a valid explanation of the perceived differences.
   
  TBH I don't think I would even be having this conversation if I did not feel genuinely annoyed by cable companies and the prices charged....
   
  If they were charging £20 for a USB cable then fair enough... It is better quality probably then a standard one and looks nicer.... But the prices charged... Hundreds, even thousands of pounds... Is just extortionate and a scam IMO. Especially with some publications (not mentioning any names) CLEARLY revieiwing these products and saying they have massive sound improvements etc. It is clearly a scam.


----------



## drez

I think the problem is that this thread is here to discuss the "why" not the "if" and as such presupposes that differences are at least perceived (even if incorrectly).
   
  As such even if someone claims to hear a difference they are usually unable to explain the "how" at least in terms of strictly supportable science.  On the other hand science offers the usual explanation that cognitive bias is at play.
   
  I think this thread is at it's most productive when probing the technological side of the equation and tends to get stuck on the question "why are differences heard?"  Where people, myself included, attempt to problematise scientific research and hypotheses with untested subjective observations which tends not to go down so well...


----------



## nicholars

Ok then fair enough I see your point there....
   
  My post was mainly made out of irritation at the prices charged and the obvious links between the publications and the cable companies which is a scam and genuinely annoys me.


----------



## drez

Quote: 





nicholars said:


> Yes I agree that people who call everything expectation bias is highly annoying and is used far too much....
> 
> I think DAC's, Amplifiers, speakers, headphones all definately have effects on the sound... POSSIBLY speaker cables and interconnects although personally I am on the side of "any well designed, decent quality, non faulty cable of the same material will probably sound the same"....
> 
> ...


 
   
  I think there is a culture in audiophile circles of grossly overstating casually perceived differences when in all likelihood the differences are either non existent or very small.  I think a lot of equipment has grossly inflated prices, not only cables, but cables tend to be controvertial because the overwhelming scientific research/theory is against them.


----------



## nicholars

And I think people are too quick to dismiss psychological explanations....
   
  People who report hardware which changes daily are maybe just people who are perceiving the same sound differently on different occasions for whatever reason.
   
  Anyway this is irrelevant to this thread now so I will leave you to continue the discussion.


----------



## Losingedge

What ever cable makes one happy. Personally i have never heard any differences.


----------



## nicholars

I bet the manufacturers of wireworld or audioquest cables are VERY happy.... Smiling all the way to the bank!


----------



## Lorspeaker

that wireworld powercord is the best cord ever connected into my system...kudos to the engineers there, if u happen to view this post. 
	

	
	
		
		

		
			




   
  okok...back to your scientific discourse..


----------



## drez

Quote: 





nicholars said:


> I bet the manufacturers of wireworld or audioquest cables are VERY happy.... Smiling all the way to the bank!


 
   
  I think we agree on this point


----------



## anetode

drez said:


> Well I would suggest you use some more advanced comprehesnsion skills in order to appraise the tone of Nicholar's posting.
> 
> I am very willing to note that my observations may be affected by cognitive bias, on the other hand many freshling objectivists are not willing to concede that they are merely regurgitating second or third hand opinion and are clearly not familiar with either the technical or scientific foundations of these viewpoints.  This is not constructive.




Sorry, let me put it this way: you seemed a tad too touchy on the subject. Likewise, if I was as touchy, I'd take some offense at your insinuation that I am not using advanced enough comprehension skills.



drez said:


> Cognitive bias is a valid hypothesis but it is just that - it is a mechanism which has been theorised to be responsible for behavior of subjects in previous experiments, and which may be posited as a possible explanation for other phenomenon. AFAIK Cognitive bias explains the tendency for people to attribute properties or differences when they are not actually directly perceived.




I think this might be the root of the misunderstanding. Cognitive bias is not a hypothetical factor - it is a necessary part of human cognition. All perception, thought and memory is influenced by various cognitive biases. Luckily we can learn to identify individual biases and attempt to compensate for them, but it is silly to say that one is simply not subject to a specific cognitive bias after being made aware of it.


----------



## LizardKing1

Quote: 





anetode said:


> Luckily we can learn to identify individual biases and attempt to compensate for them, but it is silly to say that one is simply not subject to a specific cognitive bias after being made aware of it.


 
   
  The question that moves us is: this difference that I am hearing, is it due to cognitive bias, or to some actual sonic difference? The bias is a constant, it's always there unless you're in blind testing conditions, no one argues that. But there's a chance (not with USB, but other cases) that beyond it there's also some physical difference.


----------



## anetode

That's where you get to the quagmire of correlating the measurements of some tenuously related physical parameters of the sound-making device to human response to and appraisal of that device. It's backwards, really. Kinda like worrying about potential causes of jitter rather than worrying about having an adequate PLL.


----------



## drez

Quote: 





anetode said:


> I think this might be the root of the misunderstanding. Cognitive bias is not a hypothetical factor - it is a necessary part of human cognition. All perception, thought and memory is influenced by various cognitive biases. Luckily we can learn to identify individual biases and attempt to compensate for them, but it is silly to say that one is simply not subject to a specific cognitive bias after being made aware of it.


 
   
  Good point, I never thought about it this way not having done much reading in psychology - if you do have any suggested reading I would greatly appreciate it as I quite interested in the field.  Do you think this is a matter that we have certain categories and theories with which we are trying to make sense of what our senses detect, and which will necessarily influence how we perceive things?
   
  WRT PLL and jitter what my theory is that there are actual bits being dropped somewhere as I have experimented with using upsampling at the computer side vs comparable upsampling at the DAC side (differences here could be down to the quality of the upsampling process and filters etc so this is just a vague theory) but I tended to prefer upsampling on the computer to upsampling further downstream.  It is a bit of a long shot but could this mean that bits are in fact being dropped before making it to the DAC rather than just differences in the upsampling processes?  
   
  Personally I have no idea how this is actually possible with an asynchronous USB receiver, the digital input receiver in my current DAC is DIR9001 as opposed to the more advanced WM8805 but for some reason I found the latter to sound too forward.  In the last DAC I was using where I could swap between DIR9001 and WM8805 but of course "forward" does not necessarily relate to any reliable technical performance criteria - I mean it could be that the DAC actually sounded subjectively better with the technically inferior performance of the DIR9001 chip for whatever reason.  I think what is difficult with this subject is A) that there is no agreement that there actually are differences and B) that there is no agreement as to what might be causing these differences, which doesn't really leave much chance for intelligent component selection...
   
  I mean maybe if I was using the WM8805 I would hear less differences between difference transport and cables etc?  I cant say for sure but I may try this out with my old DAC to try and make sense of this.


----------



## DaBomb77766

Quote: 





drez said:


> Good point, I never thought about it this way not having done much reading in psychology - if you do have any suggested reading I would greatly appreciate it as I quite interested in the field.  Do you think this is a matter that we have certain categories and theories with which we are trying to make sense of what our senses detect, and which will necessarily influence how we perceive things?
> 
> WRT PLL and jitter what my theory is that there are actual bits being dropped somewhere as I have experimented with using upsampling at the computer side vs comparable upsampling at the DAC side (differences here could be down to the quality of the upsampling process and filters etc so this is just a vague theory) but I tended to prefer upsampling on the computer to upsampling further downstream.  It is a bit of a long shot but could this mean that bits are in fact being dropped before making it to the DAC rather than just differences in the upsampling processes?


 
  Well the thing is, if just that were enough to actually cause bits to be dropped, let alone enough to cause an audible difference (keep in mind that dropping one or two bits here or there would be like missing say one sample, so like 1/44,000th of a second where the DAC has to guess what it was supposed to be), there's no way USB would be able to reach the full bandwidth it does with bulk data transfer - the actual amount of bandwidth being used for USB audio is pretty small in comparison.


----------



## Prog Rock Man

Can anyone show any causal link between how a USB cable is made, or what it is made of and sound quality?
   
  Can anyone show a causal link between how different USB cables conduct the electrical signal which contains the digital information required to reproduce sound and sound quality?
   
  By show I mean prove in a way that is testable, repeatable and verifiable.
   
  I have spent a lot of time looking and I cannot find anything that remotely approaches a causality.


----------



## anetode

drez said:


> Good point, I never thought about it this way not having done much reading in psychology - if you do have any suggested reading I would greatly appreciate it as I quite interested in the field.  Do you think this is a matter that we have certain categories and theories with which we are trying to make sense of what our senses detect, and which will necessarily influence how we perceive things?




For a quick tour of some of the wonderful ways our brains screw us over, there's "Inevitable Illusions" by Massimo Piattelli-Palmarini. For a more encyclopedic overview, see "Heuristics and Biases: The Psychology of Intuitive Judgment".

Being a bit cynical I'd also like to recommend Churchland's "Neurophilosophy" in order to pull back the curtain and show how fragile and tentative all cognition and theories thereof must be.


----------



## proton007

Quote: 





drez said:


> Good point, I never thought about it this way not having done much reading in psychology - if you do have any suggested reading I would greatly appreciate it as I quite interested in the field.  Do you think this is a matter that we have certain categories and theories with which we are trying to make sense of what our senses detect, and which will necessarily influence how we perceive things?
> 
> WRT PLL and jitter what my theory is that there are actual bits being dropped somewhere as I have experimented with using upsampling at the computer side vs comparable upsampling at the DAC side (differences here could be down to the quality of the upsampling process and filters etc so this is just a vague theory) but I tended to prefer upsampling on the computer to upsampling further downstream.  It is a bit of a long shot but could this mean that bits are in fact being dropped before making it to the DAC rather than just differences in the upsampling processes?
> 
> ...


 
   
  The effective resolution of the DACs differ (like 13 effective bits for 16bit DAC) based on the dynamic range they can produce, but thats a characteristic of the DAC. The USB will transfer the 16 bits over.


----------



## liamstrain

Quote: 





anetode said:


> Being a bit cynical I'd also like to recommend Churchland's "Neurophilosophy" in order to pull back the curtain and show how fragile and tentative all cognition and theories thereof must be.


 
   
  Very quickly dissolves into solipsism at that point... but fun stuff.


----------



## drez

Quote: 





anetode said:


> For a quick tour of some of the wonderful ways our brains screw us over, there's "Inevitable Illusions" by Massimo Piattelli-Palmarini. For a more encyclopedic overview, see "Heuristics and Biases: The Psychology of Intuitive Judgment".
> Being a bit cynical I'd also like to recommend Churchland's "Neurophilosophy" in order to pull back the curtain and show how fragile and tentative all cognition and theories thereof must be.


 
   
  Thanks for the references, I will definitely enjoy reading these.  Might have to renew my uni library membership depending what these cost to order ($50 yearly membership and having to bother travelling to the city vs poetential cost to purchase)


----------



## dexter3d

Here is a story from my experience. (Context: I'm not deaf and quite musical, can transcribe music by ear, have lots of live listening/playing experience, and don't use today's pop to test equipment). I was comparing two different DACs. You know, you read here on head-fi how ppl compare stuff and pretty much ALWAYS hear HUGE improvements in sound stage, frequency range, separation etc. So I started looking for these, and of course found something. In the beginning, it occurred to me that there were indeed certain differences between these two DACs, which were very different in terms of their generation and design principles. So I felt happy. This was because unpleasant uncertainty on which option was better fell off my back. I figured out which was better. I felt like I could come here and brag about the HUGE differences in pretty much every aspect.
   
  Just for the sake of interest, however, I asked my wife to help me to do a blind test. I had no doubts that it would confirm my findings. So I matched the volume (using spl measurement device and playing a single tone; I also did this in the non-blind experiment), put on my k701, and made sure that in no way I could see which source was playing. Surprise surprise: it was so hard to distinguish that half of my guesses were false. This finding was much less pleasant than finding HUGE differences. The only possible conclusion from this was that the 'differences' that I heard before had nothing to do with the actual sound. Visualization of the equipment made my brain do tricks on me, unconsciously. I did much more testing afterwards, returning to the same conclusion. Up to that point, I did not consider myself gullible. After that, so far as sound testing is concerned, I do not trust my ears anymore, unless they are accompanied by a blindfold.
   
  Do you know why they make cables look so nice and shiny, like in the flashing ads in this forum? 
   
  Some people swear by their cables. And now I can understand them, and sympathize.
   
  For example, there is a guy on this forum, called 'slim.a' if I remember correctly. I kinda used to read his reviews, which were very comprehensive and readable. But then I came across his review of different USB cables, where he claimed that he heard HUGE differences, and wrote extensively on these. Jeez, the test wasn't even blind. After that 'review', I don't do his reviews anymore.
   
  So from my experience, here are the few conclusions that I learned from this forum (not good for business, but here I go) and my experiments in this very subjective business:
   
  1) In hi-fi segment (this means disregarding realtek audio etc) stuff, if made correctly, doesn't make much of a difference (exception is transducers and if you go solid state->tube). Sometimes there is no difference at all. And its OK if there's none. Guess how many reviews you can find here where the conclusion is 'no difference'. There must always be something, otherwise its not interesting to write
   
  2) You can disregard any statement on 'differences' as false with 95% certainty if it is not backed up by careful (objective) volume level matching and blind testing. There might be also shortcuts to 'ignore', e.g. USB cable guys with 'the veil has been removed' or feelers of ultra spacious sound stages in techno and other boombastics.
   
  3) Consequently, according to my observations, around 90%, if not more, content on this forum (and in audio forums in general), so far as it relates to differences between different pieces of equipment, is rubbish generated by a combination of kids, fanboys, shills, and also honest people who tricked by their mind unconsciously promote someone else's business. Because of the latter we still have wars on earth. Critical thinking is our only salvation.
   
  4) The most important thing of all is music. Sometimes, cheap boombox can give much more pleasure and excitement than HD800, and its ok.


----------



## proton007

^^^ This. Thanks for your contribution.


----------



## drez

I think a lot probably comes down to the equipment being tested, at least that is how I would explain the observations I have been having (other than cognitive biasing.)  The USB to SPDIF converter I am using is a battery modified HiFace which has theoretical advantages in producing an SPDIF signal with less noise over the signal.  BUT the HiFace was designed to be plugged directly into computer, and this modified unit is connected via an USB cable.  The drivers for the HiFace are designed with a certain latency in mind for the USB connection, this latency being very small due to the fact that the original hiface is plugged directly into the computer without an USB cable.  The latest cable I have tested is all of 70mm in length and as short as possible, uses 26 AWG OCC copper for the fastest possible signal propagation and I have designed it without braided shielding and with a ground wire that sits away from the signal wires which are tightly bound in parallel , not that this is probably important.  What is important though is that this cable is designed to have the fastest possible signal propagation to be as close as possible to a direct USB connection.  The difference is by far the greatest I have heard between cables, yes large enough I am 100% confident that I can tell the difference in a blind test and I intend to do exactly this at the next local head-fi meet or even sooner.  I could not say with the same confidence that I could tell between other regular length cables no matter of price.
   
  I cant be certain that other converters or USB DAC's would respond similarly - it probably depends on the drivers, and buffer setup of the particular device.  Buffers are actually an interesting consideration as my limited understanding is larger buffers require greater processing time than smaller buffers, and if the buffer size is not adequate for the latency of the signal from the computer it will underrun and drop packets.  In fact one of the key features of the new HiFace 2 drivers is an adjustable buffer setting whereas the original hiface did not have this option.  I notice the difference most clearly on high definition material where the USB connection requires greater data throughput.  I do not think this has anything to do with jitter, only to do with latency and buffer sizes along with driver design.
   
  My thoughts overall are that yes USB cables can make a difference but ONLY if there is a confluence of factors relating to the hardware being used and material being streamed, in this case that the HiFace in my opinion is not designed to be used with a USB cable and did not have drivers that could adapt to the higher latency of the USB connection.  With the abundance of well designed modular USB receivers such as the XMOS system I think it is less and less likely that USB cables will be a factor in the performance of computer audio gear.


----------



## nicholars

I don't agree that all HIFI equipment is the same : I would say that DAC's, amplifiers etc. All have differences... Sometimes subtle sometimes more obvious.... From experience I have noticed differences.... Questionable areas would be cables and interconnects as well as the digital source, definately USB cables also.


----------



## tmars78

Quote: 





nicholars said:


> I don't agree that all HIFI equipment is the same : I would say that DAC's, amplifiers etc. All have differences... Sometimes subtle sometimes more obvious.... From experience I have noticed differences.... Questionable areas would be cables and interconnects as well as the digital source, definately USB cables also.


 
  I would agree that some HIFI equipment is different, but when built properly really shouldn't be different. If they are doing their job correctly they should send an unaltered signal to the speakers or headphones. I understand people like tubes and things of the sort, that doesn't make them inherently "better" though. I agree on the digital source thing. A $10,000 cd transport should sound no different than a $30 dvd player from Walmart as long as they are built properly. And seeing as companies have been making cd players for decades and dvd players for more than a decade I am pretty sure we have figured out how to make them properly. I understand better comes along every now and then, as in blu-ray, but that is a different type of format. Playing a cd on a cheap blu-ray player -vs- a top of the line cd transport should yield the exact same sound, if both are built properly.


----------



## nicholars

The thing people don't seem to understand when they make the "if all equipment was designed properly it would be the same and would be transparent/neutral" is that this defeats the whole point of manufacturers releasing different products with different sound signatures or different "house sound".. The manufacturers purposely dont make everything transparent and neutral and purposely colour the sound to make it "nice" or "smooth" or "energetic" etc etc.


----------



## proton007

Quote: 





nicholars said:


> I don't agree that all HIFI equipment is the same : I would say that DAC's, amplifiers etc. All have differences... Sometimes subtle sometimes more obvious.... From experience I have noticed differences.... Questionable areas would be cables and interconnects as well as the digital source, definately USB cables also.


 
   
  Of course, if you compare their specs and measurements on a graph, no two designs will be the same. The question is the magnitude of that difference, and whether it converts into any audible difference.


----------



## tmars78

Quote: 





nicholars said:


> The thing people don't seem to understand when they make the "if all equipment was designed properly it would be the same and would be transparent/neutral" is that this defeats the whole point of manufacturers releasing different products with different sound signatures or different "house sound".. The manufacturers purposely dont make everything transparent and neutral and purposely colour the sound to make it "nice" or "smooth" or "energetic" etc etc.


 
   
  That is all well and good, but then manufacturers shouldn't claim a superior product when and if in fact it isn't. That's my only beef. People saying you need to spend thousands, when you really don't.


----------



## nicholars

Hmm well some products might be superior for the target user...
   
  For example... User wants a refined sound which is not harsh = Buy an arcam
  OR
  User wants an energetic sound = Buy a Naim
   
  For the different target users / sound signatures they are superior.... Maybe not technically superior but they will sound "nicer" to different people depending what they want.
   
  Not everyone wants a completely neutral and transparent system because TBH that is not what sounds best to most people.


----------



## drez

It depends really - some DIY designs will set you back thousands just in parts alone even avoiding boutique capacitors etc.  I think the important consideration is application - if you are using an efficient headphone, an amplifier with low distortion at the power levels you will be using the headphone with, and maybe a decent amount of headroom to allow for dynamics will probably be enough.  As for DAC's there is significant variation beyond distortion figures  as to the different sound signatures and characteristics, usampling or NOS, digital input designs etc. that while any one design may have low distortion it may not be to your taste.  This does not mean that you need to spend 10 grand to buy a CD player (or vinyl) with awful jitter performance, hefty distortion and a token low pass filter, but for people with a lot of money and not much imagination this may seem like the "only" way to get  the performance you are after.
   
  To me the whole point of USB to SPDIF was to allow cheaper DAC's to catch up with CD players and more expensive DAC's with either media servers or well designed USB inputs, And at least in my own experience the purpose/intent of USB cables has been to extract more performance from cheaper USB transports, and at least with my own equipment I can say with absolute certainty that this has been effective, if possibly only because the design of the transport was flawed to begin with.
   
  But to be honest I don't think it is productive to do the whole "head in the sand" thing by not demoing gear that has no proven audible benefit, or likewise claiming that any piece of equipment is superior without justification, but justification is a very subjective topic.  This is probably getting a bit off topic though.


----------



## liamstrain

Quote: 





nicholars said:


> Not everyone wants a completely neutral and transparent system because TBH that is not what sounds best to most people.


 
   
  Then use eq or something... don't compromise the audio data (and yes, I say this knowing full well that I enjoy my tube amps - but CD transports, dacs, etc. should be invisible). Or for that matter - at least give us some standards from which to deviate before you start throwing house sound into it, so that those doing mastering have a target, and so that consumers know ahead of time what they are in for.


----------



## proton007

Quote: 





liamstrain said:


> Then use eq or something... don't compromise the audio data (and yes, I say this knowing full well that I enjoy my tube amps - but CD transports, dacs, etc. should be invisible). Or for that matter - at least give us some standards from which to deviate before you start throwing house sound into it, so that those doing mastering have a target, and so that consumers know ahead of time what they are in for.


 
  Agree.


----------



## tmars78

Quote: 





liamstrain said:


> Then use eq or something... don't compromise the audio data (and yes, I say this knowing full well that I enjoy my tube amps - but CD transports, dacs, etc. should be invisible). Or for that matter - at least give us some standards from which to deviate before you start throwing house sound into it, so that those doing mastering have a target, and so that consumers know ahead of time what they are in for.


 
  Agree 100%. Why spend thousands for something that could get the sound you want cheaply? That seems ridiculous to me. I'd rather spend that money on music or something else. If you have the money to throw around and want something because of the way it looks, the way it makes you feel by looking at it or listening to it, then so be it. But don't tell people they need to spend a ton of money for it, when in reality you don't. I don't think anyone here thinks anything of people who spend enormous amounts of money on something that makes them feel good. The problem lies when that person tells someone new to the hobby that their gear isn't good enough and they need to spend a ton of money to get great sound. 
   
  This hobby should be about getting good sound, at a decent price. But alas, audiophiles can be snobs and don't want the common man to believe he can achieve great sound at a fraction of the price. They take it as a slap in the face to tell them that a $30 dvd player is as good as a $10,000 cd transport. Not my fault building a perfect digital source isn't rocket science. If more people held manufacturers responsible for being shills(not all of them) this hobby could be enjoyed much more, IMO.


----------



## drez

Quote: 





liamstrain said:


> Then use eq or something... don't compromise the audio data (and yes, I say this knowing full well that I enjoy my tube amps - but CD transports, dacs, etc. should be invisible). Or for that matter - at least give us some standards from which to deviate before you start throwing house sound into it, so that those doing mastering have a target, and so that consumers know ahead of time what they are in for.


 
   
  I probably agree here but from a consumer standpoint is it better to buy say a $750 colored DAC paired with a $750 neutral amp (say Yulong D18 and their new balanced amplifier) or $750 on a completely transparent DAC and then $750+ on a tube amplifier with low enough distortion?
   
  [hope this makes sense now]


----------



## bellsprout

Quote:


nicholars said:


> The thing people don't seem to understand when they make the "if all equipment was designed properly it would be the same and would be transparent/neutral" is that this defeats the whole point of manufacturers releasing different products with different sound signatures or different "house sound".. The manufacturers purposely dont make everything transparent and neutral and purposely colour the sound to make it "nice" or "smooth" or "energetic" etc etc.


 
  this not only goes against the principle of hi-fi, but also puts consumers in an unenviable position when manufacturers can get away with peddling anything under the sun for any amount of money. it also creates the illusion that manufacturers are somehow "above" objective design, and while u can speculate all u want about whether they are, u can't even define "nice" or "smooth" or "energetic" let alone tie some engineering principle that makes equipment so.


----------



## liamstrain

Quote: 





drez said:


> I probably agree here but from a consumer standpoint is it more economical to buy say a $750 colored DAC paired with a $750 neutral amp (say Yulong D18 and their new balanced amplifier) or $750 on a completely transparent DAC and then $750+ on a tube amplifier with low enough distortion?


 
   
  Arbitrary numbers, but I'd go with the transparent DAC - at least that gives you the most flexibility downstream.


----------



## drez

Quote: 





bellsprout said:


> Quote:
> this not only goes against the principle of hi-fi, but also puts consumers in an unenviable position when manufacturers can get away with peddling anything under the sun for any amount of money. it also creates the illusion that manufacturers are somehow "above" objective design, and while u can speculate all u want about whether they are, u can't even define "nice" or "smooth" or "energetic" let alone tie some engineering principle that makes equipment so.


 
   
  Welcome to late capitalism


----------



## nicholars

Whilst it sounds good in principle I have recently purchased an Arcam dac which supposedly smooths the high end a bit  and compared to the supposedly neutral Dacmagic it sounds a lot nicer... Although maybe this is just because the sound is better quality I don't know.


----------



## drez

Quote: 





nicholars said:


> Whilst it sounds good in principle I have recently purchased an Arcam dac which supposedly smooths the high end a bit  and compared to the supposedly neutral Dacmagic it sounds a lot nicer... Although maybe this is just because the sound is better quality I don't know.


 
   
  I guess it makes it hard to tell between sound signature differences and actual differences in fidelity in the case of coloured DAC's.  Even with neutral gear I have a hard enough time deciding what is "good" and what is "bad" qualities
	

	
	
		
		

		
			





  
   
  To be honest though I feel more embarrassed when I talk to a musician and they refer to basic musical concepts and I have no idea what they are talking about eg discussing whether a certain character from an opera is soprano or mezzo soprano
	

	
	
		
		

		
		
	


	




, not that this is really important to enjoying music rather than getting bogged down in technical details of the music itself.


----------



## liamstrain

Quote: 





nicholars said:


> Whilst it sounds good in principle I have recently purchased an Arcam dac which supposedly smooths the high end a bit  and compared to the supposedly neutral Dacmagic it sounds a lot nicer... Although maybe this is just because the sound is better quality I don't know.


 
   
  Does it? Did you ABX the two to see if you could reliably tell them apart? My experience with DACs in that range was extremely subtle at best.


----------



## LizardKing1

Quote: 





nicholars said:


> Hmm well some products might be superior for the target user...
> 
> For example... User wants a refined sound which is not harsh = Buy an arcam
> OR
> ...


 
   
   
  And it's fine to do that. What's wrong is saying those amplifiers or DACs are better.
  I realize my opinion isn't written in stone, but at least to me the difference between what I like and what is good is clear. I can love an amp that rolls-off on the highs and makes the bass 'boomier', whilst having a distorted square wave that makes the sound more 'forgiving'. But in no way is it ok to say this amp is superior to one with low distortion and flat FR, because it simply isn't. I can love it all I want, that doesn't make it good or bad.
  And furthermore, what's being repeated ad nauseum is that it's fine to not have a neutral sound, but it's simply more practical and cheap to simply use an EQ and a crossfeed plug-in than to buy an amp with these characteristics. The reason is that not only am I probably paying a lot for this amp, I can't turn off the bad measurements and get a flat sound, like I would with an equalizer.


----------



## nicholars

Yes I can conclusively say that the rdac is different to the dacmagic...
   
  The dacmagic sounds sharper and less refined and more digital sounding (less natural).... The bass on the dacmagic is maybe a bit better but overall the rdac DEFINATELY sounds more refined especially on low quality audio and speech.
   
  I understand that you may say "this is not objective all dacs should be transparent and neutral" etc etc. but I am telling you that it definately does sound different. I am a bit of a cynic in general regarding usb cables, speaker cables, interconnects etc. and before buying this DAC I was doubtful that it would make much/any difference but it definately does and I have switched between the two loads of times.
   
  Differences are :
   
  Dacmagic :
  Slightly warmer sound with more midbass, generally slightly better bass
  Sharper and less natural sounding (more of an edge to the sound)
  Emphasises the high end and sibilants more
  Good for electronic music but not so good for speech or some other genres
   
  Rdac :
  Clearer
  Smoother in the upper midrange / treble... Not so much rolled off as simply smoother and less digital / harsh sounding.
  More "spacey sound" with bigger soundstage
  More natural, softer sound
  Less emphasis on sibilants
  Bass is not quite as good... Sometimes it sounds better sometimes it sounds a bit boomy.
   
  Overall I prefer the rdac for its clearer and more refined presentation, especially for low quality sources such as freeview TV broadcasts because the dacmagic did not sound so great with low quality sources... I like the dacmagic for electronic music and still quite like it through my HD650 because they are so smooth with any source and the agressiveness of the dacmagic sounds quite good through them but for use with my speakers for music / films / TV the rdac is definately smoother. Some people may prefer the more agressive nature of the Dacmagic for some genres but overall I prefer the smoother rdac as an all rounder for TV, films, music etc.
   
  You are free to believe me or not but I can assure you that there definately is a difference which is not psychological.


----------



## Penarin

The WireWorld USB cables separate the power wires from the signal wires inside their cable. They claim that their "cables function over significantly longer runs than conventional USB cables."  And that they exceed the USB 2.0 specs.
   
  Which is kind of interesting.  Not that I need a 30 foot USB cable to go from my PC to my DAC...


----------



## nicholars

Yes but does that justify spending £40-£12000 on a USB cable for a 1m-3m length? (Yes wireworld do sell a USB cable for £12,000)
   
  Also is the power section even active if it is a non powered USB device?


----------



## McMaz

Quote: 





vandaven said:


> First off, this is a very entertaining thread.
> 
> As we all know, in most cases, the USB controller of the computer is not directly inside the USB port.
> 
> ...


 
  Your brand of logic has no place in this thread, although in the real world it is of great value.


----------



## nicholars

Yes that is what these companies such as wireworld etc make large amounts of money from.


----------



## ryder78

I am about to receive a Wireworld Ultraviolet USB 2.0m length USB cable as a bundle to the DAC that I am buying. I have to pay a small premium though I'm not sure if this cable would bring a subtle difference, if any.
   
  Any thoughts from those who have used this cable? If it doesn't make any difference then the cable will serve as a nice eye-candy with its striking color.


----------



## DaBomb77766

Quote: 





ryder78 said:


> I am about to receive a Wireworld Ultraviolet USB 2.0m length USB cable as a bundle to the DAC that I am buying. I have to pay a small premium though I'm not sure if this cable would bring a subtle difference, if any.
> 
> Any thoughts from those who have used this cable? If it doesn't make any difference then the cable will serve as a nice eye-candy with its striking color.


 
  Pretty sure this isn't the best place to ask that.  Might wanna check the actual cable forum.


----------



## LizardKing1

Quote: 





ryder78 said:


> I am about to receive a Wireworld Ultraviolet USB 2.0m length USB cable as a bundle to the DAC that I am buying. I have to pay a small premium though I'm not sure if this cable would bring a subtle difference, if any.
> 
> Any thoughts from those who have used this cable? If it doesn't make any difference then the cable will serve as a nice eye-candy with its striking color.


 
   
  You probably won't hear a difference. If you did it would be pretty obvious, like parts of a song skipping I think, and definitely not thing like a warmer sound. If you're going to get it anyway, it might be fun to try a blind test between that one and the cheapest shielded USB cable you had.


----------



## drez

Well not necessarily if the USB transport is asynchronous, the only times i have heard skips regardless of cable has been due to hardware interrupts causing the audio stream to cut out.
   
  But yeah I agree that most USB cables built to spec are not going to be all that different especially if they are the same length.  I mean I *think* I hear differences between various to spec USB cables such as warmth, treble and midrange smoothness, timing and imaging but generally these differences can be remarkably hard to pick in a double blind test.  The only differences I am 100% sure of are between normal length cables and my current 7cm cable where I am absolutely certain I or anyone else could puck the differences blind, and even then I can only say that this is the effect with my current USB transport, where others may very well show no difference at all.


----------



## LizardKing1

As far as I know, there aren't any asynchronous USB DACs. I think 6Moons' Wavelength DAC is asynchronous, but that's probably the only one. And even being asynchronous it doesn't necessarily mean it has error correction. I can't find anything saying for sure wether DACs have CRC, but even if they can recognize a packet as being badly distorted and unreliably readable, it won't get re-sent. So those pops and artifacts are to be expected in an unshielded cable.


----------



## uelover

Quote: 





lizardking1 said:


> As far as I know, *there aren't any asynchronous USB DACs*. I think 6Moons' Wavelength DAC is asynchronous, but that's probably the only one. And even being asynchronous it doesn't necessarily mean it has error correction. I can't find anything saying for sure wether DACs have CRC, but even if they can recognize a packet as being badly distorted and unreliably readable, it won't get re-sent. So those pops and artifacts are to be expected in an unshielded cable.


 
   
  There are many, I mean, really,_ many_, asynchronous USB DACs out there in the market.
   
  6Moons is an audio reviewer website though so I am not sure what you meant by *6Moons' Wavelength DAC*. They don't make DAC.


----------



## drez

I'm not sure if I understand this correctly either with regard to whether an asynchronous USB receiver can request dropped packets to be resent, and if so what amount of audio data there is on that packet?


----------



## LizardKing1

Quote: 





uelover said:


> There are many, I mean, really,_ many_, asynchronous USB DACs out there in the market.
> 
> 6Moons is an audio reviewer website though so I am not sure what you meant by *6Moons' Wavelength DAC*. They don't make DAC.


 
   
  Right you are. It's from Wavelength Audio and it's called The Brick. Here we go. I'm doing more reading on the subject and you're right, there are quite a few more. I think even with asynchronous streaming there's still no data re-sending, but now I can't be sure.


----------



## Carlos671

Within every industry there are products that cost more just for the sake of it.  If one manufacturer didn't make it someone else would.
   
  Some people have more money to spend than others


----------



## MaciekN

Yesterday I read in Hobby Hi-Fi magazine a short article titled "The truth about usb cables" or smth like that. I skipped the part where the reviewer described his listening test but in the second part he used an audiophile usb cable vs generic one to scan images, and audiophile cable gave a slightly larger file, although there was no difference to the eye.


----------



## liamstrain

Quote: 





maciekn said:


> in the second part he used an audiophile usb cable vs generic one to scan images, and audiophile cable gave a slightly larger file, although there was no difference to the eye.


 
   
  Way too many questions about process there to know what's going on. For instance, many scanners autofocus and adjust exposures before each and every scan (and unless you are very tech savvy, you may not know, or know how to disable that feature). Any adjustment to either feature (or quite a large number of other factors), could affect file size - especially if using a compressed file format.


----------



## MaciekN

I guess the idea was that audiophile cable preserves more information. IMO usb audio is about using communication protocol that allows handshakes between PC and usb chip and not uber expensive cables, though it was interesting to see what a hi-fi magaizne has to say 'bout this.


----------



## Prog Rock Man

Quote: 





maciekn said:


> Yesterday I read in Hobby Hi-Fi magazine a short article titled "The truth about usb cables" or smth like that. I skipped the part where the reviewer described his listening test but in the second part he used an audiophile usb cable vs generic one to scan images, and audiophile cable gave a slightly larger file, although there was no difference to the eye.


 
   
  That is typical of the tactic used. Did the article show any causal link to audibility of the difference? Did the article show a causal link to sound quality difference? Or did it just suggest a link by saying I heard a difference, I can measure a tiny difference, what I heard was caused by that difference?


----------



## kLevkoff

I always get a good laugh fro these discussions.....
   
  The output of a scanner is a DIGITAL FILE - which is a textbook example of the type of data that CANNOT, EVEN POSSIBLY be affected by the cable (as long as the cable isn't downright defective). When transferring a digital file between data devices (like a scanner and a computer), the file really is just numbers. The timing of the numbers is totally unimportant since they are simply being moved from one storage point to another. As long as the numbers arrive in good enough shape that the receiving device can read them correctly, then there cannot be any difference. Period! End! Anybody who claims otherwise really doesn't understand what's going on.
   
  A DAC has the potential to be affected by cables because the cable may affect the TIMING of the numbers (usually by adding or aggravating jitter), and the operation of a DAC IS sensitive to the timing of the incoming numbers. Now a reclocker (like the Audio-Gd DI or the Audiophilleo) is supposed to remove all original timing - by substituting the timing of its own clock (which is hopefully much better). Likewise, a DAC with a sample-rate-converter in it is supposed to re-do the clock, and replace the original clock with its own, which would make the quality of the timing of the original signal totally unimportant as well. Assuming that either device does its job correctly, then the cable cannot matter at all (the cable can matter to the extent that the device FAILS to do its job perfectly; and nothing is totally perfect).   
  
  HOWEVER, on a DAC that doesn't reclock the data it is quite reasonable to expect that, since the cable may cause jitter or other timing problems, and the DAC is still sensitive to those problems, the cable may indeed influence the sound.
   
  The answer isn't to get a better cable, though; the answer is to utilize something that eliminates the timing problems, and so make the cable unimportant (like a DAC with an ASRC, or a DI, or an asynch USB converter, or whatever).
   
  Keith


----------



## sridhar3

Quote: 





klevkoff said:


> the file really is just numbers.


 
   
http://en.wikipedia.org/wiki/Universal_Serial_Bus#Signaling
http://www.beyondlogic.org/usbnutshell/usb2.shtml#Electrical


----------



## kLevkoff

Yes, and no.
   
  Digital data is indeed really an analog waveform; and that fact causes all sorts of problems. The whole "trick" is to make it as much like pure digital data as possible. In the case of USB, and DACs, and s/PDIF, the data itself is just numbers. HOWEVER, the process of turning those numbers back into audio requires timing information - a clock. It is this timing information that suffers because of the difference between an ideal square wave and reality.... in almost all cases, the data itself can easily be read perfectly, but the clock cannot be recovered anywhere near "perfectly".
  Luckily for us, what the clock should be is pretty well known and easy to determine for a given signal; this means that we can "fix" or "regenerate" the clock. Now, with our perfect data, and our new and very high quality clock, we have everything we need to get back the original audio with high accuracy.
   
  We have three choices here: we can try to repair the original clock; we can figure out what the clock should be and create an entirely new and equivalent one; or we can create an entirely new and different clock and then use really fancy math to figure out the correct new numbers (based on the old numbers) that will give us the output we want. Of course, we can also choose "none of the above" and do the conversion with the buggered up original clock. If we do any of the first three, then the USB cable we use shouldn't make any difference whatsoever - except in our minds.
  The real sole exception to that is that, if we choose to fix the original clock, a better cable might get it to us in a little bit better shape, which might enable our limited ability to repair it to give us a better overall result.


----------



## kLevkoff

Doesn't that depend on which specs you read.... and which ones really matter?
   
  When we're talking about an analog signal, there are all sorts of variables, and different people place different priorities on each.
  When we're talking about digital data (like what comes out of a CD transport), it all becomes a lot simpler.
   
  What's on a CD is just a file with a list of numbers in it.
  There are only two "relevent" specifications.
  The first is whether the numbers themselves are correct (that one is a simple "yes or no").
  The other is how accurately the timing between the numbers is delivered (the timing is NOT recorded on the disc; it is re-created by the player itself).
   
  IF you're connecting your transport to something that re-clocks the data, like a DAC with a re-clocker, or you're ripping it to a PC server,
  then the ONLY thing that matters is the numbers. In that case, unless one or the other is defective, the digital output of a $30 player IS
  ABSOLUTELY the same as the output of a $30,000 "CD transport" - and anyone who says differently is pulling your leg.
  They both play the disc and give you the numbers that are there. Since the timing doesn't matter, the discussion is over.
  
  Since the timing isn't stored on the disc, then something, either the player of some clocking device, must re-create it.
  It seems to make very little sense to NOT re-clock the data at the DAC since, by doing it that way, you are pretty much deliberately
  making things so any defects in the transport or the cabling will make the sound worse.
  (Remember that it isn't even theoretically possible to somehow make it sound better than it would with a good clock and correct data.)
   
  Keith


----------



## drez

Thats fine in theory - and with most USB receivers nowadays use asynchronous transfer mode so there is no clock recovery at the USB receiver.  There is however a buffer and as far as I know some sort of FIFO process to make sure no bits are dropped.  Some better transports even have bitperfect audit capability to make sure there is nothing being lost.  The only difference I can see happening with an asynchronous USB interface is that if the USB cable or computer has high latency then a larger buffer might need to be used, which in turn requires more processing power etc. but as far as I know should still allow bitperfect output.  At worst if there is a huge latency spike then some bits might be dropped.  If you have a wireless card then this might happen about once every minute or so with Windows operating system.  Linux and Mac tend to have lower latency but it is still a good idea to disable wireless and other unnecessary processes to avoid other threads competing with the audio playback thread/s.
   
  The point of all these buffers and PLL filters etc is to reduce the jitter in the signal to ensure that a bitperfect accurately clocked signal reaches the DAC.  Ideally in theory you could have reclocking inside the DAC as well but this is very uncommon at least in the DAC's I have been looking at and most just use bitperfect filtering and clock recovery, so in the real world the transport does play an influence at least in theory as the transport clock is recovered by the DAC as far as i know.  Also in theory, at least with the latest USB transports from XMOS, Audiophilleo etc it should be possibly to use any decent USB cable and computer without running into problems.  Users of transports like the Audiophilleo tend to agree that the USB cable and computer software/hardware do not make a very noticeable difference.  Experiences with the XMOS USB transports seem to be pretty thin as this is a new design but it is becoming very popular, even HiFace use the XMOS now, and some XMOS transports have been compared favorably to the Audiophillo AP2.  So in the ideal world these new generation of USB transports should take whatever the computer/cable throws at them and still produce a high quality bitperfect SPDIF or I2S signal.
   
  Unfortunately though a lot of transports floating around use adaptive or older asyncrhonous USB receivers and drivers which in my own subjective experience with a modified HiFace are not 100% robust and show differences in computer hardware, software and cabling.  Similarly some DAC's have excellent digital inputs with or without reclocking and seem indifferent to the transport choice, but most do not seem to match this level of performance.  My guess is that the more powerful the USB receiver, the better it can manage larger buffer sizes without breaking a sweat.  So if you have a DAC with  very high quality and powerful USB input such as Anedio, Antelope, Calyx, PSAudio etc it is not very likely that USB or computer will play a significant influence on the system performance.  For less advanced DAC's choosing a modern XMOS or Audiophilleo USB transport should take most of the computer and USB out of the equation.
   
  In the real (or imaginary) world nothing is 100% certain, no system is 100% jitter immune, and there will be specific cases where software/hardware including USB will matter eg with older tech USB receivers and DAC's, very slow, noisy, poorly set-up or old computers or other particular circumstances.  I think a lot of the seeming explosion of USB cables on the market is a product of these older technologies still on the market (esp adaptive USB) as well as particular circustances, as well as of course paranoid tweakaholics using imperfect systems.  IMO the name calling and stubborn minded opposition between ardent objective and subjective thinkers, or rather beleivers and non-believers (yes science and philosophy tend to overlap and in many cases stand in for one-another) is really not constructive.  The fact that many from the objective camp have taken a particular attitude toward the "unscientific" sectors of the Audiophile industry and those who support it doesn't help either (not that this has cropped up recently in this discussion).  The difference in philosophy over what constitutes audio performance is 100% a matter of opinion - one side seems to insist (at least in particular cases) that audio performance is a purely objective matter, while the subjectively minded would insist that objective measurements are a sidenote, an alternative measurement rather than an overriding and exclusive measurement.  Equally the confusion that results when purely subjective and anecdotal impressions are used to qualify performance continues to create confusion about jitter, electrical noise and its effect on digital to analog converters.  In my own experience certain forms of jitter can actually improve the subjective quality of order by creating a darker, warmer and more forgiving audio reproduction.  Similarly the designer of Antelope DAC's has said in an interview that certain forms of jitter can improve the subjective audio quality of a DAC by hiding certain electrical shortcomings in DAC chips, or otherwise creating a subjectively " more natural" presentation.  The problem occurs when a particular tweak is tested and considered to improve performance and therefore posited to lower jitter even though on paper it can be shown to increase jitter and latency.  Another interesting phenomenon is that people with warmer/darker gear tend to chose correspondingly brighter or more analytical source and transport equipment, which equally does not always correlate to lower noise or jitter.
   
  It is only human to consider that the particular point of view one has is valid and all other's are not.  I am not saying that anyone in particular is exhibiting this point of view, I am speaking purely in an abstract and theoretical manner.  This in a sense is essential to being productive, once one decides on a certain course of action it is productive to follow through with this until the task is complete.  In the context of a dialogue or at the stage of evaluating possibile courses of action this is not productive as it may exclude certain possible course of action or inquiry which may be valid or fruitful such as considering component selection or setup.  I think in this dialogue it is good that we have people from different perspectives that can contribute to the discussion as long as the door is left open to perspectives outisde if not contradictory to that particular perspective.


----------



## justanut

Can't you simply have a buffer at the receiving end and take the transport out of the equation? So it won't matter if your USB cable's asynchronous, clocked accurately blah blah? I mean thats what Amarra does on my Mac... it takes the data sent to my external dac and back to it, stores it on its buffer, and plays back the optimal version?


----------



## drez

To risk repeating what has been said before, USB doesn't actually transmit the audio at 44.1 khz or whatever, this is apparently above the frequency that USB operates at. So the computer must send the music data in packages which the transport/DAC must then reconstruct into a real time stream of audio data. The difference between asynchronous and adaptive USB transfer modes is that in adaptive the computer controls the sending of the packets, and in asynchronous the transport/DAC controls the sending of the packets. In both of these transfer methods buffers are needed in the transport/DAC as well as in the computer to account for small variations in the rate at which data is fed to each stage. 

What gets complicated though is when you start talking about how changes in any of these hardware/software components might affect jitter of the audio stream being fed to the DAC chip when all these buffers are in the way to make sure no data is lost and that all the samples are kept in the right order. In theory a USB cable is a passive component so it should not contribute actively to any timing variations in the data. it can only affect the USB signal (which is not transmitted in real time) maybe by provinding better shielding, better phase characteristics, impedance control etc for the USB signal (or in many cases worse performance but people subjectively think it is better). If you look at things from a technical perspective you would not predict that the USB cable would be able to affect the sound quality in any meaningful way. But I would be a hypocrite if I were to say that I think this is the complete story as I use audiophile USB cables myself, just I wouldn't say that the make a major difference in my system, definitely not "night and day" or something I am confident I could tell in a blind test. I would also say that a lot of audiophile USB cables I have tested have been rubbish and appear to add jitter to the sound, make the sound warmer and more vague etc. Pleanty of people swear by Monoprice and Belkin or DIY cables.


----------



## Bostonears

drez said:


> USB doesn't actually transmit the audio at 44.1 khz or whatever, this is apparently above the frequency that USB operates at.


 
   
  44.1 kHz x 16 bits per sample is 705 kilobits per second, plus overhead for error correction/detection, packetization and transfer protocols over USB. I don't know the actual amount of overhead, but for the sake of discussion, let's say it doubles the amount of data. That would still require less than 1.5 megabits per second. USB 2.0 is specified to handle up to 480 megabits per second. For CD grade audio playback, USB frequency isn't a limiting factor


----------



## mikeaj

Quote: 





bostonears said:


> 44.1 kHz x 16 bits per sample is 705 kilobits per second, plus overhead for error correction/detection, packetization and transfer protocols over USB. I don't know the actual amount of overhead, but for the sake of discussion, let's say it doubles the amount of data. That would still require less than 1.5 megabits per second. USB 2.0 is specified to handle up to 480 megabits per second. For CD grade audio playback, USB frequency isn't a limiting factor


 
   
  Enjoying your music in mono?  I think you need to multiply by 2 somewhere in there.  
	

	
	
		
		

		
			




   
  That said, you're right, and I think somebody must have made some kind of typo or botched explanation.  I don't think it was meant that USB can't handle the data rate, but I can't tell what was meant either.


----------



## kr0gg

Quote: 





bostonears said:


> 44.1 kHz x 16 bits per sample is 705 kilobits per second, plus overhead for error correction/detection, packetization and transfer protocols over USB. I don't know the actual amount of overhead, but for the sake of discussion, let's say it doubles the amount of data. That would still require less than 1.5 megabits per second. USB 2.0 is specified to handle up to 480 megabits per second. For CD grade audio playback, USB frequency isn't a limiting factor


 
   
   
  frequency is measured in hertz
  usb frequency is 12mhz
   
  usb bandwidth.. well, that one's measured in bytes.
  and as far as i know nobody ever sad that usb bandwidth is it's limiting factor in case of audio.
   
  it's just like if we would be speaking about speed highways - it's usually not about their width, but about their quality that matters.


----------



## Bostonears

> Originally Posted by *kr0gg* /img/forum/go_quote.gif
> 
> as far as i know nobody ever sad that usb bandwidth is it's limiting factor in case of audio.


 
  The very post I was responding to was implying that USB bandwidth was a limiting factor for CD-level audio, although the poster didn't word it that way. I probably should have put the word "frequency" in quotes, as I used it in response to the poster's use of that word.
   


mikeaj said:


> Enjoying your music in mono?  I think you need to multiply by 2 somewhere in there.


 
  I've got a nice Beatles box set that way. 
	

	
	
		
		

		
		
	


	



  But for everything else, I did indeed miss that multiplier.


----------



## drez

bostonears said:


> The very post I was responding to was implying that USB bandwidth was a limiting factor for CD-level audio, although the poster didn't word it that way. I probably should have put the word "frequency" in quotes, as I used it in response to the poster's use of that word.
> 
> I've got a nice Beatles box set that way.
> But for everything else, I did indeed miss that multiplier.




Come to think of it I must have made a mistake there - I was under the impression that all USB audio uses bulk mode transfer, but if the USB operating frequency is 12 MHz then I don't see why this would need to be the case. My bad, I blame confusion from an earlier discussion.h34r:


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## AJHeadfi

Quote: 





bostonears said:


> The very post I was responding to was implying that USB bandwidth was a limiting factor for CD-level audio, although the poster didn't word it that way. I probably should have put the word "frequency" in quotes, as I used it in response to the poster's use of that word.
> 
> I've got a nice Beatles box set that way.
> 
> ...


 
   
  I think you got it right the first time. 44.1kHz is ~ 2 x 22040Hz stereo. So it's all good by my observations.
   
  Meanwhile back in looney land I ordered a Furutech iD30PA 30 pin to USB A for the HP-P1. I interested to see if it makes any discernable difference, better or worse, anything will do me. Then I'll decide what the future will be. Maybe it will charge and transfer data to my iPod _faster_!


----------



## AJHeadfi

Quote: 





ajheadfi said:


> I think you got it right the first time. 44.1kHz is ~ 2 x 22040Hz stereo. So it's all good by my observations.
> 
> Meanwhile back in looney land I ordered a Furutech iD30PA 30 pin to USB A for the HP-P1. I interested to see if it makes any discernable difference, better or worse, anything will do me. Then I'll decide what the future will be. Maybe it will charge and transfer data to my iPod _faster_!


 
   
  ...and yes, better transparency, a subtle improvement that grows on me. I don't know why, it's just the way it sounds. There is a mysterious weakness being overcome somewhere in the link between the iPod and the HP-P1 (my imagination! no, no).


----------



## bigshot

Perhaps your shoes will seem just a little bit shinier.


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## AJHeadfi

Quote: 





bigshot said:


> Perhaps your shoes will seem just a little bit shinier.


 
   
  Everything is just better now. Mind over matter.  
	

	
	
		
		

		
		
	


	



   
  I use the ADL iD-30PA on a HP-P1. The difference between stock and ADL could be compared to the kind difference between digital filter position 1 and 2. Scientific I know, but that's what it boils down to.


----------



## Hi Rez

Quote: 





ajheadfi said:


> ...and yes, better transparency, a subtle improvement that grows on me. I don't know why, it's just the way it sounds. There is a mysterious weakness being overcome somewhere in the link between the iPod and the HP-P1 (my imagination! no, no).


 
  I recently borrowed a couple of aftermarket USB cables to try with my Solo -dB.  Used them with my iPhone 4s and my Macbook Pro.  I too experience increased transparency along with better textures in cymbals and bass.  With the stock cable, the iPhone 4s > Solo combination was good, but IMO left something to be desired.   The music was much more engaging using the aftermarket cable - pretty satisfying actually.  The Macbook Pro > Solo with the stock cable performance was already a notch above that with the iPhone, yet I also heard a noticeable improvement using that combo with the aftermarket cable.
   
  As a curiosity, I asked two of my co-workers to do blind tests with the cables.  One is a cable believer, the other a complete skeptic.  They both correctly identified the stock versus aftermarket cables.  The skeptic left shaking his head in disbelief....
   
  I don't claim to understand why, but they can make a difference.  Probably somewhat equipment dependent.  I have a USB cable on order....


----------



## Hi Rez

Quote: 





bigshot said:


> Perhaps your shoes will seem just a little bit shinier.


 
  And my shoes do seem a bit shinier too!


----------



## noahbickart

I have a usb keyboard. I used to connect it to my computer with a stock usb cable. On a whim I decided to use this cable instead: 
  http://www.audioadvisor.com/prodinfo.asp?number=AQMUSBDIA%20.75
   
  It costs a mere $548 dollars, which, given that I have about $2000 in my computer, seems like a good deal.
   
  Wow! The difference in my typing is amazing!
  My nouns and adjectives agree with more precision!
  My verbs stand out with greater action, and my nouns are free from hash and jitter.
  The words I write have better flow and pace.
   
  Anyone who can't tell the difference must not have golden ears. A better usb cable makes anyone a better writer.


----------



## AJHeadfi

Quote: 





noahbickart said:


> I have a usb keyboard. I used to connect it to my computer with a stock usb cable. On a whim I decided to use this cable instead:
> http://www.audioadvisor.com/prodinfo.asp?number=AQMUSBDIA%20.75
> 
> It costs a mere $548 dollars, which, given that I have about $2000 in my computer, seems like a good deal.
> ...


 
   
  That cable is plain snake oil, to lure the unsuspecting. I thought it was obvious.


----------



## AKG240mkII

Quote: 





noahbickart said:


> I have a usb keyboard. I used to connect it to my computer with a stock usb cable. On a whim I decided to use this cable instead:
> http://www.audioadvisor.com/prodinfo.asp?number=AQMUSBDIA%20.75
> 
> It costs a mere $548 dollars, which, given that I have about $2000 in my computer, seems like a good deal.
> ...


 

 I can EASILY explain the Night-and-Day difference you are experiencing in your typing depending on the connection-type ..
  However, I must start by telling you that you have everything backwards !!!
   
  PS/2 keyboards function by IRQ's (Interrupt Requests) . When you press a key it is _immediately registered  _by the CPU, because there is actually a DIRECT electrical connection 
  between your keyboard and the CPU .
  USB-keyboards work, obviously, via the USB-protocol . USB works by 'polling' the bus every 1000ms or so .
  This is like the difference between 'Bit-perfect WASABI'  and the dreadful Windows-mixer !!
   
  OBVIOUSLY this is jitter-prone and a big fat USB-cable with sexy-looking sleeving has much lower jitter than 'satandart' El-Cheapo cables .
  If you switch to a Gold-USB cable it ads the benefit of your Love-letters sounding 'warmer' !!


----------



## LizardKing1

noahbickart said:


> I have a usb keyboard. I used to connect it to my computer with a stock usb cable. On a whim I decided to use this cable instead:
> http://www.audioadvisor.com/prodinfo.asp?number=AQMUSBDIA%20.75
> 
> It costs a mere $548 dollars, which, given that I have about $2000 in my computer, seems like a good deal.
> ...


 
   
  I got about 20 words in before the sarcasm hit me =) nicely done
  Quote: 





akg240mkii said:


> I can EASILY explain the Night-and-Day difference you are experiencing in your typing depending on the connection-type ..
> However, I must start by telling you that you have everything backwards !!!
> 
> PS/2 keyboards function by IRQ's (Interrupt Requests) . When you press a key it is _immediately registered  _by the CPU, because there is actually a DIRECT electrical connection
> ...


 
   
  Didn't you mean polling every 1ms? If you poll every 1000ms, that's every 1 second.


----------



## xnor

Afaik, the default refresh rate for PS/2 mice is 40 fps (25 ms), my USB mouse uses refresh rates up to 2000 fps (0.5 ms).
   
  Data to USB DACs is sent each millisecond. My mouse doesn't need a special USB cable and neither does any USB DAC.


----------



## nanaholic

Quote: 





xnor said:


> Afaik, the default refresh rate for PS/2 mice is 40 fps (25 ms), my USB mouse uses refresh rates up to 2000 fps (0.5 ms).
> 
> Data to USB DACs is sent each millisecond. My mouse doesn't need a special USB cable and neither does any USB DAC.


 
   
  Woah a new business idea just hit me, should sell these jitter-free exotic USB cables to gamers and claim that it reduces mouse and keyboard lag and increase aiming accuracy!


----------



## xnor

Well, spending money on an USB cable trying to decrease input lag is like spending money on power cords trying to reduce speaker distortion.


----------



## GSARider

Have always been skeptical of uber expensive usb cables, however the hifi mags rave about them constantly, going on about 'subtle' differences in sound - for the better of course....


----------



## nanaholic

You never know, get a few professional gamers to endorse it (I "feel" the difference I swear!) and you might get more than few dumb people buying them, not unlike having a few "golden ears" endorsing USB cables.


----------



## penmarker

Watch these and come back to me saying those expensive *digital *USB cables make a difference.
   





   




   




   
  Sorry to crush your hopes and dreams. I guess if any of you still feel like it made a difference then you're probably just defending your expensive assets.


----------



## xnor

Oh, how the banana assessment reminds me of hifi reviews ...


----------



## noahbickart

Quote: 





gsarider said:


> Have always been skeptical of uber expensive usb cables, however the hifi mags rave about them constantly, going on about 'subtle' differences in sound - for the better of course....


 
  And yet I bet you've never seen a full page glossy add for a High-End Cable Brand?
   
  Who is footing the bill for those reviews?


----------



## GSARider

I have seen full page ads for the cable folk here in the UK and having worked in publishing previously for ten years or so, I know the deals that go on and the editorial pressure that ca be applied. However I have an acquaintance who works for a cable brand who has categorically told me that HDMI & USB Cables are overpriced. The conversation came up when I was querying a £90 HDMI Cable (160-180 Dollars US) and he said that a decently made £10-£20 cable would be just as good.


----------



## DeadlyNeodymium

I'll just say what I think... past $10-15, you're wasting your money.  It's a freaking USB cable, it's not going to make a big difference.  Not at all.


----------



## USAudio

99 US cents: http://www.monoprice.com/products/product.asp?c_id=103&cp_id=10303&cs_id=1030301&p_id=5437&seq=1&format=2


----------



## AJHeadfi

Come on guys, that's not in the spirit of audiophile. Get your high-end USB cables cryo treated. 
	

	
	
		
		

		
		
	


	



   
  Mine has been through the alpha process.


----------

