# Emotiva A-100



## ld100

Has anyone seen new Emotiva A-100? I wonder how that will work for a headphone amp?


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## ld100

You guys notices there is a headphone jack now? Am I the only one interested in that thing?


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## cabate

Yes, the new Emotiva A-100 should make a very nice headphone amp with plenty of power!
 I just ordered one for $169 (the holiday sale just started)! I'll let you know how it sounds after I spend some time with it.
  
 Chris


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## ld100

What DAC are you planning to use?


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## vincedea

I want this but I have the mini a 100 still not sure what to do with it if I bought the upgraded one


Sent from my iPhone using Tapatalk


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## cabate

I'm using the Musical Fidelity MX-DAC.
  
 Chris


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## monkuboy

I received the A-100 a few days ago and like it very much.  It has no problem at all driving my Senn HD-650 and HD-800 and it has very good control over the sound. It's clean, clear and with very well-defined bass. 
  
 The amp comes with a couple of jumpers to put over the resistors that will then put the full amp output to the headphone jack. I tried this and didn't really any difference so I took the jumpers back off.  The amp is also dead silent even with the knob turned all the way up. My normal listening level is with the knob around 9:00 (drawback is there is no marker on the knob) and around 10:00 it is very loud (too loud for my tastes). 
  
 The amp has good build construction - it looks good and is very solid. I like the versatility of the volume knob plus it has an auto-play setting so you can trigger the amp either with a normal 1/8" trigger wire or by detecting an incoming source signal. And it has pass through RCA outputs.  All in all it's a great amp, especially for the price. 
  
 The amp replaced an Oppo HA-1. While the HA-1 is a marvelous piece of equipment, my main reason for replacing was I really didn't utilize all the features and functions of the HA-1 and it seemed to me to be too expensive for just using as a headphone amp so I took a chance on the A-100 and am very pleased.


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## ld100

Wil





monkuboy said:


> I received the A-100 a few days ago and like it very much.  It has no problem at all driving my Senn HD-650 and HD-800 and it has very good control over the sound. It's clean, clear and with very well-defined bass.
> 
> The amp comes with a couple of jumpers to put over the resistors that will then put the full amp output to the headphone jack. I tried this and didn't really any difference so I took the jumpers back off.  The amp is also dead silent even with the knob turned all the way up. My normal listening level is with the knob around 9:00 (drawback is there is no marker on the knob) and around 10:00 it is very loud (too loud for my tastes).
> 
> ...




Will unplugging headphones send signal to preouts? Will it work with powered monitors?


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## monkuboy

ld100 said:


> Wil
> Will unplugging headphones send signal to preouts? Will it work with powered monitors?


 
  
 The preouts are always live.  I haven't tested it but the manual says it just sends along whatever signal is input to the RCA input jacks. Therefore it should work with powered monitors. The A-100 is pretty versatile.
  
 Here's a link to the manual:
  
 http://emotiva.com/resources/manuals/BASX_A-100_User_Manual_v10.pdf


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## ld100

monkuboy said:


> The preouts are always live.  I haven't tested it but the manual says it just sends along whatever signal is input to the RCA input jacks. Therefore it should work with powered monitors. The A-100 is pretty versatile.
> 
> Here's a link to the manual:
> 
> http://emotiva.com/resources/manuals/BASX_A-100_User_Manual_v10.pdf




If headphones are in preouts should be off I think.


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## monkuboy

ld100 said:


> If headphones are in preouts should be off I think.


 
  
 I don't think so.  The speaker outputs are muted if the headphones are in, but the preouts are always live. The preout just gets passed the signal from the inputs then it is up to the device that receives that signal to control it.


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## ld100

You might be right. I need something that would have volume control for headphones and monitors...


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## chedda7

They are still on sale so I just ordered one.  Going to see how it compares to my Audio GD C-2.


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## CdnGrimlock

I just bought one of these amp to drive my HD-650 and HE-400i.
  
 So far I'm really impressed with it. Good separations, and dead silent when turned up and no signal is going through.


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## elwappo99

ld100 said:


> Has anyone seen new Emotiva A-100? I wonder how that will work for a headphone amp?


 
  
  
 Check out this thread:
  
 http://www.head-fi.org/t/629352/he-500-lcd2-d5000-dt770-sr80-on-a-speaker-amp-emotiva-mini-x-a-100-project
  
  
 I was the first to hook up the a100 to headphones. Emotiva adding a headphone jack to the front is definitely head-fi inspired.


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## canthearyou

I have the Gen2 that I modded and put a headphone jack in. I use it to power my HE-500. I absolutely love the pairing!


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## cavedave

I just got a A-100 all I can say this is a very nice amp. Can not tell you about the speaker out put part. I only bought it for a headphone amp to be used with Hifiman HE-400i and man does it do a wonderful job. Great headphone amp.


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## canthearyou

It works wonderfully for planar headphones. It doesn't work well for very sensitive cans, though. When I plugged my TH-X00 or SHP9500 I can hear a constant hiss. With that said I haven't heard anything better to power my HE-500's.


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## cavedave

I just got the Hifiman Edition X and they work really well with this amp in fact they sound fantastic and no hiss
at all.


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## gug42

canthearyou said:


> It works wonderfully for planar headphones. It doesn't work well for very sensitive cans, though. When I plugged my TH-X00 or SHP9500 I can hear a constant hiss. With that said I haven't heard anything better to power my HE-500's


 
  
 Well really new amp at a good price .... bad news about noise ...  I hate so mouch any noise in my headphone.
  
 Waiting for more review, because i can't send it back easly (I live in europe so ...  )


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## alpovs

canthearyou said:


> It works wonderfully for planar headphones. It doesn't work well for very sensitive cans, though. When I plugged my TH-X00 or SHP9500 I can hear a constant hiss. With that said I haven't heard anything better to power my HE-500's.


 

 Do you like the A-100 more than the Gustard H10 and the Matrix M-Stage HPA-3B with modded OpAmps, especially the Sparkos? I followed you in others threads.
  
 I have the HE-500 and I bought the new version of the Emotiva A-100. I tried it without and with the jumpers and liked it more full power (with the jumpers), probably because my DAC outputs only 1Vrms in line-out (OPPO HA-2SE). I also have the Schiit Magni 2 Uber.
  
 The thing is I find that the sound from the A-100 is less detailed than from the Magni 2 Uber. I went here to look for a better amp for my HE-500's and the Gustard H10 and the Matrix M-Stage HPA-3B attracted my attention. And you had and modded them both. And your latest post on this topic says that you liked the Emotiva the most. I am going in circles  There is a chance that my A-100 is not burned in enough as it didn't run long but I am not a big believer in burn-in of solid state amps.
  
 And have you ever heard Jotunheim with your HE-500's, balanced or SE?


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## canthearyou

alpovs said:


> Do you like the A-100 more than the Gustard H10 and the Matrix M-Stage HPA-3B with modded OpAmps, especially the Sparkos? I followed you in others threads.
> 
> I have the HE-500 and I bought the new version of the Emotiva A-100. I tried it without and with the jumpers and liked it more full power (with the jumpers), probably because my DAC outputs only 1Vrms in line-out (OPPO HA-2SE). I also have the Schiit Magni 2 Uber.
> 
> ...




I've heard numerous high-end set-ups at the few local Head-Fi meets. I have come back to the a100/HE-500 every time. It just sounds so effortless in its reproduction of music. It's not super sterile, not super bass, not the biggest soundstage, but very balanced. 
I really want to minimize the space used at my listening station. I'm trying to find a all in one solution that doesn't break the bank. I'm hoping the Gustard a20h will meet my needs.

The modded HPA3-B with the Sparkos is a very smooth presentation. It also has a lower noise floor than the a100. 

I'll say the a100 and HE-500 did sound less detailed at first. I even posted I believe in this very thread stating that. But once I spent some time with it I realized all the details are there, but not as forward as other amps tend to make them.


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## cavedave

I have been doing this for over 15 years and this combination is by far the best. And in fact the only one I listen to. The HE 400i also work with this amp but after the Edition X i no longer listen to them and gave them to my kid. I have tried the A-100 with the jumpers in place and did not care for with the HEX with out them the amp is complety silent and for me the best soild state I have heard. Considering the price and the price of most of whats out there a joke. I would much rather spend money on something else. Not a lot of bells and wistles but as far as just plain good sound cant be beat. It does remind me of a real nice old reciever from the 70-80s with out the old and the big size and now a days the big price. Look how many guys who use to have all kinds of big headphone amps only have those big receivers now. And this answers the proble with out the size and age. Perfect in my thought. Just my 2 cents.. Oh side note ditch the little 18awg cord that comes with the amp and get something with at least 14awg or 12 makes a big diffrence is sounstage and details. That is for those of use who believe in such thigs all others need not bother.


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## canthearyou

I did remove the 220ohm resistors and replaced them with 32 ohm models. It sounds better and I still get a little ways to move the volume knob.


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## cavedave

An after thought to my post above. While the A-100 makes a great headphone amp the more I listen to the edition X I have come to the conculsion you can play them through any thing and they sound good. They may sound diffrent through diffrent amps but I have yet to find one they sound bad. So the amp is cool but alot of the cool has to be given to the headphones. Just dont want to mislead any one about this set up.


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## canthearyou

It also pairs very well with AKG K7XX.


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## Moochibond

Hi Guys,

 Anyone who owns this with HD 800 able to post impressions?
  
 Many thanks,
  
 Mooch


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## gregcss

cavedave said:


> Oh side note ditch the little 18awg cord that comes with the amp and get something with at least 14awg or 12


 
 Do you mean the thin power cable? If so, do you mind if I ask what you replaced it with?


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## cavedave

I got a Pangea AC-14 C-7 from Audio Advisor I think they still have them on sale. I got the 1 meter one makes a big diffrence and is really a cool looking cable. Way nice. I have other cables cost way more but for what ever reason this one works best on this amp. The other ones I have to use an adapter this Pangea one has a C7 end works perfect.


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## sikninjaskillz

I own both mini x and BAS X. BAS X replaced Gustard H10 w/Burson op v5 upgrade as my go to head amp. BAS X is more v shaped and dynamic than mini x, which I actually prefer with headphones. Emotiva told me they changed op amps and "made a few upgrades" when I asked about the sound signature change.


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## canthearyou

sikninjaskillz said:


> I own both mini x and a100. A100 replaced Gustard H10 w/Burson op v5 upgrade as my go to head amp. A100 is more v shaped and dynamic than mini x, which I actually prefer with headphones. Emotiva told me they changed op amps and "made a few upgrades" when I asked about the sound signature change.




Mini-x = a100. They are the same thing. Are you talking about the new model(BasX a100)?


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## sikninjaskillz

canthearyou said:


> Mini-x = a100. They are the same thing. Are you talking about the new model(BasX a100)?




Fixed.


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## canthearyou

Now I gotta try the new Basx model.


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## JBal4

I am kind of surprised that there has been almost no mention of the BasX TA-100. Speaker and headphone amp with dac that has usb, optical, coax, and bluetooth. Not sure but it sounds like the ta-100 has a separate headphone amp from the speaker amp(guessing because of the description and the different power specs between a100 and ta100). I have been eyeballing the ta100 for some time but still cant find very many reviews...


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## canthearyou

jbal4 said:


> I am kind of surprised that there has been almost no mention of the BasX TA-100. Speaker and headphone amp with dac that has usb, optical, coax, and bluetooth. Not sure but it sounds like the ta-100 has a separate headphone amp from the speaker amp(guessing because of the description and the different power specs between a100 and ta100). I have been eyeballing the ta100 for some time but still cant find very many reviews...




It's headphone output is miniscule compared to the A100.


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## JBal4

but for a couple bucks you could tap into the main power amp and add a second 1/4'' jack, then you would have high and low power output options running off two different amps


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## canthearyou

jbal4 said:


> but for a couple bucks you could tap into the main power amp and add a second 1/4'' jack, then you would have high and low power output options running off two different amps




Very true! Hmmmmmmm....


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## newtophones07

sikninjaskillz said:


> canthearyou said:
> 
> 
> > Mini-x = a100. They are the same thing. Are you talking about the new model(BasX a100)?
> ...




Okay call me confused?

Is the A100 the same as the BasX a100, and are these both the same as the "mini-x"????


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## sikninjaskillz

newtophones07 said:


> Okay call me confused?
> 
> Is the A100 the same as the BasX a100, and are these both the same as the "mini-x"????




A-100 came in 3 models for far. Mini-x gen 1 and 2, which gen 1 has silver plates and knob on front and gen 2 black. Not sure if any changes on the inside. And then bas-x which added headphone output, changed PCB layout, and changed op amp from tl072 to ne5532.


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## newtophones07

Ok now I get it. Thanks for clarifying


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## alpovs

sikninjaskillz said:


> And then bas-x which added headphone output, changed PCB layout, and changed op amp from tl072 to ne5532.


 
 Where is the OpAmp? Is there only one? I looked for OpAmps when I opened my latest version to install jumpers and couldn't find a single one. I removed the heatsink to look under it. So, I think I looked everywhere.
  
 P.S. I was surprised to see Emotiva branded capacitors.


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## sikninjaskillz

alpovs said:


> Where is the OpAmp? Is there only one? I looked for OpAmps when I opened my latest version to install jumpers and couldn't find a single one. I removed the heatsink to look under it. So, I think I looked everywhere.
> 
> 
> 
> ...


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## alpovs

sikninjaskillz said:


> alpovs said:
> 
> 
> > Where is the OpAmp? Is there only one? I looked for OpAmps when I opened my latest version to install jumpers and couldn't find a single one. I removed the heatsink to look under it. So, I think I looked everywhere.
> ...


 

 Did you find that the new version sounded worse? You only said "different".


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## sikninjaskillz

alpovs said:


> Did you find that the new version sounded worse? You only said "different".




Bas x sounds more v shaped and dynamic. And vocals sound more narrow in the center image. I love it with the headphones I use He-500 and Elear. Mini x sounds more natural with my focal 706 desktop speakers. The bas x makes them a little bright sometimes up close. I wouldn't say one is definitely better.


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## jwedwards75

I recently purchased the Emotiva A-100 amp and I am really impressed. It is easily better than my Schiit Magni 2 Uber or my JDS O2. Not. Even. Close. I use this amp with my HD 600s and 400is. However, I did try the Pangea AC-14 C-7 power cable. It sounded awful with this amp on first listen; I let it "burn in" for 30-35 hours, and the sound did not improve. With the Pangea, the Emotiva sounded like a veil had been placed over the sound on each of my 'phones. I was actually skeptical about whether a cable could make any difference whatsoever, and to my amazement I could not only hear a difference, but it was appreciably worse. What did improve the amp's sound was switching from Monoprice (and other generic) RCAs to Audioquest Evergreen cables These cables to my various dacs transformed a very good amp into an amazing one. I've heard details in my music that I didn't know where there before. Who knew that a cable could impact the sound so much?


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## canthearyou

jwedwards75 said:


> I recently purchased the Emotiva A-100 amp and I am really impressed. It is easily better than my Schiit Magni 2 Uber or my JDS O2. Not. Even. Close. I use this amp with my HD 600s and 400is. However, I did try the Pangea AC-14 C-7 power cable. It sounded awful with this amp on first listen; I let it "burn in" for 30-35 hours, and the sound did not improve. With the Pangea, the Emotiva sounded like a veil had been placed over the sound on each of my 'phones. I was actually skeptical about whether a cable could make any difference whatsoever, and to my amazement I could not only hear a difference, but it was appreciably worse. What did improve the amp's sound was switching from Monoprice (and other generic) RCAs to Audioquest Evergreen cables These cables to my various dacs transformed a very good amp into an amazing one. I've heard details in my music that I didn't know where there before. Who knew that a cable could impact the sound so much?




I have the stock power cable and the Pangea. I hear no difference between the two. Not sure how a power cable affects the sound. To each his own I guess.


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## jwedwards75

canthearyou said:


> I have the stock power cable and the Pangea. I hear no difference between the two. Not sure how a power cable affects the sound. To each his own I guess.


 
 Precisely my point, @canthearyou. A power cable shouldn't affect the sound, just as a change in RCA cable shouldn't make a noticeable difference. I have no explanation for the very noticeable impact of these cables.


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## canthearyou

I will argue that an analog cable(RCA) can make a difference. But that's for a different thread.


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## cavedave

jwedwards75 said:


> I recently purchased the Emotiva A-100 amp and I am really impressed. It is easily better than my Schiit Magni 2 Uber or my JDS O2. Not. Even. Close. I use this amp with my HD 600s and 400is. However, I did try the Pangea AC-14 C-7 power cable. It sounded awful with this amp on first listen; I let it "burn in" for 30-35 hours, and the sound did not improve. With the Pangea, the Emotiva sounded like a veil had been placed over the sound on each of my 'phones. I was actually skeptical about whether a cable could make any difference whatsoever, and to my amazement I could not only hear a difference, but it was appreciably worse. What did improve the amp's sound was switching from Monoprice (and other generic) RCAs to Audioquest Evergreen cables These cables to my various dacs transformed a very good amp into an amazing one. I've heard details in my music that I didn't know where there before. Who knew that a cable could impact the sound so much?




A better anaswer might have been the Pangea just did not work well with my system. I have used the Evergreen cables and found them to be a little dark sounding that is compared to their cinnamon even though for some aplactions I found the evergreen very nice for an entry level cable. My point is most stuff is not really good or bad it just may not work when paired with other pieces like dacs and cd players I treat all parts cables and all as if they were just as important if others did this they would get more enjoyment form thier over all system. So many times we throw the baby out with the bath water. I would hang on to the cable if you ever change dacs or cables you may be in for a suprise. Just some thoughts that may help.


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## jwedwards75

cavedave said:


> A better anaswer might have been the Pangea just did not work well with my system. I have used the Evergreen cables and found them to be a little dark sounding that is compared to their cinnamon even though for some aplactions I found the evergreen very nice for an entry level cable. My point is most stuff is not really good or bad it just may not work when paired with other pieces like dacs and cd players I treat all parts cables and all as if they were just as important if others did this they would get more enjoyment form thier over all system. So many times we throw the baby out with the bath water. I would hang on to the cable if you ever change dacs or cables you may be in for a suprise. Just some thoughts that may help.


 
 Cavedave, I certainly didn’t say that the Pangea is a bad power cable. In my previous post I said that this cable sounded appreciably worse than the stock cable on the Emotiva A-100. There are, of course, a number of variables at play—the specific dacs and headphones I used, for instance—but* my point was that, to my surprise, the power cable certainly impacted the sound of the Emotiva, and, to my ears, not in a positive way.*
  
 My corollary point was that the Evergreen RCA cables also changed the sound. This experience also surprised me—and that is something I wanted to share with others. I said that they improved the details (vs. Monoprice) I could discern from my HD600s and 400is on several dacs running into the Emotiva.
  
 The upshot of my post was that *I experienced power cables and RCAs impacting the sound of the Emotiva*. I did not expect to hear differences, and there is nothing scientific I know of that can explain my subjective experiences. Speaking to your point about synergy between equipment, *I think that the Pangea just does not pair up very well with the Emotiva*. Others might have a different experience.


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## cavedave

Point taken and agreed cables really do make a diffrence maybe not always a good one in every setup.
In my set up with the A-100 I am using the Edition x and have taylored every thing for this headphone.
The two you use are two of my favorites and very fine headphones just diffrent sound signatures therefore diffrent needs.
I have a bunch of power cables I tried and some were brighter then the pangea but to briight for my needs with my set up.
The Pangea works well with the A100 but as you find out it depends on the rest of your set up. Better not tell any body cables really do make a diffrence. Guess what so does where you set your equipment and what it is set on the list is endless and for most not even worth bringing up. You sound like you are on your way to some interesting findings.
In the process sorry about your wallet.


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## Andrew Rieger

Anyone compare the Basx A100 to a really high end headphone amp?


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## jwedwards75

Not sure what qualifies as a “really high end amp,” but in addition to having the Basx A100, I have an Audeze Deckard (and some lower end amps/dacs such as the Fiio x5, Schiit  M & M stack and O2/Odac). What I can tell you is that the Emotiva is extraordinary for the price. It drives my HD600s effortlessly, with wonderful clarity and extension. That being said, I don’t think it does a great job with low impedance cans. My 400is are very disappointing out of the Emotiva. They don’t sound any better than they do out of the Schiit stack. The Deckard, however, makes the Hifiman’s shine. But as wonderful as the Deckard is, I would be perfectly happy with the Emotiva if I were only driving high impedance headphones. The HD600s have a little more bass, a slightly thicker, richer sound out of the Deckard than the Emotiva, but the differences are marginal.


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## Guidostrunk

Did you happen to put the jumpers in for your 400i? Or put em on taps? 





jwedwards75 said:


> Not sure what qualifies as a “really high end amp,” but in addition to having the Basx A100, I have an Audeze Deckard (and some lower end amps/dacs such as the Fiio x5, Schiit  M & M stack and O2/Odac). What I can tell you is that the Emotiva is extraordinary for the price. It drives my HD600s effortlessly, with wonderful clarity and extension. That being said, I don’t think it does a great job with low impedance cans. My 400is are very disappointing out of the Emotiva. They don’t sound any better than they do out of the Schiit stack. The Deckard, however, makes the Hifiman’s shine. But as wonderful as the Deckard is, I would be perfectly happy with the Emotiva if I were only driving high impedance headphones. The HD600s have a little more bass, a slightly thicker, richer sound out of the Deckard than the Emotiva, but the differences are marginal.


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## jwedwards75

Guidostrunk said:


> Did you happen to put the jumpers in for your 400i? Or put em on taps?



I haven't tried the jumpers yet. That is something I might look to do. But right now I am loving my HD600s out of the Emotiva (bedroom setup), while I used the 400is with the exquisite Deckard (office).


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## jwedwards75 (May 15, 2017)

For those who might be interested, I tried the jumpers on the Emotiva this morning. As expected, there is not much play available on the volume pot. The HD600s do not sound especially different than they did without the jumpers; the 400is, however, are much improved. The Emotiva now has plenty of power to drive them.

Edit: I took the jumpers off. I found that the lack of play on the volume pot was an issue. There is some channel imbalance at the lower levels--and sometimes I don't want to listen to music at higher volumes. Sound is wonderful, however, when I turn the nob up. I decided to live with an excellent amp for the HD600s with the jumpers removed, while using the 400is strictly on my Audeze Deckard.


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## alphanumerix1

really considering this with my desktop setup > asus essence stx > a-100

any comment how it matches with the hd800?


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## xwing01

Would something like a AKG 553 pro be considered sensitive because i run those sometimes through my a-100 and i started to hear a Hiss from them a while after a got the amp that didn't happen when i got it so i'm wondering if my amp broke or my headphone i don't hear any hiss through my planars (this is with everything but power disconnected with it on but i don't hear this hiss if i'm going straight through my computer


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## JBal4

yea the akg k553(and the whole K55x line) are quite sensitive. What is your setup? The noise could be coming from some where further up your audio chain.


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## garbulky (Sep 8, 2017)

Y'all I bought this headphone amp and I couldn't believe it's selling for this price. It is a DREAM with the HD600s. The HD600's no longer feel dark or laid back. It simply came alive. Soundstage, resolution, unlimited dynamics. Oh and really low bass. Just insane really. Imo to beat this amp you are going to have to swing up to a Schiit Ragnarok. It has got huge amounts of power capability and I believe this is the reason the HD600's came alive. Lots of control.

I removed the jumper and absolutely heard a difference in dynamics - there was no smear. Just lightning quick transients. The first time I felt my headphone rig was not second class to my speaker rig. The jumper limtis the current output of the A-100 to prevent high sensitivity headphones from frying. Not a problem for the HD600. With the jumpers off, the A-100 pushes a godly 1300 mwatts in to 300 ohms. Doesn't sound like much? Check out how well other amps do at 300 ohms? You'll be lucky if they squeek out even a 100 mwatts. I've seen amp units that gasp out 14 mwatts at 300 ohms.
At lower impedances the A-100 will push 8.5 watts at 50 ohms more than enough to fry the headphones. Hence the jumpers to prevent over driving lower impedance headphones.
But with the HD600's....it's just a dream.

Speaker and DAC rig: (Axiom M80's fully balanced to Emotiva DC- to XPA-1 gen 2 monoblocks in class A mode + room treatments. With a source the Musiland Digital Times via BNC output. About a $4500 setup). I can't believe I'm saying this but it absolutely competed with this nice sounding speaker setup. In some aspects it did better as well.
I dare you to find anything close anywhere near that's price range.
Love it!





Along with the huge torroidal transformer, you will see that it has a ridiculous 20,000 mf of capacitance and that performance really shows bringing very low bass and extreme control to this set of headphones. The treble also really opened up. I am definitely hearing more air. The control allows everything to sound holographic with large amounts of layering. The fan is there for safety but it never activates.


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## Guidostrunk

I sold my Mjolnir 2 after spending a month with BasX A-100 , doing A/B comparisons. This amp is legit af! 





garbulky said:


> Y'all I bought this headphone amp and I couldn't believe it's selling for this price. It is a DREAM with the HD600s. The HD600's no longer feel dark or laid back. It simply came alive. Soundstage, resolution, unlimited dynamics. Oh and really low bass. Just insane really. Imo to beat this amp you are going to have to swing up to a Schiit Ragnarok. It has got huge amounts of power capability and I believe this is the reason the HD600's came alive. Lots of control.
> 
> I removed the jumper and absolutely heard a difference in dynamics - there was no smear. Just lightning quick transients. The first time I felt my headphone rig was not second class to my speaker rig. The jumper limtis the current output of the A-100 to prevent high sensitivity headphones from frying. Not a problem for the HD600. With the jumpers off, the A-100 pushes a godly 1300 mwatts in to 300 ohms. Doesn't sound like much? Check out how well other amps do at 300 ohms? You'll be lucky if they squeek out even a 100 mwatts. I've seen amp units that gasp out 14 mwatts at 300 ohms.
> At lower impedances the A-100 will push 8.5 watts at 50 ohms more than enough to fry the headphones. Hence the jumpers to prevent over driving lower impedance headphones.
> ...


----------



## unclebrudy

jwedwards75 said:


> For those who might be interested, I tried the jumpers on the Emotiva this morning. As expected, there is not much play available on the volume pot. The HD600s do not sound especially different than they did without the jumpers; the 400is, however, are much improved. The Emotiva now has plenty of power to drive them.
> 
> Edit: I took the jumpers off. I found that the lack of play on the volume pot was an issue. There is some channel imbalance at the lower levels--and sometimes I don't want to listen to music at higher volumes. Sound is wonderful, however, when I turn the nob up. I decided to live with an excellent amp for the HD600s with the jumpers removed, while using the 400is strictly on my Audeze Deckard.


I know you posted this a while back, and I read the followup post regarding jumpers - I'm gathering intel on this amp and was wondering if you don't mind elaborating on why the 400i and it didn't synergize too well? Thanks!


----------



## Guidostrunk

From what I gathered from his post. It was the fact that the hd600 didn't work well with the a-100 with the jumpers in due to volume control, and without the jumpers, there's not enough juice to power the 400i, for the best SQ. So he's using the 400i with  a different amp to power them properly, and using the a-100(jumpers out) with the hd600 . That's how I read it. The a-100 is a beast of an amp with the jumpers in for planars.



unclebrudy said:


> I know you posted this a while back, and I read the followup post regarding jumpers - I'm gathering intel on this amp and was wondering if you don't mind elaborating on why the 400i and it didn't synergize too well? Thanks!


----------



## jwedwards75

Exactly @Guidostrunk. The a-100/400i combo is phenomenal with the jumpers in. Without the jumpers, the combo was mediocre. There just isn't enough juice to power the planars for my liking. When using my HD600s with the jumpers, the volume pot had limited play and there was a lot of channel imbalance on low volumes so as to make this combo a poor one in my estimation.


----------



## garbulky (Sep 9, 2017)

I guess I should have clarified regarding the volume control. The trick with this amp is to use the right match.

1. With the jumpers off the volume control works in the lower end of its range making it nearly unusable an effective volume control for my HD600's. So at the lower settings on the knob you will have channel imbalance due to the nature of the potentiometer. 
I have a DC-1 which has an analog type of a resistor ladder on a chip volume control. I reduce the volume on the DC-1 a little bit down from maximum (0db). Then I turn the volume control on the mini-x up from zero past the channel imbalance point. So for me it's something a bit more than a quarter of the way or 9 o clock. My DC-1 is turned down to something like -25. After that I simply control the volume using the DC-1's volume control - not the mini-x.
So long story short use the mini-x like a power amp - just for headphones - don't use its volume control other than to set it higher than the channel imbalance point. 

Use the volume control of the upstream DAC afterwards. This applies for using it with the jumper off. With the jumper on you can use the volume control fine.

2. With lower impedance headphones I would not take off the jumper. The noise floor will likely make itself heard. I'm also not sure if these are the best thigs for IEMS and stuff. IMO this is a high impedace headphones dream. Or the dream of headphones that needs large amounts of power.

Though that sounds daunting...it's really not. It does a very solid job - providing you are using it with the right headphones and the right gear.


----------



## thedesigner2011

You could also run a preamp in front of the A-100, keeping the A-100's dial at maybe 50% and using the preamp to get more volume control


----------



## javb06

It's really exciting to see they added a headphone output. I've been looking into purchasing passive bookshelf speakers and this seems like the perfect all in one solution for having speakers and headphones. Anyone thoughts on pairing the A-100 with an HE560?


----------



## Guidostrunk

Match made in heaven with the HE560. I connect directly to the speaker taps on the back of the amp. If you run through the jack on the front. Be sure to put the jumpers in first.

Cheers


javb06 said:


> It's really exciting to see they added a headphone output. I've been looking into purchasing passive bookshelf speakers and this seems like the perfect all in one solution for having speakers and headphones. Anyone thoughts on pairing the A-100 with an HE560?


----------



## garbulky

Still enjoying this star class amp with every listen. Everybody who has tried it with (the appropriate) headphones has loved the heck out of it so far.


----------



## CallmeEd

Zeos's Review.....


----------



## xXxDanXx (Oct 18, 2017)

cavedave said:


> I got a Pangea AC-14 C-7 from Audio Advisor I think they still have them on sale. I got the 1 meter one makes a big diffrence and is really a cool looking cable. Way nice. I have other cables cost way more but for what ever reason this one works best on this amp. The other ones I have to use an adapter this Pangea one has a C7 end works perfect.



Do you have any thoughts on a DIY bulk cables? I've been considering picking some bulk cable from DH Labs to get a better arrangement of my equipment from the power source to the unit. The BasX power cable is quite short. Considering this one at $8/ft: http://silversonic.com/products/bulk-wire-and-cable/bulk-power-cable/power-ac-power-cable/ would be a reasonable price. I haven't made a power cable before but I'd imagine it would be quicker than making custom PSU cables for a HTPC case or on par with networking cables. The connectors though can get quite pricey.



jwedwards75 said:


> I took the jumpers off. I found that the lack of play on the volume pot was an issue. There is some channel imbalance at the lower levels--and sometimes I don't want to listen to music at higher volumes. Sound is wonderful, however, when I turn the nob up. I decided to live with an excellent amp for the HD600s with the jumpers removed, while using the 400is strictly on my Audeze Deckard.



I would say that I was around 5-10% on my PC's master volume with the Emotiva all the way up with jumpers on through HD-600's; I can't remember if I had Tidal at 50% or 100% though. If your controlling volume through multiple sources the jumpers in can be managed at 300ohms but the risk with that is if your volume lags once through software while increasing volume, you could be blowing out your ears a couple seconds later.



garbulky said:


> The HD600's no longer feel dark or laid back. It simply came alive. Soundstage, resolution, unlimited dynamics. Oh and really low bass. Just insane really. Imo to beat this amp you are going to have to swing up to a Schiit Ragnarok. It has got huge amounts of power capability and I believe this is the reason the HD600's came alive. Lots of control.



From my experience with the similarly priced Schiit Asgard 2 and the Emotiva BasX through HD-600's, the Asgard 2 had much more powerful bass. The Asgard 2 was actually very fatiguing at times through the HD-600's and rolled the treble off losing detail in the highs. Comparing the Emotiva to the Asgard I feel like it's much more neutral between the lows, mids and highs which is more in line with my preferences because a simple EQ a preset that works for an artist's albums and I have my ideal sound arrangement which was not working for me on the Asgard 2. Although for some reason I think the Asgard 2's bass did amazing well for game trailers, it was the only thing I favored on the Asgard. But what I've learned from testing amps is the sound signature and details change greatly between headphones.

---------------

I'm curious to read if anyone A/B tested it to the Schiit Jotunheim.


----------



## ahmadfaizadnan

[QUOTE="xXxDanXx, post: 13792873, member: 480258"
I'm curious to read if anyone A/B tested it to the Schiit Jotunheim.[/QUOTE]

I am actually curious about this too. Has anyone tried both of them?


----------



## garbulky

jwedwards75 said:


> Precisely my point, @canthearyou. A power cable shouldn't affect the sound, just as a change in RCA cable shouldn't make a noticeable difference. I have no explanation for the very noticeable impact of these cables.


I am quite interested in your experience with the Pangea. Like you, I don't think cables should affect the sound. However with headphones things seem different. I replaced the stock HD600 cable with the stock HD650 cable and felt there was some improvement. Other people also report improvements with better cables like balanced XLR's and all that. 
So I'm open minded at least with regards to headphones. Please tell me what kind of improvements you noted. Do you think the short length of the cable had to do with it. 
Looking at my A-100 now, it's obvious its power cable is not really that great. I doubt it's anything but a small generic unit. 
The HD600 does have a beefy power supply when compared to other headphone amps not to mention its sizable capacitance. So I'm wondering if a better power cable would make differences.


----------



## jwedwards75

My experience with the Pangea on the A-100 was not a positive one. The cable adversely affected the sound quality of the A-100 for reasons I can’t explain. The stock cable of the amplifier is flimsy, but it does a much better job than the impressive looking Pangea.    

As the case is, I have an HD600 and I have also replaced the stock cable with the 650 cable. The difference in sound quality between stock and the 650, to my ears, is very negligible—and perhaps non-existent when I factor burn-in. The 650 cable, however, is better built than the 600, and the 650 cable is not very expensive. Worth the upgrade, I suppose, on build quality alone.

I should note that I have had a very positive experience with headphone cables in one instance. The Audio Sensibility cable I purchased for my Hifiman 400i and 560s made a considerable difference from stock offerings. Again, I can’t explain why. There is no scientific reason for the sonic differences that I am aware of.  I can only report the very noticeable improvements in clarity, dynamics, bass and soundstage with the Audio Sensibility cable. I was actually totally underwhelmed with the 400i on the stock cable, even after hundreds of hours of burn-in. With the Audio Sensibility cable, the 400i puts my very capable HD600 (with HD650 cable) to shame.

In the end, what I can say is that the synergy between the A-100 and the Pangea was poor. Very poor. I didn’t expect there to be any difference, let alone a degradation in quality, but there was. And I was so hoping for improvement… Headphone cables, to my ears, have made a difference at times. And power cables, yes, a difference has been noted. To reiterate, I don’t know why, I don’t know how.


----------



## cavedave

xXxDanXx said:


> Do you have any thoughts on a DIY bulk cables? I've been considering picking some bulk cable from DH Labs to get a better arrangement of my equipment from the power source to the unit. The BasX power cable is quite short. Considering this one at $8/ft: http://silversonic.com/products/bulk-wire-and-cable/bulk-power-cable/power-ac-power-cable/ would be a reasonable price. I haven't made a power cable before but I'd imagine it would be quicker than making custom PSU cables for a HTPC case or on par with networking cables. The connectors though can get quite pricey.    I dont use the pangea cable any longer switched it for a PS audio one with the Emotiva A100 and the Hifiman X by far best headphone listen to date for me. In fact only rig I have other then home stereo gave away or sold all others.
> 
> 
> 
> ...


----------



## cavedave

Kind of hard to read but my reply to the above about the Pangea power cord is I no longer use it with the Emotiva A100. I now use a PSAudio
cable and put the pagea on my TV. The Emotiva with the Hifiman X is by far the best rig I have heard and the only one I have and listen to.


----------



## garbulky

cavedave said:


> Kind of hard to read but my reply to the above about the Pangea power cord is I no longer use it with the Emotiva A100. I now use a PSAudio
> cable and put the pagea on my TV. The Emotiva with the Hifiman X is by far the best rig I have heard and the only one I have and listen to.


Do you find the PS audio power cable is better than the stock cable? Mind describing any differences and also what the cable is called?


----------



## cavedave

garbulky said:


> Do you find the PS audio power cable is better than the stock cable? Mind describing any differences and also what the cable is called?


The cable is a PS audio jewel not sure you can still buy them. To me yes it is diffrent then the stock one and much better. As far as diffrences i have not listened to the stock one in some time only know I never thought to much about it.


----------



## cavedave

I want to add that I also own a Creek 21 amp which also works really well with the Edition X. The Emotiva may not be an end it all amp but it is a good one and for the price hard to beat. Only wanting to be up front because you can drive the Edition X with about any thing and they sound great.


----------



## allhifi

cavedave said:


> I just got a A-100 all I can say this is a very nice amp. Can not tell you about the speaker out put part. I only bought it for a headphone amp to be used with Hifiman HE-400i and man does it do a wonderful job. Great headphone amp.



cavedave: Do you remain impressed with the basx A-100 Emotiva ? I recently purchased Hifimman 400i's and was considering the basX A-100 -for headphone listening -and a back-up main power if ever required.

Now that you no doubt have more hours (on both can's & amp), any additional thoughts/comments ?

Thanks,

 pj


----------



## allhifi

cavedave said:


> I got a Pangea AC-14 C-7 from Audio Advisor I think they still have them on sale. I got the 1 meter one makes a big diffrence and is really a cool looking cable. Way nice. I have other cables cost way more but for what ever reason this one works best on this amp. The other ones I have to use an adapter this Pangea one has a C7 end works perfect.



Interesting observation -Pangea power cord/great match. I'm not sure whether to consider Schiit Magni-3 or basX A-100 Emotiva (w/HFM 400i), the Emotiva clearly more substantial and flexible (use also as man power amp -back up), but SQ with headphones is most important. Any (further) thoughts ?

pj


----------



## allhifi

jwedwards75 said:


> I recently purchased the Emotiva A-100 amp and I am really impressed. It is easily better than my Schiit Magni 2 Uber or my JDS O2. Not. Even. Close. I use this amp with my HD 600s and 400is. However, I did try the Pangea AC-14 C-7 power cable. It sounded awful with this amp on first listen; I let it "burn in" for 30-35 hours, and the sound did not improve. With the Pangea, the Emotiva sounded like a veil had been placed over the sound on each of my 'phones. I was actually skeptical about whether a cable could make any difference whatsoever, and to my amazement I could not only hear a difference, but it was appreciably worse. What did improve the amp's sound was switching from Monoprice (and other generic) RCAs to Audioquest Evergreen cables These cables to my various dacs transformed a very good amp into an amazing one. I've heard details in my music that I didn't know where there before. Who knew that a cable could impact the sound so much?



_"Who knew that a cable could impact the sound so much?  "_

Me -for the past 35-years. And, many/all of the better audio magazines -likely even longer.

Great you did the test/comparo; even better that you discovered the AC power cable "swap"  resulted in worse sound -also my experience with many after-market power cords. It appears (not surprisingly) AC power cords are highly system/component dependent.  (But, it matters not, simply "hijack" any old detachable power cord  (from anything) insert, and listen. There will be one that should have an immediate, positive impact.  

pj


----------



## allhifi

canthearyou said:


> I have the stock power cable and the Pangea. I hear no difference between the two. Not sure how a power cable affects the sound. To each his own I guess.



AC power cable choice/replacement often has a profound impact on SQ; likely due to its interaction with the audio components internal power supply itself. Meaning simply that once equipment "detached" the hard-wired power cord, this new "interface" introduced ample opportunity (for good and ill) to be introduced. 

pj


----------



## allhifi

jwedwards75 said:


> Precisely my point, @canthearyou. A power cable shouldn't affect the sound, just as a change in RCA cable shouldn't make a noticeable difference. I have no explanation for the very noticeable impact of these cables.



You (mercifully) are way-ahead of the curve/game by acknowledging the (oft-times) astonishing impact cable has on perceived sound quality. 
It's very real. It's demonstrable. Repeatable. 

With this understanding/knowledge, you can achieve higher fidelity (finesse, nuance, clarity/definition) within your favorite listening sources that will routinely, endlessly, elude those too smart to fall for such "snake-oil" ! (Remarkably, for these folks, it does not connect that the finest audio equipment manufacturer's, magazines and audiophiles have been enjoying/sampling such 'phenomena (if we can call it this) for decades, elevating the listening experience to new heights while others (based on 1920's research and arrogance) flounder about endlessly.  Go figure. lol

pj


----------



## allhifi

canthearyou said:


> I will argue that an analog cable(RCA) can make a difference. But that's for a different thread.



Not only can but does.

pj


----------



## allhifi

cavedave said:


> A better anaswer might have been the Pangea just did not work well with my system. I have used the Evergreen cables and found them to be a little dark sounding that is compared to their cinnamon even though for some aplactions I found the evergreen very nice for an entry level cable. My point is most stuff is not really good or bad it just may not work when paired with other pieces like dacs and cd players I treat all parts cables and all as if they were just as important if others did this they would get more enjoyment form thier over all system. So many times we throw the baby out with the bath water. I would hang on to the cable if you ever change dacs or cables you may be in for a suprise. Just some thoughts that may help.



Find, locate, purchase (beg, steal, trade-the-kids for )a pair of Acoustic Zen "Silver REF II"  interconnects; you'll have one of the best available period. For less money (and although not really in the same league) look for a pair of XLO Reference II's ($80-$100 used/1-M pair) or the newer REF III's (2009-current) to demonstrate how a piece-of-wire can make something sound so remarkably "fleshed-out" (in a open/detailed kind of way -not "dark" way).

pj


----------



## alpovs

Cable discussions are more appropriate in another thread.


----------



## allhifi (Nov 20, 2017)

Guidostrunk said:


> I sold my Mjolnir 2 after spending a month with BasX A-100 , doing A/B comparisons. This amp is legit af!



*garbulky said: ↑*

_"Y'all I bought this headphone amp and I couldn't believe it's selling for this price. It is a DREAM with the HD600s. The HD600's no longer feel dark or laid back. It simply came alive. Soundstage, resolution, unlimited dynamics. Oh and really low bass. Just insane really. Imo to beat this amp you are going to have to swing up to a Schiit Ragnarok. It has got huge amounts of power capability and I believe this is the reason the HD600's came alive. Lots of control._

_I removed the jumper and absolutely heard a difference in dynamics - there was no smear. Just lightning quick transients. The first time I felt my headphone rig was not second class to my speaker rig. The jumper limtis the current output of the A-100 to prevent high sensitivity headphones from frying. Not a problem for the HD600. With the jumpers off, the A-100 pushes a godly 1300 mwatts in to 300 ohms. Doesn't sound like much? Check out how well other amps do at 300 ohms? You'll be lucky if they squeek out even a 100 mwatts. I've seen amp units that gasp out 14 mwatts at 300 ohms.
At lower impedances the A-100 will push 8.5 watts at 50 ohms more than enough to fry the headphones. Hence the jumpers to prevent over driving lower impedance headphones.
But with the HD600's....it's just a dream."_

_...... I dare you to find anything close anywhere near that's price range.
Love it! "_

Great stuff ! Now that's some passion -and honesty.

For all others that question the equipment, cables and AC power preceding the HP's, re-read the above. 

I suggest to start with such a excellent (and economical) amplifier before either considering another HP or judging its performance until suitably driven. 

An entire new world awaits the intrepid explorer. Superb performance (sound quality) is never attained _without_ careful selection of everything preceding the transducer. Everything. 

pj
P.S. Premium amplifier, headphone cable and clean AC power elevates performance to levels unattainable without fulfilling such considerations.


----------



## cavedave

allhifi said:


> cavedave: Do you remain impressed with the basx A-100 Emotiva ? I recently purchased Hifimman 400i's and was considering the basX A-100 -for headphone listening -and a back-up main power if ever required.
> 
> Now that you no doubt have more hours (on both can's & amp), any additional thoughts/comments ?
> 
> ...


The A-100 is a great headphone amp period and works with all kinds of headphones I for one see no need for any other


----------



## allhifi

Excellent ! Thank you.

 pj


----------



## Zadok

It's a shame that they don't make the A150 or the A300 this way. I wouldn't want to use the 100 as a speaker amp, but it feels wasteful to buy an Emotiva amp for headphones separately from the speakers.


----------



## allhifi

cabate said:


> Yes, the new Emotiva A-100 should make a very nice headphone amp with plenty of power!
> I just ordered one for $169 (the holiday sale just started)! I'll let you know how it sounds after I spend some time with it.
> 
> Chris



 Oh man, you lucked out ($169.00) ! Incredible. Even at $229. that's a really nice amplifier. 

Do you know by chance if it uses bi-polar transistors for the output stage ?

pj


----------



## allhifi

CdnGrimlock said:


> I just bought one of these amp to drive my HD-650 and HE-400i.
> 
> So far I'm really impressed with it. Good separations, and dead silent when turned up and no signal is going through.



What makes it even more flexible (and better) is that you have the option of Fixed/Variable Jacks in the back; The Fixed enabling volume control by the much superior volume attenuator used in my Cambridge 840-E preamp !

pj


----------



## allhifi

Zadok said:


> It's a shame that they don't make the A150 or the A300 this way. I wouldn't want to use the 100 as a speaker amp, but it feels wasteful to buy an Emotiva amp for headphones separately from the speakers.



I think they skewed it correctly; at those very, very reasonable prices, buy two/both (A-150/300 for main loudspeakers and the (by all accounts fantastic A-100 basX) for the can's. I will be picking up the A-100 basX for my HPs', and although I doubt it will outshine my CA-2100 (Classe), it sure is nice to have a back-up if ever required -or, come to think of it, send a second signal out to another room (second pair of speakers). I'm liking this thing more and more.

pj


----------



## garbulky

Interesting thing about the Basx A-100 - I found its sound quality to be surprisingly good as a speaker amp. I compared its predecessor - the very similar mini-x a-100 to a Crown XLS driving my axiom m80 in a very large living room. The Axioms caused the crowns to sound shouty and bass shy with a mid range scoop- they weren't able to keep up with the changing swings of the speaker. The mini-x on the other hand did not have those problems presenting a nice even tone. In terms of tone it was similar in sound to the much bigger XPA-2 - though the XPA-2 was obviously superior. Though we didn't crank the mini-x to incredibly loud volumes, we never felt it was lacking in volume. 

On the other hand, though lots of people like the A-300, I found it to be a thoroughly boring amp. One that never did anything wrong but also didn't do anything "great". 

What I keep bugging Emotiva to do is this. A-100 class A fully balanced monoblocks. The power they have on top is honestly a huge amount. So sacrifice some of that power to go in to a high bias class A similar to their XPA-1 gen 2. So say 35% of its current power output in class A. And do the monoblocks balanced. And that's it. If they did this and charged $600-$1000 for a pair they would pretty much dominate the high end market.


----------



## cabate

allhifi said:


> Oh man, you lucked out ($169.00) ! Incredible. Even at $229. that's a really nice amplifier.
> 
> Do you know by chance if it uses bi-polar transistors for the output stage ?
> 
> pj


Sorry, I don't. I'm sure Emotiva could answer your question.


----------



## allhifi (Nov 22, 2017)

allhifi said:


> Not only can but does.
> 
> pj





jwedwards75 said:


> Exactly @Guidostrunk. The a-100/400i combo is phenomenal with the jumpers in. Without the jumpers, the combo was mediocre. There just isn't enough juice to power the planars for my liking. When using my HD600s with the jumpers, the volume pot had limited play and there was a lot of channel imbalance on low volumes so as to make this combo a poor one in my estimation.



RE: HFM 400i: I have, finally, run-in my 400i's to the recommended (and beyond)  150-hours 'break-in' time.

What an improvement ! These things are absolutely delectable; a very linear (accurate), open, transparent, nuanced and textured performance I cold hope for. The LF resolution and the mid-band accuracy sets up an accurate, engaging performance. It's simply stunning. And, at its price, a verifiable bargain.

Currently underpowered, I await the Emotiva A-100. Update to follow. But even without (a superior amplifier) there is much to savor with these sensational cans. Amazing.

 pj


----------



## Zoom25

Anyone try out Audeze's from this model?

I've used LCD-2, LCD-3, and HE-500 in the past with the first silver Mini-x. I wonder how it sounds now?


----------



## w0nx (Dec 11, 2017)

I love my A100, powering a pair of KEF q100s.  I recommend it highly; however, my left channel has recently gone out (or very low volume out of it).  Anyone have any experience with Emotiva's warranty service?


----------



## allhifi

w0nx said:


> I love my A100, powering a pair of KEF q100s.  I recommend it highly; however, my left channel has recently gone out (or very low volume out of it).  Anyone have any experience with Emotiva's warranty service?



Replace the (L-channel) fuse -even if a 'continuity' check says OK.

 pj


----------



## garbulky

w0nx said:


> I love my A100, powering a pair of KEF q100s.  I recommend it highly; however, my left channel has recently gone out (or very low volume out of it).  Anyone have any experience with Emotiva's warranty service?


I have. Turn around time is between 1 1/2 weeks to 3 weeks. They get you taken care of.


----------



## allhifi

CdnGrimlock said:


> I just bought one of these amp to drive my HD-650 and HE-400i.
> 
> So far I'm really impressed with it. Good separations, and dead silent when turned up and no signal is going through.



Grim: I'm looking for an amp for my (recently acquired) 400i's; how did it improve this excellent headphone ?

pj


----------



## garbulky (Dec 22, 2017)

allhifi said:


> Grim: I'm looking for an amp for my (recently acquired) 400i's; how did it improve this excellent headphone ?
> 
> pj


The Hifi man headphones are unusual because they are designed to use HUGE amounts of power when producing sound. We are talking 6 watts (6000 miliwatts!) @ 35 ohms from the specs of your headphones. So, this is the amp to easily deliver this power.  Very few amps come anywhere close to its power output. Do some googling and you'll see what I mean by the kind of power your headphones need. 

Luckily this Basx amp is one of the very few that can and pretty much the only one near the price it sells at.

It can put out 12 watts (12000 miliwatts) at 35 ohms. However make sure to bypass the resistors when you get it. If you don't, it is purposely limited to 0.2 watts or 200 milliwatts at 35 ohms  by the resistors (not enough). So for your Hifiman, bypass the resistors. Don't worry, you are supposed to and this is a feature of the amp. The instructions on how to do it are in the manual and requires no special tools.


----------



## canthearyou

garbulky said:


> The Hifi man headphones are unusual because they are designed to use HUGE amounts of power when producing sound. We are talking 6 watts (6000 miliwatts!) @ 35 ohms from the specs of your headphones. So, this is the amp to easily deliver this power.  Very few amps come anywhere close to its power output. Do some googling and you'll see what I mean by the kind of power your headphones need.
> 
> Luckily this Basx amp is one of the very few that can and pretty much the only one near the price it sells at.
> 
> It can put out 12 watts (12000 miliwatts) at 35 ohms. However make sure to bypass the resistors when you get it. If you don't, it is purposely limited to 0.2 watts or 200 milliwatts at 35 ohms  by the resistors (not enough). So for your Hifiman, bypass the resistors. Don't worry, you are supposed to and this is a feature of the amp. The instructions on how to do it are in the manual and requires no special tools.



Actually the 400i needs about 1 watt to reach 110dB.


----------



## allhifi

canthearyou said:


> Actually the 400i needs about 1 watt to reach 110dB.



(RE: Emotiva A-100 basX) It's the power reserve (low output impedance/high slew rate -and circuit bandwidth) above the 1,000 mW (to reach max spl) responsible for such 'dynamic' performance.

pj


----------



## allhifi

garbulky said:


> The Hifi man headphones are unusual because they are designed to use HUGE amounts of power when producing sound. We are talking 6 watts (6000 miliwatts!) @ 35 ohms from the specs of your headphones. So, this is the amp to easily deliver this power.  Very few amps come anywhere close to its power output. Do some googling and you'll see what I mean by the kind of power your headphones need.
> 
> Luckily this Basx amp is one of the very few that can and pretty much the only one near the price it sells at.
> 
> It can put out 12 watts (12000 miliwatts) at 35 ohms. However make sure to bypass the resistors when you get it. If you don't, it is purposely limited to 0.2 watts or 200 milliwatts at 35 ohms  by the resistors (not enough). So for your Hifiman, bypass the resistors. Don't worry, you are supposed to and this is a feature of the amp. The instructions on how to do it are in the manual and requires no special tools.



*Thanks* Grim: With that said, I'm confident the A-100's SQ is commensurate with its prodigious power output (into can's) ?

pj


----------



## canthearyou

allhifi said:


> (RE: Emotiva A-100 basX) It's the power reserve (low output impedance/high slew rate -and circuit bandwidth) above the 1,000 mW (to reach max spl) responsible for such 'dynamic' performance.
> 
> In my previous post I quoted the person stating the 400i needs 6 watts of power. That is very, very wrong. The drivers would probably burst into flames with 6W of power feed to them. And you don't need an additional 5 watts of power for dynamic headroom.
> 
> ...


----------



## allhifi

That may be true, but low output impedance and 'fast' circuits combine (with endless power reserves) to help define a can's true potential.

pj


----------



## kernel8888 (Dec 22, 2017)

So Im wanting to use this for a lcd-2, hd800, and he1000 v1, with a xda 2 dac on the front end

As far as I can tell, the power handling of the lcd-2 and he1000 would be fine for the basx bypassing resistors, and the high 600 ohm impedence of the hd800 should keep it safe as well?

any REAL LIFE danger of damaging these if I keep the basx volume at 50% or lower and control the volume with the xda 2?

Incredible pairing for headphones, and can be had for 400 +/- used all in.


----------



## garbulky

canthearyou said:


> Actually the 400i needs about 1 watt to reach 110dB.


 On paper my sennheiser hd 600 needs only a few mwats to get    Super loud. I have driven it with about 13 miliwAtts.  But this Amp is really all about control. It’s pretty much stomped on every other Amp I’ve tried


----------



## garbulky (Dec 23, 2017)

canthearyou said:


> 6 Watts


 I got the six watt figure from Amazon’s product page of this headphones


----------



## garbulky

kernel8888 said:


> So Im wanting to use this for a lcd-2, hd800, and he1000 v1, with a xda 2 dac on the front end
> 
> As far as I can tell, the power handling of the lcd-2 and he1000 would be fine for the basx bypassing resistors, and the high 600 ohm impedence of the hd800 should keep it safe as well?
> 
> ...


Yes this is right.  I know nothing about audeze but the hd800 would do it. You want to keep the a100 below 40% or less.  By the way I found the xda2 to be outdone by Emotiva’s dc1in terms of treble, resolution and dynamics


----------



## ra990

So glad I came across this amp while browsing. I just ordered it and plan on using it with the HE1000 V2s. Any DAC/preamp recommendations for it? Anybody else use this to drive their HE1000s? Do you use the normal mode or the direct drive with jumpers on?


----------



## iamjaymo (Jan 9, 2018)

Just ordered one. Figured hell, for $229, if it's not my flavor then just return it. But if it works out - this would be one hell of a deal on a speaker/headphone amp.

Plan to use it for HD-6XX and AKG K7XXs. Plus when everyone is gone at work will run my vintage JBLs with it. Might be the perfect office amp. We’ll see...


----------



## garbulky

ra990 said:


> So glad I came across this amp while browsing. I just ordered it and plan on using it with the HE1000 V2s. Any DAC/preamp recommendations for it? Anybody else use this to drive their HE1000s? Do you use the normal mode or the direct drive with jumpers on?


how did it go?


----------



## allhifi

iamjaymo said:


> Just ordered one. Figured hell, for $229, if it's not my flavor then just return it. But if it works out - this would be one hell of a deal on a speaker/headphone amp.
> 
> Plan to use it for HD-6XX and AKG K7XXs. Plus when everyone is gone at work will run my vintage JBLs with it. Might be the perfect office amp. We’ll see...



*Good *call. I'll bet you'll love it. (Using volume control caution, remove the "padding" resistors for the full 50 W/C (8-ohm), 12 W/C 32-ohm, 6 W/C (64-ohm). 3 W/C (128-ohm) etc., etc. from the headphone socket)

pj
_P.S. And who couldn't use a great little back-up amp (if it doesn't suit you -I have great doubt it won't) ?_


----------



## ra990

garbulky said:


> how did it go?



Couldn't tell you. I couldn't settle on a DAC w/preamp to go with it and the dimensions of the amp were a bit too large for my desk. Might consider it in the future. Watching this thread.


----------



## iamjaymo

Received the A-100 and got it setup and it’s been running for about 2 hrs. now from speakers only.  To say I am impressed would be a definite understatement. Right from the get go it sounded pretty damn good. 

I am coming from a $3100 British integrated amp at 110 wpc and, no, it’s not nearly as good as that, but this little Emotiva at $229 has no right to sound this good. Haven’t even tried headphones yet. More to come.


----------



## garbulky (Jan 12, 2018)

iamjaymo said:


> Received the A-100 and got it setup and it’s been running for about 2 hrs. now from speakers only.  To say I am impressed would be a definite understatement. Right from the get go it sounded pretty damn good.
> 
> I am coming from a $3100 British integrated amp at 110 wpc and, no, it’s not nearly as good as that, but this little Emotiva at $229 has no right to sound this good. Haven’t even tried headphones yet. More to come.


Oh ho ho ! Headphones is what it's for! You'll love it. With the Sennnheisers I reccomend bypassing the resistors. But you'll have to control the volume "upstream" of the amp to get the volume knob on the amp in to a reasonable position where channel imbalance doesn't happen. The difference is unfettered dynamics of any kind. Without bypassing the resistors they'll still sound great though. Try both! The AKG may do better without. But the Fostex may also benefit because it'll absorb 1800 mwatts of power. But you may have some noise with the fostex.


----------



## iamjaymo

Just hooked up the AKGs...NICE! Big difference, in a positive way, compared to running them thru the Audio-GD. The AKGs really came to life through the A-100. Really impressive. 

Taking my time and carefully listening. I can say I am mighty impressed so far.


----------



## iamjaymo

...CRAZY good with headphones! Wow


----------



## garbulky

iamjaymo said:


> ...CRAZY good with headphones! Wow


great!! Glad you are happy. When you get the chance try it bypassing the resistors. Have you tried the hd600 yet? That’s the one it will make the most difference on!


----------



## iamjaymo (Jan 12, 2018)

garbulky said:


> great!! Glad you are happy. When you get the chance try it bypassing the resistors. Have you tried the hd600 yet? That’s the one it will make the most difference on!



Don’t have the 600s, I have the 650s. Haven’t tried anything yet other than the AKGs and speakers. I’ll get there...got caught up in listening and enjoying a Police album without analyzing it. If it makes me forget it’s there it’s a good piece of gear!


----------



## ra990

Have you done the thing with the jumpers to send the full power to the headphones? What DAC are you using and I'm assuming it has a preamp that you're using to control the volume and setting the amp to the static volume to remove channel imbalance?

EDIT: Just found it listed in your signature.


----------



## garbulky

iamjaymo said:


> Don’t have the 600s, I have the 650s. Haven’t tried anything yet other than the AKGs and speakers. I’ll get there...got caught up in listening and enjoying a Police album without analyzing it. If it makes menforget it’s there it’s a good piece of gear!


Nice. Let us know


----------



## iamjaymo

ra990 said:


> Have you done the thing with the jumpers to send the full power to the headphones? What DAC are you using and I'm assuming it has a preamp that you're using to control the volume and setting the amp to the static volume to remove channel imbalance?
> 
> EDIT: Just found it listed in your signature.



Haven’t touched the jumpers yet - I’ll get there. Want to listen to it both ways and make an objective decision about it. Thing is, not sure I really need all that power for my 650s anyway.

The Cal Audio DAC is a tube DAC from the mid 90s...my fav DAC. I have compared it to many, many newer DACs and nothing I have heard beats it, regardless of price. Running an Amperex Bugle Boy in it and that gives a nice liquid sound.


----------



## garbulky

iamjaymo said:


> Haven’t touched the jumpers yet - I’ll get there. Want to listen to it both ways and make an objective decision about it. Thing is, not sure I really need all that power for my 650s anyway.
> 
> The Cal Audio DAC is a tube DAC from the mid 90s...my fav DAC. I have compared it to many, many newer DACs and nothing I have heard beats it, regardless of price. Running an Amperex Bugle Boy in it and that gives a nice liquid sound.


That's exactly what I said when I first got the A-100. It sounded so good with the HD600 and had so much power.  Try listening to Lorde's Team on Youtube. There is some serious impact. 
First I've heard of the Cal Audio DAC. Sounds interesting!


----------



## iamjaymo

garbulky said:


> That's exactly what I said when I first got the A-100. It sounded so good with the HD600 and had so much power.  Try listening to Lorde's Team on Youtube. There is some serious impact.
> First I've heard of the Cal Audio DAC. Sounds interesting!



Thanks, will check it out. You’ll be hard pressed to find much info on the Cal nowadays. They went out of business long ago. It doesn’t do any fancy DSD or even hi rez audio but it does one thing very, very well...16/44.1

No USB, just optical from my iMac to the Cal. About the only DAC I felt sounded better was the Luxman DA-06 at many multiples the cost. I feel some of the new Multibit DACs may be closer but I would need to do an A/B comparison of those. I will compare the ladder DAC in my R2R 11 soon with the Cal but for now just going to let the Emotiva burn in.


----------



## iamjaymo (Jan 14, 2018)

Update...

After some more burn-in...sat down to critically listen for a bit at some louder listening levels. My overall opinion hasn’t changed, this is one hell of an amp for the money. Definitely going to keep it. The A-100 is a perfect office rig for both headphones and speakers.

About the only negative I can hear is just a bit of compression when you really listen critically. Some jumbling together of sounds/instruments but the sound level was quite high when I heard this and it’s nothing that detracted from the overall music reproduction.

Bass is nice and tight, deep and not just a “thump” but has some texture to it. Treble is totally non-offensive and has a nice sparkle.

Doesn’t run hot at all and it looks great in the office. Well worth the purchase for sure.


----------



## garbulky

iamjaymo said:


> Update...
> 
> After some more burn-in...sat down to critically listen for a bit at some louder listening levels. My overall opinion hasn’t changed, this is one hell of an amp for the money. Definitely going to keep it. The A-100 is a perfect office rig for both headphones and speakers.
> 
> ...


Thanks for the update! I also agree with your bass comment. There is some serious extension and texture to the bass. 
Interesting you mentioned compression. Your the only other person I know who mentioned it. People called me crazy but I heard it too in the default mode with the resistors still engaged. (The resistors also increase the output impedance of the amp.) I hear it as a slight smushing together of some sounds, I guess compression in a way. Hard to call it compression due to the sheer grunt and power of the amp, but yeah. With the resistors bypassed, this issue goes away, though for me, the tone did change slightly and there is a teensy increase in background noise during total silence. But the lack of compression and resulting sound quality on my HD600 more than made up for it.


----------



## iamjaymo (Jan 14, 2018)

The compression, or blurring, was very slight but I heard it. It was a most complicated passage where I heard it in “Saint-Saens: Dance Macabre” off of Eiji Oue’s Mephisto & Co. album (FLAC). Not very many amps seem to sort it out totally. Like I said, it didn’t detract at all from the enjoyment of the piece and should not detract anyone from considering the A-100.


----------



## m usicguy

Im really looking into this amp.  For tv listening at night and music.  Does anyone have a review with Planar headphones.   If so?  Did bypassing the resistors make an improvement?

music guy


----------



## peepr

m usicguy said:


> Im really looking into this amp.  For tv listening at night and music.  Does anyone have a review with Planar headphones.   If so?  Did bypassing the resistors make an improvement?
> 
> music guy



I use this with my Hifiman HE-560 and they sound amazing. Straight from the taps.


----------



## iamjaymo (Jan 16, 2018)

Been listening today with my Fostex headphones, 25 ohm impedance and easy to drive, so I am using it with the resistors in play and the sound is big, powerful and smooth.  I can literally feel the power of the amp - I can't imagine what putting in the jumpers would be like. Don't know that I really need to as my all my cans are relatively easy to drive...’cept for the HD-6XX.


----------



## s2kPanda

I hate myself for finding out about this amp.


----------



## garbulky (Jan 17, 2018)

iamjaymo said:


> Been listening today with my Fostex headphones, 25 ohm impedance and easy to drive, so I am using it with the resistors in play and the sound is big, powerful and smooth.  I can literally feel the power of the amp - I can't imagine what putting in the jumpers would be like. Don't know that I really need to as my all my cans are relatively easy to drive...’cept for the HD-6XX.


You'll never know....  Think of it like this. You obviously like it. So explore the options it offers. You wont damage anything as long as you turn the volume down first. . Its just a few screws to take off the case. then you just push the jumpers in (with the power cable disconnected). You can listen with the case off to see if you like the result or not. And pull the jumpers out if you dont like it.
Instructions on pg15
https://emotiva.com/wp-content/uploads/2017/05/BASX_A-100_User_Manual_v10.pdf
Ive always been curious about Fostex. Ive heard good things.


----------



## m usicguy

@peepr 

How do you have your amp configured?   Jumpers installed. Or standard set up with 220 resistors.  I own he560 also.    

M usicguy


----------



## peepr

m usicguy said:


> @peepr
> 
> How do you have your amp configured?   Jumpers installed. Or standard set up with 220 resistors.  I own he560 also.
> 
> M usicguy



I have the original A-100 without the headphone jack so I run speaker tap adapters and run my 560 right from the taps. I have a picture somewhere I can post later.


----------



## lambdastorm

Had this amp a year ago, at that time I paired it up with LCD2 and didn't feel like its the best combo out there. Sure it has loads of power and sounds fairly laid back, but there's simply not enough improvement that I can justify keeping it over my NFB11. Now that I'm planning to get an ABYSS, is it worth re-purchasing? Just asking cuz most Abyss users out there isn't budget conscious while I'm super poor........


----------



## m usicguy

Well?

I got my A100 yesterday.  Listened to it for about a day and half.   I put the bypass jumpers.  Even with my Thx00.  It seems more clear and dynamic.  Its a very laid back sound.  MY q701 really come to life.  More to follow.  Just have to figure out how not to blow headphones up.   I have controllable sources.  So I think I might tape the volume knob on the A100 not to go above a certain limit.

M usicguy


----------



## kernel8888

Yea I was really nervous to put my k712 directly on, but I kept it quiet for night listening, and it was very impressive and lively for low level listening. My he500's sound great, but aren't as impressive at quiet levels to be honest, they like to rock out loud


----------



## m usicguy

Its me again,  M usicguy,

HOLY Schiit  Is this a dynamic MONSTER!!!


----------



## iamjaymo (Jan 18, 2018)

m usicguy said:


> Well?
> 
> I got my A100 yesterday.  Listened to it for about a day and half.   I put the bypass jumpers.  Even with my Thx00.  It seems more clear and dynamic.  Its a very laid back sound.  MY q701 really come to life.  More to follow.  Just have to figure out how not to blow headphones up.   I have controllable sources.  So I think I might tape the volume knob on the A100 not to go above a certain limit.
> 
> M usicguy



Hi, with the X00...do you have much play with the volume knob with the jumpers in??? Only 25 ohms for the X00s so you could blow them easily if not careful. Sorta scared to put the jumpers in


----------



## garbulky

iamjaymo said:


> Hi, with the X00...do you have much play with the volume knob with the jumpers in??? Only 25 ohms for the X00s so you could blow them easily if not careful. Sorta scared to put the jumpers in


Look at the specs. Its designed to take 1.8 watts and is 94 db sensitive. Id be careful but its designed to absorb a lot of power. 
https://www.massdrop.com/buy/fostex-x-massdrop-th-x00

The specs of the a100 are not linear with the resistors in. They dont decrease from low to high impedance. They are very low in output at 30 ohms at only 0.2 watts. (Your fostex are 25 ohms). The resistors add high impedance to something like 150 ohms output causing this weird behavior.
https://emotiva.com/product/a-100/


----------



## kernel8888

So I heard that the volume knob will determine how many WATTS are being sent to the headphones, so for simplicity sake if you've got 50wpc, and only have the volume up 10%, you're only sending 5 watts to the headphones?

is that correct?


----------



## garbulky

kernel8888 said:


> So I heard that the volume knob will determine how many WATTS are being sent to the headphones, so for simplicity sake if you've got 50wpc, and only have the volume up 10%, you're only sending 5 watts to the headphones?
> 
> is that correct?


No. Not linear


----------



## iamjaymo (Jan 18, 2018)

garbulky said:


> Look at the specs. Its designed to take 1.8 watts and is 94 db sensitive. Id be careful but its designed to absorb a lot of power.
> https://www.massdrop.com/buy/fostex-x-massdrop-th-x00
> 
> The specs of the a100 are not linear with the resistors in. They dont decrease from low to high impedance. They are very low in output at 30 ohms at only 0.2 watts. (Your fostex are 25 ohms). The resistors add high impedance to something like 150 ohms output causing this weird behavior.
> https://emotiva.com/product/a-100/



Makes sense...I'll grow a pair and just put the jumpers in.  I'll do it tomorrow... busy with other crap today.  Will advise how it goes.


----------



## m usicguy

The first thing I did was make a volume indicator on the knob.  So I know where it is.  Really emo?  I think being able to see where the volume is  important.  But no big deal

I use a variable source.  On my  DAP, i use the headphone out and my dac has a controllable volume out.  I turn both down.  Then i turn the amp up to 12 o clock and start turning up the source.  **Verify first your source is turned DOWN FIRST***

Then i find the happy spot between the two.  I actually get a lot of usable adjustment on the amp.  Right now im using it on my computer set up.  But when i put it on the tv,  I will tape the volume knob down so my wife doesn't touch it and use the volume on the dac/tv to feed the amp.  Im going to leave my jumpers in.  I think this really  opens the amp up.  

Ive been using my fostex thx00 on this amp with no problem.  I error on the safety side and keep my source turned down.  I can almost max out the knob on the amp.  Sounds really good.

For 229.00 dollars this is a steal!!!

M usicguy


----------



## s2kPanda (Jan 18, 2018)

Yall think it'd be safe to run Aeon Flows through these with the jumpers in? Seems like the headphones would blow up from looking at the insane amount of power to it.


----------



## m usicguy

Well when Fed Ex learns how to drive in the snow Ill know.  I ordered a pair and waiting for a week now due to snow.  Ill be running the open aeon on this amp.  Its going to be my wifes tv setup.  

If you have a controllable source you should be fine.  *************Do Not use a fixed output source!!!!!!!*********  If you do,  do not put the jumpers on and use the resistors instead and have a traditional headphone amp.  With the resistors its just like a normal amp. and do what you want.  It wont be as powerful and safer.   I think the resistor kinda flatten and compress the sound alittle.  Just my  2 cents.

Proceed with extreme caution!!!!!!!!!!!!!!

M usicguy


----------



## m usicguy

@peepr 
can u post a picture of your adapter

M usicguy


----------



## peepr

m usicguy said:


> @peepr
> can u post a picture of your adapter
> 
> M usicguy









https://www.amazon.com/gp/product/B0010CEIH8/ref=oh_aui_search_detailpage?ie=UTF8&psc=1 

https://www.amazon.com/gp/product/B000068O5D/ref=oh_aui_search_detailpage?ie=UTF8&psc=1


----------



## m usicguy

@peepr 
Holy crap i already own that.   Im such an idiot

M usicguy


----------



## m usicguy

I finally got my Aeon  Flows. 
Great headphone.   I have been running them fine on the A 100  I have a XDA-2 feeding the A 100.  The flows actually need some power  to sound good.  So My XDA2 is at -10 and the volume knob on the A 100 is at 1 o clock.  sounds pretty good and  nothing blew up!!!

M usicguy


----------



## s2kPanda

m usicguy said:


> I finally got my Aeon  Flows.
> Great headphone.   I have been running them fine on the A 100  I have a XDA-2 feeding the A 100.  The flows actually need some power  to sound good.  So My XDA2 is at -10 and the volume knob on the A 100 is at 1 o clock.  sounds pretty good and  nothing blew up!!!
> 
> M usicguy


Lol this is good to know. I'm going to use my R2R-11 in variable mode to feed the Emotiva when it comes in Monday.


----------



## opa1

I have the Emo Bass x A-100 coming today.  Going to try it out with PC, Jitterbug, Topping D30, Emo, HP's, Alpair 10p/Pensils. I've tried the Magni (first gen), Vali 2, Fulla 2.


----------



## Mightygrey

Hey guys, this definitely has my interest piqued. I'm considering getting one to stack with my Crack to switch between tubes/SS - sounds like it'd be a good match with my HE-5's. 

Question - are the RCA-outs a pass-through or is it a variable pre-out? Was thinking I could run my DAC into the A100 and straight back out to the Crack. If it isn't, perhaps a Schiit SYS could be an easy way to switch between the two, as well as attenuating volume upstream from the Emotiva if I decide to add the jumpers.


----------



## garbulky

Mightygrey said:


> Hey guys, this definitely has my interest piqued. I'm considering getting one to stack with my Crack to switch between tubes/SS - sounds like it'd be a good match with my HE-5's.
> 
> Question - are the RCA-outs a pass-through or is it a variable pre-out? Was thinking I could run my DAC into the A100 and straight back out to the Crack. If it isn't, perhaps a Schiit SYS could be an easy way to switch between the two, as well as attenuating volume upstream from the Emotiva if I decide to add the jumpers.


It's a full scale passthrough. It is not volume attenuated. So yes adding a Schiit Sys would be an easy way to switch. If you have a DAC with volume control upstream you can use that to control the volume instead of the Sys. When you add in the jumpers should have some sort of control upstream so you can use the mini-x as a power amp essentially. You could also get Emotiva's control freak. I've tried it and honestly didn't care for the weight or feel of it. It was too light weight and the knob was too easy to move. But it does do the job.


----------



## Mightygrey

garbulky said:


> It's a full scale passthrough. It is not volume attenuated. So yes adding a Schiit Sys would be an easy way to switch. If you have a DAC with volume control upstream you can use that to control the volume instead of the Sys. When you add in the jumpers should have some sort of control upstream so you can use the mini-x as a power amp essentially. You could also get Emotiva's control freak. I've tried it and honestly didn't care for the weight or feel of it. It was too light weight and the knob was too easy to move. But it does do the job.


OK gotcha - thanks for clarifying. I might just turn the volume waaaay down on my Mojo rather than setting it to line-out.


----------



## ra990

Damn, I couldn't resist giving this thing a try for my HE1000's. Also got a Schiit Saga to serve as a preamp where I plan on controlling volume after the jumpers go in. Going to use my idsd black label as DAC for now.


----------



## opa1

My Emo arrived and it's going back. The outputs to speakers are reversed. The HP section is correct. (left-Right).


----------



## m usicguy

before you send your amp back.  I can understand wanting the right speak and left speaker cable not over lapping.  If this is why you don't like the way its set up.   Just reverse you inputs.  Amp only knows whats input to the  left goes to the left side of the amp.  Right to right.  

I will say this,  To use the jumpers the amp prefers higher impedance headphones.  MY AEON flows 16 ohms, don't like the jumpers installed.  I went back to the resistors and its much better.   Withe my other headphones no problem and great power.  Like 47 ohm and higher.


----------



## garbulky

opa1 said:


> My Emo arrived and it's going back. The outputs to speakers are reversed. The HP section is correct. (left-Right).


You are thinking it's defective or something? It's not. Just reverse the speakers cables unless it's some kind of aesthetic thing for you that you can't stand.


----------



## garbulky

It should look like this. If it does then you have the correct amp.


----------



## iamjaymo (Jan 23, 2018)

Though not technically “defective” the speaker terminals aren’t suppose to he reversed. I get why you’d want to return it.

Have them fix it and sent it back to you. It’s frustrating but still a good amp.

EDIT: Maybe I mis-understand...is it wired wrong (reversed) internally or written wrong on the back?


----------



## opa1

iamjaymo said:


> Though not technically “defective” the speaker terminals aren’t suppose to he reversed. I get why you’d want to return it.
> 
> Have them fix it and sent it back to you. It’s frustrating but still a good amp.



Yes, I'm thinking the same thing.


----------



## garbulky (Jan 23, 2018)

iamjaymo said:


> Though not technically “defective” the speaker terminals aren’t suppose to he reversed. I get why you’d want to return it.
> 
> Have them fix it and sent it back to you. It’s frustrating but still a good amp.
> 
> EDIT: Maybe I mis-understand...is it wired wrong (reversed) internally or written wrong on the back?


If you look at the amp from the front, the left speaker jack is on your right side and the right speaker jack is on your left side. It's labelled and wired correctly. It's just not where you would expect them to be. Unless I'm reading the posters post wrong and he's saying it's actually wired incorrectly.


----------



## opa1

garbulky said:


> If you look at the amp from the front, the left speaker jack is on your right side and the right speaker jack is on your left side. It's labelled and wired correctly. It's just not where you would expect them to be. Unless I'm reading the posters post wrong and he's saying it's actually wired incorrectly.



Looks like your right!


----------



## iamjaymo

opa1 said:


> Looks like your right!



Yeah, that’s what I thought...that is was WIRED incorrectly.


----------



## opa1

iamjaymo said:


> Yeah, that’s what I thought...that is was WIRED incorrectly.


It's wired right. My mistake. I took it for granted that the right output posts would be on the right side.


----------



## s2kPanda

Got my Emo in today. My LCD-2Cs were impressive with just the R2R-11 amp, but the extra power with the jumpers in completely opened them up to a whole new sound. Love it. Hate that its so big I have to rearrange my desk tomorrow....


----------



## ra990

Just got mine today and hooked it up, put in the jumpers. I'm really surprised how far I can go on that volume dial with how much power this thing is putting out. I thought I'd pretty much be required to use a preamp for volume control due to channel imbalance at lower volume knob positions, but I can get up past 3 o'clock before I get scared, in fact I get about the same volume from it at the 3 o'clock position that I do with my ifi micro black label on turbo mode at the same position. The ifi puts out 4 watts. I guess the A-100 puts out most of it's power in the last little bit on the volume control? Anybody else have the same experience? I am driving HE1000, which are planar but not the most inefficient planars. I guess I was expecting way more power from it, not that I need it or anything.


----------



## s2kPanda

ra990 said:


> Just got mine today and hooked it up, put in the jumpers. I'm really surprised how far I can go on that volume dial with how much power this thing is putting out. I thought I'd pretty much be required to use a preamp for volume control due to channel imbalance at lower volume knob positions, but I can get up past 3 o'clock before I get scared, in fact I get about the same volume from it at the 3 o'clock position that I do with my ifi micro black label on turbo mode at the same position. The ifi puts out 4 watts. I guess the A-100 puts out most of it's power in the last little bit on the volume control? Anybody else have the same experience? I am driving HE1000, which are planar but not the most inefficient planars. I guess I was expecting way more power from it, not that I need it or anything.


Power isn't linear with this amp. You can have it at 10% on the knob and it'll still put out the power. Definitely get a variable source to control the volume from. Ended up returning mine the day after I got it since I was experience a lot of floor noise with the jumpers in, didn't experience it without them in but then it was an amp that was no where near the one on my R2R-11.


----------



## peepr

ra990 said:


> Just got mine today and hooked it up, put in the jumpers. I'm really surprised how far I can go on that volume.



Your dac must not put out much volume or voltage. I’m using this with a raspberry pi (volumio) and modi multibit and at full volume l can barely get to 8 on the dial. This is With HE-560.


----------



## ra990 (Jan 25, 2018)

peepr said:


> Your dac must not put out much volume or voltage. I’m using this with a raspberry pi (volumio) and modi multibit and at full volume l can barely get to 8 on the dial. This is With HE-560.


I did connect another source and it does seem to be putting out more power (might be putting out more than line level though, I'm driving it from the headphone out of the Apogee Groove) so you might be on to something. Still can comfortably past the half way point though.

This is a really transparent amp, I can hear the difference between two very good DACs easily.


----------



## garbulky

you may have accidentally adjusted volume or not put in the two jumpers!


----------



## lambdastorm

I was thinking about the same thing. This thing has WAY TOO MUCH disposable volume as a headphone amp. No headphone can handle more than 1/4 power it puts out.


----------



## ra990 (Jan 26, 2018)

garbulky said:


> you may have accidentally adjusted volume or not put in the two jumpers!



So I checked with the jumpers on and off, with the jumpers off I can go to max volume, with them on I can't go past the 2-3 o'clock position. So, they're working as they should. It's just that last bit between the 3-5 position is where the power my headphones can't handle resides. I also listen to my music slightly attenuated with replay gain so it's not as loud from the source as it could be.


----------



## IBJamon

So I am this close to just clicking buy on this thing.  I need a new desktop amp anyway, and my headphones could use a proper amp that is guaranteed to be good.

I was thinking, has anyone considered modding either the jumpers or the resistor to find some happy medium rather than either kinda wimpy vs. full bore?


----------



## garbulky (Jan 26, 2018)

IBJamon said:


> So I am this close to just clicking buy on this thing.  I need a new desktop amp anyway, and my headphones could use a proper amp that is guaranteed to be good.
> 
> I was thinking, has anyone considered modding either the jumpers or the resistor to find some happy medium rather than either kinda wimpy vs. full bore?


Just get it! it's fantastic! Well with the resistors engaged are definitely not wimpy. They still outclassed every amp I heard with it engaged. A lot of people don't even bother to stick in the jumpers to bypass the resistors. I listened to Team by Lorde on my HD600's with the resistors engaged. And man that thing was POUNDING when the drums kicked in. It just sounded even better with the jumpers in.  
If it wanted to be modded, I don't see that it could be very hard to do but I don't really know anything about it. The resistors are in a relatively easy spot to access. Shouldn't be too hard to change it out.
I could see that being useful. I imagine some designs would encounter the noise floor of the amp in direct drive mode. While it is non-existent with the resistors. So a slightly less potent resistor may be helpful to fine tune it to what you want. It will have to be a bulky resistor though to soak up all that juice.


----------



## IBJamon

Awesome.  I may get this (though temp out of stock at amazon, but I have gift cards) and get a D30 dac down the line when the funds refresh and be at a more or less endgame state for me.

I have emo amp in my HT so it will kinda match anyway. 

Has anyone rigged a good trigger off of usb or something?  I was thinking there must be a better way than the auto detect.  (My apologies for not reading all 12 pages yet.)


----------



## garbulky

IBJamon said:


> Awesome.  I may get this (though temp out of stock at amazon, but I have gift cards) and get a D30 dac down the line when the funds refresh and be at a more or less endgame state for me.
> 
> I have emo amp in my HT so it will kinda match anyway.
> 
> Has anyone rigged a good trigger off of usb or something?  I was thinking there must be a better way than the auto detect.  (My apologies for not reading all 12 pages yet.)


It may be easier for you to just get a smart plug from amazon like the $16 Eva logik smart plug. Hook the amp up to it and leave it turned on. If you have an echo dot which goes on sale for $30 on black friday and prime day you can just say things like "alexa turn off my amp". And the plug will turn off, turning off the amp. And the same for on. If you don't have an echo, you can just turn it off using your phone. 
However the amp consumes very little power. I would just leave it on the whole time. It allows an amp to reach its most stable operating temperature. I leave all my amps on the whole time except for my XPA-1 gen 2 simply because it consumes about 600 watts a pair in class A mode at idling. 

I went a slightly expensive route. 
The way I use my XPA-1 gen 2 to turn on and off is that I got an Emotiva ET-3. You can sometimes get it pretty cheap on their emporium section if you post a want to buy (WTB) ad on their forum.
The nice thing about it is it sends an on signal when the power is activated and an off signal when it loses power from the outlet. 
So I plugged that in to the smart plug and it worked the same way. But for something of low power like the mini-x, just attaching it to a smart plug would work fine. It won't hurt it to turn on and off that way.


----------



## IBJamon

Ordered.  I will see how much the auto thing bothers me.  It's not like I can't trick it to be on with a 5 second play or anything.  

Now to just wait for Amazon to get in stock again...


----------



## garbulky

IBJamon said:


> Ordered.  I will see how much the auto thing bothers me.  It's not like I can't trick it to be on with a 5 second play or anything.
> 
> Now to just wait for Amazon to get in stock again...


Let us know what you think. What headphones do you plan to drive?


----------



## IBJamon

I have Monoprice M1060s, Fostex T50RP Mk3 (which I still need to fix!  blah) and some KZ IEMs and Pioneer SE-A1000s.

They are all modded in some form or other.


----------



## IBJamon

I just realized I do have the Fiio D03k DAC, so if I need to kill some noise I can start there.  It's not fancy or high end, but it should have a lower noise floor until I pony up for a nicer DAC.


----------



## garbulky

IBJamon said:


> I just realized I do have the Fiio D03k DAC, so if I need to kill some noise I can start there.  It's not fancy or high end, but it should have a lower noise floor until I pony up for a nicer DAC.


Oh no, that wont affect the noise floor. 
On very efficient headphones or IEMs you may hear the noise floor of the amp itself (with the jumpers in mode only) - a slight hiss at silence. That won't be affected by your DAC. In regular mode you likely won't hear any noise. You want a dac with volume control so that you can lower the volume with it. In direct drive mode you tend not to be able to control the volume much because it quickly becomes loud with a small turn due to the amps power. So lowering the volume upstream can help you have more realistic control for every day use. Once again that is ONLY for direct drive with the jumpers in mode. In regular mode that's not really a consideration.


----------



## IBJamon

I just meant that I am more or less DAC free at the moment, and will be connecting this fancy amp to my laptop directly.  If it's too noisy or whatever, I could try the D03k which I forgot I had.

I also could use my portable DAC which is no doubt better but I'm tired of connecting and disconnecting it constantly.  My headphone out jack is already starting to wear out, as it disconnects with the slightest touch... (not sure if I will bother contacting the manufacturer but that's probably for another thread.)


----------



## garbulky

IBJamon said:


> I just meant that I am more or less DAC free at the moment, and will be connecting this fancy amp to my laptop directly.  If it's too noisy or whatever, I could try the D03k which I forgot I had.
> 
> I also could use my portable DAC which is no doubt better but I'm tired of connecting and disconnecting it constantly.  My headphone out jack is already starting to wear out, as it disconnects with the slightest touch... (not sure if I will bother contacting the manufacturer but that's probably for another thread.)


Oh I gotcha.


----------



## ra990

Wow, I just put a Chord 2Qute into this amp and it sounds really great. I'm not using any preamp and controlling volume directly on this amp, driving my HE1000 with full power. I've now tried 3 different DACs with this amp and it's very easy to tell them apart, which shows how transparent the amp is. Highly recommended to anyone on the fence.


----------



## torifile

Anyone compare this to the Lyr 2?


----------



## IBJamon (Jan 27, 2018)

Just looking it up, they aren't really the same thing.  The Lyr 2 can be a tube hybrid amp, whereas this is an end-game solid state amp.  The Lyr 2 has about half of the power this does (though that's still quite impressive!) in direct drive mode.

Based on the specs alone, the noise and crosstalk is Much better on this BasX.

I cannot compare the sound quality through listening as my BasX is on order but has not arrived and I have not heard a Lyr 2.

This one is much cheaper, and doubles as a very powerful, real 50Wpc desktop amp.  (Most receivers that claim even 100Wpc rarely hit a proper 50Wpc fully driven like this one does.)

You could probably find a decent tube buffer/preamp if you want to turn this amp quasi-tubey, but whether there is any point to that is certainly up for debate.

I hope that helps.


----------



## sanvara (Jan 28, 2018)

iamjaymo said:


> Don’t have the 600s, I have the 650s. Haven’t tried anything yet other than the AKGs and speakers. I’ll get there...got caught up in listening and enjoying a Police album without analyzing it. If it makes me forget it’s there it’s a good piece of gear!
> 
> _Headphone_ *Apple* MacPro -> *Schiit* Eitr -> *Audio-GD* R2R 11 -> *MrSpeakers *Alpha Dog | *Fostex* TH-X00 Ebony
> _Speaker/Headphone_ *Apple* iMac -> *California Audio Labs* Sigma II -> *Emotiva* A-100 -> *JBL* L-1 | *Sennheiser* HD-6XX



I see you have A-100 and R2R11. Those are the exact two amps I'm looking at buying. The R2R11 is about $150 more. Can you compare your experience with each amp? I know R2R11 has a DAC and A-100 does not. I use HE560, HD650. I have a Modi 2 multibit to use if I decide to buy the A-100.

Also how much of a difference does the Eitr make for you?


----------



## iamjaymo

sanvara said:


> I see you have A-100 and R2R11. Those are the exact two amps I'm looking at buying. The R2R11 is about $150 more. Can you compare your experience with each amp? I know R2R11 has a DAC and A-100 does not. I use HE560, HD650. I have a Modi 2 multibit to use if I decide to buy the A-100.
> 
> Also how much of a difference does the Eitr make for you?



So I use the A-100 primarily as a speaker amp for low-level background music in an office environment.  Occasionally, when the mood strikes, I do listen to the Emotiva as a head amp maybe once or twice a week.  The R2R is my primary headphone amp and I’m on it most of the day.  

I run the A-100 with resistors in play (not in full power mode) as my cans are not all that difficult to drive, save the Alpha Dogs, but even with resistors the Emotiva can get those to ear splitting levels.  I did try the A-100 with the jumpers in but I didn’t hear that much difference (perhaps I didn’t give it enough of a listen to be fair) but I didn’t feel I was missing anything on my particular headphones YMMV.  

Both the A-100 and R2R are great amps.  My opinion of the A-100 may be a bit swayed as I am running it from a tube DAC - a real nice sounding one.  The sound I hear from the A-100 is very open, detailed and smooth.  The A-100 has great dynamics and very nice bass with a smooth top end.

The R2R, in my opinion, is a step ahead...there really is something to the whole “Ladder DAC” thing IMO.  The R2R just offers a bit of a more smoothness and has a more natural sound that is somewhat more analog-ish in it’s delivery.  The bass is a bit softer perhaps through the R2R but it sounds more realistic and not so hard edged as in the A-100 (again, could be the DAC in play here).

I have the fortune of having both amps and they offer something a bit different but both sound fantastic.  The A-100 has more power/drive than the R2R for sure so if you are looking for something to drive power hungry headphones that is something to consider.  I will say, however, the R2R drives everything I have just fine.

In the end, and this is just from my experience, I would say choose the A-100 if you have nice DAC as it’s pretty transparent to the source.  Choose the R2R for an all-in-one solution and a smoother more analog sound.

As for the Eitr… I felt it did make a difference.  A positive one.  If you have the change to spare, get it - that’s about all I can say.  For the price, it’s just worth it.  Simple as that.


----------



## torifile

I’ve got the A-100 and PT-100 en route. How does one control the volume in this setup? I’d like to be able to use the remote that comes with the PT-100. Is that possible?


----------



## garbulky

torifile said:


> I’ve got the A-100 and PT-100 en route. How does one control the volume in this setup? I’d like to be able to use the remote that comes with the PT-100. Is that possible?


Yes you control the volume using the PT-100. 
So you have two ways of running the amp - with and without the jumpers engaged. The default is without the jumpers engaged - this gives lower power. The other is with the jumpers engaged - higher power.
The idea is to use the Mini-x a100 as a power amp - i.e. the volume is controlled by the PT100. 

First set the mini-x a-100 volume knob to the lowest. 
The idea is that you turn the PT100 to say -10.00 or -20 volume. Then slowly bring the mini-x a-100 volume knob UP from mininmum to match till it's the loudest you would want to listen to it at. Then simply control the volume with the pt-100. If you engage the high power version, you will have to get the volume knob on the a-100 high enough that the channel imbalance at the lowest settings go away. It doesn't take much, but if you notice channel imbalance then lower the PT100 some more and turn the volume knob on the a-100 higher..


----------



## torifile

garbulky said:


> Yes you control the volume using the PT-100.
> So you have two ways of running the amp - with and without the jumpers engaged. The default is without the jumpers engaged - this gives lower power. The other is with the jumpers engaged - higher power.
> The idea is to use the Mini-x a100 as a power amp - i.e. the volume is controlled by the PT100.
> 
> ...


Perfect. Thanks!


----------



## sanvara (Jan 30, 2018)

iamjaymo said:


> So I use the A-100 primarily as a speaker amp for low-level background music in an office environment.  Occasionally, when the mood strikes, I do listen to the Emotiva as a head amp maybe once or twice a week.  The R2R is my primary headphone amp and I’m on it most of the day.
> 
> I run the A-100 with resistors in play (not in full power mode) as my cans are not all that difficult to drive, save the Alpha Dogs, but even with resistors the Emotiva can get those to ear splitting levels.  I did try the A-100 with the jumpers in but I didn’t hear that much difference (perhaps I didn’t give it enough of a listen to be fair) but I didn’t feel I was missing anything on my particular headphones YMMV.
> 
> ...



Excellent. Thanks for taking the time to go into such detail. Very helpful. Maybe I will buy both the A100 and the R2R11. I think I'l try the A100 first since that can be returned within 30 days. Did you buy the R2R11 new and did you find it requires a long period of burn in to sound as good as it does?


----------



## garbulky

iamjaymo said:


> So I use the A-100 primarily as a speaker amp for low-level background music in an office environment.  Occasionally, when the mood strikes, I do listen to the Emotiva as a head amp maybe once or twice a week.  The R2R is my primary headphone amp and I’m on it most of the day.
> 
> I run the A-100 with resistors in play (not in full power mode) as my cans are not all that difficult to drive, save the Alpha Dogs, but even with resistors the Emotiva can get those to ear splitting levels.  I did try the A-100 with the jumpers in but I didn’t hear that much difference (perhaps I didn’t give it enough of a listen to be fair) but I didn’t feel I was missing anything on my particular headphones YMMV.
> 
> ...


Glad to hear you gave it a try. I have heard another person say they heard no difference so you're not alone. But at least you know.


----------



## iamjaymo

sanvara said:


> Excellent. Thanks for taking the time to go into such detail. Very helpful. Maybe I will buy both the A100 and the R2R11. I think I'l try the A100 first since that can be returned within 30 days. Did you buy the R2R11 new and did you find it requires a long period of burn in to sound as good as it does?



Yup, my R2R was new and it did require a bit of break-in but not bad. I didn’t really pay much attention as it sounded good from the get go but I think it sounds a bit clearer now (could just be the placebo effect) but I perceive it sounds even better now.

The thing I do notice is that it likes to be warmed up. Generally I feel like a good 20 mins in or so it sounds flush. Just an opinion with no scientific backing whatsoever.


----------



## garbulky

iamjaymo said:


> Yup, my R2R was new and it did require a bit of break-in but not bad. I didn’t really pay much attention as it sounded good from the get go but I think it sounds a bit clearer now (could just be the placebo effect) but I perceive it sounds even better now.
> 
> The thing I do notice is that it likes to be warmed up. Generally I feel like a good 20 mins in or so it sounds flush. Just an opinion with no scientific backing whatsoever.


It's not surprising the warm up. The R2R system is very different from a delta sigma dac. The Schiit Ygdrassil sure needs some "warm up". The Gungnir MB acheived most of its sound after two days but it kept improving slightly for about three weeks.


----------



## m usicguy (Feb 4, 2018)

Well,  I gave my first A-100 to my wife.  With a emotiva xda-2.  She now has one remote control for her headphone set up.  AEon flows for tv!!

I bought another one for my computer audio set up.  Im now running the bypass jumpers.  To power my headphones.   For me the jumpers are the way to go.  Sounds more dynamic, effortless.  I compared this to the cavalli liquid carbon.  I think the emotiva wins.  The liquid carbon when crank up starts to get congested.  Even in balanced set up.  The A-100 just pumps out power.    Now i realize i cant run iem's or low impedance  headphones on the the A-100.  I have found the a-100 to be a great match for planar magnetics. 

The A-100 is the only amp i own that just owns a pair of he-560. 

Maybe emotiva can put more effort into a kick ass headphone amp.  Im looking forward to the balance amp and the new DC-2

m usicguy


----------



## IBJamon

I am considering a jumper switch mod, where you would put an external switch for the jumpers.  It should be as simple as a double pole switch.  I am paranoid about popping my sensitive IEMs, so I hesitate to run it full power all of the time.

Of course I still don't have mine yet because of stupid Amazon... uugh.  I called Emotiva and Amazon and apparently Amazon never ordered more to fill my backorder.  I am more than a little upset with them right now...

They threatened to refund my order if they choose not to get more in the next week or so.  That is a nasty threat since over half of the payment amount was from gift cards.

Well anyway.... lesson?  Buy direct from Emotiva.  Their customer support is excellent - a human picked up the phone after two rings every time I called.


----------



## IBJamon

I drove out to the nearest oldskool electronics store.  It's in the next state over but only 40 minutes away.  Honestly I'm very lucky to live near one at all.

I got a center neutral toggle switch that should allow three different positions; default (middle), higher (with resistors I bought, only 100Ohms) and ludicrous speed (closed).  I haven't wired it together yet, since my amp isn't here yet... but I'm excited about the possibilities.  It's small enough where I can probably just hang the switch out of a vent and use it that way.

Once I get it I'll give it a whirl...


----------



## IBJamon

I saw some reviews complain about hiss with their headphones with this amp.  Is that a common experience?


----------



## ra990

IBJamon said:


> I saw some reviews complain about hiss with their headphones with this amp.  Is that a common experience?


If you put the jumpers in for full power, only then do I hear a hiss past the 3 o'clock position. Silent before that. Without the jumpers, I don't hear any hiss. It's pretty clean.


----------



## iamjaymo

IBJamon said:


> I saw some reviews complain about hiss with their headphones with this amp.  Is that a common experience?



Absolutely dead quiet here...but I don’t have the jumpers in either.


----------



## IBJamon

Thanks for the confirmations.  I'll keep pursuing this thing then.  Hopefully Amazon comes through.... if not hopefully I can convince my wife to let me order this direct...


----------



## garbulky (Feb 4, 2018)

IBJamon said:


> Thanks for the confirmations.  I'll keep pursuing this thing then.  Hopefully Amazon comes through.... if not hopefully I can convince my wife to let me order this direct...


If you have the jumpers in and your headphones are very sensitive then you'll hear the noise floor of the amp. On my HD600, I hear a mild hiss during silence in music passages. It's very mild. The sound is so ridiculously good with the jumpers in that I don't care at all. Without the jumpers in stock configuration there is no hiss that I hear. The headphone amp is also very good in the stock configuration beating out every other amp I've heard. But it's just that with the jumpers in you have some really good quality and power available for you.


----------



## IBJamon

So my order has been updated to ship between feb 22nd and march 6th.  I wonder why so far away... lol

A friend has suggested that the switch could be a recipe for disaster, but to instead add a second jack with the resistors in place (a 3.5mm).  While it's unlikely I'll be drilling holes into the case, it's not a bad idea.  An alternative could be to make an external headphone 6.5mm to 3.5mm adapter that has the resistor(s) in it.  I'll have to look at the wiring when the amp comes in to make a decision.

Fun times!


----------



## torifile

IBJamon said:


> I saw some reviews complain about hiss with their headphones with this amp.  Is that a common experience?


I experienced a hiss at all volumes. Emotiva swapped it out. The new one is also hissing at all volumes.  This occurs with and without the jumpers in both units. I’m thinking of returning mine.


----------



## IBJamon

So I just received it today.  I am relieved to find that I do not hear any hissing!  (Or at least with kids it wasn't noticeable with the background noise.)  I do notice a very faint ground loop/hum, which goes away with the source disconnected and gets louder as the volume goes up, so it's not a problem with the amp.  Ironically, it may be that hum that's keeping the amp from shutting off on auto...

I tested my M1060s and my Fostex T50RP Mk3s.  The Pioneer SE-A1000s also sound very good.  The M1060s do not need more power, but the Fostex need more without the jumper in place.

I will check out the jumper soon, though I don't know if it will be today or not.  We'll see.

I've considered my idea of making a jumper switch, and I may instead make external adapters for other headphones and use them rather than plugging in directly.  More to come.


----------



## IBJamon

Out of the box, these do not have enough power for my T50RP Mk3s.  But unleashed?  Oh wow.  That's all I gotta say.

My other headphones sound incredible in beast mode, but can by used with such a tiny amount of the volume knob it's pointless.  So I gotta try some other stuff.

There is a super tiny amount of hiss with the jumpers in (that the T50s don't even register) but none with the jumpers engaged.  I am fortunate, I suppose.


----------



## garbulky

IBJamon said:


> Out of the box, these do not have enough power for my T50RP Mk3s.  But unleashed?  Oh wow.  That's all I gotta say.
> 
> My other headphones sound incredible in beast mode, but can by used with such a tiny amount of the volume knob it's pointless.  So I gotta try some other stuff.
> 
> There is a super tiny amount of hiss with the jumpers in (that the T50s don't even register) but none with the jumpers engaged.  I am fortunate, I suppose.


Hiss is tiny for me too inaudi ble during music. Reduce volume upstream and move the minix to past volume where there is no channel imbalance and is as loud as you can listen to. For me its  Then control volume upstream of the amp. So in essence minix is a power amp in that mode. This way youll have more control.


----------



## IBJamon

Does anyone know why Emotiva put in a straight resistor rather than a proper voltage divider for the headphone out?  2 extra resistors is not a big cost difference, so that likely isn't it...


----------



## m usicguy

I have two of these amps.  

NO hiss just pure bliss sound.

 I think we all need to remember this is a small speaker amp.  Emotiva is coming out with the new DC-2 and a headphone amp in march maybe april.   Go over to the emo lounge and you will see they are making a dedicated heaphone amp, from what i read unless things have changed.  

The A-100 is a monster for headphones but it is a "hack" for more power.  Tell me of a headphone amp manufacter that makes this much power for 229 dolllars.

m usicguy


----------



## IBJamon

It's a wonderful amp, and I am tickled with it.  I am just trying to make an adapter that I can use with more efficient headphones, while still having 'beast mode' available for my Fostex.  Even my other planars have next to no volume play as things currently are, but I also want to keep the low output impedance, so I am thinking of making a voltage divider rather than a simple resistor as they are currently implemented.


----------



## garbulky

IBJamon said:


> It's a wonderful amp, and I am tickled with it.  I am just trying to make an adapter that I can use with more efficient headphones, while still having 'beast mode' available for my Fostex.  Even my other planars have next to no volume play as things currently are, but I also want to keep the low output impedance, so I am thinking of making a voltage divider rather than a simple resistor as they are currently implemented.


Ask Keith at the Emotiva forums. He'll probably have some advice


----------



## iamjaymo (Feb 20, 2018)

So I gave the jumpers another chance and what I said before about the jumpers not really adding anything wasn't entirely accurate...they do make a difference...quite a difference.  I wasn't using a variable source before so I couldn't get the volume pot past where I needed to in order to avoid channel imbalance, etc.  

I connected using my AGD R2R 11 in variable mode and wow! Magnificent! It's not like the tone changed but it did seem more dynamic and clearer perhaps.  I can liken it to the change the Schiit Eitr had, you can definitely hear it, but it's not like you just saved the world or anything.  It certainly drives my Alpha Dogs better, cleaner, and with more authority.


----------



## iamjaymo

Was looking at the Schiit Jotunheim in order to have more power and drive my Alphas via balanced but I don't think I'm going to need it now.  There is no headphone amp that has more power than this little $229 beast.  Pretty happy with the Emo, it's quite the value proposition.


----------



## garbulky

iamjaymo said:


> So I gave the jumpers another chance and what I said before about the jumpers not really adding anything wasn't entirely accurate...they do make a difference...quite a difference.  I wasn't using a variable source before so I couldn't get the volume pot past where I needed to in order to avoid channel imbalance, etc.
> 
> I connected using my AGD R2R 11 in variable mode and wow! Magnificent! It's not like the tone changed but it did seem more dynamic and clearer perhaps.  I can liken it to the change the Schiit Eitr had, you can definitely hear it, but it's not like you just saved the world or anything.  It certainly drives my Alpha Dogs better, cleaner, and with more authority.


Yay! I knew you'd hear it! I agree about the dynamics. I think this is the mode to run with unless the headphones are way too sensitive for them


----------



## iamjaymo

Interesting tidbit, I have the volume turn up pretty high on the A-100 (about 3:00) and I don’t hear any of the reported “hiss” or any of the amp’s noise floor when no music is flowing. Dead silent.


----------



## IBJamon (Nov 28, 2018)

So I made a few adapters, and learned a few things.  First things first:

If you have inefficient planars like my T50RPs, then by all means use direct mode.  It's awesome!

My more efficient headphones (M1060s, Pio SE-A1000s and of course IEMs) do hear a bit of hiss in direct mode.  It's not bad, but it's there.  As expected they also don't have much play on the volume dial.

So I wanted to have direct mode an easy access, so rather than make a switch like I originally planned, I decided to make some external adapters so I set bridge mode, closed it up, and got to work.

One of my adapters is an exact clone of what's inside; a simple 1/4" to 1/8" adapter with two 220 Ohm resistors soldered right to the jack terminals.  I used ones just like these (except sourced locally, and they are all black):

https://smile.amazon.com/Conwork-6-35mm-Connector-Microphone-Speaker/dp/B072MCDHH4/ref=sr_1_12?ie=UTF8&qid=1519186384&sr=8-12&keywords=1/4+solder+plug

They have enough room to solder a pair of 1 or 2 watt resistors to the terminals inside.

I made another adapter based on this schematic:

https://diyaudioheaven.wordpress.com/headphones/headphone-attenuation-adapter/

For those not familiar, this is also often called an L-pad.

This choice is based on the idea that a low output impedance will sound better.  My first attempt was a DIY fail (parts broke when I was done, etc.) using a box, and I tested with massive 5W resistors using the otherwise same specs as the example (33Ohm/3.3Ohm) and before I broke it (long story) it sounded quite good, though these new ones I made did not exist yet so I couldn't compare them.  So for round two, I made something similar except using 18Ohm/1.8Ohm 2W resistors using the plugs above.  It works, but honestly sounds a bit grainy.  (EDIT: They no longer sound grainy at all.  I normally don't worry about break-in, but they sound fine to me now.)  I also have some 47Ohm/4.7Ohm ones that I believe might sound better.  (The place I bought from didn't have 2W 33/3.3Ohm resistors available.)

You can easily customize the L-pad using the formulas I found on this page:

https://robrobinette.com/HeadphoneResistorNetworkCalculator.htm

I believe the 220Ohm approach may have better crosstalk, while the L pad approach probably works better with some impedance sensitive headphones.  I like having both available, though since my 18Ohm one seems to have a short in it, I may scrap that one for now (and maybe switch it to 47Ohms later since I already have them). 

For the record, the 220Ohm cable attenuates a bit less, but the top half of the dial is worthless because the amp runs out of jiuce (thanks to the crazy high resistance I suspect) whereas the L pad adapter seems to just get louder, despite having more knob room, because it's more useful throughout the power band and the amp has more power to spare since to the amp it thinks the load is much less.

Anyway, I hope that helps and some of you find what I did interesting!


----------



## garbulky

IBJamon said:


> So I made a few adapters, and learned a few things.  First things first:
> 
> If you have inefficient planars like my T50RPs, then by all means use direct mode.  It's awesome!
> 
> ...


Talk to "@KeithEmo" aka keithl on the emo forums. He will very likely give you useful advice. Hes an engineer there. Mention what you tried.


----------



## torifile

I’m jealous of you guys who didn’t have any hiss with the amp. I sent mine back today because the hiss was intolerable.


----------



## LasherV

I just received my A-100 today and man am I pleased  I had one problem though. I missed my Darkvoice 336se Tube sound that I have become addicted to. I decided to try something a little different. I used my Darkvoice as a Pre-Amp to my A-100, it does have pre-outs after all. All I can say is OMG what an amazing upgrade! I have kept all my Tube Warmth, Wide Soundstage, and overall Smoothness that I love soooo much about Tubes, but the Bass has at least tripled on my M1060's. This A-100 has so much dynamic range and punch that the only word that comes to mind is Effortless. If there are any Darkvoice owners out there that are thinking of getting this A-100 as a solid state for your Planars give this a try. I could not be more pleased with what this has done for my listening pleasure. Well guess I'm back to re-rolling all my tubes again to see how they sound with this set up lol.

Lasher


----------



## garbulky

LasherV said:


> I just received my A-100 today and man am I pleased  I had one problem though. I missed my Darkvoice 336se Tube sound that I have become addicted to. I decided to try something a little different. I used my Darkvoice as a Pre-Amp to my A-100, it does have pre-outs after all. All I can say is OMG what an amazing upgrade! I have kept all my Tube Warmth, Wide Soundstage, and overall Smoothness that I love soooo much about Tubes, but the Bass has at least tripled on my M1060's. This A-100 has so much dynamic range and punch that the only word that comes to mind is Effortless. If there are any Darkvoice owners out there that are thinking of getting this A-100 as a solid state for your Planars give this a try. I could not be more pleased with what this has done for my listening pleasure. Well guess I'm back to re-rolling all my tubes again to see how they sound with this set up lol.
> 
> Lasher


Nice!! Have you tried it with the jumpers engaged?


----------



## Namtar

I may have the opportunity to get one of these secondhand from a friend -  Before I make that plunge I am wondering if Emotiva is planning a balanced version of this speaker amp - or a balanced variant dedicated to Headphones.
The Emotiva Forums don't seem to be as active as H-Fi and I'm curious to what the rumor mill is saying since there's obviously a little demand for such a creation.


----------



## IBJamon

I'm pretty sure there are rumors about a dedicated or balanced headphone amp.  For me this one was the way to go because I wanted to upgrade from my crappy lepai desktop amp anyway, so this fit the bill perfectly.


----------



## garbulky (Feb 22, 2018)

IBJamon said:


> I'm pretty sure there are rumors about a dedicated or balanced headphone amp.  For me this one was the way to go because I wanted to upgrade from my crappy lepai desktop amp anyway, so this fit the bill perfectly.


I believe there is a balanced amp coming. BUT...it may not be derived from a mini-x amp with that HUGE amount of power. It may be a more standard headphone amp. That's what I've seen on their old prototypes - which may not be what they are making right now.

I've told them they need to take the A-100, make them in to clsas A monoblock headphone amps at $600 a pop. Also make them dedicated so they are not as noisy in direct drive.   After that, I think it will basically be the king of the desktop headphone market. And honestly I don't think it's going to take a lot of r&d to do that.


----------



## LasherV

garbulky said:


> Nice!! Have you tried it with the jumpers engaged?


Yes the first thing I did was open it up and put in the jumpers. I bought this for the raw power it has and have no problem controlling the volume myself to keep from blowing things up  I also use my Darkvoice as a tube pre-amp so I can limit the power to the front end so I have better range of control at the volume pot. One other cool thing I discovered with this configuration, when I turn on my tube amp the warm up hum from the tubes is enough to trigger the auto-on feature of the A-100 so I can leave it in standby mode full time 

Lasher


----------



## KeithEmo

The reason there is pretty simple.......

We designed the headphone output on the BasX A-100 to act pretty much the way the headphone outputs on most vintage receivers and integrated amplifiers act so we could get a similar sonic signature. A series resistor is the simplest circuit to use, and also the one most commonly seen in vintage equipment. With this circuit topology, the output impedance of the headphone output is equal to the series resistance, which is 220 Ohms. As a result, low impedance headphones, which are often the most sensitive, also see a lower output level - which works out well. But, more importantly, the interaction causes variations in the impedance of your headphones to cause variations in their frequency response. To phrase that differently, it encourages the output of the amplifier to interact with your headphones, rather than the opposite. 

Many modern audiophiles would suggest that this sort of interaction is to be avoided, which is why many modern headphone amplifiers have a very low output impedance. However, even more than with loudspeakers, what a headphone should sound like tends to be a very subjective experience, and a significant number of headphone aficionados feel that the headphone outputs on vintage equipment sound better... and this higher output impedance is the major cause of that difference in sound. Because of that resistor, the output of the BasX A-100 tends to sound different with different headphones, and many headphones will sound different when connected to it than when connected to a headphone amplifier that utilizes a modern design... 

And, because the amplifier circuitry in the A-100 is very quiet, we've eliminated one of the biggest complaints people used to have against the vintage designs.
(Actually, while we've reduced that limitation relative to vintage designs, we couldn't entirely eliminate it.... which is why some people still notice the noise floor on the A-100.)

With the resistors in circuit, the headphone output on the BasX A-100 has an output impedance of 220 Ohms. As a result:
1) the output level (gain) works reasonably well with a wide variety of different headphones
2) the frequency response of the output tends to interact with the individual headphones you connect to it (giving each a bit of its own "personality")
3) the damping factor applied to the headphones is relatively low (which also affects the way they sound)
4) because of 2) and 3), the headphone output of the A-100 tends to mimic the sound of the headphone outputs on vintage equipment

With the resistors bypassed, the output impedance is very low ( a tiny fraction of an Ohm). As a result:
1) the output level (_VOLTAGE_) is essentially load independent
2) the damping factor applied to the headphones is very high
3) the frequency response of the output does NOT interact with the individual headphones you connect to it (this is the way most modern headphone amplifiers act)
4) the noise floor is slightly higher (this is a slight drawback due to some of the other optimizations)
5) the A-100 is capable of delivering dangerously high output levels to low-impedance headphones (which is why all the warnings)
6) the A-100 is capable of delivering the very high output levels some early low-efficiency planar headphones required

In comparison to the approach we chose, using an L-pad will yield a significantly lower output impedance.

With a simple series resistor, and an amplfier with a near-zero internal impedance, the output impedance simply equals the series resistance = 220 Ohms.
With a simple L-pad, and the same amplifier, the output impedance is equal to the PARALLEL COMBINATION of the two resistors in the L-pad.
So, for example, if you use an L-pad with a 33 Ohm resistor and a 3.3 Ohm resistor, the output impedance works out to slightly below 3 Ohms. 
This is very similar to the output impedance of many modern headphone amps.
And, with the resistors bypassed, and no L-pad or other attenuator, the output impedance will be super low (and the damping super high).

Also note, when designing attenuators and L-pads, that the maximum output on the BasX A-100 is 25 volts RMS... which is significant.
Therefore, with certain resistor values, and depending on the levels you typically listen at, your resistors may need to handle a LOT of power.

For example, the BasX A-100 is rated to deliver about 80 watts into 8 Ohms.
This means that, when playing a continuous tone, it CAN deliver as much as 18 watts into a 33 Ohm L-pad.....
And as much as about 35 watts into an 18 Ohm L-pad.....
And most of that power is going to heat the "top" resistor in that L-pad.....
Obviously this isn't going to be an issue at lower power levels, and, since music is dynamic, sustained very high levels are quite rare...but you should be aware of the possibility.
(If you make an 18 Ohm L-pad, and inadvertently turn the amp all the way up one day, your L-pad may actually catch fire.
More importantly, power resistors can get very hot - hot enough to melt plastic and burn your hands - even when operating within safe ratings.)



IBJamon said:


> Does anyone know why Emotiva put in a straight resistor rather than a proper voltage divider for the headphone out?  2 extra resistors is not a big cost difference, so that likely isn't it...


----------



## garbulky

KeithEmo said:


> The reason there is pretty simple.......
> 
> We designed the headphone output on the BasX A-100 to act pretty much the way the headphone outputs on most vintage receivers and integrated amplifiers act so we could get a similar sonic signature. A series resistor is the simplest circuit to use, and also the one most commonly seen in vintage equipment. With this circuit topology, the output impedance of the headphone output is equal to the series resistance, which is 220 Ohms. As a result, low impedance headphones, which are often the most sensitive, also see a lower output level - which works out well. But, more importantly, the interaction causes variations in the impedance of your headphones to cause variations in their frequency response. To phrase that differently, it encourages the output of the amplifier to interact with your headphones, rather than the opposite.
> 
> ...


Keith you really impressed me with this response. Thank you for taking the time here to post these technical details. If you've read the rest of this thread you'll see a lot of people are very impressed at this insanely good headphone amp Emo has produced. I know I'm having a fantastic time with it. Thanks.


----------



## IBJamon

KeithEmo said:


> The reason there is pretty simple.......
> 
> We designed the headphone output on the BasX A-100 to act pretty much the way the headphone outputs on most vintage receivers and integrated amplifiers act so we could get a similar sonic signature. A series resistor is the simplest circuit to use, and also the one most commonly seen in vintage equipment. With this circuit topology, the output impedance of the headphone output is equal to the series resistance, which is 220 Ohms. As a result, low impedance headphones, which are often the most sensitive, also see a lower output level - which works out well. But, more importantly, the interaction causes variations in the impedance of your headphones to cause variations in their frequency response. To phrase that differently, it encourages the output of the amplifier to interact with your headphones, rather than the opposite.
> 
> ...




Thank you so much for replying to me!  That was a very insightful answer - and makes a lot of sense.  I made a few different adapters to test with, and indeed the sound is different with each one.  As you said, it could get hot - which is why I chose 2-5W resistors rather than smaller ones - but the chances of them getting that hot in real use are slim.

Thank you again for replying here, and for making such an excellent amplifier!  (I own other emo products also - great stuff!)


----------



## urez

Hello!
May be someone used BasX A-100(bypass the resistors of course) with Abyss 1266 ?
Have some thoughts to buy one before i'll get money for Headtrip/Sim 600i...


----------



## talmadge

LasherV said:


> I just received my A-100 today and man am I pleased  I had one problem though. I missed my Darkvoice 336se Tube sound that I have become addicted to. I decided to try something a little different. I used my Darkvoice as a Pre-Amp to my A-100, it does have pre-outs after all. All I can say is OMG what an amazing upgrade! I have kept all my Tube Warmth, Wide Soundstage, and overall Smoothness that I love soooo much about Tubes, but the Bass has at least tripled on my M1060's. This A-100 has so much dynamic range and punch that the only word that comes to mind is Effortless. If there are any Darkvoice owners out there that are thinking of getting this A-100 as a solid state for your Planars give this a try. I could not be more pleased with what this has done for my listening pleasure. Well guess I'm back to re-rolling all my tubes again to see how they sound with this set up lol.
> 
> Lasher



Lasher how do you use the volume controls on this setup? Do you set the emotiva at a certain point then use the darkvoice to control the volume or the opposite? I have a darkvoice 336 and an OPPO HA 1 and would like to try this combo.


----------



## LasherV

talmadge said:


> Lasher how do you use the volume controls on this setup? Do you set the emotiva at a certain point then use the darkvoice to control the volume or the opposite? I have a darkvoice 336 and an OPPO HA 1 and would like to try this combo.


I set the Darkvoice to around 11 o’clock and use the Emotiva volume. It’s a better volume pot IMHO. It’s pretty easy to find a happy medium adjusting between 10-11 o’clock on the Darkvoice depending on what Tubes/Source you are using. Let me know how it works out with the HA-1. I love the setup with my Emotiva and my new M1060C’s. Hope this helps 

Lasher


----------



## Bitman

I bought the A-100, liked it, but returned it due to the oddball size: 8.5” wide x 3.125” high x 15” deep (includes feet, binding posts, and Volume knob).
Additi0nally, the volume knob has no indicator (neither digital read-out nor 'light dot') to determine when it gets to "11''.
All the best Bitmann


----------



## peepr

I've recently added this to the chain, mostly to get better volume control and leeway from the A-100. Don't know if it's improved the sound or not but it does sound amazing. Very pleased. Was about $30 from amazon. https://www.amazon.com/gp/product/B07545WKJR/ref=oh_aui_detailpage_o08_s00?ie=UTF8&psc=1


----------



## Pedro Janeiro

jwedwards75 said:


> I recently purchased the Emotiva A-100 amp and I am really impressed. It is easily better than my Schiit Magni 2 Uber or my JDS O2. Not. Even. Close. I use this amp with my HD 600s and 400is. However, I did try the Pangea AC-14 C-7 power cable. It sounded awful with this amp on first listen; I let it "burn in" for 30-35 hours, and the sound did not improve. With the Pangea, the Emotiva sounded like a veil had been placed over the sound on each of my 'phones. I was actually skeptical about whether a cable could make any difference whatsoever, and to my amazement I could not only hear a difference, but it was appreciably worse. What did improve the amp's sound was switching from Monoprice (and other generic) RCAs to Audioquest Evergreen cables These cables to my various dacs transformed a very good amp into an amazing one. I've heard details in my music that I didn't know where there before. Who knew that a cable could impact the sound so much?


 
Hi there, 

im looking for a headphone amp for my grado gh2, do you think the emotiva A-100 sounds better than audeze deckard or even Schiit Jotunheim?
thanks


----------



## iamjaymo (Mar 18, 2018)

Pedro Janeiro said:


> Hi there,
> 
> im looking for a headphone amp for my grado gh2, do you think the emotiva A-100 sounds better than audeze deckard or even Schiit Jotunheim?
> thanks



I had both (A-100 BasX and Jot) in my rig at the same time for a short while...I liked the Emo better overall.  Initially I liked the Jot as it was exciting and VERY detailed, kinda sounded "hot", if you will, but in the end I preferred the Emo as I found it a bit smoother in the treble.  YMMV.

During the comparison, I ran the Emo with the jumpers in place and I used the Jot both balanced and single-ended.  Over the long haul, the Emo had the combination of power (with jumpers), price ($229...really!?!) and the ability to drive passive speakers which helped it win out for me. The Jotunheim is also a fantastic amp and I wouldn’t hesitate to recommend it, esp if you are running balanced.


----------



## Pedro Janeiro

iamjaymo said:


> I had both (A-100 BasX and Jot) in my rig at the same time for a short while...I liked the Emo better overall.  Initially I liked the Jot as it was exciting and VERY detailed, kinda sounded "hot", but in the end I preferred the Emo as I found it a bit smoother over the long haul.  YMMV.





iamjaymo said:


> I had both (A-100 BasX and Jot) in my rig at the same time for a short while...I liked the Emo better overall.  Initially I liked the Jot as it was exciting and VERY detailed, kinda sounded "hot", if you will, but in the end I preferred the Emo as I found it a bit smoother in the treble.  YMMV.
> 
> During the comparison, I ran the Emo with the jumpers in place and I used the Jot both balanced and single-ended.  Over the long haul, the Emo had the combination of power (with jumpers), price ($229...really!?!) and the ability to drive passive speakers which helped it win out for me. The Jotunheim is also a fantastic amp and I wouldn’t hesitate to recommend it, esp if you are running balanced.




Thanks for your fast message.

I think both the Emotiva A100 basX and Jotunheim are Class A/B, and the Audeze Deckard class A, do you think i can notice any diference between that? you already tryed that amp from Audeze?

thanks


----------



## MyPants

Howdy all. I have a set of Audeze LCD-2Cs on the way, and I'm trying to make sense of a power conversion using this site https://www.the12volt.com/ohm/ohmslawcalculators.asp. It looks like the A100's 50w into 8ohms is 20v. 20v at 70ohms is 5.7w or juuuuust above the maximum power handling of the LCD-2C. Does this mean that a good amount of the volume knob on an A100 with the jumpers installed would actually be safe for the LCD-2C, or am I missing something in the math?


----------



## KeithEmo

Your math looks about right... but you are missing a few important concepts.

The Volume control determines how much GAIN the amplifier applies to the signal.... how much the amp boosts the incoming signal. Therefore, how much power you get out at a given setting of the knob depends on the level of the INPUT signal. With a very quiet source, you might be delivering full power with the Volume knob 3/4 of the way up, while, with a very loud source, you might be at full power with the knob 1/4 of the way up. Unless you're actually using a meter, you should ALWAYS pay attention to how loud your equipment is actually PLAYING, rather than where the knob is set.

However, as a general statement, because those headphones are rated to handle a lot of power, it means that you will be SAFE to play them very loudly, and you won't have to worry about being super-careful with that Volume control. If you have them on, you should worry more about blowing out your eardrums than the headphones. Also note that music is quite dynamic; so the loudest peaks are usually somewhere between 10x and 20x the average level. That means that, if you play music so loudly that the loudest peaks are clipping at 5 watts, the average level is probably closer to 0.25 watts or 0.5 watts... which shouldn't be dangerous for the phones at all.

But, yes, headphones rated for that much power will be VERY happy with an amp that can supply it like the A-100... and you won't have to be unduly careful about damaging them.



MyPants said:


> Howdy all. I have a set of Audeze LCD-2Cs on the way, and I'm trying to make sense of a power conversion using this site https://www.the12volt.com/ohm/ohmslawcalculators.asp. It looks like the A100's 50w into 8ohms is 20v. 20v at 70ohms is 5.7w or juuuuust above the maximum power handling of the LCD-2C. Does this mean that a good amount of the volume knob on an A100 with the jumpers installed would actually be safe for the LCD-2C, or am I missing something in the math?


----------



## MyPants

Thank you, that was extremely helpful. I'll most likely be running it downstream of my Asgard 2's pre-outs so I'll be able to adjust the input signal level manually and precisely. As a side question, does the rca passthrough function while the unit is off, or does the muting relay cut everything off as in the Asgard? (I ask because the next step in the chain is powered monitors.)



KeithEmo said:


> Your math looks about right... but you are missing a few important concepts.
> 
> The Volume control determines how much GAIN the amplifier applies to the signal.... how much the amp boosts the incoming signal. Therefore, how much power you get out at a given setting of the knob depends on the level of the INPUT signal. With a very quiet source, you might be delivering full power with the Volume knob 3/4 of the way up, while, with a very loud source, you might be at full power with the knob 1/4 of the way up. Unless you're actually using a meter, you should ALWAYS pay attention to how loud your equipment is actually PLAYING, rather than where the knob is set.
> 
> ...


----------



## garbulky

MyPants said:


> Thank you, that was extremely helpful. I'll most likely be running it downstream of my Asgard 2's pre-outs so I'll be able to adjust the input signal level manually and precisely. As a side question, does the rca passthrough function while the unit is off, or does the muting relay cut everything off as in the Asgard? (I ask because the next step in the chain is powered monitors.)


Yes use the pre to adjust the volume. What I do is I use the mini-x as a power amp. First I reduce my pre a little from max volume. Then I increase the volume on the mini-x from zero to the loudest I will normally use it. Then after that I just use my preamp upstream to adjust the volume from there. This prevents any wonkiness with using the volume control in direct drive mode.


----------



## sonic2911

Is it safe to drive HD650 directly?


----------



## KeithEmo

Absolutely...

The HD650 is 300 Ohms, so it's perfectly safe to run them on the A-100 with or without the jumpers.



sonic2911 said:


> Is it safe to drive HD650 directly?


----------



## sonic2911

Driving my HE400 with jumpers, I can hear noise even volume 0 or turn off my DAC while not without jumpers


----------



## iamjaymo

sonic2911 said:


> Is it safe to drive HD650 directly?



When I had them, I drove the HD-6XX right from the jumpered A-100 with no issue at all.  Didn't use a variable source volume control either, had enough volume play and could go up to about 10:00 on the volume dial.  Good to go.


----------



## quimbo

Will this drive 600ohm headphones such as the AKG K240 MP Sextett


----------



## iamjaymo (Mar 21, 2018)

quimbo said:


> Will this drive 600ohm headphones such as the AKG K240 MP Sextett



Well with the jumpers in place the A-100 pumps out 600mW at 600 Ohms...I’m guessing it will drive them just fine. I haven’t seen too many headamps put out that kind of juice.


----------



## KeithEmo

Sure..... it will easily drive _ANY_ 300 Ohm or 600 Ohm cans.



quimbo said:


> Will this drive 600ohm headphones such as the AKG K240 MP Sextett


----------



## iamjaymo

sonic2911 said:


> Driving my HE400 with jumpers, I can hear noise even volume 0 or turn off my DAC while not without jumpers



My hearing must suck cuz I don’t hear any noise with the jumpers in play.


----------



## quimbo

KeithEmo said:


> Sure..... it will easily drive _ANY_ 300 Ohm or 600 Ohm cans.



Great.  I will be picking one up so, thank you for the quick response.  I don;t think my current amp is properly driving them


----------



## MyPants

My BasX A100 showed up today and I immediately installed the jumpers. With HD280 Pros there is somewhat significant idle hiss but it seems to go away or be otherwise imperceptible when music is playing. With my HE400i however, there is no noise floor whatsoever. With the TH-X00 there is SOME noise floor not not much, so it appears to vary pretty widely. Overall it sounds GREAT. I'm extremely pleased and can't wait to hear the LCD-2C on it tomorrow.


----------



## garbulky

MyPants said:


> My BasX A100 showed up today and I immediately installed the jumpers. With HD280 Pros there is somewhat significant idle hiss but it seems to go away or be otherwise imperceptible when music is playing. With my HE400i however, there is no noise floor whatsoever. With the TH-X00 there is SOME noise floor not not much, so it appears to vary pretty widely. Overall it sounds GREAT. I'm extremely pleased and can't wait to hear the LCD-2C on it tomorrow.


Glad you like it Schiitmypants. I have a feeling that LCD-2C is going to sound all kinds of fantastic!


----------



## garbulky

So after some searching I found an integrated unit that was almost comparable to the mighty Basx A-100 (for the HD600). It was the Mytek Liberty DAC with my HD600. The sound really is quite similar with lots of control. The A-100 has more volume at the extremes but the extremes are really loud - so loud the HD 600 can't really handle it. A headphone that;s meant to soak up more power will probably still beenfit quite a lot from the A-100. 

You still have to go through the Mytek DAC so I couldn't just feed it my DC-1. The Mytek DAC is also quite good so there is a slight tonal difference. The Liberty is almost $1000. It's realyl nice and the size is smaller. So if anybody is looking for a more portable use  but a really stunning headphone amp, but doesn't mind the price, the liberty is pretty great - for my Sennheisser HD600.


----------



## iamjaymo (Mar 21, 2018)

I just pickup the LCD2C’s as well...just got ‘em today, can’t wait to hook them up to the Emo tomorrow.


----------



## MyPants

iamjaymo said:


> I just pickup some LCD2C’s as well...just got ‘em today, can’t wait to hook them up to the Emo tomorrow.



I'm excited to compare impressions of the pairing.


----------



## iamjaymo

MyPants said:


> I'm excited to compare impressions of the pairing.



Yes, for sure


----------



## matttheazn (Mar 21, 2018)

hey everyone, i just got my a100 to use with my new hd600s that are on the way.  testing with my low impedance v moda crossfades i can hear some slight noise coming from the amp, is this normal?  Also i am hearing bleed when the volume is all the way down?  is this normal for low impedance headphone on an amp when none is needed to drive the cans?  thanks for any help.  seems like the consensus is to put the jumpers in with the 600s, am I correct?  they are currently out right now.


----------



## YourMomsBoyFriend

Does anyone have the Monolith M1060 headphones? How's the noise with the jumpers installed? If it has noise, how much is it compared to headphones around 32 ohm and 100 db/mw sensitivity if you have some to compare? This information is greatly appreciated.


----------



## MyPants (Apr 2, 2018)

YourMomsBoyFriend said:


> Does anyone have the Monolith M1060 headphones? How's the noise with the jumpers installed? If it has noise, how much is it compared to headphones around 32 ohm and 100 db/mw sensitivity if you have some to compare? This information is greatly appreciated.



I can't speak to the M1060 directly, but I suspect you'll have some noise floor with the jumpers installed. The TH-X00 Purpleheart is 25ohm 94db/mw and I have some noise floor there. If I'm listening to hip-hop or electronic it's not really an issue, but if I'm gonna listen to some jazz, blues, vocal, classical, etc. anything that relies on a black background, I switch over to my Asgard. There's a little bit of noise floor even with the LCD-2C, so I don't think I'd use the Emotiva as my only amp BUT it's a great supplement to an existing system if you want the option of massive power at the expense of some mild noise floor..


----------



## YourMomsBoyFriend

MyPants said:


> I can't speak to the M1060 directly, but I suspect you'll have some noise floor with the jumpers installed. The TH-X00 Purpleheart is 25ohm 94db/mw and I have some noise floor there. If I'm listening to hip-hop or electronic it's not really an issue, but if I'm gonna listen to some jazz, blues, vocal, classical, etc. anything that relies on a black background, I switch over to my Asgard. There's a little bit of noise floor even with the LCD-2C, so I don't think I'd use the Emotiva as my only amp BUT it's a great supplement to an existing system if you want the option of massive power at the expense of some mild noise floor..


Thanks for the examples, this is very helpful.


----------



## Namtar

I'm wondering if anyone here has used this amp with the massdrop he-4xx with the jumpers and what their impressions were.  Same for the massdrop 6xx cans as I'm considering getting those as well later on.  I enjoyed my senn 598 cans a long time ago and I'm considering giving dynamic drivers another go.
Currently I have a marantz receiver which I'm using to power my cans from the headphone jack (also used to power my speakers) but I'm wondering if the 50w would be of benefit to me.  My source sorta sucks as it's just my onboard sound from my motherboard but that's a later upgrade.


----------



## peepr

Namtar said:


> I'm wondering if anyone here has used this amp with the massdrop he-4xx with the jumpers and what their impressions were.  Same for the massdrop 6xx cans as I'm considering getting those as well later on.  I enjoyed my senn 598 cans a long time ago and I'm considering giving dynamic drivers another go.
> Currently I have a marantz receiver which I'm using to power my cans from the headphone jack (also used to power my speakers) but I'm wondering if the 50w would be of benefit to me.  My source sorta sucks as it's just my onboard sound from my motherboard but that's a later upgrade.


I use the a-100 with my HD650 and its awesome. Highly recommended. I also use a vintage pioneer receiver with them which sounds just as good, so if your Marantz is vintage it should be fine. Is it?


----------



## Namtar

I would say it's older but not consider it "vintage".  SR7000 is the model number.  I think it's from 1999 or 2000.  
I just know I'm wanting a small upgrade when I get my tax return - so I'm going to redo the audio setup.  I'd love to use the Marantz as a DAC but it won't allow Optical In to Analog Out.   
Amp is next, then probably a 2nd set of headphones, then a DAC.   So long as I like the A100 I'll likely just use it for both my speakers and headphones (and move the Marantz - possibly to my wifes computer if she wants it) since I believe I read somewhere it mutes the Speaker Out when headphones are plugged in.  I just have to be careful at that point with volume control so I don't blow up a set of headphones.  I don't have a proper preamp since my Schiit Sys went out on me for some reason.


----------



## garbulky

Exciting news Emotiva is coming out with a new headphone amp! It's balanced and in full class A. 
Big Dan announced it
"HP-1 Class A balanced headphone amplifier! 

4 watts per channel, discrete Class A design. +/- 27 VDC rails!!!!

Talk about headroom. Great for both low and high impedance headphones. Selectable gain, etc."


----------



## garbulky

garbulky said:


> Exciting news Emotiva is coming out with a new headphone amp! It's balanced and in full class A.
> Big Dan announced it
> "HP-1 Class A balanced headphone amplifier!
> 
> ...


I'm not sure what +/-27vdc rails translates to in watts @ 300 ohms and I sure would like to know!


----------



## kukkurovaca

garbulky said:


> I'm not sure what +/-27vdc rails translates to in watts @ 300 ohms and I sure would like to know!



I think voltage swing ≠ power output. I would actually love to have a breakdown of how to interpret voltage swing specs for non-technical folks like me...


----------



## Namtar

I'm wondering the price point compared to the A100 (and the other similarly priced amps - say from Schiit) .  That's going to be the interesting part.


----------



## targetrein

A little background:  I'm coming from an O2 amp + Mad Dog, a combination I've used for several years.  I sent the Dog's in for Dan's 'Prime' upgrade back in February.  They're scheduled to arrive on Thursday, finally.  

I have my new Emotiva A-100 sitting at the office waiting for the Alpha Primes and couldn't help myself.  Today, I plugged in my buddy's M50x's in and geezus....  I know it's complete overkill (I'm using full power - resistor bypass) - crazy how much a little power can open up a set of cans.  

That being said, there is constant hiss, even at low / no volume.  At moderate music volume, hiss is fairly negligible.  I'm guessing it's due to the M50's efficiency and the Primes will be better suited for the amp - the hiss won't be as noticeable.  Right?  

Anyway, power.  Lots of power.  Hot damn.


----------



## lambdastorm

targetrein said:


> A little background:  I'm coming from an O2 amp + Mad Dog, a combination I've used for several years.  I sent the Dog's in for Dan's 'Prime' upgrade back in February.  They're scheduled to arrive on Thursday, finally.
> 
> I have my new Emotiva A-100 sitting at the office waiting for the Alpha Primes and couldn't help myself.  Today, I plugged in my buddy's M50x's in and geezus....  I know it's complete overkill (I'm using full power - resistor bypass) - crazy how much a little power can open up a set of cans.
> 
> ...


These are pretty much unusable with any headphones cept planars and high impedance cans. You can't twist the volume knob too much without blowing the drivers.


----------



## targetrein

Yeah, volume is set at a quarter.  Any more and these M50s will explode.  Can't wait for the Primes - they're gonna sing


----------



## m usicguy

Try turning down your source output some and then add in some volume with the a-100

Your going to love the a-100 with mr speakers prime.  Im running my alpha primes and this amps makes them sing.   I normally have my dac at -15 db and jumpers installed on the a-100.   volume is also at 1 o clock no hiss.

this amp really shines when you need good sound with low compressed digital files.  Like prince and early 80's cd's.  This is my fav amp to listen to Onigo Boingo Alive double cd!!!



m usicguy


----------



## targetrein

m usicguy said:


> Your going to love the a-100 with mr speakers prime.  Im running my alpha primes and this amps makes them sing.   I normally have my dac at -15 db and jumpers installed on the a-100.   volume is also at 1 o clock no hiss.




That's reassuring - you're pretty much using the same setup as I will be and you've got no hiss.  Excellent.

I'll be running FLAC from an iBasso DX90.  

For once, I'm going to be excited to go to work on a Friday morning


----------



## KeithEmo

THERE IS A SIMPLE SOLUTION.....

If you find that your headphones are so sensitive that you can barely move the Volume control on the A-100 off the bottom stop....
Or, if you find that, because you end up with the Volume knob so near the bottom stop, there is a slight but annoying channel imbalance....
Or, if you find that there is too much background hiss, AND THE HISS IS COMING FROM THE SOURCE (you'll know because the hiss will drop when you turn off or disconnect the source).

The solution is to "lower the gain structure of the A-100" by putting a pair of passive attenuators between your source and the inputs on the A-100.
For example, if you put a pair of 12 dB passive attenuators on the input, then you will end up turning the Volume knob on the A-100 12 dB higher to achieve the same output level as before.
This will "put the knob on the A-100 in a higher and more linear portion of its control range".

Note that, while this will not lower the noise floor of the A-100 itself, if the output of your source component has a noise floor, and that's what you're hearing, this may reduce it significantly.
(The result will depend on exactly where in the circuitry of your source component the noise is coming from.)

If you want to try this, I would recommend these (and they are quite economical).....
https://www.parts-express.com/harrison-labs-12-db-rca-line-level-audio-attenuator-pair--266-244



lambdastorm said:


> These are pretty much unusable with any headphones cept planars and high impedance cans. You can't twist the volume knob too much without blowing the drivers.


----------



## iamjaymo (Apr 9, 2018)

lambdastorm said:


> These are pretty much unusable with any headphones cept planars and high impedance cans. You can't twist the volume knob too much without blowing the drivers.



You’re right! If I plug my 25 ohm Fostex dynamics, I hear a slight buzz/hiss. When I connect my harder to drive planars, I hear the music and that’s all. Variable source eliminates all this as the previous poster indicated. All good.


----------



## lambdastorm (Apr 9, 2018)

KeithEmo said:


> THERE IS A SIMPLE SOLUTION.....
> 
> If you find that your headphones are so sensitive that you can barely move the Volume control on the A-100 off the bottom stop....
> Or, if you find that, because you end up with the Volume knob so near the bottom stop, there is a slight but annoying channel imbalance....
> ...


Thanks a lot for the reply Keith, your awesome.

From what I know most of the time the amp itself is the issue, not the dac. These are designed to mate with planars and high-impedance cans, so its only reasonable that they have too much gain/volume for high-sens/low-impedance cans.
Right now I'm driving my Abyss with these and I have to say that, even for headphones as inefficient as Abyss (on par with HE6) there's still too little usable volume. I'm able to turn the volume knob past channel imbalance point but that's pretty much where it starts to get too loud. Here's what I did:

I made a pair of speaker taps to XLR adapter with cheap Belden speaker cables, one end terminated with banana plugs (+/-) and the other 3-pin female XLR (GND/+/-) . This combination works very well and so far there's no channel imbalance, not even at the lowest volume. BUT I do think my Abyss sounds better single-ended. I don't exactly know why as balanced is supposed to be more resolving and airy, but to my ears single-ended is just more euphonic and easy on the ears. I do know tho that some users prefer single-ended to balanced so I guess I'm not the only one........

I want to buy the attenuator you recommended, it really seems like I can get more usable volume out of these. Few questions tho:

1. Does it muddy the sound in any way? Would I hear less details or get less dynamic range?

2. Does it work by dropping the voltage from the source?

Thanks.


----------



## lambdastorm

iamjaymo said:


> You’re right! If I plug my 25 ohm Fostex dynamics, I hear a slight buzz/hiss. When I connect my harder to drive planars, I hear the music and that’s all. Variable source eliminates all this as the previous poster indicated. All good.


Or there's a better solution: 

make yourself a speaker tap to 2*3-pin XLR connectors and free up the front 1/4 port. That way you can leave the jumpers unengaged for hiss-sensitive headphones and drive your planar to another level . Win-win.


----------



## IBJamon

My solution was to put an adapter in-line with my headphones that need the attentuation.  I detailed it in a post on page 15:

https://www.head-fi.org/threads/emotiva-a-100.825970/page-15#post-14057326

The 'grainyness' from the adapters I made went away, and I use them almost all of the time with my Monoprice M1060s, and I bypass the adapter for my Fostex's.


----------



## KeithEmo

Yes, attenuators work by directly dropping the signal voltage (and dropping the noise by an equal amount).

In engineering terms, an attenuator should have no effect whatsoever on dynamic range, detail, or anything else.
What they're doing is lowering the overall gain structure (so, since everything is lowered by the same amount, dynamic range and detail are not affected).
It is possible, however, that a certain piece of equipment itself might sound different when operated in a different portion of its gain range.
It's pretty easy to make an attenuator that produces no "side effects" and I've never heard any difference (other than the intended level shift) when using these particular ones.




lambdastorm said:


> Thanks a lot for the reply Keith, your awesome.
> 
> From what I know most of the time the amp itself is the issue, not the dac. These are designed to mate with planars and high-impedance cans, so its only reasonable that they have too much gain/volume for high-sens/low-impedance cans.
> Right now I'm driving my Abyss with these and I have to say that, even for headphones as inefficient as Abyss (on par with HE6) there's still too little usable volume. I'm able to turn the volume knob past channel imbalance point but that's pretty much where it starts to get too loud. Here's what I did:
> ...


----------



## MyPants

Is there any reason other than price that fixed attenuators would be preferable to a passive pre-amp (ex. JDS Labs OL Switcher @ $45)? Assuming that your pre has a quality volume pot, you shouldn't be introducing channel imbalance. In my system I put the A100 downstream from my Asgard's pre-out, so I can infinitely vary the input signal to match whatever headphones I plug into the A100. This way you don't have to settle for a particular level of attenuation.


----------



## KeithEmo

MyPants said:


> Is there any reason other than price that fixed attenuators would be preferable to a passive pre-amp (ex. JDS Labs OL Switcher @ $45)? Assuming that your pre has a quality volume pot, you shouldn't be introducing channel imbalance. In my system I put the A100 downstream from my Asgard's pre-out, so I can infinitely vary the input signal to match whatever headphones I plug into the A100. This way you don't have to settle for a particular level of attenuation.


----------



## KeithEmo

Not at all......

However, even high quality Volume pots tend to have some channel imbalance down near the bottom of their range, while even low cost attenuators tend to be very precise.



MyPants said:


> Is there any reason other than price that fixed attenuators would be preferable to a passive pre-amp (ex. JDS Labs OL Switcher @ $45)? Assuming that your pre has a quality volume pot, you shouldn't be introducing channel imbalance. In my system I put the A100 downstream from my Asgard's pre-out, so I can infinitely vary the input signal to match whatever headphones I plug into the A100. This way you don't have to settle for a particular level of attenuation.


----------



## maheeinfy

Other than headphone jack, what else is improved in Basx a-100 from old model


----------



## Shazb0t

maheeinfy said:


> Other than headphone jack, what else is improved in Basx a-100 from old model


I'm curious about this as well.  I have had a mini-x for a few years, before the basX was offered.


----------



## iamjaymo (Apr 14, 2018)

maheeinfy said:


> Other than headphone jack, what else is improved in Basx a-100 from old model





Shazb0t said:


> I'm curious about this as well.  I have had a mini-x for a few years, before the basX was offered.



As mentioned, the single-ended headphone jack.  The "special" headphone feature allowing the headphones to be run at full amplifier power with the following specs:

8 Ohms:  50 watts / channel
33 Ohms:  12 watts / channel
47 Ohms:  8.5 watts / channel
150 Ohms:  2.6 watts / channel
300 Ohms:  1.3 watts / channel
600 Ohms:  0.6 watts / channel

Also, the on/off/auto power trigger I believe.  I'm sure some upgrades to the internals which others are more qualified to answer.  There is even one for sale on this forum! (wink...wink...)


----------



## Yevgen Chupak

Hey guys. I need your help.
I have a combo of Fostex A4BL + Emotiva A100 Bas X as my external amplifier for some hard cans.
And whenever I'm using my Shure 1540 I can hear EMI hiss A LOT (can hear much less with Senh hd600 and Shure 846). Those cans are pretty sensitive unlike my many others (Fostex, Senh, Sony, M1060 etc)

If I USB cable is unplugged from A4 hiss is almost gone (stock silver cable). I thought that if I will get myself AQ Jitterbug it will fix my problem but nope... no difference.

So my question is anyone of you have the same problem with A4 as or any other DAC and what is the way to fix that? So should I go and buy some fancy USB A-B cable? Or I should get Linear Power Supply for A4? Anything?


----------



## lambdastorm

Yevgen Chupak said:


> Hey guys. I need your help.
> I have a combo of Fostex A4BL + Emotiva A100 Bas X as my external amplifier for some hard cans.
> And whenever I'm using my Shure 1540 I can hear EMI hiss A LOT (can hear much less with Senh hd600 and Shure 846). Those cans are pretty sensitive unlike my many others (Fostex, Senh, Sony, M1060 etc)
> 
> ...


You're pair 846 with these??


----------



## Yevgen Chupak

lambdastorm said:


> You're pair 846 with these??



just to try will i hear that hiss or not. My mac (source) was muted.


----------



## lambdastorm

Yevgen Chupak said:


> just to try will i hear that hiss or not. My mac (source) was muted.


Did you hear any?


----------



## KeithEmo

If you're hearing that sort of chortling noise that's typical of EMI, and it goes away when you disconnect the computer, or when the computer is powered down, then it's probably noise on the USB ground of the computer. The solution is to use a USB isolator. (A REAL galvanic isolator... not a noise filter type thingy like the Jitterbug. A fancy cable isn't going to help either, unless it includes a galvanic isolator. A different power supply MIGHT help - not because it's "better power", but because it's grounded slightly differently... but that's less likely to work.)



Yevgen Chupak said:


> Hey guys. I need your help.
> I have a combo of Fostex A4BL + Emotiva A100 Bas X as my external amplifier for some hard cans.
> And whenever I'm using my Shure 1540 I can hear EMI hiss A LOT (can hear much less with Senh hd600 and Shure 846). Those cans are pretty sensitive unlike my many others (Fostex, Senh, Sony, M1060 etc)
> 
> ...


----------



## KeithEmo

The Mini-X Gen2 also had the audio-on feature.
Besides the headphone output, the BasX version has a few other minor audio refinements... and should be a tiny bit quieter... but they're pretty close.



iamjaymo said:


> As mentioned, the single-ended headphone jack.  The "special" headphone feature allowing the headphones to be run at full amplifier power with the following specs:
> 
> 8 Ohms:  50 watts / channel
> 33 Ohms:  12 watts / channel
> ...


----------



## Yevgen Chupak

KeithEmo said:


> If you're hearing that sort of chortling noise that's typical of EMI, and it goes away when you disconnect the computer, or when the computer is powered down, then it's probably noise on the USB ground of the computer. The solution is to use a USB isolator. (A REAL galvanic isolator... not a noise filter type thingy like the Jitterbug. A fancy cable isn't going to help either, unless it includes a galvanic isolator. A different power supply MIGHT help - not because it's "better power", but because it's grounded slightly differently... but that's less likely to work.)



did another round of tests with MacBook Pro (on battery) instead of my mac pro as a source. Noise is still there but 20-30% less. With my LGv20 connected directly to Emotiva there is no hiss.


----------



## Yevgen Chupak

lambdastorm said:


> Did you hear any?


yep


----------



## lambdastorm

Yevgen Chupak said:


> yep


I have the 846 myself. When I hook it up to A100 the hiss I get is deafening.......take the jumpers off and everything's lovely once again......


----------



## Yevgen Chupak

Mine A100 is 5 days old so i think it's in SAFE mode still from the factory.


----------



## Shazb0t

KeithEmo said:


> Not at all......
> 
> However, even high quality Volume pots tend to have some channel imbalance down near the bottom of their range, while even low cost attenuators tend to be very precise.


I may be doing something like this as well.  I will eventually need a passive pre-amp for use with other power amplifiers that don't have a volume control.  Rather than have to buy attenuators now for the mini-X and a passive pre later I can save some money if you think that the end result is the same?  You should bring back the Control Freak so I can buy the passive pre from Emotiva!


----------



## lambdastorm

KeithEmo said:


> The Mini-X Gen2 also had the audio-on feature.
> Besides the headphone output, the BasX version has a few other minor audio refinements... and should be a tiny bit quieter... but they're pretty close.


Hey Keith, quick question. Rumor has it that Emotiva's going to release a balanced headphone amp very soon. Is it tru?


----------



## KeithEmo

lambdastorm said:


> Hey Keith, quick question. Rumor has it that Emotiva's going to release a balanced headphone amp very soon. Is it tru?



That's correct.
We have a dedicated balanced high-powered headphone amp on the way.
(No specific date yet.... but soon.)


----------



## lambdastorm

KeithEmo said:


> That's correct.
> We have a dedicated balanced high-powered headphone amp on the way.
> (No specific date yet.... but soon.)


Thanks for the info Keith. One more question: When this amp come out will it replace A100 as the go-to planar amp? And if so will it be quiet enough for IEMs (assuming it has adjustable gain)? 

Seems like you guys have your guns pointed directly at Jotunheim, which I'm not a fan of.


----------



## cavedave

This morning I had a little time to braze some 6mm solid brass spikes on the bottom of my A100 man what an up grade. I suppose you could drill
and tap some holes and replace the stock feet. Did not want to poke through and get some wires by accident. What I will say the amp was nice before now it is way nice so much weight and power in the music well worth doing.


----------



## KeithEmo (Apr 18, 2018)

The A-100 started out as a small integrated amp for driving speakers (the original Mini-X A-100 didn;t even have a headphone output).
When it became clear that people were using "speaker amps" (including the A-100) to run certain low efficiency planar headphones...
As well as certain high impedance headphones that need a lot of voltage...
And that many people preferred the way a lot of vintage equipment sounded (running their headphones from the main outputs via dropping resistors)...
We made a few modifications to allow the A-100 to fulfill those particular requirements.

As I said, I don't have all the details yet, but the new amp is going to be more like a "traditional high-end headphone amp".
It will have quite a lot of power - but not as much as the A-100 (it won't be designed to handle speakers).
I expect it to have adjustable or selectable gain, balanced and unbalanced outputs, and be able to drive any current planars and high impedance phones really well.
It will also be quiet enough to drive high-efficiency IEMs (and normal headphones) very well.

(Most modern planar headphones, while they benefit from a powerful amplifier, don't require as much power as certain few early "super inefficient" models.)



lambdastorm said:


> Thanks for the info Keith. One more question: When this amp come out will it replace A100 as the go-to planar amp? And if so will it be quiet enough for IEMs (assuming it has adjustable gain)?
> 
> Seems like you guys have your guns pointed directly at Jotunheim, which I'm not a fan of.


----------



## garbulky

I'd like to mention that amp is going to be pure class A power..... !!! I am SO tempted.


----------



## lambdastorm (Apr 18, 2018)

KeithEmo said:


> The A-100 started out as a small integrated amp for driving speakers (the original Mini-X A-100 didn;t even have a headphone output).
> When it became clear that people were using "speaker amps" (including the A-100) to run certain low efficiency planar headphones...
> As well as certain high impedance headphones that need a lot of voltage...
> And that many people preferred the way a lot of vintage equipment sounded (running their headphones from the main outputs via dropping resistors)...
> ...


Thanks again Keith, that sounds really lovely. If said amp's priced at around $400 I think I'm gonna grab one as soon as it comes out. I know there are a few amps out there that offers balanced connection but isn't internally balanced (like the massdrop THX AAA which converts balanced signal to single-ended then converts back), but since Jotunheim's fully differential and many don't like its sound signature I don't think anyone's in the position to judge a balanced amp based on whether its fully differential or not. That said tho hopefully the new Emotiva's fully differential  peace of mind.


----------



## Namtar

KeithEmo said:


> The A-100 started out as a small integrated amp for driving speakers (the original Mini-X A-100 didn;t even have a headphone output).
> When it became clear that people were using "speaker amps" (including the A-100) to run certain low efficiency planar headphones...
> As well as certain high impedance headphones that need a lot of voltage...
> And that many people preferred the way a lot of vintage equipment sounded (running their headphones from the main outputs via dropping resistors)...
> ...



I am going to hope for 10-15 watt per channel balanced.  At a low impedance of course.


----------



## lambdastorm

Namtar said:


> I am going to hope for 10-15 watt per channel balanced.  At a low impedance of course.


I hope not.......A100 at 33ohms can only do 12 watts/channel. Maybe your looking at A150?


----------



## lambdastorm

cavedave said:


> This morning I had a little time to braze some 6mm solid brass spikes on the bottom of my A100 man what an up grade. I suppose you could drill
> and tap some holes and replace the stock feet. Did not want to poke through and get some wires by accident. What I will say the amp was nice before now it is way nice so much weight and power in the music well worth doing.


Wow, that sounds fantastic! Can you tell a little more about what exactly has improved?


----------



## alpovs

Will it be truly balanced?


----------



## Namtar

lambdastorm said:


> I hope not.......A100 at 33ohms can only do 12 watts/channel. Maybe your looking at A150?



I'm dreaming of Emotiva releasing a $400 solid state balanced.amp that would compete with the mjolnir, not the jotenheim.  I suspect it will be more in line with the jot.


----------



## lambdastorm

Namtar said:


> I'm dreaming of Emotiva releasing a $400 solid state balanced.amp that would compete with the mjolnir, not the jotenheim.  I suspect it will be more in line with the jot.


That's my guess as well. Time for Emotiva to redefine 'no-compromise" & "do-it-all'!


----------



## cavedave (Apr 19, 2018)

lambdastorm said:


> Wow, that sounds fantastic! Can you tell a little more about what exactly has improved?


I guess the most I could say is just in evey way. I find putting better feet on most all audio products makes an improvement. Some times not for the best.
But mostly for the best. The feet were for speakers at first filed off the threads a little solder and a little solder on the amp a little heat to foot presto bonded.
The musical image is a lot more solid and you can hear into the music more clearly. A great little amp just a little better. Listening this morning the one word I would say is Clear the sound with the feet is super clear. clean super clear.


----------



## AxelCloris

We've removed some off-topic discussion. Please keep posts within the posting guidelines. Thanks everyone.


----------



## cavedave (Apr 22, 2018)

A picture of my A-100 at work. Not at my work at it working. Sounding mighty good.


----------



## kernel8888

got an a-100 and dc-1 up for sale if anyones interested in these!


----------



## Namtar

Ugh I wish I had the money right now XD


----------



## Baten

Just got my BasX A-100. A little late to the party. Upgrading from an Objective 2, to better drive power-hungry planar (Alpha Prime).

Mine is 100% hiss/noise free with high impedance headphones  listening now with jumpers installed, the power is INSANE lol


----------



## targetrein

Baten said:


> Just got my BasX A-100. A little late to the party. Upgrading from an Objective 2, to better drive power-hungry planar (Alpha Prime).
> 
> Mine is 100% hiss/noise free with high impedance headphones  listening now with jumpers installed, the power is INSANE lol




I did the exact same thing.  Upgraded from O2 to bas-x, upgrded to primes.  lol

I have a faint hiss on mine but it's absolutely inaudible with any music playing


----------



## Baten

targetrein said:


> I did the exact same thing.  Upgraded from O2 to bas-x, upgrded to primes.  lol
> 
> I have a faint hiss on mine but it's absolutely inaudible with any music playing



Great minds think alike? loll


----------



## targetrein

Absolutely lol - for now, this combo is my 'end-game' - I may get the itch for some of Dan's other products when the price starts to drop or I can find a set used (Ether Flow C).  

These Primes sound pretty nice and were definitely worth the upgrade from the standard Mad Dog.  The bad part is that poorly recorded music sounds even worse, now.  Guess it's time to start weeding out the old playlist...


----------



## Baten

targetrein said:


> Absolutely lol - for now, this combo is my 'end-game' - I may get the itch for some of Dan's other products when the price starts to drop or I can find a set used (Ether Flow C).
> 
> These Primes sound pretty nice and were definitely worth the upgrade from the standard Mad Dog.  The bad part is that poorly recorded music sounds even worse, now.  Guess it's time to start weeding out the old playlist...



That's weird. I find them quite forgiving actually.


----------



## bequietjk

I'm 100% I need the bas x for my t50rps


----------



## peepr

Call me crazy but I’ve been doing some intense comparison listening between my HE-560 and HD-650 on the A-100 (both from speaker taps) and I’ve found the 650 actually beats the 560 on bass. More distinct layering, feeling to the bass, greater rumble, the whole thing. I am surprised, is this because the amp is driving the 650’s to their full potential? Anyone else felt this way with this amp?


----------



## lambdastorm

peepr said:


> Call me crazy but I’ve been doing some intense comparison listening between my HE-560 and HD-650 on the A-100 (both from speaker taps) and I’ve found the 650 actually beats the 560 on bass. More distinct layering, feeling to the bass, greater rumble, the whole thing. I am surprised, is this because the amp is driving the 650’s to their full potential? Anyone else felt this way with this amp?


Did you install the jumpers?


----------



## peepr

lambdastorm said:


> Did you install the jumpers?



I have the original A-100 so straight to the speaker taps


----------



## lambdastorm

peepr said:


> I have the original A-100 so straight to the speaker taps


Oh yeah? I have the BasX, dunno how it compares with the original model but I suppose there's not much difference.
Interestingly I have HE560 and a very old HD600, which I bought in 2003 and was supposed to have more bass than white-screen HD600s in production these days. On my system the HE560 has more delicate bass and extends lower. Like other Hifiman planars it's never thumping or makes your head bob but it certainly beats my HD600 in terms of resolution and speed.

Hifiman have soft tonality IMHO. Audeze are planars as well and the LCD2 I once owned punches way harder than any hifiman I've heard.


----------



## peepr

lambdastorm said:


> Oh yeah? I have the BasX, dunno how it compares with the original model but I suppose there's not much difference.
> Interestingly I have HE560 and a very old HD600, which I bought in 2003 and was supposed to have more bass than white-screen HD600s in production these days. On my system the HE560 has more delicate bass and extends lower. Like other Hifiman planars it's never thumping or makes your head bob but it certainly beats my HD600 in terms of resolution and speed.
> 
> Hifiman have soft tonality IMHO. Audeze are planars as well and the LCD2 I once owned punches way harder than any hifiman I've heard.



I’ve not listened to LCDs but I’m curious now. I’ve read their weight can be a problem


----------



## kdoof

So I got one of these bad boys as an upgrade from my Magni 3. There is a greater noise floor from the A-100 (it is an 8 Ohm output impedance after all) so I'm thinking of keeping my Magni 3 as a pre-amp to the A-100 (to help moderate the extreme volume potential of the A-100 from my computer) and then so I can use the Magni 3 with any lower-impedance headphones I come into. Does anyone know of any drawbacks to using the Magni 3 as a pre-amp to the A-100?

As for impressions; the difference in dynamics between the two is quite palpable -- after volume matching and quickly A/Bing between the two (while using the Magni 3 as a pre-amp -- not sure if that would skew the sound or not, I can't admit to telling a difference straight from source); on my K7xx, bass is much more authoritative, meatier, the Magni 3 sounds shallow in comparison. On my HD600 everything is cleaned up, instrument separation is stronger; on ruckus-y tracks where the snare would get lost on the Magni 3, it punches right through the noise on the A-100. On my Ether Flow C's, bass slaps _haaard_ compared to the Magni 3, and the mids (my biggest beef with the Ether Flow C's is they sounded a little hollow) have much more body and weight to them.

I'm also considering selling my Magni 3 and EL DAC for a DAC/amp that can output RCA, so if anyone has any good suggestions for a product that fits that bill for around, I dunno, $250, it'd be much appreciated! (I was thinking, maybe the Aune X1s...)


----------



## Shredicus

kdoof said:


> So I got one of these bad boys as an upgrade from my Magni 3. *There is a greater noise floor from the A-100 (it is an 8 Ohm output impedance after all)* so I'm thinking of keeping my Magni 3 as a pre-amp to the A-100 (to help moderate the extreme volume potential of the A-100 from my computer) and then so I can use the Magni 3 with any lower-impedance headphones I come into. Does anyone know of any drawbacks to using the Magni 3 as a pre-amp to the A-100?
> 
> As for impressions; the difference in dynamics between the two is quite palpable -- after volume matching and quickly A/Bing between the two (while using the Magni 3 as a pre-amp -- not sure if that would skew the sound or not, I can't admit to telling a difference straight from source); on my K7xx, bass is much more authoritative, meatier, the Magni 3 sounds shallow in comparison. On my HD600 everything is cleaned up, instrument separation is stronger; on ruckus-y tracks where the snare would get lost on the Magni 3, it punches right through the noise on the A-100. On my Ether Flow C's, bass slaps _haaard_ compared to the Magni 3, and the mids (my biggest beef with the Ether Flow C's is they sounded a little hollow) have much more body and weight to them.
> 
> I'm also considering selling my Magni 3 and EL DAC for a DAC/amp that can output RCA, so if anyone has any good suggestions for a product that fits that bill for around, I dunno, $250, it'd be much appreciated! (I was thinking, maybe the Aune X1s...)



Actually the with the jumpers installed output impedance is near zero according to Keith from Emotiva. It's 220ohms with the 220ohm resistors unbypassed.


----------



## kdoof

Shredicus said:


> Actually the with the jumpers installed output impedance is near zero according to Keith from Emotiva. It's 220ohms with the 220ohm resistors unbypassed.



Ah, this is great to know! The box was missing the jumpers so I have to wait a bit to install them. Hopefully that's the case and I can sell off my Magni 3's and not worry about it.


----------



## kdoof

Shredicus said:


> Actually the with the jumpers installed output impedance is near zero according to Keith from Emotiva. It's 220ohms with the 220ohm resistors unbypassed.



Where's he say this? I've been poking around but all I've seen is people reporting greater noise floor _with_ the jumpers in, compared to without.


----------



## Shredicus (Jun 8, 2018)

kdoof said:


> Where's he say this? I've been poking around but all I've seen is people reporting greater noise floor _with_ the jumpers in, compared to without.



On page 16 of this thread:

https://www.head-fi.org/threads/emotiva-a-100.825970/page-16#post-14062849

Note that noise floor and output impedance are not directly correlated. Damping factor is determined by output impedance


----------



## kdoof

KeithEmo said:


> The A-100 started out as a small integrated amp for driving speakers (the original Mini-X A-100 didn;t even have a headphone output).
> When it became clear that people were using "speaker amps" (including the A-100) to run certain low efficiency planar headphones...
> As well as certain high impedance headphones that need a lot of voltage...
> And that many people preferred the way a lot of vintage equipment sounded (running their headphones from the main outputs via dropping resistors)...
> ...



Do you guys happen to have any idea as to approximate price point yet?


----------



## kdoof

Shredicus said:


> On page 16 of this thread:
> 
> https://www.head-fi.org/threads/emotiva-a-100.825970/page-16#post-14062849
> 
> Note that noise floor and output impedance are not directly correlated. Damping factor is determined by output impedance



Interesting, thanks for hunting this down. Yeah so far I love the quality of the sound other than the noise floor, which is a bit high and detracts from the overall experience. Disappointing to hear that it'll get even higher with the jumpers in place.


----------



## Th3Drizzl3

KeithEmo said:


> The A-100 started out as a small integrated amp for driving speakers (the original Mini-X A-100 didn;t even have a headphone output).
> When it became clear that people were using "speaker amps" (including the A-100) to run certain low efficiency planar headphones...
> As well as certain high impedance headphones that need a lot of voltage...
> And that many people preferred the way a lot of vintage equipment sounded (running their headphones from the main outputs via dropping resistors)...
> ...



Count me in im!!! happy to buy a unit. love my a100 and im guessing it will be relegated to speaker use in the kids room or my other office it depends on the output power of the new model. please keep us posted


----------



## KeithEmo

The headphone output on the A-100 is derived from the main amplifier outputs.

With the jumpers OUT (the default), there is a dropping resistor between each output and your headphone.
With the jumpers IN, those resistors are bypassed.

This means that, in general, the noise floor will be slightly higher with the jumpers in place.
However, whether that difference is slight or noticeable depends on the particular characteristics of your phones.
There may also occasionally be very unusual situations where the opposite is true.
(I would expect the increase in noise to be more significant with lower impedance headphones that are also relatively high efficiency.)



Shredicus said:


> On page 16 of this thread:
> 
> https://www.head-fi.org/threads/emotiva-a-100.825970/page-16#post-14062849
> 
> Note that noise floor and output impedance are not directly correlated. Damping factor is determined by output impedance


----------



## lambdastorm

Hey Keith,

Long time A100 user reporting in. Still pretty satisfied with what I get for $229 but I've got a new problem. A100 uses 2-prong power plug so technically it's not grounded. Not a problem for my HD600 and HD650, since as long as I turn the music up a bit it drowns out the slight hum. However my ABYSS hums loudly whenever I touch its aluminum frame. I suppose that has something to do with the headphone itself since its full aluminum construction makes the headphone conductive no matter where you touch it. But the day before yesterday I brought one of my friends over to let him try his HE6 on my A100 and to my bewilderment, HE6 hums too when I touch the headphone cup, and its not even metal, its plastic. The hum completely goes away when I put my hand on the amp, and goes back when I don't touch it. 

At this point I think its a grounding issue which would be remedied by using a 'proper' 3-prong power plug.


----------



## Shredicus

lambdastorm said:


> Hey Keith,
> 
> Long time A100 user reporting in. Still pretty satisfied with what I get for $229 but I've got a new problem. A100 uses 2-prong power plug so technically it's not grounded. Not a problem for my HD600 and HD650, since as long as I turn the music up a bit it drowns out the slight hum. However my ABYSS hums loudly whenever I touch its aluminum frame. I suppose that has something to do with the headphone itself since its full aluminum construction makes the headphone conductive no matter where you touch it. But the day before yesterday I brought one of my friends over to let him try his HE6 on my A100 and to my bewilderment, HE6 hums too when I touch the headphone cup, and its not even metal, its plastic. The hum completely goes away when I put my hand on the amp, and goes back when I don't touch it.
> 
> At this point I think its a grounding issue which would be remedied by using a 'proper' 3-prong power plug.



Interesting. I wonder if something like this would realize any sort of improvements with this amp:
https://www.amazon.com/Pangea-Audio-AC-14-Powercord-Meter/dp/B0030ERI1W/


----------



## KeithEmo

The audio circuitry in the A-100 is grounded through the analog ground - the ground connection on the RCA connectors.
This arrangement provides excellent noise performance with most systems.

(The amplifier itself is fully insulated and does not require a power safety ground.)
The chassis is actually connected to the signal ground through a resistor... so that ground is sensitive to the ground provided by your source equipment.

However, depending on how your source equipment is grounded, you can end up in the situation you describe.
If so, you could try connecting a wire between the chassis of the A-100 and some other ground.
- you could try grounding the A-100's chassis to earth ground
- you could ground the A-100's chassis to the chassis of your source component
- you could try more securely grounding the chassis of your source component to Earth ground
None of these is specifically "the most right way to do it" - but any of them may reduce or eliminate your problem.

What's basically happening in your case is that the metal of the headphones is acting as an antenna - and picking up the hum field from the air.
In different situations, the hum could get better or worse when you touch the metal, and add your body to the antenna circuit.
(Presumably, deliberately or incidentally, the shell of the headphones is electrically connected to their ground wire, or to their signal line through a capacitor.)



lambdastorm said:


> Hey Keith,
> 
> Long time A100 user reporting in. Still pretty satisfied with what I get for $229 but I've got a new problem. A100 uses 2-prong power plug so technically it's not grounded. Not a problem for my HD600 and HD650, since as long as I turn the music up a bit it drowns out the slight hum. However my ABYSS hums loudly whenever I touch its aluminum frame. I suppose that has something to do with the headphone itself since its full aluminum construction makes the headphone conductive no matter where you touch it. But the day before yesterday I brought one of my friends over to let him try his HE6 on my A100 and to my bewilderment, HE6 hums too when I touch the headphone cup, and its not even metal, its plastic. The hum completely goes away when I put my hand on the amp, and goes back when I don't touch it.
> 
> At this point I think its a grounding issue which would be remedied by using a 'proper' 3-prong power plug.


----------



## KeithEmo

We're not big fans of expecting power cables to make our equipment sound different.

However, if you look at the back of the A-100, you will see that it has a standard two-wire IEC power inlet - so that one simply won't fit.  



Shredicus said:


> Interesting. I wonder if something like this would realize any sort of improvements with this amp:
> https://www.amazon.com/Pangea-Audio-AC-14-Powercord-Meter/dp/B0030ERI1W/


----------



## Shredicus

KeithEmo said:


> We're not big fans of expecting power cables to make our equipment sound different.
> 
> However, if you look at the back of the A-100, you will see that it has a standard two-wire IEC power inlet - so that one simply won't fit.


Oops, linked the wrong one: 
Pangea Audio - AC-14 - Power Cable 1.0 Meter - C7 https://www.amazon.com/dp/B003LYCZYG/ref=cm_sw_r_cp_apa_i_xQ-hBbVAR49H3

But I see your point. Cables are a pretty contentious thing in these circles


----------



## lambdastorm

KeithEmo said:


> The audio circuitry in the A-100 is grounded through the analog ground - the ground connection on the RCA connectors.
> This arrangement provides excellent noise performance with most systems.
> 
> (The amplifier itself is fully insulated and does not require a power safety ground.)
> ...


Thanks a lot for the detailed response. I tried disconnecting the source gear today and my headphone still hums when I touch its shell, albeit not as loud. I'll take your advice and ground A100's chassis, as well as the DAC's chassis to earth ground. 

I think both the A100 and the source gear are at fault here. Right now I'm using an ifi portable DAC and its clearly not grounded: Tried plugging my ABYSS in and it hums as well. I guess the designer doesn't have low-efficiency planars in mind when he designed this DAC, cuz IEMs with plastic shell have no such problem.

Right now I'm on a family trip outside the US, and the only cable I brought is the stock one. I've got a 14AWG 2-prong cable with floating ground back home. Will try that one once I get back. 

And thanks again for all the support Keith, you never disappoint .


----------



## garbulky

lambdastorm said:


> Thanks a lot for the detailed response. I tried disconnecting the source gear today and my headphone still hums when I touch its shell, albeit not as loud. I'll take your advice and ground A100's chassis, as well as the DAC's chassis to earth ground.
> 
> I think both the A100 and the source gear are at fault here. Right now I'm using an ifi portable DAC and its clearly not grounded: Tried plugging my ABYSS in and it hums as well. I guess the designer doesn't have low-efficiency planars in mind when he designed this DAC, cuz IEMs with plastic shell have no such problem.
> 
> ...


First if you have your A-100 with the resistors bypassed (jumpers engaged) then this is the wrong setting for high efficiency IEM. 
As for the ground, have you tried the RCA ground loop isolator? They are between 7 and 10 bucks and are designed to get rid of of a ground loop buzz. 
Search Amazon for ground loop isolator and youll find quite a bit
They look like this


----------



## lambdastorm

garbulky said:


> First if you have your A-100 with the resistors bypassed (jumpers engaged) then this is the wrong setting for high efficiency IEM.
> As for the ground, have you tried the RCA ground loop isolator? They are between 7 and 10 bucks and are designed to get rid of of a ground loop buzz.
> Search Amazon for ground loop isolator and youll find quite a bit
> They look like this


I haven't looked into groundloop isolator yet, will try it once I get back to the US. 

I get a few keks out of the IEM thing. My bad for not explaining. The ifi DAC I mentioned is a Micro iDSD BL, it has a mighty powerful headphone amp built-in and I use it for all headphones that gets too loud on the A100, including my trusty IEMs.


----------



## owatito

KeithEmo said:


> Absolutely...
> 
> The HD650 is 300 Ohms, so it's perfectly safe to run them on the A-100 with or without the jumpers.




Hello KeithEmo,  I think this product is fantastic, how safe is it with the akg k712 pro? (62 ohms), taking into account that the jumpers would be connected.  I have a Akg k340 electrostatic-dynamic, with 400 ohms, according to the same AKG, were recommend connected directly to a speaker amplifier, I am very curious how they can sound on the A-100.

I'm sorry for my bad English.

 Greetings.


----------



## KeithEmo

Any questions of safety are actually quite simple - but they can still be confusing.

The power going to the headphones is coming from the output of a very powerful amplifier designed to power speakers.
With the jumpers OUT, there is a 220 Ohm resistor connected between the output of the amplifier and the headphone.
With the jumpers IN, the output of the amp is connected directly to the headphones.

First off, with any headphones whose manufacturer recommends connecting them directly to a speaker amplifier, JUMPERS IN is the best option, and is perfectly safe.
With the JUMPERS IN you are connecting the headphones directly to the amplifier - as recommended.
(Of course, you do still need to exercise some care.... it would be possible to burn out any headphone if you turn the amp up too far - but your ears will probably be bleeding long before then.)

With other headphones, how the jumpers act will depend on the impedance of the headphones.

For example, if you have 300 Ohm headphones, the 220 Ohm resistor reduces the voltage reaching the headphones by about 40%.
These headphones require a relatively high drive voltage, so they'll work well on the A-100, and they'll only be a little bit louder if you install the jumpers (something like 2 dB louder).

HOWEVER, the lower the impedance of your headphones, the more effect the resistor will have.
For example, with 62 Ohm headphones...... the resistor in the A-100 will have a much more significant effect.
With 62 Ohm headphones, and with the A-100 playing at the same loudness, the headphones will receive _16 TIMES_ as much power with the JUMPERS IN as with the JUMPERS OUT.
This isn't specifically dangerous, but it means that you will have to set the volume on the A-100 MUCH lower with the jumpers in to reach similar loudness.
It also means that, if your 60 Ohm headphones were playing loudly without the jumper, by putting in the jumper you might risk burning them out - or hurting your ears.
It also means that, depending on the level of your signal source, and the efficiency of your headphones, the noise floor of the A-100 might be audible, and you might simply have trouble adjusting the volume control carefully enough.

The main danger is that, WITH THE JUMPERS IN, if you set the A-100 to play at a comfortable level with high impedance headphones, and you then plug in low impedance ones without adjusting anything, they will be VERY LOUD.

In your case, the A-100 will work great with your k340's with the JUMPERS IN (and probably won't work very well with the jumpers out).
It will also work great with your K712's with the jumper OUT.
However, with the jumpers IN, you might notice some noise with the K712's, and you may barely be able to move the volume control before they get really loud.

But the big DANGER is that, if you have the JUMPERS IN, and you're playing the A-100 with the k340's, then you plug in the k712's without remembering to turn the A-100 all the way down first, you may fry the K712's.



owatito said:


> Hello KeithEmo,  I think this product is fantastic, how safe is it with the akg k712 pro? (62 ohms), taking into account that the jumpers would be connected.  I have a Akg k340 electrostatic-dynamic, with 400 ohms, according to the same AKG, were recommend connected directly to a speaker amplifier, I am very curious how they can sound on the A-100.
> 
> I'm sorry for my bad English.
> 
> Greetings.


----------



## owatito

KeithEmo said:


> Any questions of safety are actually quite simple - but they can still be confusing.
> 
> The power going to the headphones is coming from the output of a very powerful amplifier designed to power speakers.
> With the jumpers OUT, there is a 220 Ohm resistor connected between the output of the amplifier and the headphone.
> ...




Wonderful and very interesting explanation, thank you very much for your time to answer my question, I am very clear that I must and should not do with my headphones.

Excellent day KeithEmo


----------



## Th3Drizzl3

hey keithemo any ballpark timeframe for that new model? I'm hanging onto my a100 until then of course but I'm curious


----------



## PopZeus

Love this amp paired with the Elac UB5.


----------



## Namtar

I couldn't take it anymore.   Just ordered my A100 from Emotiva.    
Tentative setup will be PC -> Marantz SR7100 (sadly I have to use 3.5mm to RCA instead of Optical out - the receiver won't act as a DAC and output analog from a digital source) -> A100 for headphones.    The receiver will be the preamp so I can have some volume control on the A100.

The main headphones will be my Massdrop HE-4XX.  
And now my wife can get the Magni 2U when she decides to go for good headphones instead of her gaming headset!

I'll post back with comparisons between the A100 & Marantz headphone jack when I'm able.


----------



## garbulky

Namtar said:


> I couldn't take it anymore.   Just ordered my A100 from Emotiva.
> Tentative setup will be PC -> Marantz SR7100 (sadly I have to use 3.5mm to RCA instead of Optical out - the receiver won't act as a DAC and output analog from a digital source) -> A100 for headphones.    The receiver will be the preamp so I can have some volume control on the A100.
> 
> The main headphones will be my Massdrop HE-4XX.
> ...


Go get you a cheap USB DAC! You'll thank yourself. You can have them for between $30 and $100


----------



## Namtar

garbulky said:


> Go get you a cheap USB DAC! You'll thank yourself. You can have them for between $30 and $100



I'm still unsure if I'm going to go the USB route -  I've had bad luck with them in the past.  I'm honestly good with 24/96 coming from the PC out since I'm sure most of the video games I play aren't using audio mastered in anything higher. 
Long term I'm going to probably save up for a bit and get a Topping D50 -  or I might go all out and get the DX7s so that later on I can go balanced as I get back into the headphone / audio game.  Regardless of what I choose, I want my DAC to have volume control so it can act as a preamp.   (and long term balanced headphone amp will be something along the lines of a Mojo2


----------



## Mightygrey

Namtar said:


> I'm still unsure if I'm going to go the USB route -  I've had bad luck with them in the past.  I'm honestly good with 24/96 coming from the PC out since I'm sure most of the video games I play aren't using audio mastered in anything higher.
> Long term I'm going to probably save up for a bit and get a Topping D50 -  or I might go all out and get the DX7s so that later on I can go balanced as I get back into the headphone / audio game.  Regardless of what I choose, I want my DAC to have volume control so it can act as a preamp.   (and long term balanced headphone amp will be something along the lines of a Mojo2


Emotiva have been threatening to release a DC-2 balanced dac soon that ought to do many of these things...


----------



## Namtar

First impressions are VERY positive.   Listening to some of my "usual" youtube music -  the bass on my headphones has really tightened up and it's not muddy.   This amp exercises a LOT of control over my cans.


----------



## garbulky

Namtar said:


> First impressions are VERY positive.   Listening to some of my "usual" youtube music -  the bass on my headphones has really tightened up and it's not muddy.   This amp exercises a LOT of control over my cans.


You might like this DAC. A cheap low cost alternative to an in built sound card. 
Behringer UCA 202. $30


----------



## bequietjk

Super tempted in grabbing up this A-100.  I remember when the Mini-X was out and I was drooling over it's passive speaker/headphone capability.  Plus the overall build of the amp looks super clean, especially the blue ring.


----------



## Rchandra

So I just purchased my unit and I have a ton of background noise with jumpers installed using my hd800S and focal elears. It's such a great amp but the noise floor is ridiculous. Now I see some people saying their is no background noise and some like me saying their clearly is. Has anyone been able to get rid of that background hiss?


----------



## Baten

Rchandra said:


> So I just purchased my unit and I have a ton of background noise with jumpers installed using my hd800S and focal elears. It's such a great amp but the noise floor is ridiculous. Now I see some people saying their is no background noise and some like me saying their clearly is. Has anyone been able to get rid of that background hiss?



I fear it's unit to unit variance not unexpected in this $220 price range :/


----------



## Mightygrey

Rchandra said:


> So I just purchased my unit and I have a ton of background noise with jumpers installed using my hd800S and focal elears. It's such a great amp but the noise floor is ridiculous. Now I see some people saying their is no background noise and some like me saying their clearly is. Has anyone been able to get rid of that background hiss?


It's a case-by-case basis for me - it's clearly audible on my ZMF Eikons, both with and without jumpers installed. Perfectly quiet on my Grados (GH1) and Senn HD650's.


----------



## Rchandra

Mightygrey said:


> It's a case-by-case basis for me - it's clearly audible on my ZMF Eikons, both with and without jumpers installed. Perfectly quiet on my Grados (GH1) and Senn HD650's.



Perhaps its headphones and not the amp? But in this instance a hd800S shouldn't have any background noise at all. I'm disappointed


----------



## Rchandra

Baten said:


> I fear it's unit to unit variance not unexpected in this $220 price range :/



I'm afraid you might be right


----------



## garbulky (Jul 23, 2018)

Rchandra said:


> So I just purchased my unit and I have a ton of background noise with jumpers installed using my hd800S and focal elears. It's such a great amp but the noise floor is ridiculous. Now I see some people saying their is no background noise and some like me saying their clearly is. Has anyone been able to get rid of that background hiss?


Try using it without the jumpers installed. You should hear no hiss then.  With jumpers installed, for the focal elears I think hiss is to be expected at 80 ohms as that provides a lot of power through. With the 800S @ 300 ohms you shouldn't be getting a ton of hiss as you described. It should be a soft but slightly audible hiss during silence which you don't hear when music plays. I suspect cabling issues or some sort of ground loop upstream. Is it a USB powered DAC? Could be dirty power.

I doubt it's unit variance. It shouldn't vary that much. Maybe you got a bad unit. If the noise goes completely away without jumpers, then it's probably normal and may be quiter with a different unit and cable upstream. If the noise doesn't go away without jumpers then there is likely a problem.


----------



## Rchandra

garbulky said:


> Try using it without the jumpers installed. You should hear no hiss then.  With jumpers installed, for the focal elears I think hiss is to be expected at 80 ohms as that provides a lot of power through. With the 800S @ 300 ohms you shouldn't be getting a ton of hiss as you described. It should be a soft but slightly audible hiss during silence which you don't hear when music plays. I suspect cabling issues or some sort of ground loop upstream. Is it a USB powered DAC? Could be dirty power.
> 
> I doubt it's unit variance. It shouldn't vary that much. Maybe you got a bad unit. If the noise goes completely away without jumpers, then it's probably normal and may be quiter with a different unit and cable upstream. If the noise doesn't go away without jumpers then there is likely a problem.



I might try some new rca cables maybe audio quest and see if it changes anything


----------



## Shredicus

No hiss here with jumpers installed on my: T50rp argon, Hd58x, hd6xx, dt880 600ohm, Philips SHL3300. I can only produce hiss with a paused track with volume turned beyond 90% on my most sensitive IEMs, Tin Audio T2, KZ ZS6.


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## Mightygrey

Rchandra said:


> Perhaps its headphones and not the amp? But in this instance a hd800S shouldn't have any background noise at all. I'm disappointed


I'm borrowing a friend's HD800S's tomorrow so I'll let you know how that works out for me.


----------



## Rchandra

Mightygrey said:


> I'm borrowing a friend's HD800S's tomorrow so I'll let you know how that works out for me.



Appreciate that brother.


----------



## kdoof

I also had a fair amount of noise floor with my HD600's -- which isn't really supposed to happen. So I returned mine. (It was a factory refurbished unit so I wonder if that was the issue the first owner had had as well)


----------



## Rchandra

I contacted customer service they said a technician would get in touch with me, and so far they haven't. I sent them a copy of my receipt since they requested it. I'll keep you guys posted. But so far customer service is wack


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## Th3Drizzl3

i had an issue with the first once i received. there was a good scratch on the front and a small dent in it. i called them and they handled it asap. i had a new one shipped out as soon as they saw the tracking number was moving back to them. i suggest calling if you dont get a email response timely. they were great to deal with.


----------



## Rchandra

Th3Drizzl3 said:


> i had an issue with the first once i received. there was a good scratch on the front and a small dent in it. i called them and they handled it asap. i had a new one shipped out as soon as they saw the tracking number was moving back to them. i suggest calling if you dont get a email response timely. they were great to deal with.



Thanks that is great to hear


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## Rchandra

I just think what weirds me out is the 50/50 of people saying that their is noise and people saying their isnt


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## Th3Drizzl3

could it be a ground issue or induced noise from something close by? just thinking out loud


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## Rchandra

Th3Drizzl3 said:


> could it be a ground issue or induced noise from something close by? just thinking out loud



I'm not sure brother but I'm hoping I can figure it out soon I might try audio quest rcas and see if cables help


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## Th3Drizzl3

i would also try moving it to a different room just for the heck of it. i know a number of people with the a100 and no one has mentioned this type of noise. but its worth a shot. is it a hiss, hum, buzzing, etc etc what does the noise sound like? like old school tape hiss?


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## Mightygrey

It's like b


Th3Drizzl3 said:


> i would also try moving it to a different room just for the heck of it. i know a number of people with the a100 and no one has mentioned this type of noise. but its worth a shot. is it a hiss, hum, buzzing, etc etc what does the noise sound like? like old school tape hiss?


It's just a low, consistent noise that doesn't go 'up' with volume. It's like being able to hear an air-conditioner that's on in another room while wearing headphones.


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## Th3Drizzl3 (Jul 23, 2018)

the only time i have heard anything on mine hiss wise is with a track paused and the volume up past where it ever should be imo. also my hd800's are quiet no hissing or humming jumpers either way unless turned way up with no signal. generally if its like a hiss then its prob not a ground noise. thats usually a hum, buzz, or like a whine. def possible to get a dud sadly. only other thing i can think of is the source. either material or actual device. have you tried with something other then that? again just a shot.


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## garbulky

Rchandra said:


> I'm not sure brother but I'm hoping I can figure it out soon I might try audio quest rcas and see if cables help


 In case I wasn’t clear, I don’t think expensive cables will make the sound less hissy.  But perhaps your current cable might be damaged. But I think that’s a low likelihood.


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## Mightygrey

garbulky said:


> In case I wasn’t clear, I don’t think expensive cables will make the sound less hissy.  But perhaps your current cable might be damaged. But I think that’s a low likelihood.


I'm using a brand-new Audioquest 3.5mm > RCA cable to feed mine. It's definitely nothing to do with cables...


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## Rchandra

So I hope this helps anyone but emotiva responded to me and they said that yes that noise floor is supposed to be their. Especially with the jumpers installed which is one of the reasons why they ship without the jumpers installed... So it looks like it is supposed to be there according to emotiva  hope this helps.


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## Rchandra

So now the people that say they don't get any floor noise. I wonder if they are just trolling when emotiva themselves say that their is supposed to be floor noise with the jumpers because of all the power lol


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## garbulky (Jul 24, 2018)

Rchandra said:


> So I hope this helps anyone but emotiva responded to me and they said that yes that noise floor is supposed to be their. Especially with the jumpers installed which is one of the reasons why they ship without the jumpers installed... So it looks like it is supposed to be there according to emotiva  hope this helps.


When the jumpers are installed the noise floor increases by a huge degree. About 100x or something. So it's not unheard of to have a noise floor. however your headphones are 300 ohms, so unless a tiny bit of hiss (with the HD800) really bothers you, it doesn't sound normal if it's super loud.

What I'm trying to say is it's hard to say what somebody would consider "really loud hiss". For others really loud may simply mean there is some hiss that exists. So Emotiva takes the factual route and confirms that things can be noisy with the wrong headphone paired.In your case your 300 ohm headphones are the "right" headphones. 
IF the noise floor goes away with jumpers, then it is normal. If it doesn't go away with jumpers then it is abnormal.


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## Th3Drizzl3

Rchandra said:


> So now the people that say they don't get any floor noise. I wonder if they are just trolling when emotiva themselves say that their is supposed to be floor noise with the jumpers because of all the power lol


There of course is some noise with the jumpers. But not a ton on my unit. It's a faint hiss its not all crazy loud. Not what i would call loud anyway knowing the way the amp works. But without them it's silent. Owned my unit since the beginning of the year. I think what some think of as noise is not the same as others. If u are hearing a huge amount of noise then something might be wrong. The noise is much more noticeable as I said without a source and the volume way up.


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## sanvara

I concur. Using jumpers here and hiss is very minor with HE560 and HD650 headphones.


----------



## KeithEmo

Every electronic amplifier in the world has a noise floor... although the noise floor is much lower on some pieces of equipment than on others.
Compared to other "speaker amplifiers", the A-100 is exceptionally quiet.
However, when compared to other headphone amplifiers, while it is far more powerful than most, it is about average in terms of noise floor.
Some headphones are more sensitive than others, some boost high frequencies more than others, and some people are more sensitive to noise than others.
(Both vinyl and magnetic tape have noise floors which some people find highly objectionable - while others don't notice them at all.)

When the A-100 is connected to headphones of average efficiency, the noise floor should be very low, but might still be audible.
With very high efficiency headphones, it may be more noticeable, and some people may even find it objectionable.
The noise floor will always be slightly higher when the jumpers are inserted - but the difference will depend on the specific headphones connected to it.

The noise floor of the A-100 itself should be relatively innocuous white noise (hiss), which shouldn't vary much when you raise and lower the A-100's Volume setting.
If you hear a significant amount of hiss, and it raises and lowers with the A-100's Volume setting, then it's probably due to the noise floor of your source component.
And, if you hear a significant amount of hum, or other types of noise, then it's probably due to a ground loop, or some other type of external noise source.
(And, with any amp, including the A-100, if you hear a noise like sizzling bacon, even with nothing connected to the input, then it may indicate a hardware problem with the amp.)



Th3Drizzl3 said:


> There of course is some noise with the jumpers. But not a ton on my unit. It's a faint hiss its not all crazy loud. Not what i would call loud anyway knowing the way the amp works. But without them it's silent. Owned my unit since the beginning of the year. I think what some think of as noise is not the same as others. If u are hearing a huge amount of noise then something might be wrong. The noise is much more noticeable as I said without a source and the volume way up.


----------



## Rchandra

I really truly appreciate everyone's feedback on this. You guys are awesome I hope you all have an amazing week. It was nice getting responses from everyone.


----------



## Yevgen Chupak

My Emotive producing really low noise... even with IEMs Shure 846 i can hear that bg hiss only almost at full tilt. So this could be still faulted unit.


----------



## Th3Drizzl3

KeithEmo said:


> Every electronic amplifier in the world has a noise floor... although the noise floor is much lower on some pieces of equipment than on others.
> Compared to other "speaker amplifiers", the A-100 is exceptionally quiet.
> However, when compared to other headphone amplifiers, while it is far more powerful than most, it is about average in terms of noise floor.
> Some headphones are more sensitive than others, some boost high frequencies more than others, and some people are more sensitive to noise than others.
> ...



i totally agree with what you said. one thing is without any source hooked up you can hear the "hiss" rise in volume as you turn the knob. while like i said its not at all drastic it does vary some depending on how high the knob is. and when i say cranked i mean no source and turn the knob literally almost all the way up. then there is a bit more noticeable hiss. as i turn it down and hit say three o clock it starts to become almost gone. once around say 10-11 i really barely hear anything. and im talking about with the jumpers installed. without them like i said its almost not even noticeable.


----------



## Rchandra

Th3Drizzl3 said:


> i totally agree with what you said. one thing is without any source hooked up you can hear the "hiss" rise in volume as you turn the knob. while like i said its not at all drastic it does vary some depending on how high the knob is. and when i say cranked i mean no source and turn the knob literally almost all the way up. then there is a bit more noticeable hiss. as i turn it down and hit say three o clock it starts to become almost gone. once around say 10-11 i really barely hear anything. and im talking about with the jumpers installed. without them like i said its almost not even noticeable.



Do you mean with music playing or no music playing because with me if their is music playing then it goes away after a while but if no music is playing I can hear it


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## Th3Drizzl3

with no source. so powered on and headphones in but no rca or usb etc no music coming into it at all. and those cables disconnected.


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## KeithEmo

We need to make a distinction here about what we mean when we say "no source".
Do you mean "the disc is playing but we're between tracks" or do you mean "the disc is stopped" or "the disc player is turned off" or "the cables are actually unplugged from the input connectors on the A-100"?

The circuitry inside the BasX A-100 is connected together pretty much the same way that analog integrated amplifiers usually are (digital processors usually use a different topology):
In the A-100, the actual amplifier section has a fixed gain.
This means that the signal being fed to the amp is always boosted by the same amount, and the noise floor on the amp itself pretty much doesn't change.
The Volume control reduces the level of the input signal - using a passive voltage divider (a potentiometer).
Being passive, the potentiometer adds no noise to the signal.

Therefore, assuming there is nothing physically connected to the input, we would expect the noise floor at the output to be the actual noise floor of the amplifier circuitry itself.
And, in principle, that noise floor would be exactly the same no matter where we set the Volume control.
There's nothing coming into the input, so it doesn't matter how much we divide down that nothing; the Volume control itself adds no noise; so all we're hearing is the inherent noise as the amplifier "amplifiers nothing".
In practice, this isn't exactly true, because, like most amplifiers, the A-100 is a tiny bit quieter when the input is actually shorted, as opposed to almost shorted, but the difference is only a few dB.

Likewise, at least in theory, if we connect a CD player to the input, but it is actually powered off, we would expect it to be "providing a zero input", and we would expect the same situation.
Again, in practice, the extra wire hanging on the input could pick up a little noise like an antenna, and the output of the CD player might not be a very good shot.
However, for the most part, we would still expect to be hearing pretty much only the noise floor of the A-100, which should be very low, and shouldn't change when we change the Volume setting.
(And, if there is some noise, and it DOES change significantly when we change the Volume setting, then we can assume it's coming in from the wire - perhaps due to a ground loop.)

Now, lets turn the power on to our CD player (or other source).
At this point, our source is now active, so we would expect to be hearing the noise floor of its output circuitry, being amplified by the A-100.
Some devices have a lower noise floor than others, and some actually ground the output when there's no music playing, but others do not.
If you notice more noise when the source component is turned on, and that noise level changes when you change the Volume on the A-100, then you're hearing the noise floor of your source component.

The same holds true if what we've got connected to the A-100 is a preamp, or the output of a smart phone, or the output of a DAC.
If the noise floor jumps up when you turn it on, and varies when you change the Volume setting on the A-100, then you're hearing the noise floor of your source.

Now let's actually press PLAY - or start playing our digital file - or whatever.
If the noise increases at this point, it could actually be due to one or both of two different things.
We could be hearing the background noise on our actual source file, or CD, or other input source.
This noise is going to go up and down when we turn the Volume control on the A-100 up and down.
It could also vary for all sorts of other reasons.... depending on the content itself....
- the noise could drop between tracks - or not
- it could even rise and fall during an individual track (as an artifact of how the track is mixed)

The other thing is that many devices, especially some digital devices like CD players and DACs, actually "sense silence"....
When the music stops, perhaps between tracks, they actually mute their output.
Therefore, a split second after the music stops, they basically switch off their outputs - and get real quiet.
(Because of this feature, you may notice that the silence between tracks is quieter on some players than on others.)

And, finally, it's worth remembering that the noise floor is additive....
What you hear is the sum total of all the noise floors of all the devices the signal is passing through.
Although you often only notice the noise floor of whichever component happens to be the noisiest - that may change depending on what's going on at the time.
(However, if you want to confirm what part of it is the noise floor on the A-100 itself, the only real way to do that is to disconnect the input cables from the A-100 itself.)



Th3Drizzl3 said:


> i totally agree with what you said. one thing is without any source hooked up you can hear the "hiss" rise in volume as you turn the knob. while like i said its not at all drastic it does vary some depending on how high the knob is. and when i say cranked i mean no source and turn the knob literally almost all the way up. then there is a bit more noticeable hiss. as i turn it down and hit say three o clock it starts to become almost gone. once around say 10-11 i really barely hear anything. and im talking about with the jumpers installed. without them like i said its almost not even noticeable.


----------



## KeithEmo

In that case, you should be hearing just the noise floor on the A-100... and it should change very little with the position of the Volume control.



Th3Drizzl3 said:


> with no source. so powered on and headphones in but no rca or usb etc no music coming into it at all. and those cables disconnected.


----------



## KeithEmo

It's also worth remembering that our ears have a sort of built-in automatic gain control... and it is actually remarkably effective.
When things get quiet, the sensitivity of our hearing gets boosted by a significant degree, and continues to boost even more with time.
There is an actual mechanism that adjusts the sensitivity of our ears themselves based on the average sound level.
This is why things sound real quiet for a few minutes after you turn off the lawn mower.
However, there is another mechanism that occurs in our brain itself, which causes us to stop noticing steady continuous noises - like amplifier hiss and your air conditioner.
These two mechanisms operate together - and sometimes produce interesting results.

You finish mowing the lawn and everything seems quiet for several minutes...
Then things return to normal...
Then the air conditioner turns on, and you notice the sound it makes for several minutes...
But, after a while, you stop noticing it - because you "become used to it".
(And also because, since the noise level has now bumped up a bit, the sensitivity of your ears drop somewhat again.)

In the case of listening to music, you tend not to notice the noise floor while the music is playing, because the music is much louder.
Then, after the music stops, and the sensitivity of your ears cranks up, you start noticing the noise floor.
Then, often, some minutes later, you again stop noticing the noise floor "because you get used to it".

It can be interesting to get yourself a sensitive SPL meter and see how the actual sound level correlates to what you _THINK_ you hear 



Rchandra said:


> Do you mean with music playing or no music playing because with me if their is music playing then it goes away after a while but if no music is playing I can hear it


----------



## Th3Drizzl3

KeithEmo said:


> In that case, you should be hearing just the noise floor on the A-100... and it should change very little with the position of the Volume control.


keithemo please note i love mine and im totally happy with it. ive known the noise was normal sine i got it. just want to make sure you know i was simply trying to explain that to the other couple people saying they had noise.


----------



## KeithEmo

Absolutely - and I'm glad you're enjoying it.... which is, after all, what really counts here.

I just have a feeling that a lot of people have very different expectations... and even a few different ideas about what noise floor is - and where it comes from.
The A-100 is not, and never will be, the quietest headphone amp on the planet.... that's not it's strength....  but we've had very few actual defective ones come back. 



Th3Drizzl3 said:


> keithemo please note i love mine and im totally happy with it. ive known the noise was normal sine i got it. just want to make sure you know i was simply trying to explain that to the other couple people saying they had noise.


----------



## garbulky

KeithEmo said:


> Absolutely - and I'm glad you're enjoying it.... which is, after all, what really counts here.
> 
> I just have a feeling that a lot of people have very different expectations... and even a few different ideas about what noise floor is - and where it comes from.
> The A-100 is not, and never will be, the quietest headphone amp on the planet.... that's not it's strength....  but we've had very few actual defective ones come back.


I say for the right headphones, this is really a very good amplifier. It's the sense of ease with dynamics that it shines. I hope your upcoming class A balanced amp will sound as good.


----------



## Askilla

I have one paired with Hifiman he-400i modded with flat cottonpads(I think the pads are made for ecigg) between the driver and ear. I also have angled hm5 pleater pads on them. 
Sounds amazing in full power mode, with lots of room to adjust the volume. 
I can barely hear the noise floor and it does not get any louder if I turn upp the the volume.
I am using aune x1s as dac.

I am truly in Love with this amp, thank you Emotiva!


----------



## Heavyboxer

I am interested in purchasing a unit for not just my headphones (6xx, 4xx and lcd-2) but also for a pair of bookshelf speakers, either the Elac debut 6.2 or dynaudio m20.

Questions:

1. Would this amp be a good match for either/or speakers?

2. Can I have the headphone plugged in while I play tunes on the speakers? I know this isn't normal, but i foresee myself forgetting to unplug often. 

3. Which side can I have it stand on for minimal heat issues, since I have limited desk space and initially planned to place the R2R-11 on top (with little spacers so the vents are still functional)?

4. Can I order the amp with the jumpers in place and have noise floor checked and passed as acceptable Emotiva QC levels before it gets shipped to me 10,000 miles away? If additional costs are involved, I would be happy to pay.

Hope someone from Emotiva can answer some, if not all my queries.


----------



## Povell42 (Aug 30, 2018)

So Amazon says they are not available due to a problem with their stock.  Anyone have any idea what is going on, or when they will be available to buy again?
Oh, and has anyone use the BasX with an Audeze LCD3?


----------



## vormhat

KeithEmo said:


> Absolutely - and I'm glad you're enjoying it.... which is, after all, what really counts here.



Wow, I think I need this amp.  This would be my second Emo product.  My first Emo product was basically the first amp you guys ever sold back at av123.com, the almighty LPA-1 which I still use to this day!


----------



## garbulky

Heavyboxer said:


> I am interested in purchasing a unit for not just my headphones (6xx, 4xx and lcd-2) but also for a pair of bookshelf speakers, either the Elac debut 6.2 or dynaudio m20.
> 
> Questions:
> 
> ...


 
1. WIthin its 50 watts of output, yes it does fine with speakers. I've drive Axiom m80 tower speakers with them and they didn't lack composure.. However note that 50 watts is 50 watts so I don't know how hard you plan to push them. But for me, since I live in a small room, I thought its power output was adequate. Most of the time one is listening at about 1 to 2 watts of power. 
2. I don't know. I don't think so. The good news is that it's okay if you forget, as you'll remember because the sound is off  
3. The best way is to stand it like it is pictured. There are vents on the side and top. However the amp produces very little heat. You have to leave at least a small gap though for air flow on the three sides. 
4. I doubt it. I mean, maybe, you are going to want to call Emotiva and find out. But it's not super hard to do. All you need is a screwdriver.


----------



## MyPants

Yeah for what it's worth, it took me like ten minutes to put the jumpers in, and most of that was removing and then reinstalling the case screws.


----------



## Povell42

Just got my Emotiva Basx A-100.  So far so good.  If I don't have it plugged into a power cleaner it has some humming noise even on zero volume.


----------



## Heavyboxer

Povell42 said:


> Just got my Emotiva Basx A-100.  So far so good.  If I don't have it plugged into a power cleaner it has some humming noise even on zero volume.



Nice!
Power cleaner = power conditioner?
Please post a photo as I'd like to be prepared for any unwanted noise.


----------



## Povell42 (Sep 6, 2018)

Heavyboxer said:


> Nice!
> Power cleaner = power conditioner?
> Please post a photo as I'd like to be prepared for any unwanted noise.






This is the one I am using at my home desk.  I actually brought the a-100 to work to use it for the day. At work is where I noticed the hum. I had it plugged into a crappy power strip which gave a noticeable hum, and then i tried plugging directly into the wall at work and the hum went down in volume significantly, but is still there.

I will bring it home tomorrow and plug it back into my panamax power cleaner to see if there is any audible hum in absolute silence. I am sure most power cleaners will work just fine... no need to get the expensive one I have. This will also depend on the ohm of your headphone.  The LCD3 is 110 ohm. The higher the ohm of the headphone should equate to less background noise on this beast of a headamp.

Edit: The hum is increased wiith the DAC plugged into dirty power too.  Last night I listened to it at home for a little bit, and it does have hiss/hum with you turn the volume up all the way with nothing playing.  (*this is for the headphone out... I have not tested it on speakers yet, but don't think it will be audible with speakers.)


----------



## Heavyboxer

Interesting.... 

I actually need a neat power strip that's in the form of a rack power conditioner...

I take dirty and clean power as a bit of snake oil, since I tried them previously on my big home setup as the salesman brought it as demo and heard absolutely no difference...but everyone's mileage may vary.


----------



## greenkiwi

Heavyboxer said:


> I am interested in purchasing a unit for not just my headphones (6xx, 4xx and lcd-2) but also for a pair of bookshelf speakers, either the Elac debut 6.2 or dynaudio m20.
> 4. Can I order the amp with the jumpers in place and have noise floor checked and passed as acceptable Emotiva QC levels before it gets shipped to me 10,000 miles away? If additional costs are involved, I would be happy to pay.
> 
> Hope someone from Emotiva can answer some, if not all my queries.



@Heavyboxer  I suggest that you reach out over the phone for this.  They are very responsive.



garbulky said:


> 1. WIthin its 50 watts of output, yes it does fine with speakers. I've drive Axiom m80 tower speakers with them and they didn't lack composure.. However note that 50 watts is 50 watts so I don't know how hard you plan to push them. But for me, since I live in a small room, I thought its power output was adequate. Most of the time one is listening at about 1 to 2 watts of power.
> 2. I don't know. I don't think so. The good news is that it's okay if you forget, as you'll remember because the sound is off
> 3. The best way is to stand it like it is pictured. There are vents on the side and top. However the amp produces very little heat. You have to leave at least a small gap though for air flow on the three sides.
> 4. I doubt it. I mean, maybe, you are going to want to call Emotiva and find out. But it's not super hard to do. All you need is a screwdriver.


@garbulky Great to see you over here.


----------



## sanvara

Povell42 said:


> Just got my Emotiva Basx A-100.  So far so good.  If I don't have it plugged into a power cleaner it has some humming noise even on zero volume.



The Schiit Modi and the A-100 is a good combo. What took things up yet another notch for me was adding the Schiit Loki to the chain.


----------



## Heavyboxer

greenkiwi said:


> @Heavyboxer I suggest that you reach out over the phone for this. They are very responsive



I would, but then I'd have to stay up the night to call during their office hours.
Anywayl, ended up purchasing the R-28 from Audio-gd.

But if I purchase passive bookshelf speakers again, I will be looking into this amp once more.


----------



## Povell42

So, I brought the A-100 home tonight and discovered that when my home office is quite, there is still a small audible noise floor with the LCD3.  This is with no source plugged in, and power plugged into the Paramax power source.     This kinda bugs me.  I have been comparing my Aune X7s back and forth with volume matching and I am having a difficult time discerning difference.... other than the A-100 gets louder much quicker.  I am also finding myself listening to higher than usual volumes with the A-100. It does make it sound more alive, but when I swap to the Aune x7s I realize just how high of volume it is on the A-100 compared to my usual listening volume. 

I think this is a obviously a better amp paired with 300 ohm + headphones(such as HD600, 650, 6xx, HD800).  That ohm rating would probably eliminate any audible noise floor. I am mainly on a venture to find the right amp to pair with my LCD3... and I don't think the A-100 is the "end" amp for it.


----------



## TheAnalogman

If I bought a splitter to connect to the headphone jack (so da wife and myself can listen together), would this work? Does anyone know how the output specs would change? Power, impedance etc? With and without the jumpers installed? I'm looking at driving 2 HE560s. Thanks


----------



## Heavyboxer

TheAnalogman said:


> If I bought a splitter to connect to the headphone jack (so da wife and myself can listen together), would this work? Does anyone know how the output specs would change? Power, impedance etc? With and without the jumpers installed? I'm looking at driving 2 HE560s. Thanks



I would imagine the ohm would double and output will decrease by half?


----------



## garbulky

Heavyboxer said:


> I would imagine the ohm would double and output will decrease by half?


I thought the impedance will drop by half. If you try it, try it first with the resistors engaged (jumpers disengaged)


----------



## Heavyboxer

garbulky said:


> I thought the impedance will drop by half. If you try it, try it first with the resistors engaged (jumpers disengaged)



Oh you're right, just remembered how I wired my dual subs in my car long, long ago...


----------



## KeithEmo

When you connect two identical headphones to the same output with a passive splitter (y-cable).....
The LOAD IMPEDANCE will be halved.

How this affects the output of the amp will depend on whether you have the jumpers in or not.

IF YOU HAVE THE JUMPERS IN....
There will be virtually no effect on the power that reaches each pair of headphones.
The HiFiMan HE560 is 45 ohms.....
So two pairs in parallel will be 22.5 Ohms......
WITH THE JUMPERS IN, the A-100 will easily drive several pairs in parallel, and each will receive the same amount of power as it would if connected individually.
In this configuration, the frequency response will also be identical in both situations.

IF YOU HAVE THE JUMPERS OUT.... then the output is being driven through the 220 Ohm dropping resistors.
In that situation, with two pairs of headphones connected at once, the power reaching each pair FOR A GIVEN VOLUME SETTING will be somewhat less than half of what would reach a single pair.
(Because the load impedance is halved, more power will be stopped by the dropping resistor, so the total reaching both pairs will be less; and that total will then be divided between the two pairs.)
For a given volume setting, each pair will play about 5 dB quieter when connected that way...... or, to look at it differently, if you unplug either pair, the volume of the other will jump up about 5 dB.
This should still be perfectly safe for both pairs of headphones.
In this configuration, you may also notice a slight difference in frequency response depending on whether one or two pairs is connected.
(The exact difference will depend on the specific impedance characteristics of that particular model, but should be relatively minimal....)



TheAnalogman said:


> If I bought a splitter to connect to the headphone jack (so da wife and myself can listen together), would this work? Does anyone know how the output specs would change? Power, impedance etc? With and without the jumpers installed? I'm looking at driving 2 HE560s. Thanks


----------



## HiFiRebel (Nov 7, 2018)

So as of yesterday, I am a proud owner of Emotiva BasX A-100 amp. Just connected it today and all is well in HiFiRebel land. However, I have question.

My sound goes via USB from my PC (Foobar2k playing FLACs) to my DAC (FX-Audio DAC X6) then to A-100 amp and to my headphones (Philips Fidelio X2) (no speakers connected). Question is, does the DAC just acts as a pass-through, or it also have a say in sound quality?

The reason I ask is, I have Argon Mk3 headphones on order and they are meant to be extremely hard to drive. I still have a long wait for them to actually arrive, but I want to squeeze every bit of goodiness out of them when they arrive. Hence the purchase of A-100 and plan to install the jumpers (once I actually get them, Emotiva UK didn't include them in the box).

So the question is, should I upgrade my DAC too since it is not the most high end DAC possible?


----------



## kukkurovaca (Nov 7, 2018)

HiFiRebel said:


> The reason I ask is, I have Argon Mk3 headphones on order and they are meant to be extremely hard to drive. I still have a long wait for them to actually arrive, but I want to squeeze every bit of goodiness out of them when they arrive. Hence the purchase of A-100 and plan to install the jumpers (once I actually get them, Emotiva UK didn't include them in the box).
> 
> So the question is, should I upgrade my DAC too since it is not the most high end DAC possible?



FWIW, you definitely don't need to upgrade the DAC specifically for the sake of the Argons. That's not to say you won't see benefits from upgrading to a nicer DAC, just that those headphones don't particularly require it.

Oh! But does your existing DAC have variable volume on its RCA out? If not, then a DAC that does have variable volume may be beneficial since you're planning on running the A-100 with the jumpers in.


----------



## garbulky (Nov 7, 2018)

HiFiRebel said:


> So as of yesterday, I am a proud owner of Emotiva BasX A-100 amp. Just connected it today and all is well in HiFiRebel land. However, I have question.
> 
> My sound goes via USB from my PC (Foobar2k playing FLACs) to my DAC (FX-Audio DAC X6) then to A-100 amp and to my headphones (Philips Fidelio X2) (no speakers connected). Question is, does the DAC just acts as a pass-through, or it also have a say in sound quality?
> 
> ...


Your DAC will impact audio quality because it is the thing converting digital audio into an analog signal. Your A-100 amplifies the analog signal. It is not a dac.

Make sure that you connect the RCA outputs of your DAC to the A-100.
I would see what you think with your current DAC. You may be fine with what you've got.
If you install the jumpers - your Argon and fidelio are low impedance headphones around 30 ohms. This would allow your A-100 to push humungous levels of power into your headphones of 12000 milliwatts (see direct drive mode). 1 watt is a 1000 milliwatts.

In comparison most headphones do well with between one and 30 milliwatts. So you are going to want to use caution as you could burn out your headphones easily. When using direct drive mode (jumpers engaged) I would reduce the volume upstream using the volume control of your DAC and then increase the volume knob on the A-100 from zero SLOWLY. One advantage of engaging the jumpers is to bypass the resistor. With the resistor bypassed the output impedance drops to very low - something like 0.5 ohms or less - a good thing. In stock mode the resistor is in the circuit so it increases the output impedance to 220 ohms - not as good. So a low impedance headphones will be subject to certain variations of signal because it's lower than the output impedance. 


Power Output (headphone output; normal mode):
8 Ohms: 60 mW / channel
33 Ohms:  200 mW / channel
47 Ohms:  250 mW / channel
150 Ohms: 430 mW / channel
300 Ohms: 440 mW / channel
600 Ohms: 350 mW / channel


Power Output (headphone output; direct drive mode) (JUMPERS ENGAGED MODE)
(requires internal jumper; USE WITH CAUTION):
8 Ohms:  50 watts / channel
33 Ohms:  12 watts / channel
47 Ohms:  8.5 watts / channel
150 Ohms:  2.6 watts / channel
300 Ohms:  1.3 watts / channel
600 Ohms:  0.6 watts / channel


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## HiFiRebel (Nov 7, 2018)

kukkurovaca said:


> FWIW, you definitely don't need to upgrade the DAC specifically for the sake of the Argons. That's not to say you won't see benefits from upgrading to a nicer DAC, just that those headphones don't particularly require it.
> 
> Oh! But does your existing DAC have variable volume on its RCA out? If not, then a DAC that does have variable volume may be beneficial since you're planning on running the A-100 with the jumpers in.



My DAC does not have variable volume on RCA out, just a straight pass through. Volume know does nothing when working with Emotiva. I know it would be beneficial to cut the power to Emotive with the jumpers in, but is this worth spending money on alone?



garbulky said:


> Your DAC will impact audio quality because it is the thing converting digital audio into an analog signal. Your A-100 amplifies the analog signal. It is not a dac.
> 
> Make sure that you connect the RCA outputs of your DAC to the A-100.
> I would see what you think with your current DAC. You may be fine with what you've got.
> ...


I don't plan to drive my Fidelio X2 with the Emotiva once I install the jumpers in. They will be used directly from the DAC since they are so easy to drive. On my DAC quarter of power (volume knob) is already quite loud with X2. For the time being, until I get Argons and install the jumpers, I use Emotiva with X2, but that will change.

If I'm not mistaken Fostex T50RP Mk3, which Argon Mk3 is based on, are around 50 Ohm, plus there might be some changes to the specs after all the mods are done, so I'm not 100% sure what's the true specs of Argons. I've heard that they are extremely hard to drive, hence the Emotiva purchase.

When it comes to DAC, in my head I see DACs as all equal. I mean it's a analogue to digital converter. Can signal be converted in a different way? I understand that a poor quality converter can loose data (quality), but above a certain price point, all DACs should be equal... or am I talking rubbish?

The way I see it is as with HDMI, the signal is either there or not. It doesn't matter if the cable is a £5 cable or £500, they are all the same - it is a digital signal, 1s and 0s. I see DACs in a same way, they either work or they don't. They can't "colour" a sound, like an amp does... right?

In my case the DAC X6 just acts as a pass through, it converts the signal and sends it away to Emotiva. Would a different DAC actually make any difference?


----------



## Yevgen Chupak

I have Argons2 and actually, can't see any reason to set up that jumper. In normal mode they drive my argons just fine. Unless u wanna become deaf pretty soon.


----------



## HiFiRebel

Yevgen Chupak said:


> I have Argons2 and actually, can't see any reason to set up that jumper. In normal mode they drive my argons just fine. Unless u wanna become deaf pretty soon.


The way I understand the reviewers is: yes, you can drive the Argons even directly from your phone and a sound would come out, but to get every last drop out of them, they require a lot of power. Then the sound changes... apparently.


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## kukkurovaca (Nov 7, 2018)

HiFiRebel said:


> My DAC does not have variable volume on RCA out, just a straight pass through. Volume know does nothing when working with Emotiva. I know it would be beneficial to cut the power to Emotive with the jumpers in, but is this worth spending money on alone?



It depends on how much you like/dislike controlling volume from your operating system rather than via a knob, probably. Also another easy option would be to get a "passive preamp" which is basically just a volume knob with an RCA passthrough.



HiFiRebel said:


> When it comes to DAC, in my head I see DACs as all equal. I mean it's a analogue to digital converter. Can signal be converted in a different way? I understand that a poor quality converter can loose data (quality), but above a certain price point, all DACs should be equal... or am I talking rubbish?
> 
> The way I see it is as with HDMI, the signal is either there or not. It doesn't matter if the cable is a £5 cable or £500, they are all the same - it is a digital signal, 1s and 0s. I see DACs in a same way, they either work or they don't. They can't "colour" a sound, like an amp does... right?



Yes and no. The analogy to HDMI isn't quite right, because the DAC is converting sound from digital to analog, it's generating the analog signal that is being passed to your amp. (The analogy to HDMI cables would be expensive USB cables, and yeah, there isn't a strong argument for those.)

But it is true that most DACs are not intended to color sound and generally speaking there should not be big differences between most well-implemented DACs. (There are exceptions; the tube hybrid amp section in my ALO CDM is less colored than its DAC section. But that's not the norm.)

In terms of impedance and output, there should not be any change to the impedance of the Argon vs. stock Fostex T50s, and in fact if you're the non-perforated ZMF pads, the overall sensitivity of the headphones will actually go up, because the pads have a much better seal than a stock T50. (Plus the cup is fully closed.) They're not at all harder to drive than stock T50s. So, even with these headphones, you do not need anywhere _remotely _near the ful power of the A-100 to hit ear-damaging levels of volume.

Edit: _To clarify, you don't want the A-100 to play the Argons any louder than you already can with your existing DAC/amp. The argument from the MOAR POWER folks is that the headphones should sound better at the same volume._


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## garbulky (Nov 7, 2018)

HiFiRebel said:


> My DAC does not have variable volume on RCA out, just a straight pass through. Volume know does nothing when working with Emotiva. I know it would be beneficial to cut the power to Emotive with the jumpers in, but is this worth spending money on alone?


First in stock mode you won't have nay issues.
But with jumpers in, without the variable volume on the DAC, with jumpers in, you will have little play on the volume control. Things might get loud very quickly. At the very lowest end of the volume there is a natural channel imbalance making one side soudn louder than the other side. After that there is no significant imabalance. Depending on the sensitivity of your headphones you may or may not encounter problems having useful volume knob travel. I would at the very least start with the volume knob of the A-100 at ZERO and then slowly increase it. If you don't have issues, then you will be okay. There are things called attenuators that you can stick in there at the RCA ouptut. Schiit has a passive volume control that is $50 which can also reduce the volume from the RCA output. I would personally just try it - VERY carefully - to see if it just works.



> I don't plan to drive my Fidelio X2 with the Emotiva once I install the jumpers in. They will be used directly from the DAC since they are so easy to drive. On my DAC quarter of power (volume knob) is already quite loud with X2. For the time being, until I get Argons and install the jumpers, I use Emotiva with X2, but that will change.
> 
> If I'm not mistaken Fostex T50RP Mk3, which Argon Mk3 is based on, are around 50 Ohm, plus there might be some changes to the specs after all the mods are done, so I'm not 100% sure what's the true specs of Argons. I've heard that they are extremely hard to drive, hence the Emotiva purchase.
> 
> ...


Digital transmission is a 1 or zero. This is digital to digital like in HDMI. So what matters is the timing and also if it is a one or zero. So as long as it's digital, for the most part you are okay. It's a digital to analog converter. I'm of the opinion that yes there is a difference.

But a DAC converts digital to analog. And analog music is NOT a 1 or zero. It's a complex waveform that hits a huge number of different voltages. 
.
For me, different dacs sound different. Most of the dacs I didn't like had problems with treble detail and tone sounding artificial, bright, and lacking in detail. They also had problems with the sensation of a seamless left to right soundstage and a natural sense of dynamics. The same goes for amplifiers. 

However as far as measurements are concerned most decent dacs are able to produce signals that should be inaudible in difference. As long as your below -80db in the noise floor things should be pretty much indistinguishible. Most cheap electronics can acheive this specification. BTW the same goes for amplifiers. And most units are capable of that.

Did you know for speakers most of the time you will only be listening to at 1 watt of power except for loud peaks where you might get 10 watts unless you are playing loud. For headphones you will be listening at about 1-7 milliwatts of power. So very little power. However despite these low power requirements, you'll notice that some amplifiers can sound better than others. The A-100 for instance sounds a heck of a lot better to me than most other headphone amps I've heard though they all have "adequate power".

Why to me the differences are audible in both amps and dacs despite it supposed to be inaudible. I can't explain. But there are a good number of people that hear differences in dacs and a good amount that don't.
So for you, you might be right - there might not be a difference. Me, I think there's a good difference. But it may not be true for you.


----------



## HiFiRebel

kukkurovaca said:


> It depends on how much you like/dislike controlling volume from your operating system rather than via a knob, probably. Also another easy option would be to get a "passive preamp" which is basically just a volume knob with an RCA passthrough.
> 
> 
> 
> ...


Thank you! So if I understand it right, a better DAC could make a difference, but it's not guaranteed. And even if there is a difference, it might be so small that it would be hard to notice. Nobody really knows. So effectively I could just save my money and stay on the same DAC and use it to drive my X2's. 

And no, I don't plan to use full power on Argons after installing jumpers. I know that it would damage them (or my hearing) before I actually get to full power.


----------



## HiFiRebel

garbulky said:


> First in stock mode you won't have nay issues.
> But with jumpers in, without the variable volume on the DAC, with jumpers in, you will have little play on the volume control. Things might get loud very quickly. At the very lowest end of the volume there is a natural channel imbalance making one side soudn louder than the other side. After that there is no significant imabalance. Depending on the sensitivity of your headphones you may or may not encounter problems having useful volume knob travel. I would at the very least start with the volume knob of the A-100 at ZERO and then slowly increase it. If you don't have issues, then you will be okay. There are things called attenuators that you can stick in there at the RCA ouptut. Schiit has a passive volume control that is $50 which can also reduce the volume from the RCA output. I would personally just try it - VERY carefully - to see if it just works.
> 
> 
> ...


Thank you. Please understand that I am not arguing my point here at all. I have way too little knowledge and experience with expensive equipment to be able to argue my point. I am here just to ask questions and to learn. If you say that you can hear a difference between DACs, who am I to say differently. 

I am just trying to understand whether investing in a different DAC would actually make a difference for me, but if I understand it right, nobody knows if I would actually notice a difference. Hence, I think I will just save my money and keep what I have. 

A RCA volume knob is a different story. It would help me with the Emotiva power, however $50 for a knob is a lot of money. Maybe I will be able to find one second hand somewhere.


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## HiFiRebel

It's Shiit SYS, right?

http://www.schiit.com/products/sys


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## kukkurovaca

HiFiRebel said:


> Thank you! So if I understand it right, a better DAC could make a difference, but it's not guaranteed. And even if there is a difference, it might be so small that it would be hard to notice. Nobody really knows. So effectively I could just save my money and stay on the same DAC and use it to drive my X2's.



Exactly, I would say it's a low priority as an upgrade.


----------



## HiFiRebel

kukkurovaca said:


> Exactly, I would say it's a low priority as an upgrade.


Thank you kindly.


----------



## KeithEmo

While the basic operating principle is simple, the circuitry inside a DAC is actually very complex, and there is a lot of variation between them.
(Let me put it this way... the circuitry inside a DAC is a _LOT_ more complex than the circuitry in an amplifier... and so has a lot more opportunity to sound different.)
The short answer is that there are many different ways to convert that signal... and all of them can be done well or badly... with more or less accurate results.

Different DACs use very different circuitry to accomplish the same goal.
As with amplifiers, many audiophiles insist that either all DACs sound exactly the same, or that the differences are trivial...
While others find the differences to be significant.
Likewise, certain DACs allow you to choose between multiple different filter options, each of which sounds somewhat different.
I would suggest that you listen to at least a few different DACs and judge for yourself.

I would also note that, as with amplifiers, price isn't necessarily a significant factor....
(There are some expensive DACs that don't perform well... and some low cost ones that do.)



HiFiRebel said:


> My DAC does not have variable volume on RCA out, just a straight pass through. Volume know does nothing when working with Emotiva. I know it would be beneficial to cut the power to Emotive with the jumpers in, but is this worth spending money on alone?
> 
> 
> I don't plan to drive my Fidelio X2 with the Emotiva once I install the jumpers in. They will be used directly from the DAC since they are so easy to drive. On my DAC quarter of power (volume knob) is already quite loud with X2. For the time being, until I get Argons and install the jumpers, I use Emotiva with X2, but that will change.
> ...


----------



## KeithEmo

Another thought on the range of the Volume control.....

You can increase the useful range of the Volume control on the A-100 by putting a pair of good quality passive attenuators in-line with the input.
By reducing the level of the input signal, they allow you to apply more gain with the Volume control on the A-100 to reach the same level.
Passive attenuators are relatively cheap, won't significantly affect audio quality, and you won't have to worry about channel matching (even cheap attenuators have quite good precision).

You can get a a pair of RCA-unbalanced 12 dB attenuators for about $25.
They'll work best if you plug the attenuators into the A-100, then plug your input interconnects into the attenuators.

Something like this will do the job quite nicely...
https://www.parts-express.com/harrison-labs-12-db-rca-line-level-audio-attenuator-pair--266-244



garbulky said:


> First in stock mode you won't have nay issues.
> But with jumpers in, without the variable volume on the DAC, with jumpers in, you will have little play on the volume control. Things might get loud very quickly. At the very lowest end of the volume there is a natural channel imbalance making one side soudn louder than the other side. After that there is no significant imabalance. Depending on the sensitivity of your headphones you may or may not encounter problems having useful volume knob travel. I would at the very least start with the volume knob of the A-100 at ZERO and then slowly increase it. If you don't have issues, then you will be okay. There are things called attenuators that you can stick in there at the RCA ouptut. Schiit has a passive volume control that is $50 which can also reduce the volume from the RCA output. I would personally just try it - VERY carefully - to see if it just works.
> 
> 
> ...


----------



## garbulky

HiFiRebel said:


> Thank you. Please understand that I am not arguing my point here at all. I have way too little knowledge and experience with expensive equipment to be able to argue my point. I am here just to ask questions and to learn. If you say that you can hear a difference between DACs, who am I to say differently.
> 
> I am just trying to understand whether investing in a different DAC would actually make a difference for me, but if I understand it right, nobody knows if I would actually notice a difference. Hence, I think I will just save my money and keep what I have.
> 
> A RCA volume knob is a different story. It would help me with the Emotiva power, however $50 for a knob is a lot of money. Maybe I will be able to find one second hand somewhere.


No argument at all. What I'm saying is that just because I think there's a difference, I don't have any facts backing me up. Measurements indicate that there shouldn't be a difference. So the measurements are on the side of people that don't hear a difference  So I didn't want to just say yes there's a difference because that may be a tad bit biased on my part  

My gear is an Emotiva DC-1 DAC (which I really like) coupled to the A-100 to a Sennheiser HD600. The DC-1 is also coupled by XLR to a set of Emotiva XPA-1 gen 2 monoblocks. Recently I tried Emotiva's PA-1 monoblocks and I thought they were just fantastic.


----------



## garbulky

HiFiRebel said:


> It's Shiit SYS, right?
> 
> http://www.schiit.com/products/sys


Yes. Or you could get an Emotiva control freak (used) on the Emotiva forums by posting a want to buy ad on the emporium section. Just specify you want the unbalanced. You should be able to get one for about $35-40. I would do that over the in line attenuator which I've tried several. But honestly I would just try the different modes first and just see what you think.


----------



## HiFiRebel

Thank you all. Your help and input is very much appreciated.

I think I will wait to see how my DAC performes and just hunt a cheaper RCA volume knob. I still have at least a couple of months before I get the Argons, so plenty of time to find something here in UK. 

Thank you!


----------



## rockytopwiz

I have a t20rp and it sounds better off the a-100 with jumpers in as opposed to without jumpers in.


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## HiFiRebel

Can someone confirm what the jumpers actually look like (mine weren't included with the amp)? Someone mentioned that they look like jumpers like they used add to hard drives? Emotiva's not replying so I might just order them myself. 

Are these the same?

https://www.ebay.co.uk/itm/25x-2-54...7:g:uwwAAOSw54xUX1Yf:rk:2:pf:1&frcectupt=true


----------



## IBJamon

Pretty much, yes


----------



## HiFiRebel

That Emotiva is too powerful for my Fidelio X2 even without jumpers in lol Just above the imbalance bit on the bottom of the scale is already quite loud with them. I had to dial -5dB in Foobar


----------



## KeithEmo

Yes.... and they're the same as the little black jumpers so commonly used on computer add-in cards to set things.



HiFiRebel said:


> Can someone confirm what the jumpers actually look like (mine weren't included with the amp)? Someone mentioned that they look like jumpers like they used add to hard drives? Emotiva's not replying so I might just order them myself.
> 
> Are these the same?
> 
> https://www.ebay.co.uk/itm/25x-2-54...7:g:uwwAAOSw54xUX1Yf:rk:2:pf:1&frcectupt=true


----------



## HiFiRebel

IBJamon said:


> Pretty much, yes





KeithEmo said:


> Yes.... and they're the same as the little black jumpers so commonly used on computer add-in cards to set things.



Thank you


----------



## HiFiRebel

Daft question time, and I apologise for posting it here, as it is not directly related to A-100.

Which is better for sound quality:
a. keeping the software volume low (Windows or Foobar) and gain more volume control in the amp,
b. keeping the software volume maxed out but have less volume control in the amp (get loud much quicker)?

Which will give me better sound quality? Does it even matter?

I remember back in the days the advice was to keep software volume lower than 100%, around 80% was optimal. Is that the case still?

BTW I got the fuses, cable and jumpers from Emotiva now


----------



## legion1capone

How would this amp play with the ZMF classics (modded T50RP mkIII)?


----------



## garbulky

HiFiRebel said:


> Daft question time, and I apologise for posting it here, as it is not directly related to A-100.
> 
> Which is better for sound quality:
> a. keeping the software volume low (Windows or Foobar) and gain more volume control in the amp,
> ...


Windows you want to keep the volume at 100% because it's a digital volume control that is lossy. You lose audio quality the lower you reduce it. Ideally you want to use the mini-x volume control. But if you want you can use the foobar volume control to reduce the volume just to allow a bit more play in the mini-x volume control. It's not the end of the world if you use the Foobar volume control. Honestly I wouldn't stress too much. But you don't want the software volume controls below 50%.
If you use Foobar you should install the WASAPI plug in to allow bit perfect playback in WASAPI mode.


----------



## HiFiRebel

garbulky said:


> Windows you want to keep the volume at 100% because it's a digital volume control that is lossy. You lose audio quality the lower you reduce it. Ideally you want to use the mini-x volume control. But if you want you can use the foobar volume control to reduce the volume just to allow a bit more play in the mini-x volume control. It's not the end of the world if you use the Foobar volume control. Honestly I wouldn't stress too much. But you don't want the software volume controls below 50%.
> If you use Foobar you should install the WASAPI plug in to allow bit perfect playback in WASAPI mode.


Thank you. Much appreciated. I will be Googling WASAPI mode tonight after work. Thanks!


----------



## HiFiRebel

legion1capone said:


> How would this amp play with the ZMF classics (modded T50RP mkIII)?


I bought this amp to power Argon Mk3 (which is also modded T50RP mk3). However, I don't have the headphones yet (waiting in the queue) so can't comment yet, but it is meant to be a good combo from what I heard.


----------



## Yevgen Chupak

HiFiRebel said:


> I bought this amp to power Argon Mk3 (which is also modded T50RP mk3). However, I don't have the headphones yet (waiting in the queue) so can't comment yet, but it is meant to be a good combo from what I heard.


i have Argon mk2 and never used dial for more than 2oclock in stock mode


----------



## KeithEmo

This is true for any software (digital) volume control.

With digital audio, the best quality is obtained if you use something like WASAPI mode, and leave the DIGITAL Volume set to 100%.
The reason is that all digital volume controls work by "making the numbers smaller" - which absolutely unavoidably reduces the resolution.
Any setting other than 100% means that your signal is no longer "bit perfect" - because the bits have to be changed to make the number smaller.
In reality, this isn't a big deal, and may not be all that noticeable with minor changes, but the audio will get grainy sounding if you use the digital volume control to turn it down a lot.

The Volume control on the A-100 is a real analog potentiometer.
That means that it will not add any significant noise or distortion, and it will not reduce the resolution of the signal.
(However, at very low settings, you may run into channel mismatch, and you won't have much range to turn the knob physically.)

Some DACs actually have an analog ladder network volume control (it's an analog stepped volume control in a chip).
Those also will NOT reduce the resolution.
So, if you have one of those, simply use it.

However, if you're DAC doesn't have a good Volume control, your best option would be to put a pair of FIXED ANALOG ATTENUATORS between the output of your DAC and the input of the A-100.
These reduce the level by a fixed amount, don't introduce significant noise or distortion, don't cost much, and have really good channel matching.
So, for example, if you put a pair of 12 dB attenuators between the DAC and the A-100, you will be able to turn the volume knob on the A-100 12 dB higher, for the same setting on the computer, and nothing much else will change.
(You can get a pair of these for about $25..... )

Something like these will do the job nicely:
https://www.parts-express.com/harrison-labs-12-db-rca-line-level-audio-attenuator-pair--266-244



garbulky said:


> Windows you want to keep the volume at 100% because it's a digital volume control that is lossy. You lose audio quality the lower you reduce it. Ideally you want to use the mini-x volume control. But if you want you can use the foobar volume control to reduce the volume just to allow a bit more play in the mini-x volume control. It's not the end of the world if you use the Foobar volume control. Honestly I wouldn't stress too much. But you don't want the software volume controls below 50%.
> If you use Foobar you should install the WASAPI plug in to allow bit perfect playback in WASAPI mode.


----------



## HiFiRebel

WASAPI installed and configured in Foobar, all the software volumes set to 100%, volume knob indicator added. Thanks guys.

Jumpers still not installed, waiting until I get my Argon Mk3. Question, after installing jumpers is there any sound quality change, or just the power changes?


----------



## garbulky

HiFiRebel said:


> WASAPI installed and configured in Foobar, all the software volumes set to 100%, volume knob indicator added. Thanks guys.
> 
> Jumpers still not installed, waiting until I get my Argon Mk3. Question, after installing jumpers is there any sound quality change, or just the power changes?


For me there is for the positive. But I think it depends on the headphones. Your headphones have lower impedance than mine. Your negative may be that you encounter more hiss than you like. But for the positive you may encounter better dynamics and more speed. For me, in stock mode it sounded good, got very loud, but I did hear some mild compression on dynamics. Don't get me wrong the thing sounded great.It was very quiet.  

 With the jumpers engaged, the sound felt faster. That "smear" wasn't there. I got a bit of hiss on silence but not overly so. 
BTW Emotiva is introducing a class A balanced headphone amp. But no idea when it is coming out. It will probably be a good amount of time.


----------



## rockytopwiz

garbulky said:


> For me there is for the positive. But I think it depends on the headphones. Your headphones have lower impedance than mine. Your negative may be that you encounter more hiss than you like. But for the positive you may encounter better dynamics and more speed. For me, in stock mode it sounded good, got very loud, but I did hear some mild compression on dynamics. Don't get me wrong the thing sounded great.It was very quiet.
> 
> With the jumpers engaged, the sound felt faster. That "smear" wasn't there. I got a bit of hiss on silence but not overly so.
> BTW Emotiva is introducing a class A balanced headphone amp. But no idea when it is coming out. It will probably be a good amount of time.


Yeah, I agree with all of this.  Def depends on the headphones.  With jumpers sounds best with hard to drive planars.  Our emotiva representative did just give us an option to get more play with the volume pot tho, so it may sound better with lower impedence hps with those attenuators installed.


----------



## HiFiRebel

My Fidelio X2 are very easy to drive, I'll wait for the Argons as planned. Thanks again.


----------



## garbulky

Just an update, I'm trying out a pair of sennheiser HD6xx and I can confirm that they sound good with the jumpers put in (direct drive). Keep in mind that I am using the A-100 as a power amp and my Emotiva DC-1 DAC controls the volume to allow me a greater range of volume. I've also tried the HD600.


----------



## rockytopwiz

This is one piece of gear I don't see going anywhere, such a crazy value.  

Here's to hoping Emo stays in the value realm for future HP products.  Prices are getting a little crazy out here.


----------



## Mightygrey

Hey guys,

I'm loving the A100 w/ jumpers installed on my HD580/650's, but find I'm getting a noticeable noise-floor on my 300-ohm ZMF Eikons. 

I'm wondering what the addition of the IE-Match from IFI in the audio chain might do in terms of impedance, noise, and matching? The specs say that it has:

Input Impedance: > 16 Ohm

Output Impedance: < 2.5 Ohms (High-Sensitivity) < 1 Ohms (Ultra-Sensitivity)


----------



## IBJamon

Mightygrey said:


> Hey guys,
> 
> I'm loving the A100 w/ jumpers installed on my HD580/650's, but find I'm getting a noticeable noise-floor on my 300-ohm ZMF Eikons.
> 
> ...



I'm pretty sure those things do the same thing my adapters do that I created a few pages back.

Based on my experiences, creating a voltage divider adapter on the output might even be better than lowering the volume on the input.  You still can get most of the power, and at lower volume levels, the noise is basically silent, and the output impedance is still really low (<3 Ohms).  I love it!

https://www.head-fi.org/threads/emotiva-a-100.825970/page-15#post-14057326

In my opinion, this is the best of all worlds for high efficiency headphones.


----------



## Mightygrey

IBJamon said:


> I'm pretty sure those things do the same thing my adapters do that I created a few pages back.
> 
> Based on my experiences, creating a voltage divider adapter on the output might even be better than lowering the volume on the input.  You still can get most of the power, and at lower volume levels, the noise is basically silent, and the output impedance is still really low (<3 Ohms).  I love it!
> 
> ...


Great success.


----------



## KeithEmo

Interesting....

To be honest, I took a quick look, but I can't seem to tell for sure exactly what sort of circuitry it contains.
From the descriptions, I'm guessing it's a low-impedance resistor-based attenuator.
If so, then it might in fact help to lower the noise floor, and so might work well.

I would, however, note two things:

1) 
The output impedance will still be higher with the IE-Match than without it.
The output impedance of the A-100, with the jumpers installed, is actually well below one ohm.
I can't imagine this being a problem - or mattering at all with most headphones.
However, it might sound a tiny bit different.

2)
Compared to most headphone amplifiers, with the jumpers in, the A-100 potentially delivers a _LOT_ of power.
The IE-Match seems designed to be used with low-powered devices, and doesn't have a power rating.
So, if you were to turn the A-100 way up, especially with no headphones connected, you might burn up the IE-Match.
(So I would be careful NOT to do that by mistake.)
(I'm pretty sure you wouldn't hurt the A-100.)



Mightygrey said:


> Hey guys,
> 
> I'm loving the A100 w/ jumpers installed on my HD580/650's, but find I'm getting a noticeable noise-floor on my 300-ohm ZMF Eikons.
> 
> ...


----------



## Mightygrey

KeithEmo said:


> Interesting....
> 
> To be honest, I took a quick look, but I can't seem to tell for sure exactly what sort of circuitry it contains.
> From the descriptions, I'm guessing it's a low-impedance resistor-based attenuator.
> ...



Thanks @KeithEmo - the added output-Z doesn't really seem to affect the frequency-response on my Eikons so far, they do seem to play nicely with high output-Z devices (like OTL Tube amps). 

I'll play carefully with the volume-pot too!


----------



## pngpng

@IBJamon @KeithEmo  I love what the a-100 is doing for my Argons (T50RP), but I'd like to get rid of the noise floor. I've tried 10db attenuators going into the amp but it hasn't solved the problem. Any recommendations on what resistor values I should use to make an L-pad on the amp's output? 
I'm hoping to get rid of the noise floor without increasing impedance too much.


----------



## garbulky

pngpng said:


> @IBJamon @KeithEmo  I love what the a-100 is doing for my Argons (T50RP), but I'd like to get rid of the noise floor. I've tried 10db attenuators going into the amp but it hasn't solved the problem. Any recommendations on what resistor values I should use to make an L-pad on the amp's output?
> I'm hoping to get rid of the noise floor without increasing impedance too much.


I think you may need to look towards a different amp or use the stock config with the resistor. The A-100 is a very good amp, however with certain headphones without the resistors there will be too much noise floor.  Emotiva has an upcoming class A Headphone amp that is also balanced. It has less power than the A-100 but is still supposed to provide a good amount of power. Its release date is unknown. It's called the HP-1 and should be about the size of the Emotiva DC-1.


----------



## HiFiRebel

pngpng said:


> @IBJamon @KeithEmo  I love what the a-100 is doing for my Argons (T50RP), but I'd like to get rid of the noise floor. I've tried 10db attenuators going into the amp but it hasn't solved the problem. Any recommendations on what resistor values I should use to make an L-pad on the amp's output?
> I'm hoping to get rid of the noise floor without increasing impedance too much.


That is quite worrying to read as I am waiting for my Argons to be made and also bought the A-100 specifically to power these headphones. Please do post here if you manage to solve the issue.


----------



## rockytopwiz

pngpng said:


> @IBJamon @KeithEmo  I love what the a-100 is doing for my Argons (T50RP), but I'd like to get rid of the noise floor. I've tried 10db attenuators going into the amp but it hasn't solved the problem. Any recommendations on what resistor values I should use to make an L-pad on the amp's output?
> I'm hoping to get rid of the noise floor without increasing impedance too much.


What source are you using?


----------



## IBJamon

pngpng said:


> @IBJamon @KeithEmo  I love what the a-100 is doing for my Argons (T50RP), but I'd like to get rid of the noise floor. I've tried 10db attenuators going into the amp but it hasn't solved the problem. Any recommendations on what resistor values I should use to make an L-pad on the amp's output?
> I'm hoping to get rid of the noise floor without increasing impedance too much.



It's possible your A-100 is noisier than some, or something upstream isn't quite right.  My T50RP mk3s do not have noticeable noise in pass-through mode.  It's my other headphones that need the adapters.  For me, anyway.


----------



## rockytopwiz (Dec 1, 2018)

IBJamon said:


> It's possible your A-100 is noisier than some, or something upstream isn't quite right.  My T50RP mk3s do not have noticeable noise in pass-through mode.  It's my other headphones that need the adapters.  For me, anyway.


Samesies

This seems to be the biggest complaint about this amp and I believe it is due to user error.  The jumpers only need to be applied for really hard to drive cans, when they are used with less hard to drive headphones the noisefloor is no longer black but this is because you are sending them way more power than they need.  You are hooking your headphones up to a speaker amp, which is what is needed for hard to drive planars like the t50s or he-6.  This amp has more than enough power for any headphone, giving this kind of power is even too much for the hard to drive cans and you do not get much play with the volume knob.  Either way tho hooking up easy to drive cans to a-100 w jumpers is too much power and there will be a audible noise floor.  Take the jumpers back out if you don't have hard to drive cans.


----------



## tim0chan

rockytopwiz said:


> Samesies
> 
> This seems to be the biggest complaint about this amp and I believe it is due to user error.  The jumpers only need to be applied for really hard to drive cans, when they are used with less hard to drive headphones the noisefloor is no longer black but this is because you are sending them way more power than they need.  You are hooking your headphones up to a speaker amp, which is what is needed for hard to drive planars like the t50s or he-6.  This amp has more than enough power for any headphone, giving this kind of power is even too much for the hard to drive cans and you do not get much play with the volume knob.  Either way tho hooking up easy to drive cans to a-100 w jumpers is too much power and there will be a audible noise floor.  Take the jumpers back out if you don't have hard to drive cans.


the argons are modded t50s so they fit the criterion tho


----------



## rockytopwiz

tim0chan said:


> the argons are modded t50s so they fit the criterion tho



That's why I ask what source he is using.  I notice the noise floor with my other headphones, but not with my t20.


----------



## pngpng

I actually hear the noise floor even without any inputs going into the amp. So I think it's something with my particular unit unfortunately. It's a used a-100 (first gen) that I modified for a front panel 1/4 inch trs like in the original post. I'm not running any resistors though. I think I'll try putting together an adapter to run the headphones from the rear outputs and seeing if that fixes it. I read somewhere in this thread that grounding the chassis might help too.


----------



## tim0chan

pngpng said:


> I actually hear the noise floor even without any inputs going into the amp. So I think it's something with my particular unit unfortunately. It's a used a-100 (first gen) that I modified for a front panel 1/4 inch trs like in the original post. I'm not running any resistors though. I think I'll try putting together an adapter to run the headphones from the rear outputs and seeing if that fixes it. I read somewhere in this thread that grounding the chassis might help too.


it is possiible that thee newer gen has tighter qc thus lower noise floor? i also intend to get this for an argon so this is concerning


----------



## garbulky

rockytopwiz said:


> Samesies
> 
> This seems to be the biggest complaint about this amp and I believe it is due to user error.  The jumpers only need to be applied for really hard to drive cans, when they are used with less hard to drive headphones the noisefloor is no longer black but this is because you are sending them way more power than they need.  You are hooking your headphones up to a speaker amp, which is what is needed for hard to drive planars like the t50s or he-6.  This amp has more than enough power for any headphone, giving this kind of power is even too much for the hard to drive cans and you do not get much play with the volume knob.  Either way tho hooking up easy to drive cans to a-100 w jumpers is too much power and there will be a audible noise floor.  Take the jumpers back out if you don't have hard to drive cans.


I thought the amp powered my HD600's to unbearable volumes either way. However when you take the jumpers out you lower the output impedance from 220 ohms to something close to 1 ohm. Which makes a difference at all volume levels for my headphones imo.


----------



## ckhirnigs113 (May 24, 2020)

I have just purchased an A100 used. I plan on getting some Argon MK3 planars in the near future to go with it. I’ve read conflicting opinions in this thread about whether it’s worth it to put the jumpers in when using relatively easy to drive phones like my HD58X. My main concern is impedance mismatch when leaving the jumpers out. I don’t have the A100 yet, but I’m going to try both options and see which sounds best.

If the amp sounds better with the jumpers in I’ll either need to buy a passive preamp like the JDS Labs OL Switcher or Schitt SYS or the in-line attenuators described earlier in the thread so I’ll have some use of the volume knob with my 150 ohm HD58X. If anyone has opinions on the better option, I’d appreciate the info.


----------



## bequietjk

I got on the drop for the 58x and grabbed an A100 as well, ck.  Let me tell you that even without jumpers in there is plenty of power for the 150ohm cans.  But my concern is the white noise that i hear.  With no jumpers, no rca attached and headphones plugged in, its pitch black until i turn the amp on and within a few seconds there is just this slightest white noise I can hear.  This noise gets a bit dimmer when i pair my t50rp up with it.  With jumpers installed, the 58x noise floor is well above that and too much for me to sit through.  Again, its less with t50rp.

Ive considered getting an ifi iematch after everything ive been reading because after all this amp is simply amazing in value, power and aesthetics.  Hopefully the little ifi will remedy my issue, I don't know to be honest.

Ck, what will the jds labs I'm switcher do, or the schiit sys?  I've also thought about picking up another amp to run to the line out on the a100 hoping to remedy the noise.


----------



## ckhirnigs113

bequietjk said:


> Ck, what will the jds labs I'm switcher do, or the schiit sys?  I've also thought about picking up another amp to run to the line out on the a100 hoping to remedy the noise.


The hope is by adding a passive pre-amp in front of the A100 I could lower the gain from my DAC and therefore have a lot more useable travel on the A100 volume pot. I assume you have very little room on the volume knob with you're 58X, right? I haven't received my A100 yet, but I'm not encouraged by your experience with the same exact setup. The fact that you have the T50RP (are they unmodded?) and still get the hiss/white noise is not good news either. 

I'm definitely aware of the iFi iEMatch, and I'd be very interested in its effect on the A100. I think it may get rid of the hiss, but the question is whether it will negatively impact the sound with its resistors. Maybe someone has used this product with the A100 and can report their results to us.


----------



## ckhirnigs113

Looks like @Mightygrey had "great success" with the iEMatch and I also found another success story on reddit here: https://www.reddit.com/r/headphones...d_a_good_use_for_the_ifi_iematch_controlling/

Might have to bite the bullet and pick up an iEMatch. If I find one used, it should be cheaper than the passive pre-amps I was considering and likely more effective at reducing the hiss.


----------



## Yevgen Chupak

I have Argons MK|| and can't hear ANY hiss or noise NoJumperMode... Also even without jumpers argons sounds ok.


----------



## bequietjk

I just want to note that the t50rp non jumped is close to no noise and would be tolerable for the casual listener.  But we all know with those cans we need more power and installed jumpers deliver, but with a noticeable increase in noise.  Ive never used 300 or 600ohm phones but I would imagine the noise to be very close to inaudible?  Considering how much less noise there is with t50rp compared to the 58x.  

Ill be ordering the IEmatch and make sure to report back asap!  

Also, is it possible to use the a100 as a preamp?  Say, if i wanted to go PC>DAC>A100>Atomamp, in hopes of remedying some white noise.


----------



## ckhirnigs113

I don’t think the A100 functions as a preamp because you don’t have volume control on the output. It’s more of a pass through. I don’t think it will solve any of the hiss issues because the signal will pass through untouched to whatever other amp you connect in line.


----------



## HiFiRebel

I bought the A-100 brand new a month or so ago. Its sole purpose is to drive Argon Mk3 when I get them. Currently, until I get my Argons, I use it with my Philips Fidelio X2 which are extremely easy to drive. I use them with jumpers out, aka stock. I get absolutely no noise. Not even a hint of a hiss. However, I will be interested to read how you get on with the IEmatch and the noise issue. I will report my findings once I get my Argons (still a few weeks away).


----------



## kukkurovaca

The Argons and other T50 headphones are _not_ notably hiss sensitive. They're the only headphones that I can use with the Little Dot B4, which is far and away my hissiest amp. (Terrible noise floor issues.) Sennheiser HD800 are very similarly hard to drive (but with different power requirements, of course, higher impedance and higher sensitivity) but definitely pick up hiss more readily. 

I don't have an A-100 so far (just b/c I don't have room for a desktop setup), but it's weird that some folks find significant noise floor issues with Fostex RP driver headphones and some don't. I know issues with source have been suggested and in some cases eliminated. Have folks also looked into the possibiliity that the issue is coming from noisy mains power? Maybe power conditioning/etc. of some sort would help? 

Also, FWIW, to those who are concerned about using an impedance adapter between the amp and your headphone, don't worry about an increase in output imepdance affecting the Argon. Planars are not very sensitive to output impedance differences. This means that you should be able to find cheaper solutions than the iFi IEMatch, which is complicated and expensive in part b/c it's to provide impedance matching for very low-impedance multi-driver IEMs with balanced cabling. Whereas Penon sells simple impedance-adding adapters for $8, for example. I don't know for sure that it would work as well, but it might be worth a try before paying IEMatch money.


----------



## ckhirnigs113

I'm going to inquire with iFi and see what they think about using the iEMatch in this extreme situation with such a powerful amp and full-size cans. They are usually very good at responding in their product threads.


----------



## kukkurovaca

ckhirnigs113 said:


> I'm going to inquire with iFi and see what they think about using the iEMatch in this extreme situation with such a powerful amp and full-size cans. They are usually very good at responding in their product threads.



You may want to ask them whether their Earbuddy (which is less quite a bit less expensive) will work as well or better. It should; you certainly don't need balanced cabling or sub-1ohm output impedance.


----------



## bequietjk

Rebel, the sound that I'm hearing w/o jumpers isn't exactly a hiss.  It's more like the sound of a light bulb being on.  

My testing was with the A100 and a home stereo setup and with both the t50rp and 58x.  

Cans into Home stereo:
Monster HKS 3500 MKII powercenter, 2 THX preamps then finally going into a Denon AVR4802.  With everything on and keeping my headphones on my head, then plugging into the headphone out of the AVR, there is zero distinguishable sound difference. It's pitch black.  All music sounds like it's coming from absolute darkness.

Cans into A100:
I went as far as to plug the emo into the monster powercenter just to assure clean power.  Same routine.  The room is also very, very quiet but there is a slight ambient static.

This type of noise gets drowned out when audio is coming through for the most part but, after all it is there and becomes part of the sound you are hearing.  

Yessss, the IEmatch is a pricey figure.  I would love to pickup something cheaper, but hopefully it works.


----------



## ckhirnigs113

I posted in the iEMatch thread and asked for iFi's opinion. I also asked if the cheaper Ear Buddy would suffice for this situation. I'll relay what they say once I get a response.


----------



## rockytopwiz

bequietjk said:


> Rebel, the sound that I'm hearing w/o jumpers isn't exactly a hiss.  It's more like the sound of a light bulb being on.
> 
> My testing was with the A100 and a home stereo setup and with both the t50rp and 58x.
> 
> ...


Have you tried going from your receiver to the a-100?


----------



## bequietjk

rockytopwiz said:


> Have you tried going from your receiver to the a-100?


I don't suspect it's an input source issue.  Unless you mean plugging the power cable into the AVR?  I don't think the AVR has power outlets in it.


----------



## rockytopwiz

bequietjk said:


> I don't suspect it's an input source issue.  Unless you mean plugging the power cable into the AVR?  I don't think the AVR has power outlets in it.


If you don't have some form of dac ahead of the amp it's very likely to have an increased noise floor.  You didn't mention what input source you were running to the basx is why I asked.


----------



## pngpng

bequietjk said:


> Cans into A100:
> I went as far as to plug the emo into the monster powercenter just to assure clean power.  Same routine.  The room is also very, very quiet but there is a slight ambient static.
> 
> This type of noise gets drowned out when audio is coming through for the most part but, after all it is there and becomes part of the sound you are hearing.



That's how I would describe my experience as well. It's not noticeable if there's music playing but you can hear it when there are quieter passages. I've ordered some resistors to make an L-pad attenuator for the output. I'll give an update when I get around installing them. The Argons really do benefit from the extra power. Notable improvement with imaging over my JDS o2, at the expense of a bit of detail.


----------



## bequietjk

Sorry rocky, the line goes like this.

Pc > OL Dac > BasX > 58x/T50RP

Btw i just want to mention how happy i am with the ol dac + a100.  Almost went with the el dac but OL was more budget fri3ndly.


----------



## garbulky

bequietjk said:


> I just want to note that the t50rp non jumped is close to no noise and would be tolerable for the casual listener.  But we all know with those cans we need more power and installed jumpers deliver, but with a noticeable increase in noise.  Ive never used 300 or 600ohm phones but I would imagine the noise to be very close to inaudible?  Considering how much less noise there is with t50rp compared to the 58x.
> 
> Ill be ordering the IEmatch and make sure to report back asap!
> 
> Also, is it possible to use the a100 as a preamp?  Say, if i wanted to go PC>DAC>A100>Atomamp, in hopes of remedying some white noise.


Doesn't work as a passthrough preamp.


----------



## ckhirnigs113 (Dec 3, 2018)

garbulky said:


> Doesn't work as a passthrough preamp.


I thought that’s exactly how it works. It’s not a preamp but only a pass through. This means you can pass the signal from your DAC through the A100 to another amp, like the Atom in @bequietjk ’s example.

Here’s the quote from Emotiva’s product page:

A loop output provides a duplicate of the input signal to facilitate chaining additional amplifiers or other device
It won’t solve the white noise issue except by avoiding the amplification of the A100 altogether. It should be the same exact thing as connecting the DAC directly to the Atom instead of the A100.


----------



## bequietjk

ckhirnigs113 said:


> I thought that’s exactly how it works. It’s not a preamp but only a pass through. This means you can pass the signal from your DAC through the A100 to another amp, like the Atom in @bequietjk ’s example.
> 
> Here’s the quote from Emotiva’s product page:
> 
> ...



Ok thats what i was trying to figure out.  Bummer!  Would be nice if that were a feature, and hopefully an addition to this HP-1 rumored to be on its way ;D


----------



## rsvette12 (Dec 3, 2018)

LasherV said:


> I just received my A-100 today and man am I pleased  I had one problem though. I missed my Darkvoice 336se Tube sound that I have become addicted to. I decided to try something a little different. I used my Darkvoice as a Pre-Amp to my A-100, it does have pre-outs after all. All I can say is OMG what an amazing upgrade! I have kept all my Tube Warmth, Wide Soundstage, and overall Smoothness that I love soooo much about Tubes, but the Bass has at least tripled on my M1060's. This A-100 has so much dynamic range and punch that the only word that comes to mind is Effortless. If there are any Darkvoice owners out there that are thinking of getting this A-100 as a solid state for your Planars give this a try. I could not be more pleased with what this has done for my listening pleasure. Well guess I'm back to re-rolling all my tubes again to see how they sound with this set up lol.
> 
> Lasher




Hi Guys:

New here and just picked up a Emotiva 100 for my HD650's - Pretty impressive - I use it for my guitar interface and interested in this post about adding a tube preamp - would it be worth trying this, I do not want to mess up Emotiva or mess with Emotivas functionality as it is - if preamp makes it even better then that would be great

I am thinking of getting a Little Dot MKII - would like the III but invested enough all ready

If you feel this might be a nice edition - how would I run this configuration - right now I have guitar interface into the input of Emotiva and plug in headphones into front of Emotiva

What would be the routing if I added tube preamp ?

Also recommendations on no jumper or add jumper on HD650's why I ask is the bass is not quite there starts to break up a bit

Thanks much


----------



## Yevgen Chupak

Only way i can hear that hiss in NoJumper mode is to wear 600ohm 102-126dbs sensitivity Beyerdynamic T1p... And it's audible only around 70% volume. So as for me, there is a possibility that your unit is noisier than mine.


----------



## rsvette12

Thanks I have no hiss - also put jumpers in i think it sounds tighter that way - my main question is adding a tube pre-amp - would it be worth it - would it make a difference ? thanks much


----------



## garbulky (Dec 4, 2018)

ckhirnigs113 said:


> I thought that’s exactly how it works. It’s not a preamp but only a pass through. This means you can pass the signal from your DAC through the A100 to another amp, like the Atom in @bequietjk ’s example.
> 
> Here’s the quote from Emotiva’s product page:
> 
> ...


Yes - works as a passthrough but not as a passthrough preamp. However the knob does work as a preamp  (but doesn't add gain - only reduces) but not when passing through the signal.


----------



## ckhirnigs113 (May 24, 2020)

garbulky said:


> Yes - works as a passthrough but not as a passthrough preamp. However the knob does work as a preamp  (but doesn't add gain - only reduces) but not when passing through the signal.


I'm a little confused by what you're saying. Are you saying the gain from the source can be lowered like in a passive preamp when connected to the output of the A100. You say "not when passing through the signal", so how does the knob act as a preamp for lowering gain if you can't pass through the signal.

For example, if I connect my OL DAC to the A100 input and then connect my iFi iCan SE to the output of the A100, are you saying I can use the volume knob to lower the gain going to my iFi amp instead of sending an identical signal to what is being received from the OL DAC (aka unity gain)? I'm having to ask these questions because I won't receive my A100 until Thursday to test what you're saying. Maybe I'm just misunderstanding what you're trying to describe.


----------



## KeithEmo

I didn't seem to get the whole quote here.....

The _ORIGINAL_ "Mini-X" models.... 
Those are the ones that didn't include a headphone jack on the front......
And which some folks modified to add that jack themselves......
Were not as quiet as the newer BasX A-100 (which has the headphone jack and the jumper option).

Note that the original version did include...
- a Gen1 model, with silver trim and a silver knob
- a Gen2 model, with black trim and knob



tim0chan said:


> it is possiible that thee newer gen has tighter qc thus lower noise floor? i also intend to get this for an argon so this is concerning


----------



## KeithEmo

There are a whole bunch of factors involved in designing an optimum attenuator.
The output impedance of the A-100, with the jumpers in, is extremely low.... probably lower that you need.
And, yes, any attenuator on the output is going to raise the output impedance a bit.
And the "optimum" values will depend on the headphones.

The output impedance of an L-pad in this case is basically the impedance of the two resistors in PARALLEL.
(So, if you use a 47 Ohm and a 4.7 Ohm, the output impedance will be about 4 Ohms.)
The output impedance of the A-100 itself is a small fraction of an Ohm.
For best damping you want the output impedance to be about 1/5 to 1/10 or less that of your phones.

The other concern is power.
At full power the A-100 delivers 50 watts into 8 Ohms.
50 watts will incinerate a 1/10 watt resistor in a matter of seconds.
(Or take the skin off your fingertips if you touch it accidentally.)
And, at 50 watts, even a real 50 watt power resistor may get _VERY_ hot over time.

(The A-100 would cheerfully run an L-pad with an 8 Ohm and a 1 Ohm resistor... 
But it might get quite hot, depending on the headphones you have, and how efficient they are. )

If you want to use "fixed values", I think I'd go with:
- 47 Ohms on top (get a nice 3w or 5w one there)
- 4.7 Ohms on the bottom (1/2 watt or 1 watt is just fine there)
Remember that you need two of each for stereo.

Depending on what's readily available, you could just as well go with 33 Ohms and/or 3.3 Ohms.
With most headphones, those wattage ratings are extremely conservative, so they won't get terribly warm.
You don't really need super-quality resistors... but old style wire wound power ones have a lot of inductance.
(Which may alter the frequency response in interesting ways.)

If you wanted to make a cool little box with some flexibility you could include several different values.
If I were doing it, I would probably add two switches.
One switch would optionally parallel a second 47 Ohm with each of the originals (= 23.5 Ohms).
The other would optionally parallel a second 4.7 Ohm with each of those (= 2.3 Ohms).

This would give you four options:
- 47 Ohms + 4.7 Ohms
- 47 Ohms + 2.3 Ohms
- 23.5 Ohms + 4.7 Ohms 
- 23.5 Ohms + 2.3 Ohms

Note that, as an example, the first and fourth ones on that list will give you close to the same attenuation.
(The fourth will give you slightly higher damping than the first one - and get four times as warm.).
And different combinations will sound slightly different with different headphones... 

It's also worth noting that you can tweak the frequency response of your headphones by paralleling small capacitors, or capacitors in series with resistors, with one or the other of the resistors in the voltage divider. We call that passive equalization. Paralleling capacitance with the resistor to ground will introduce a high frequency roll off; paralleling a small capacitor with the top resistor will introduce a rising high frequency response, adding a resistor in series with either capacitor will cause the effect to shelve (level off) at some frequency. The calculations are much too complicated to go into here and the values depend on the resistors you've chosen and the impedance of your headphones. If you do try that, be sure to use good quality non-polar capacitors, preferably film types of some sort, rated for at least 50V or 100V, and avoid electrolytics if at all possible.

(You should avoid paralleling capacitors with both resistors of each pair at the same time, especially if they don't also include series resistors, because it will put an odd load on the amplifier, and could cause problems.)

This is the sort of thing that's fun to experiment with...
You can produce some interesting and dramatic changes (for better or worse)...
And it doesn't cost much to experiment...

If this sort of thing interests anyone....
PM me and I can go into it in more detail (to a point).  
(It may take me a while to reply.)



pngpng said:


> @IBJamon @KeithEmo  I love what the a-100 is doing for my Argons (T50RP), but I'd like to get rid of the noise floor. I've tried 10db attenuators going into the amp but it hasn't solved the problem. Any recommendations on what resistor values I should use to make an L-pad on the amp's output?
> I'm hoping to get rid of the noise floor without increasing impedance too much.


----------



## KeithEmo

The Loop Output is simply a passthrough (on the current A-100 it really is just wired directly to the input).
This means that an exact copy of the input comes out of the Loop Output.
It will _NOT_ be affected by the Volume control on the A-100.



ckhirnigs113 said:


> I'm a little confused by what you're saying. Are you saying the gain from the source can be lowered like in a passive preamp when connected to the output of the A-100. You say "not when passing through the signal", so how does the knob act as a preamp for lowering gain if you can't pass through the signal.
> 
> For example, if I connect my OL DAC to the A-100 input and then connect my iFi iCan SE to the output of the A-100, are you saying I can use the volume knob to lower the gain going to my iFi amp instead of sending an identical signal to what is being received from the OL DAC (aka unity gain)? I'm having to ask these questions because I won't receive my A-100 until Thursday to test what you're saying. Maybe I'm just misunderstanding what you're trying to describe.


----------



## ckhirnigs113

KeithEmo said:


> The Loop Output is simply a passthrough (on the current A-100 it really is just wired directly to the input).
> This means that an exact copy of the input comes out of the Loop Output.
> It will _NOT_ be affected by the Volume control on the A-100.


That's what I thought. Does the loop output work while the unit is turned off or only while powered on? If the loop output works with the unit turned on, will it work while headphones are connected enabling two amps to use the same source simultaneously?


----------



## bequietjk

For the pre-built attenuators I have seen this when I had my Polaris.  It's Garage1217's own attenuator
http://www.garage1217.com/garage1217_diy_tube_headphone_amplifiers_012.htm

Whether or not it will be applicable in reference to what Keith is talking about will be subjective.  I know for sure though I am going to pickup that, the earbuddy or iematch.


----------



## garbulky

ckhirnigs113 said:


> I'm a little confused by what you're saying. Are you saying the gain from the source can be lowered like in a passive preamp when connected to the output of the A-100. You say "not when passing through the signal", so how does the knob act as a preamp for lowering gain if you can't pass through the signal.
> 
> For example, if I connect my OL DAC to the A-100 input and then connect my iFi iCan SE to the output of the A-100, are you saying I can use the volume knob to lower the gain going to my iFi amp instead of sending an identical signal to what is being received from the OL DAC (aka unity gain)? I'm having to ask these questions because I won't receive my A-100 until Thursday to test what you're saying. Maybe I'm just misunderstanding what you're trying to describe.


You can adjust the volume on the headphone jack or speaker posts using the front knob but not the
Volume on the rca output jack. The rca out is a pass through only. Hope that makes sense


----------



## ckhirnigs113

Does anyone have experience using the Garage1217 attenuator with the A-100 that @bequietjk posted the link for? It looks to be better built than either iFi option and about the same price as the iEMatch.


----------



## KeithEmo

The Loop Output should work whether the unit is On or Off.
It is literally connected directly to the Input by a piece of wire (or a circuit trace).
It is NOT disabled when you plug a pair of headphones into the Output.



ckhirnigs113 said:


> That's what I thought. Does the loop output work while the unit is turned off or only while powered on? If the loop output works with the unit turned on, will it work while headphones are connected enabling two amps to use the same source simultaneously?


----------



## bequietjk

Nice Keith!  So basically if you have say an o2 to the output, you would power your power hungry cans through the a100 while simultaneously powering your grados through the o2.


----------



## ckhirnigs113

KeithEmo said:


> The Loop Output should work whether the unit is On or Off.
> It is literally connected directly to the Input by a piece of wire (or a circuit trace).
> It is NOT disabled when you plug a pair of headphones into the Output.


Very cool. That will make it very easy to compare amps using the same DAC or use two amps for different types of cans like @bequietjk suggested.


----------



## ckhirnigs113 (Dec 4, 2018)

For those interested, here is iFi’s response on using the A-100 with jumpers installed with their iEMatch. Note when they say “install jumpers” they effectively mean “remove jumpers”.


iFi audio said:


> The correct solution for the Emotiva Amp is to re-install the jumpers responsible for attenuation of the headphone outputs.
> 
> The iEMatch is designed to withstand normal use with headphone amplifiers and very low impedance headphones, it has power limits and is not suited for the use at very high power levels. The same story goes for EarBuddy.


Looks like the iFi products aren’t the best-suited products for removing hiss on the A-100.  I’m going to inquire with the folks at Garage1217 about their -20dB attenuator and see if it’s up to the task.


----------



## rsvette12

No takers on my questions  thanks


Hi Guys:

New here and just picked up a Emotiva 100 for my HD650's - Pretty impressive - I use it for my guitar interface and interested in this post about adding a tube preamp - would it be worth trying this, I do not want to mess up Emotiva or mess with Emotivas functionality as it is - if preamp makes it even better then that would be great

I am thinking of getting a Little Dot MKII - would like the III but invested enough all ready

If you feel this might be a nice edition - how would I run this configuration - right now I have guitar interface into the input of Emotiva and plug in headphones into front of Emotiva

What would be the routing if I added tube preamp ?

Also recommendations on no jumper or add jumper on HD650's why I ask is the bass is not quite there starts to break up a bit

Thanks much


----------



## pngpng

KeithEmo said:


> There are a whole bunch of factors involved in designing an optimum attenuator.
> The output impedance of the A-100, with the jumpers in, is extremely low.... probably lower that you need.
> And, yes, any attenuator on the output is going to raise the output impedance a bit.
> And the "optimum" values will depend on the headphones.
> ...



Wow, thank you Keith! Amazing response and the bit about eq'ing the frequency response using caps is really cool. I use equalizerAPO but it's very interesting to hear how it can be done in analog. I'll send you a pm for further details. =)


----------



## rsvette12

I use equalizerAPO also with Peace addon - great programs


----------



## bequietjk

@rsvette12 

Put the jumpers on!  And report your experience back to us!


----------



## rsvette12

They were not on to begin with - put them on last night - pretty simple took about 2 minutes 

Sound is better just wondering if bass would be fuller (more warmth maybe) with tube pre-amp or would it not be much different, at the moment its better with jumpers but bass can get a little muddy still - thanks Bequiet


----------



## rockytopwiz

Them good ole Tennessee boys, emotiva is seriously the best.


----------



## rsvette12

rockytopwiz said:


> Them good ole Tennessee boys, emotiva is seriously the best.



? Me not even close - Snowville Mass here


----------



## rockytopwiz

rsvette12 said:


> No takers on my questions  thanks
> 
> 
> Hi Guys:
> ...


Not speaking from personal experience but there is a video by Paul at psaudio on YouTube saying the best place to add a tube is in the preamp. 

To do it you would go out of the dac(guitar interface)- into preamp line in-line out of the preamp into line in on the amp.  

I've never done this and there are varying opinions on if it's worth doing.


----------



## rsvette12

Thanks for the info much appreciated - so the Tue would before the Emotiva thats interesting thought it would be the other way around - searching found nothing on this subject  

That post by Lasher caught my attention and I would not give up my Emotiva but those tube amps are pretty cool looking and if there was some benefit to it I would give it a go


----------



## rsvette12

Just found this - very interesting may be something I might wan to try as I am using with my guitar - and looks like it may be a great match ohms wise with Emotiva - Paul videos are very interesting - thanks

https://wccftech.com/review/little-dot-mk-ii-review-miracle-tube-amp/


----------



## ckhirnigs113

Thanks to some very helpful correspondence with John Seaber at JDS Labs, I have finally come to understand that a preamp will not solve the hiss issue with the A100. A preamp can lessen the noise of a source. A preamp cannot do anything about the noise floor of an amp. 

Since iFi said the iEMatch is not a good option for this purpose, I’m hoping the Garage1217 -20dB attenuator will be up to the task of handling the power of the A100. I sent them an email asking just that, so I’ll let you all know what they say.


----------



## bequietjk

ckhirnigs113 said:


> Thanks to some very helpful correspondence with John Seaber at JDS Labs, I have finally come to understand that a preamp will not solve the hiss issue with the A100. A preamp can lessen the noise of a source. A preamp cannot do anything about the noise floor of an amp.
> 
> Since iFi said the iEMatch is not a good option for this purpose, I’m hoping the Garage1217 -20dB attenuator will be up to the task of handling the power of the A100. I sent them an email asking just that, so I’ll let you all know what they say.



yessss.  totally waiting on them to email you back.  that cable looks promising.


----------



## ckhirnigs113

I sure am delving deep considering I don’t even receive my A100 until Thursday. Maybe I’ll be one of the lucky ones that doesn’t have any audible hiss. I’ll still need either an attenuator or preamp if I want a decent amount of useable range on the volume knob with the jumpers installed using my HD58X. 

Fingers crossed for the Garage1217 little cable!


----------



## pngpng (Dec 6, 2018)

I'm happy to report that installing the L-pad attenuator did the trick! I'm very happy with how it's worked out. The noise floor is much improved and I'm getting more range with the volume knob to boot.
Didn't affect the sound quality at all to my ears. Same A100 goodness but without the slight hiss which is a huge win for me. I ended up using some MASSIVE wirewound resistors which will hopefully dissipate the heat better. I suppose someone could make an external box as well. There's still a hiss when the volume knob is very high, but in my case it's in a range that would literally blow my ears out.

As KeithEmo mentioned previously(link), the precise resistor values will depend on your headphone impedance, but he gives some general resistance values. I went with 7.5 ohm / 0.5 ohm resistors to keep the impedance down which is NOT advised since the resistors will get really hot. My resistors are installed inside the amp so I'm not too concerned. Still waiting for Keith's opinion on it though.

Edit: KeithEmo's response to my question:


> The thing you need to remember with a voltage divider is that the power consumed by the voltage divider is largely independent of the power that's reaching your headphones.
> And, with the values you used, _MOST_ of the power will end up as heat in the resistors.
> So, from the point of view of heat, you have an 8 Ohm load connected to an amplifier.
> At full power, the A-100 can deliver about 50 watts into 8 Ohms...
> ...


----------



## KeithEmo

You're quite right...

As with most small audio amplifiers with an analog potentiometer Volume control....
Inside each channel of the A-100 is an audio amplifier with a fixed amount of gain.
The amplifier itself has a fixed noise floor.
The input signal passes through the Volume control, which is a voltage divider, and to the amplifier.

If the source is noisy, that noise will be reduced when you turn down the Volume control.
However, the noise floor of the amplifier itself remains the same.
Under most situations, you don't notice the noise from either source.
However, if you do notice noise, which one is more noticeable simply depends on which is louder.

--------------

When you use attenuators for line-level signals, for example between a preamp and an amp, the amount of actual power involved is tiny, and can usually be ignored. In that situation 1/2 watt, or even 1/10 watt, resistors will generally be just fine, and that's what you'll often see inside line level attenuators.

Even the headphone amplifiers in most AVRs and smart phones really only put out at most a fraction of a watt.
So, an attenuator that you plan to attach to something like that doesn't see much power.

To put things in perspective:
If you were to connect a 60 Hz test tone to the input of the A-100...
And crank it up to its maximum undistorted output...
With the jumpers on...
Each channel could cheerfully deliver 50 watts into an 8 Ohm resistor.
After all, the A-100 is rated to deliver 50 watts per channel into 8 Ohms.
However, 50 watts is also the rated power of a typical bench-top soldering iron.
(So, if it all gets turned into heat, 50 watts is quite a bit of heat.)

At those same settings, if you substituted 32 Ohm resistors, each would only be getting 12 watts.
(This is why you really need to understand the math involved.)

I don't want to scare anyone...
And, in real life, with music, the situation won't be anywhere near that extreme...
But you can see how an attenuator, designed to handle a small fraction of a watt, might have problems.
So, if you don't know what's inside the little box, it is a good idea to find out for sure.
(Just tell the manufacturer that you want to connect it to the _OUTPUT_ of a 50 watt amplifier...)



ckhirnigs113 said:


> Thanks to some very helpful correspondence with John Seaber at JDS Labs, I have finally come to understand that a preamp will not solve the hiss issue with the A100. A preamp can lessen the noise of a source. A preamp cannot do anything about the noise floor of an amp.
> 
> Since iFi said the iEMatch is not a good option for this purpose, I’m hoping the Garage1217 -20dB attenuator will be up to the task of handling the power of the A100. I sent them an email asking just that, so I’ll let you all know what they say.


----------



## bequietjk (Dec 6, 2018)

Just a heads up, I couldn't wait long enough @ckhirnigs113 for G1217 to get back to you, so I emailed them as well.

Jeremy got back to me and mentioned that it would be risky considering the subjective uses and variables involved with using their attenuator and the A100.  However!  He did mention that with enough interest, he could run a group buy for a special amp attenuator module. The amp module would be around 4x4 in shape and cost around $75.  A month's build time.

What to do, what to do!?


----------



## ckhirnigs113 (Dec 7, 2018)

bequietjk said:


> Just a heads up, I couldn't wait long enough @ckhirnigs113 for G1217 to get back to you, so I emailed them as well.
> 
> Jeremy got back to me and mentioned that it would be risky considering the subjective uses and variables involved with using their attenuator and the A100.  However!  He did mention that with enough interest, he could run a group buy for a special amp attenuator module. The amp module would be around 4x4 in shape and cost around $75.  A month's build time.
> 
> What to do, what to do!?


I actually got a response from Jeremy at Garage1217 too, but his initial optimism that their adapter would work changed to hesitation after he double checked with one of his co-workers.

I almost quoted his email saying it’d be ok to use, but when I asked him if he was ok with me quoting him here he decided to delve a little deeper and changed his mind.  I think the massive amount of power the A100 puts out could very easily damage the adapter they sell. Then again, this amp could easily damage most headphones too if you’re not careful with the volume knob.

Weather delays have prevented my A100 from being delivered, so I still haven’t gotten any firsthand experience with the amp yet. If it doesn’t have a ton of hiss when I plug my HD58X in, I’m thinking I may try those Harrison Labs 12dB attenuators first for $25 to have more play on the volume knob.

I am interested in the little device Jeremy at Garage1217 has in mind. I assume it would plug into the headphone out on the A100. What would the output impedance be? If he could remove the audible noise floor of the amp and keep the output impedance low, it may be the best option for a lot of us here. If the output impedance isn’t kept low, we might as well just take the jumpers out and use the resistors already in place in the A100. Pending the details on this little adaptor, I do like the idea of a group buy.

@bequietjk See if you can get some specifics from Jeremy and report back.


----------



## vormhat

I have the a100 and hd58x and don't hear any hiss. I don't even with my 80 ohm Beyers. It's when I go to portable optimized cans that I hear hiss like 32 ohm.


----------



## ckhirnigs113

vormhat said:


> I have the a100 and hd58x and don't hear any hiss. I don't even with my 80 ohm Beyers. It's when I go to portable optimized cans that I hear hiss like 32 ohm.


Do you have the jumpers installed?


----------



## ckhirnigs113 (Dec 7, 2018)

@bequietjk I actually got a detailed email from Jeremy from Garage1217 about his idea for the custom power adapter box too. Somehow I managed to overlook it in my inbox.

Sounds like he’s thinking about a box with speaker cable terminals and a 6.3mm input and output. He thinks it will be about 4”x4” in size. He said output impedance should be about 3.5ohm, so all in all it sounds pretty perfect for our needs.

I’m on the fence about whether or not the speaker cable terminals are necessary. Those with the older A100 model already have adapters to connect straight to the terminals on the amp, so I think maybe we could keep the device smaller and perhaps cheaper to produce by not including the speaker terminals inputs. I’d like to get others opinions on this though.

I told Jeremy I’d try to gauge the level of interest in a custom product like this. I also invited him to join our discussion in this thread to answer technical questions. If he doesn’t join us here, I can relay questions to him.


----------



## IBJamon

I used 2w resistors for my L-pads (they are NOT wirewound, as I didn't want additional inductance) and they have been working perfectly.  I do not crank it up too much, of course, because I value my ears.  They were barely small enough to pack them into my 1/4" cable adapter plug.  It was not easy.... and I don't look forward to ever having to do it again.  A small project box would be much easier.


----------



## rockytopwiz

Cr


----------



## ckhirnigs113

IBJamon said:


> I used 2w resistors for my L-pads (they are NOT wirewound, as I didn't want additional inductance) and they have been working perfectly.


Are these resistors you used rated at 2w continuous or peak. The attenuator Garage1217 currently sells is rated at 1w continuous and 4w peak. I’m just wondering if your resistor is rated lower or higher than theirs. They don’t think their current attenuator is rated high enough to use with the A100 with jumpers installed. This is why they are looking into making a custom power adapter box for our specific needs with this amp.


----------



## vormhat

Yup, forgot to mention that. I'm running full power.


----------



## ckhirnigs113 (May 24, 2020)

Finally got my A100 today. The guy I bought it from had already installed the jumpers and warned me to be careful with the volume knob.

First thing I did was check the noise floor of the amp with my relatively easy to drive HD58X. It’s definitely audible but not terrible like I had feared. Then I plugged the amp into my source, the JDS Labs OL DAC, and checked for any noise from the source. Nothing additional to my ears. The only thing I heard was the amp itself, and it didn’t get louder when turning up the volume.

Before playing any music through the amp I made sure the knob was all the way at the minimum position. Unsurprisingly, I found I had very little useable range on the knob. I could maybe get to 8-8:30 before things got louder than I like. I did at least manage to get past the point where channel imbalance is an issue on the volume pot. That’s good news for me. And to be honest, I didn’t notice the hiss/noise floor while music was playing. I’m a little bit OCD about stuff like this, so I might still end up with an attenuator box/cable to get rid of the hiss and get more use of thre volume knob.

I haven’t taken the jumpers out yet to see how the thing sounds with the resistors in place. I’ll do that later tonight and report back. I need to do some comparisons with my iFi iCan SE using the loop output on the A100. I don’t have the means to precisely volume match, but I’ll do my best to get things pretty close.

Now that I’ve used the A100 directly with my HD58X with jumpers installed, I really don’t see any reason why I couldn’t use the current attenuator that Garage1217 sells. As long as I’m careful with the volume knob (and it is truly ridiculous that there is no position indicator on it) I think that item would be perfectly fine. I understand them being hesitant to clear it as compatible with an amp with this kind of power, but for any volume I’ll be listening at, I can’t imagine there’s any danger.


----------



## HiFiRebel

@ckhirnigs113 
time to add the volume know indicator yourself then


----------



## bequietjk

Nice, ck!  Good to hear that finally came in.  It's a beast ain't it?

I just wanted to make clear of the issues that I had.

w/58x
Jumpers installed:  audible hiss, not very much volume flexibility.  It gets loud very quickly.
Jumpers uninstalled:  only a static ambience of the amp itself.  this I'm very ocd about.

I'm reluctant to say that I ended up taking mine to ups today for a refund, but I wanted to mention that it wasn't an easy decision.  The value for such a power house and amp with flexibility does not go unmentioned.  Initially I bought it for the headphone output and passive speaker ability for future use but I currently run powered speakers anyway, and my ocd kicks in knowing that there is some sort of static amp noise in comparison to the AVR headphone output on the home theater system.  For most this almost inaudible sound is far from a deal breaker and is tolerable.  I'm just being me and am picky.  

Though, you can be sure that as soon as Emo releases that dedicated headphone amp, the rumored "HP-1", I'm going to jump on it asap.  Like, ninja-star fast.


----------



## ckhirnigs113

@bequietjk It’s ironic you let yours go right as mine arrives, haha. I am holding on to mine until I at least get to try it with a pair of planars. I really want the Modhouse Argon or maybe the Hifiman HE-500/560. This amp is meant for that type of headphones. The fact that it sounds so good with my HD58X is just a bonus. 

I did take the cover off the amp and removed the jumpers to see what difference it made in the hiss and sound quality. It certainly removed any audible hiss with my 58X, but the high output impedance was immediately noticeable in much more bloated, wooly bass. It only took me a minute to decide to put the jumpers back in for good. I’ll tackle the hiss with a attenuator eventually. 

I have tried to compare to my iFi iCan SE and can’t tell a huge difference. The iCan SE is no slouch in power, so the major difference on my 58X is the lack of hiss and tons more control with the volume knob (the iCan has 3 gain settings and I use the lowest gain for all my headphones). There may be a bit more weight in the bass with the A100, but without volume matching and testing things blind there is no way to know if it’s all in my head.


----------



## vormhat

I'm contemplating selling the a100 for a JDS Atom. It has 250mw into 300 ohms. Not as powerful of course but probably the most powerful small desktop amp for $99 easily. Anyone else consider this?


----------



## ckhirnigs113

vormhat said:


> I'm contemplating selling the a100 for a JDS Atom. It has 250mw into 300 ohms. Not as powerful of course but probably the most powerful small desktop amp for $99 easily. Anyone else consider this?


@bequietjk did exactly this. He hasn’t received the Atom yet, but I’ve already asked him to report back once he gets his hands on it.


----------



## vormhat

Cool. Reason is that I do own some low impedence cans and the noise floor is too high with the jumpers in. I guess the attenuator would help here as well though the Atom measures very well.

 With the jumpers off and the resistors in use, I'm not crazy about the output impedence and it's influence on frequency response on some headphones.


----------



## bequietjk

Yep.  Biting my nails till it comes in.


----------



## vormhat

I actually came across this article https://diyaudioheaven.wordpress.com/tutorials/power-impedance-etc/ which came with this handy PDF chart with tons of headphones listed:
http://www.mediafire.com/view/dzwe1g73q6pbhnx/headphone power table.pdf

For me, it looks the JDS Atom should power nearly anything except for some really oddballs out there like the AKG K172.  Now, I'm really considering it.


----------



## KeithEmo

The thing you need to remember first is that the power your resistors will see depends on the value of the resistors themselves.
Therefore, the power ratings by themselves are meaningless unless you also know the values of the resistors.
(And the calculations are very different for an L-pad than for a series resistor.)

Here are the "numbers" for the A-100.
At its rated power, when turned up until it clips, the A-100 will deliver 25 VRMS (that is the same no matter what for any load above 6 Ohms or so.).

JUMPERS OUT

When you have the jumpers out, the headphone output is passing through a 220 Ohm series resistor.
So, no matter what load you connect, the output impedance will never be below that, and the output power will be limited accordingly.

So, for example, if you connect 32 Ohm headphones, the total load would be 32 + 220 = 252 Ohms.
That load is going to determine the total power the A-100 is going to be putting out.
And the amount of that power the headphones themselves will see will be 32/252 of that total (most of the power will be consumed by the series resistor).
The source impedance will be 220 Ohms, and the damping factor will be low (32/220; I'm too lazy to calculate it exactly).

If, instead, you connect 300 Ohm headphones.... the total will be 300 + 220 = 520 Ohms.
As you can tell, the overall power will be much less, but a much higher _percentage_ of the power will be going to the headphones.
The source impedance will still be 220 Ohms, but the damping factor will now be around  (300/220)

JUMPERS IN

With the jumpers in you are connected directly to the amplifier's output.
The output impedance of the amplifier by itself is a very small fraction of one Ohm (something like 1/100 Ohm - depending on how tight the connections are).
The damping factor is _VERY_ high (somewhere between several hundred and several thousand).
The maximum output is 25 VRMS.
(Remember that 25 VRMS is a lot of power into 32 Ohms.... but not that much into 300 Ohms.)

ATTENUATORS

Now you have to look at the math involved in output attenuators (JUMPERS IN).
Let's say you want to cut the level down by 16:1.
(I'm going to approximate the numbers, and ignore the headphone's contribution, but we'll be within 10% with 300 Ohm cans, and a little bit further away with lower ones.)

You could make an L-pad with a 7.5 Ohm resistor and a 0.5 Ohm resistor.
With those values, the output impedance will be about 0.4 Ohms, which is really low.
The damping factor with 32 Ohm headphones will be around 70 (high).
BUT, at maximum output, the A-100 could deliver as much as 50 WATTS RMS to the L-pad (most of that will end up heating the 7.5 Ohm resistor).
At 50 watts, a 1 watt resistor will make an impressive flame, and even a 50 watt resistor will get very hot (think ventilation or a heat sink).

If you were to double those values - to 15 Ohms and 1 Ohm....
The output impedance would now be about 0.8 Ohms, which is still very low.
WIth 32 Ohm headphones the damping factor will still be respectable (around 35).
However, the power consumed will be halved, so now our maximum total is about 25 WATTS (the A-100 is running into a 16 Ohm load instead of an 8 Ohm load).

And, if we double them again, - to 30 Ohms and 2 Ohms....
The output impedance will now be about 1.6 Ohms.
But our L-pad will only be burning a maximum of 12 watts.

IT IS IMPORTANT TO NOTE A FEW THINGS.....

1)
Those are maximum numbers.
If your headphones are relatively sensitive, you may not end up turning the A-100 up nearly all the way, so you may be using FAR less power. 
The thing to remember is that the A-100 is CAPABLE of huge amounts of power.

So, for example, if you have efficient 32 Ohm headphones, they may sound great with an L-pad of 7.5 Ohms and 0.5 Ohms.
And, because they're efficient, you may be fine with resistors rated only a few watts.
But, if you EVER try to turn the volume up, but forget to plug in your phones, the first sound you hear will be your resistors catching fire.

2)
Lower output impedance affects different headphones very differently.
It may mean tighter bass, but it may also mean less bass, and again that will depend a lot on the headphones.
Many headphones sound better with more damping, but not all, and some may not sound much different at all.
(Also note that, with the jumpers out, the impedance of the series resistors will react with the impedance of your headphones in more interesting and complex ways).

3)
Most modern small headphone amplifiers you find in equipment have....
- relatively low (but not super low) output impedance (usually from about 0.5 Ohms to 5 or 10 Ohms)
- relatively low power (usually a fraction of a watt)

4)
Higher powered resistors cost slightly more, take up more space, and need to be mounted so they can dissipate heat.
Therefore, any device that costs very little, and is mounted in a tiny plastic box, is NOT going to include high-power resistors.
(It's either going to operate at relatively high impedance, only be good for very small amounts of power, or both.)

5)
It's also worth noting that, when talking about power resistors, many are expected to get quite hot.
A 50 watt power resistor, being fed 50 watts continuous, will get plenty hot to burn fingers and melt plastic.
Power resistors EXPECT to be mounted where they don't touch anything that can melt or burn.
And, even beyond that, many expect to be mounted to a heat sink, or at least in a box with some ventilation.

Since we're playing music, rather than delivering continuous power, they'll run much cooler than their maximum - but they may still get quite hot....
You may be used to "little headphone amplifiers" being so low in power output that "you don't have to worry about heat".... 
And many of those little adapter gadgets are designed with that idea....
That is NOT true here.



ckhirnigs113 said:


> Are these resistors you used rated at 2w continuous or peak. The attenuator Garage1217 currently sells is rated at 1w continuous and 4w peak. I’m just wondering if your resistor is rated lower or higher than theirs. They don’t think their current attenuator is rated high enough to use with the A100 with jumpers installed. This is why they are looking into making a custom power adapter box for our specific needs with this amp.


----------



## KeithEmo

With the jumpers in, the headphone output on the A-100 is connected directly to the same place as the speaker terminals.
(The speaker outputs have slightly lower impedance because they use fatter wires.... but that is not going to matter with headphones.)



ckhirnigs113 said:


> @bequietjk I actually got a detailed email from Jeremy from Garage1217 about his idea for the custom power adapter box too. Somehow I managed to overlook it in my inbox.
> 
> Sounds like he’s thinking about a box with speaker cable terminals and a 6.3mm input and output. He thinks it will be about 4”x4” in size. He said output impedance should be about 3.5ohm, so all in all it sounds pretty perfect for our needs.
> 
> ...


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## ckhirnigs113 (Dec 10, 2018)

KeithEmo said:


> With the jumpers in, the headphone output on the A-100 is connected directly to the same place as the speaker terminals.
> (The speaker outputs have slightly lower impedance because they use fatter wires.... but that is not going to matter with headphones.)


Thanks @KeithEmo. that was my understanding as well. I think what Jeremy (at Garage1217) was thinking was that it may be helpful to have speaker terminal inputs on the power adapter box (aka attenuator) so those with a speaker amp and no headphone out (like on the original A-100) could connect more efficient phones to their amp.

I personally think the speaker terminals are unnecessary for most here because we either have the BasX A-100 that already has a headphone out or we have the original A-100 and have already acquired an adapter to connect directly to the speaker terminals. I think all we need is some robust resistors in a box that allows adequate cooling (as @KeithEmo thoroughly described in his previous post) and keeps the output impedance relatively low. The question becomes: what is the most universally applicable resistor combination that will benefit the most diverse collection of headphones.

All I want to accomplish in my particular situation is to remove the background hiss with my HD58X (150ohm, 104 dB at 1V, 1 kHz) and get a little more useable range on the volume knob. Not sure if inline attenuators like those Harrison Labs -12dB ones you linked to earlier will be necessary as well as an output side attenuator. I would hope the output side attenuator will be enough, but we'll see. The little Garage1217 unit is still in the design phase at the moment.

Is anyone else interested in one of these? I'm not sure how many units are needed to make it a viable build for Jeremy.


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## KeithEmo

Here would be my suggestions......

First off, if you're using the output attenuator, then you _probably_ don't need the input attenuator.
(Unless your source itself has a very high fixed noise floor.)

The values that would make sense are probably going to depend on the headphones themselves.
You also need to remember that damping factor is a ratio between the impedances of the source and load.
(If you're looking for a certain damping factor, the lower the impedance of your headphones, the lower the output impedance you'll need to drive them with.)
I would assume (this is something of a guess) that relatively low impedance headphones are going to act more like loudspeakers.
And so they would see a larger improvement with better damping.

Here are the values I might consider as a starting point.....

For low impedance phones I would go with 7.5 Ohms and 0.5 Ohms.
That will give you a nice low drive impedance with plenty of damping.
The size of the resistors you need will depend on the efficiency of your phones.
More efficient phones mean you'll be running the volume lower so you can get by with smaller resistors.
(And, if your phones are very efficient, you might end up adding those input attenuators after all.)

Doubling those resistor values (15 Ohm and 1 Ohm) will give you the same attenuation with a slightly lower damping factor.
That should also be plenty for most low impedance phones, and you'll be able to get by with smaller resistors.

Your HD58x phones are both high impedance and high efficiency.
I suspect you could get by with much higher values....
Perhaps 47 Ohms on the top resistor.... and 4.7 Ohms, or even 2.2 Ohms, on the bottom one.
That will give you a 2 Ohm output impedance (which will still provide a damping factor of around 75 with your 150 Ohm phones.)
And you will probably be able to use much smaller resistors. 

Remember that, when you're discussing this with someone who manufactures a product, they're going to want to make a product that works well with the widest variety of headphones and amps.
So, connecting to the speaker terminals makes sense, because very few amps are going to give you a high-power output from their headphone jack (the A-100 is the only one I know off hand).

For a product, I might also consider adding a few resistors and switches.
Make the top resistor 33 Ohms.... and add a switch that lets you parallel a second 33 Ohm resistor (for a choice of 33 Ohms or about 16 Ohms).
Make the bottom resistor a 3.3 Ohm one.... and add a switch that lets you parallel a 1.2 Ohm one (for a choice of 3.3 Ohms or about 0.8 Ohms.).
Now, by changing switch settings, you're going to be able to achieve several different attenuation and impedance settings... 
This should give you a better chance of finding one that works well with many different headphones.
(As a commercial product, the box and construction are going to cost more than the parts inside, and this would offer good performance with a much wider variety of headphones. Feel free to pass this on if you like.)



ckhirnigs113 said:


> Thanks @KeithEmo. that was my understanding as well. I think what Jeremy (at Garage1217) was thinking was that it may be helpful to have speaker terminal inputs on the power adapter box (aka attenuator) so those with a speaker amp and no headphone out (like on the original A-100) could connect more efficient phones to their amp.
> 
> I personally think the speaker terminals are unnecessary for most here because we either have the BasX A-100 that already has a headphone out or we have the original A-100 and have already acquired an adapter to connect directly to the speaker terminals. I think all we need is some robust resistors in a box that allows adequate cooling (as @KeithEmo thoroughly described in his previous post) and keeps the output impedance relatively low. The question becomes: what is the most universally applicable resistor combination that will benefit the most diverse collection of headphones.
> 
> ...


----------



## KeithEmo

I should also point out another interesting option.

You (or Jeremy) could design a nice little "semi DIY" unit.
It could be a nice little box, with the proper connectors on the outside, and a small PCB with spring clips inside.
Each user could then select the perfect combination of resistors for the particular headphones they want to use it with.

If I was doing it, as a company, I would ask the user what headphones they have, and provide the unit with the appropriate set of resistors.
Alternately, if spring clips were used, the user could experiment with different values.



ckhirnigs113 said:


> Thanks @KeithEmo. that was my understanding as well. I think what Jeremy (at Garage1217) was thinking was that it may be helpful to have speaker terminal inputs on the power adapter box (aka attenuator) so those with a speaker amp and no headphone out (like on the original A-100) could connect more efficient phones to their amp.
> 
> I personally think the speaker terminals are unnecessary for most here because we either have the BasX A-100 that already has a headphone out or we have the original A-100 and have already acquired an adapter to connect directly to the speaker terminals. I think all we need is some robust resistors in a box that allows adequate cooling (as @KeithEmo thoroughly described in his previous post) and keeps the output impedance relatively low. The question becomes: what is the most universally applicable resistor combination that will benefit the most diverse collection of headphones.
> 
> ...


----------



## ckhirnigs113

KeithEmo said:


> I should also point out another interesting option.
> 
> You (or Jeremy) could design a nice little "semi DIY" unit.
> It could be a nice little box, with the proper connectors on the outside, and a small PCB with spring clips inside.
> ...


Come on Keith, I know you can get this little niche product produced at Emotiva. Then we can have a complete Emotiva solution!


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## bequietjk

The complete Emotiva solution is the release of the HP-1 >


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## ckhirnigs113

bequietjk said:


> The complete Emotiva solution is the release of the HP-1 >


Very true, but I’m hoping to stop buying amps! Easier said than done when I spend so much time on these forums. 

“Welcome to Head-fi, sorry about your wallet.” That’s so true. I’ve been here since 2005! My wallet is most definitely lighter because of this place.


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## ckhirnigs113 (Dec 11, 2018)

@KeithEmo Jeremy from Garage1217 got back with me and basically said you and he are of one mind about offering options on the attenuation based on the headphones being used. He plans to offer two settings on the attenuator box, one with -20dB and one with -10db. Here are his own words describing his design:

“The size resistors needed for this are very large and require custom cooling. I could use cheapy 5-10% tolerance ceramics with heatsink on them but will use much better, high power SMD resistors with a custom cooling implementation. Enough to handle 100W of dynamic power from an amplifier. A little overkill for most situations. The unit will have a -10 and -20dB setting select-able via a switch. Have other values in stock will not be a problem.
Tailoring resistor sets to each headphone, I cannot see real value in it to be honest since the actual output is variable from the amplifier. A couple of set values will more than do the trick. The goal is to attenuate the signal to the point you have a usable volume range from the amplifier and also make it safe for the headphones in use.”

To me it sounds like an iEMatch with the capability of handling the power output of a 100w/channel speaker amp. Should be perfect for the A-100 assuming he is able to keep the output impedance low, which I believe he will. Before discussing the switch on the unit he was aiming for just under 3.5ohm output impedance. I’ve asked him what the -10dB and -20dB switches’ respective output impedances will be. I’ll report back when he responds.

This thing sounds like it will be great for all of us that want to safely use the A-100 or any other moderately-powered speaker amp with more efficient headphones that don’t soak up power like planars.


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## vormhat

The Garage guys have any idea what this would cost? I'd love to keep my a100 and have the ability to drive more efficient cans without the high output impedence we have today. I'd prefer to keep this a100 over getting a JDS Atom.


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## ckhirnigs113

vormhat said:


> The Garage guys have any idea what this would cost?


Jeremy's initial estimate was about $75 for the adapter. He's out of town this week, but he's going to get back to me once he's got more concrete details.


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## HiFiRebel

ckhirnigs113 said:


> Jeremy's initial estimate was about $75 for the adapter. He's out of town this week, but he's going to get back to me once he's got more concrete details.


 Would Shiit SYS not do the same thing for less money?


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## ckhirnigs113 (Dec 13, 2018)

HiFiRebel said:


> Would Shiit SYS not do the same thing for less money?


I thought the same thing until it was explained to me that all a passive preamp like the SYS would do is give more useable range on the A-100 volume knob. Inline attenuators on the RCA inputs of the amp, like these that @KeithEmo suggested, would effectively do the same thing except at a fixed value like -12dB.

Neither solution does anything about the noise floor of the A-100 itself. I hear the hiss even with no source plugged in. This hiss/noise floor doesn’t noticeably increase when turning up the volume on the amp. The only way to get rid of a noise like this is to put something on the headphone output of the amp.

The resistors Emotiva have in place when the jumpers are removed effectively remove the hiss but also drastically increase the output impedance to 220ohm. This may work with some headphones, but with my HD58X for example, the bass loses a lot of control and sounds bloated and a lot muddier.

The solution is to have resistors in place that remove the audible noise floor and give more useable range on the A-100 volume knob while still keeping output impedance relatively low, thus keeping a high damping factor for our headphones. Things like the iFi iEMatch and Garage1217’s own attenuator cable seem like the perfect products in theory for this issue, but unfortunately, they aren't suitable.

The stumbling block is these products were not designed to handle the huge amounts of wattage put out by a speaker amp like the A-100. iFi and Garage1217 both confirmed they don’t recommend using their products with speaker amps. This is why I’m talking to Jeremy at Garage1217 about this custom solution for people like us that want to use our A-100 with jumpers installed with headphones other than just our power-hungry planars (Hifiman, Fostex etc.).


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## HiFiRebel

ckhirnigs113 said:


> I thought the same thing until it was explained to me that all a passive preamp like the SYS would do is give more useable range on the A-100 volume knob. Inline attenuators on the RCA inputs of the amp, like these that @KeithEmo suggested, would effectively do the same thing except at a fixed value like -12dB.
> 
> Neither solution does anything about the noise floor of the A-100 itself. I hear the hiss even with no source plugged in. This hiss/noise floor doesn’t noticeably increase when turning up the volume on the amp. The only way to get rid of a noise like this is to put something on the headphone output of the amp.
> 
> ...


Thank you for detailed explanation. 

I don't experience any noise from my A-100. However, I have not installed the jumpers yet. At the moment I only use Philips Fidelio X2 headphones connected to A-100. They are very easy to drive and even with jumpers out, I am at the low end of volume knob scale and have very little play in the knob between when the initial volume imbalance ends and where it gets very loud. I therefore can't install the jumpers until I get my Argons, because it would limit the volume knob even further to the point where I won't have any play in it at all. 

That's the reason why I have also not invested in Shiit SYS yet (this was top of my list), because I simply don't yet know what I need. When I get Argons and install jumpers and hear a lot of noise, then I would need to find something to solve the issue, but if I don't, I only need some kind of volume pre-amp for when I want to use my X2's with A-100 to increase the volume knob range. At the moment with the X2's, at 9 o'clock it is already quite loud. 10 o'clock is where it is already very loud for my ears, and that is with the jumpers out. I don't have any noise floor at all, dead quiet.


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## ckhirnigs113 (Dec 13, 2018)

@HiFiRebel I also didn’t have any hiss with my HD58X when I took the jumpers out. I just find the sound better with jumpers installed even with these sensitive cans. The hiss is not even noticeable when music starts playing.

To be honest, I didn’t find I had much more play on the volume knob when I took the jumpers out. This surprised me. I assumed I’d be able to get to 11-12:00 but probably didn’t get past 8:30-9:00. With the jumpers installed, I can get past the point of channel imbalance with my HD58X, but it obviously gets really loud really fast with a small turn on the knob.

One thing I don’t know, and maybe @KeithEmo could educate us, is how much attenuation is possible with a passive preamp like the Schiit SYS or JDS Labs OL Switcher versus the fixed -12dB inline attenuators from Harrison Labs. Is -24dB or -30dB attenuation possible with a passive preamp before you run into channel imbalance?

I’d like to know if I can get more useable range on the volume knob of the A-100 using those preamps or are the simpler inline attenuators going to get me plenty of useful travel on the volume knob without having to add another box to my desk? I’d prefer to get to around 12:00-3:00 on the A-100 if possible, so I’m just not sure which option is going to get me there.


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## ckhirnigs113 (Dec 13, 2018)

I just learned something that might be useful to some A100 users here. I was considering getting some of those Harrison Labs -12dB in-line attenuators, but I was afraid they would not give me enough attenuation to really increase useable range on the A100 volume knob using my HD58X.

I asked John at JDS Labs how many decibels attenuation should be possible using his passive OL Switcher preamp before channel imbalance becomes an issue. He thinks -40dB should be possible, so this might be a much better option for those of us using relatively sensitive headphones with the A100 with jumpers installed.


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## KeithEmo (Dec 13, 2018)

A high-power attenuator on the output is the "right solution" if you have noise issues.

Let me clarify a few more things.

First, the idea of using the main amplifier outputs on the A-100, with the 220 Ohm series resistors, was sort of an homage to vintage audio gear.
In the old days, the 1970's and 1980's and before, this was the way the headphone outputs on almost all equipment were done.
At the time it was simply an easy way to add a headphone output without spending a lot of money on parts.
(The invention of low cost high quality separate headphone amp circuitry has made it simple nowadays to add a separate headphone amplifier for only a few dollars.)
However, recently, a lot of that vintage equipment has almost a cult following, and many people really like the sound of the headphone outputs on that old equipment.

Second, the exact effect this (the series resistors) will have on how a particular pair of headphones will sound depends on many factors.
The higher output impedance has two primary effects.
It delivers much less damping than usual - which will often result in bass that is less tightly controlled.
With some headphones the result will be a slight softening; with others there may actually be a slight increase in bass; with some the bass may become "quite flabby"; and many people might consider it to be in the direction of "tube sound".
In addition to this, it will result in an interaction between the amplifier output and the impedance of the headphones.
Because of this, in addition to differences due to damping, you may notice distinct differences in frequency response.
These differences will literally be different for every model of headphones.
(And, even more interestingly, if your headphones have existing bumps or dips in response, on the A-100 those may be reduced or increased...)

Finally, the difference between having the jumpers in and out will be significant with low impedance headphones... and minimal with higher impedance headphones.
The difference will usually be rather extreme with 32 Ohm headphones; far less with 300 Ohm phones; and barely noticeable with 600 Ohm headphones.
With high impedance headphones you'll be more likely to enjoy a significant improvement due to the massive amount of drive voltage available with the A-100.
However, with high impedance headphones, the effect of the jumpers on damping and frequency response will be much less...
With 32 Ohm headphones, the jumpers will alter the gain by 15 - 20 dB; however, with 300 Ohm headphones the difference caused by the jumpers will only be a few dB.
(So, specifically, if you have high impedance headphones, especially if you don't notice any noise, but simply want more volume control range, you should consider leaving the jumpers in and using attenuators on the inputs of the A-100.)




ckhirnigs113 said:


> @HiFiRebel I also didn’t have any hiss with my HD58X when I took the jumpers out. I just find the sound better with jumpers installed even with these sensitive cans. The hiss is not even noticeable when music starts playing.
> 
> To be honest, I didn’t find I had much more play on the volume knob when I took the jumpers out. This surprised me. I assumed I’d be able to get to 11-12:00 but probably didn’t get past 8:30-9:00. With the jumpers installed, I can get past the point of channel imbalance with my HD58X, but it obviously gets really loud really fast with a small turn on the knob.
> 
> ...


----------



## ckhirnigs113

@KeithEmo Thank you again for taking the time to explain things so thoroughly. With my 150ohm HD58X, how much more range on the volume knob do you estimate I'd gain using those -12dB inline attenuators you recommended? Right now I'd estimate I'm only getting about 5-10% use of the knob with jumpers installed. I'd really like to be able to get 50% use so I could make it to about 12:00 on the knob. 

Like I mentioned earlier, a passive preamp will get me up to -40dB attenuation, so it may work out better with one of those. As far as effects on sound quality, I'm assuming the inline attenuators are less likely to cause an issue vs the passive preamps.

This whole conversation may be moot if Jeremy from Garage1217 is able to produce the high-power attenuator box for the output side that solves all these little issues. I'm just impatient and keep thinking through my other options while I wait.


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## kukkurovaca

KeithEmo said:


> A high-power attenuator on the output is the "right solution" if you have noise issues.
> 
> Let me clarify a few more things.
> 
> ...



Have you guys considered including a switch on future amp models to change the output impedance without having to open up the case? I enjoy being able to tweak the impedance on my Phatlab Phantasy when using different headphones.



ckhirnigs113 said:


> @KeithEmo Thank you again for taking the time to explain things so thoroughly. With my 150ohm HD58X, how much more range on the volume knob do you estimate I'd gain using those -12dB inline attenuators you recommended? Right now I'd estimate I'm only getting about 5-10% use of the knob with jumpers installed. I'd really like to be able to get 50% use so I could make it to about 12:00 on the knob.
> 
> Like I mentioned earlier, a passive preamp will get me up to -40dB attenuation, so it may work out better with one of those. As far as effects on sound quality, I'm assuming the inline attenuators are less likely to cause an issue vs the passive preamps.
> 
> This whole conversation may be moot if Jeremy from Garage1217 is able to produce the high-power attenuator box for the output side that solves all these little issues. I'm just impatient and keep thinking through my other options while I wait.



I wonder if Garage1217 could actually include variable impedance settings on their attenuator. I think that for several of their amps, users can switch between three difference output impedance settings.


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## KeithEmo

Unfortunately, the A-100 has a tapered potentiometer, and I'm not sure exactly what the attenuation is at any point near the middle of it's travel. I think it should get you between 10:00 and 12:00.



ckhirnigs113 said:


> @KeithEmo Thank you again for taking the time to explain things so thoroughly. With my 150ohm HD58X, how much more range on the volume knob do you estimate I'd gain using those -12dB inline attenuators you recommended? Right now I'd estimate I'm only getting about 5-10% use of the knob with jumpers installed. I'd really like to be able to get 50% use so I could make it to about 12:00 on the knob.
> 
> Like I mentioned earlier, a passive preamp will get me up to -40dB attenuation, so it may work out better with one of those. As far as effects on sound quality, I'm assuming the inline attenuators are less likely to cause an issue vs the passive preamps.
> 
> This whole conversation may be moot if Jeremy from Garage1217 is able to produce the high-power attenuator box for the output side that solves all these little issues. I'm just impatient and keep thinking through my other options while I wait.


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## KeithEmo (Dec 13, 2018)

We may consider offering an actual switch in future models.
However, current plans are for a more normal high-powered headphone amp the next time around.

Variable output impedance would be difficult.
The type of potentiometers used on Volume controls are only good for a small fraction of a watt.
And potentiometers rated for more than that tend to be very large, very expensive, and not very smooth.
Therefore, it's much simpler to use multiple resistors (a rotary switch with several resistors would be practical).

(With an amplifier you can sometimes switch the output impedance by switching the feedback.
This is something that can be done at low power levels earlier in the signal path. )

The main drawback with "passive preamps" is that they are really a potentiometer.
Because of this, they tend to produce virtually no noise or distortion.
But, like most other types of analog Volume control, they tend to not track well at low settings.



kukkurovaca said:


> Have you guys considered including a switch on future amp models to change the output impedance without having to open up the case? I enjoy being able to tweak the impedance on my Phatlab Phantasy when using different headphones.
> 
> 
> 
> I wonder if Garage1217 could actually include variable impedance settings on their attenuator. I think that for several of their amps, users can switch between three difference output impedance settings.


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## ckhirnigs113

I could ask Jeremy at Garage1217 about the variable impedances, but I think, like @KeithEmo said, that would complicate the design and therefore make it more expensive. He is planning on including a switch to allow two different levels of attenuation, but I think the output impedances will both be relatively low.


----------



## OldMold

I just recently pulled the trigger on a new 2.0 audio setup and this is the piece of equipment that I look forward to the most. I've already got the rest in my hands, so now it's just a waiting game of when the a-100 is back in stock. Every morning, I check to see if the "Ships December 10" annotation on the Emotiva product page has been updated, but it still taunts me. The last time I felt this kind of excited impatience was probably 20 years ago as I patiently waited for Christmas morning in hopes of opening up a Nintendo 64.


----------



## KeithEmo

The simplest way to offer two levels of attenuation would be to change the "top" resistor in the L-pad.
Because of the values involved, I would expect both settings to offer similar low output impedances.



ckhirnigs113 said:


> I could ask Jeremy at Garage1217 about the variable impedances, but I think, like @KeithEmo said, that would complicate the design and therefore make it more expensive. He is planning on including a switch to allow two different levels of attenuation, but I think the output impedances will both be relatively low.


----------



## mushin1989 (Dec 15, 2018)

I think I might be losing my mind, I can't be sure -- I feel like I'm getting some muddiness in somewhere like the midbass range with the A-100. I'm using Argon Mk IIIs and the Jubilees primarily. I don't know why, but I feel like clarity is missing, or maybe that there is a kind of distortion going on. If anyone has any input, I'd like to hear it. I have fairly cheap speaker wires that I had to clumsily attach to some monoprice banana plugs (ugh, don't buy those) -- can issues with grounding cause subtle SQ issues like that? Maybe invest in a $20 pair of Micca speaker wires just to eliminate the possibility?

Lots of information about the potential benefits of attenuators and preamps in this thread and it is a little hard to sort out. I have headphones of all different resistances (32, 50, 80, and then 150) so I don't know how I'd be able to pick an attenuator without messing things up in an attempt to reduce the noise floor.

Is a preamp beneficial for the A-100 if you are getting your audio from your motherboard? In my case, I'm feeding USB audio from a Topping D10 into the A-100. What might the benefits, if any, be in trying hooking up something like the FX Audio TUBE-01 6J1 Preamplifier?

When I check out Equalizer APO, it says I'm clipping. I have no idea why and I don't necessarily hear a lot of clipping, but I do get unpleasant 'pops' and other such things from time to time. Things also start to sound rather messy at higher volumes, but that could be compression in the audio I'm listening to, I honestly don't know.

Apologies, lots of questions in here. Relatively new to this stuff and still learning.


----------



## KeithEmo

Never apologize; asking questions is how we learn things.

Here's a bit of history - in reverse.

Most modern gear has a separate headphone amp for its headphone output.
This may be made out of several discrete transistors, just like a little power amp, or it may all be in an integrated circuit - usually the latter.
These little amps are usually very quiet, very low in distortion, and, since they're connected directly to the headphones, they provide pretty good damping.
Also, because of that low output impedance, they don't interact with the headphones - the amp itself sounds the same with different headphone models.
(Output impedances range from very low up to 5 Ohms or so.)
With current parts these little amps only add a few dollars to the cost - so virtually all gear with a separate headphone output uses them.
The only real down-side is that they usually don't have much power or voltage - so they don't do well with high impedance headphones or really low efficiency models.

In contrast, most vintage gear did NOT have a separate amplifier for the headphones.
Back then, parts were more expensive, and there simply wasn't as much interest in headphones.
Therefore, most vintage gear simply connects your headphones to the main speaker outputs through a series dropping resistor.
This requires a single low cost part... so it's easy and cheap.
However, there are several drawbacks to doing it that way.
Speaker outputs usually have more noise and more distortion than a purpose designed headphone amp (and they're both more noticeable with headphones).
The output impedance in that configuration is equal to the value of the series resistor you use - and so is usually quite high (the A-100 is typical at 220 Ohms).
This high output impedance causes two things - both of which affect low impedance headphones more than high impedance ones.
First off, because damping depends on the ratio between the impedance of the amp and the impedance of the headphones, there is MUCH less damping.
Second, the output impedance interacts with the impedance of the headphones.... so the amp has a "slightly different personality" with different models of headphones.

There were several things that motivated us to design the A-100 the way we did.

1) Certain early planar headphones have a very low impedance, and are VERY inefficient, and in fact have needs more like speakers than headphones. This prompted many people to start running them directly from the outputs of a "speaker amplifier" using a special adapter cable. We noticed that many people were using the previous version of the A-100, the Mini-X, that way. (There are only a few models of headphones that really need all that power these days, but many people noticed that there were benefits even with normal high impedance headphones, or with other hard to drive models.)

2) Even though they have some drawbacks, the headphone outputs on vintage equipment have developed a bit of a cult following. Some people LIKE the way they interact with the headphones, so each model has its own characteristic sound on each different amp. (There are whole threads on Head-Fi dedicated to "listening to headphones on vintage gear).

Therefore, we decided to use a "vintage style headphone output" on the A-100.

Here are a few of the details worth noting....

1) 
With the jumpers out the A-100 has an output impedance of 220 Ohms.
This means that, like with vintage equipment, it applies very little damping to the headphones (many will sound different because of this - which could be good or bad).
Likewise, the impedance of the amplifier will actually interact with the impedance of the headphones (again, the effect this has will vary with different headphones).
These effects will be major with low impedance headphones and relatively much less with high impedance headphones.
The A-100 will have plenty of voltage to drive even very high impedance headphones very well.
(The A-100 has much less noise and distortion than most vintage equipment - so these are much less of an issue).

2)
With the jumpers IN, the main outputs of the A-100 are connected directly to your headphones.
if you had headphones that had to be connected directly to the speaker outputs on an amplifier - this is the same thing.
With the jumpers IN the gain of the entire system is very high - which means more noise and more power.
(If your headphones are very inefficient, you'll need the power, and you won't notice the noise. With more normal headphones this may be a bad choice.)

Now, just a little bit about how amplifiers work inside.
When the audio signal enters the A-100, it goes through a voltage divider (the Volume control), and then on to what is basically a power amplifier.
The amplifier portion always boosts the voltage by the same amount; the Volume control adjusts the level by cutting down the level of the signal going in.
(This is how virtually all amplifiers with volume controls work.)

Now... if you notice a lot of noise.....
(this is more likely to occur with the jumpers in and the resistors bypassed).

IF the noise remains the same, regardless of where you set the Volume control on the A-100, then you're hearing the internal noise of the A-100's amplifier itself.
If that's the case, then the only way to reduce it is to reduce the level at the OUTPUT - by putting a power attenuator between the output and your headphones.
(Or, if your headphones are very sensitive, perhaps you should try putting the jumpers in, or perhaps you just don't need an amplifier this powerful.)

IF the noise level changes when you adjust the Volume control on the A-100, then that means that the noise is coming in from the previous component.
If that's the case, then putting a line-level attenuator between the previous component and the INPUT of the A-100 will help.
Likewise, if you simply can't turn the Volume control on the A-100 up more than a few degrees, the best solution is an attenuator on the INPUT of the A-100.

Your Topping D10 is a DAC.
Therefore, you are NOT feeding the A-100 audio from your motherboard.
Your Topping D10 has replaced the sound card on your motherboard and is acting in its place.

However,your D10 doesn't have its own volume control, so....
If the noise goes up and down with the Volume setting on the A-100 then you're hearing the noise floor on the output of the Topping.
If that's the case, then putting an attenuator between the Topping and the A-100 should help.
If the noise remains the same, regardless of where you set the Volume on the A-100, then you're hearing the noise floor on the A-100 itself.
If so, then putting an attenuator between the output of the A-100 and your headphones will improve matters.
(But, if that's the case, maybe you should simply consider using a less powerful amplifier with those headphones instead.)

If you put a preamp between your Topping and the A-100 several things will happen.
You will add another opportunity to control the level - which may or may not help in your case.
Whatever noise and distortion this new device creates will be added to whatever is already there.
Tube equipment produces certain types of distortion that some people find pleasing.
Therefore, adding a tube preamp will almost certainly add coloration to the sound.... but you might find it to be pleasant.

If the equalizer software on your computer reports clipping then that will definitely make the sound quality worse...
And it's something that has to be handled on the computer by the player software.
(The computer doesn't know what the DAC or the amp are doing; if it reports clipping then that means that it is the program doing the clipping.)
You could try turning the level on the player software down a bit - and the level on the A-100 up a bit.

The standard advice for best sound quality would be to "run the computer volume at full" and use other Volume controls to lower it.
However, if something in the software is actually clipping, then you should forget that advice, and turn your player software down until it ISN'T clipping.
It's not uncommon for player programs to allow you to choose equalizer settings that may sometimes cause them to clip.
(If the sound files themselves, or the video you're playing, are simply themselves clipped, there's not much you can do about it.)

It's extremely UNLIKELY that speaker wires will make any difference.... unless they're actually frayed or broken.
A LOOSE connection can cause distortion... but is quite unlikely to cause "grounding issues".



mushin1989 said:


> I think I might be losing my mind, I can't be sure -- I feel like I'm getting some muddiness in somewhere like the midbass range with the A-100. I'm using Argon Mk IIIs and the Jubilees primarily. I don't know why, but I feel like clarity is missing, or maybe that there is a kind of distortion going on. If anyone has any input, I'd like to hear it. I have fairly cheap speaker wires that I had to clumsily attach to some monoprice banana plugs (ugh, don't buy those) -- can issues with grounding cause subtle SQ issues like that? Maybe invest in a $20 pair of Micca speaker wires just to eliminate the possibility?
> 
> Lots of information about the potential benefits of attenuators and preamps in this thread and it is a little hard to sort out. I have headphones of all different resistances (32, 50, 80, and then 150) so I don't know how I'd be able to pick an attenuator without messing things up in an attempt to reduce the noise floor.
> 
> ...


----------



## therckr123

Is this normal for it to be popping out like that?


----------



## ckhirnigs113

@KeithEmo I have a general question about amps and their gain settings. I have an iFi iCan SE amp alongside my A-100. It has 3 different gain settings. I can get to an adequate volume on low gain mode with my notoriously hard-to-drive T-X0 planar headphones (a Fostex T50RP variant). For so called “power hungry” headphones is there an objective reason to use a higher gain setting if I’m already at a high enough volume level?

What is the benefit of the 50w the A-100 has vs the 4w the iCan SE is capable of if the max power handling of my headphones is only 3w. I do realize neither the A-100 or iCan SE can push that wattage with my 50ohm headphones and of course I will never get anywhere near max volume on either amp. Is it the effortless way a super powerful amp can handle power swings vs a lower powered amp? Or is there some other reason a planar sounds better with a grossly overpowered amplifier?


----------



## KeithEmo

It's just a bolt.... and they vary slightly in length.
As long as the metal of the bolt dowsn't touch the metal of the top cover it's fine (and that's what the little rubber pad on top is there for).



therckr123 said:


> Is this normal for it to be popping out like that?


----------



## KeithEmo

The short answer to your question is that it probably doesn't matter.

Here's the way it works...
In amplifier design there are some tradeoffs between gain and noise.
Therefore, if you had very sensitive headphones, you might actually get somewhat lower noise on a lower gain setting.
So headphone amps designed to work with a wide range of headphones, from insensitive planars to absurdly sensitive IEMs, often offer a gain switch.
(If they did it right they're actually changing a setting inside the circuit to trade between gain and noise.)

The fact is that most headphone amps, especially those that don't cost a fortune, are VERY low power... usually in the 0.1 watt to 0.5 watt range.
And, to be quite honest, that's more than enough for most 30 Ohm and 50 Ohm headphones.
However, because those sorts of amplifiers couldn't drive low efficiency planars well at all, people started using "speaker amplifiers" to run them.
Usually with some sort of custom or homemade adapter cable that connected to the speaker terminals.
(Their requirements are more like speakers than like most other headphones.)

Now, high IMPEDANCE headphones are a different animal altogether.
High impedance headphones don't use much power at all... and they're actually ridiculously EASY to drive.
However, if you want to play them at all loudly, they need quite a bit of VOLTAGE....
And, since most little headphone amps run on a relatively low voltage supply, many of them have trouble there as well.
(The headphone output on a typical phone delivers something like a volt or two... and that's a serious limitation for driving 300 ohm phones.)

And, as I mentioned in a previous posting, almost all vintage equipment powered its headphone output from the main amplifiers - through a dropping resistor.
And, because of the interaction between the amp and the headphones, they just plain sounded a bit different.
(By "proper modern standards" they are less accurate - but a lot of people simply_ like_ that _vintage sound_.)

The answer to your question is that, for even most inefficient planars, a good quality 5w amplifier with a low impedance output would be fine.
And, for most high impedance headphones, an amplifier that delivered 0.5 watts - but could deliver 15 or 20 VOLTS would be fine.
And, for people who want that vintage sound, you could take an amp somewhere in between and add a pair of 220 Ohm resistors and you'd be fine.

The bottom line is that we made the A-100 so powerful because it was originally designed to run SPEAKERS.
We then added vintage style headphone outputs as a sort of homage to the cult following that the headphone outputs on vintage equipment have acquired recently.
And we noticed that many people were using its predecessor to run low-efficiency planars.... using specially made adapter cables.... so we added the jumper option to make doing that easier.
And many people noticed that, even though they didn't need that much power, the 25 VOLT maximum output of the A-100 works really well with high impedance headphones too.
And, as it turns out, because of its exceptionally economical PRICE, the A-100 is pretty much the most economical high quality solution for EACH of those requirements.
(And, in fact, it does each of them as well or better than a lot of units costing far more designed to do just one of them.)

However, for your application, a well designed 5w amplifier would do everything you want just about as well as the A-100.

And, yes, sometime soon we will be coming out with an Emotiva _headphone_ amp....
It will be Class A, and deliver somewhere near 5 watts/channel, and have a gain setting, and all that good stuff.....
But I won't promise it will be quite as economical as the A-100....
(Sorry... no more details yet...   )




ckhirnigs113 said:


> @KeithEmo I have a general question about amps and their gain settings. I have an iFi iCan SE amp alongside my A-100. It has 3 different gain settings. I can get to an adequate volume on low gain mode with my notoriously hard-to-drive T-X0 planar headphones (a Fostex T50RP variant). For so called “power hungry” headphones is there an objective reason to use a higher gain setting if I’m already at a high enough volume level?
> 
> What is the benefit of the 50w the A-100 has vs the 4w the iCan SE is capable of if the max power handling of my headphones is only 3w. I do realize neither the A-100 or iCan SE can push that wattage with my 50ohm headphones and of course I will never get anywhere near max volume on either amp. Is it the effortless way a super powerful amp can handle power swings vs a lower powered amp? Or is there some other reason a planar sounds better with a grossly overpowered amplifier?


----------



## therckr123

KeithEmo said:


> It's just a bolt.... and they vary slightly in length.
> As long as the metal of the bolt dowsn't touch the metal of the top cover it's fine (and that's what the little rubber pad on top is there for).


The problem is that when I was putting the cover back on, the bolt protruded so much that it dented the top where the bolt touches it. That is what really worried me.


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## ckhirnigs113

@KeithEmo Thank you for that in depth explanation! I think I'll have to do some more comparisons between my 4W iCan SE and the 50W A-100. The iCan SE has a 15V DC power supply, so I assume that's the max voltage it can provide. From what you explained, I'm assuming the voltage available should be the same regardless of gain setting, correct? Therefore with my planars, there should be no advantage using medium or high gain versus low gain as long as I can get adequate volume, right?


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## bequietjk

Where exactly can we find the voltage output on an amp spec list?  Are the volts that are needed for higher impedence cans coming from the power supply, like the 25volts Keith mentioned coming from the A100?


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## mushin1989 (Dec 27, 2018)

Keith, thanks for your thorough and thoughtful reply.

I do run speakers. Sony SSCS5s, in fact. I got them for $75 or so on BF (they're selling on Amazon right now for $73). They're punch way above their weight despite the fact that not a ton of people are talking about them. The Emotiva drives them quite well, and would do even better if I had a subwoofer to help them out so the lower frequences could be something else's job.

I don't see anything about subwoofers on the A-100 product page, but I assume the RCA line out does the job the absence of LFE?

I think in some cases the issue with SQ may have been that I wasn't letting the amp warm up. Or me listening too critically/being paranoid because I did not buy it new.

As I noted, my setup is a PC running USB into a Topping D10 out into the A-100. Is there any way I can use the trigger function? The D10 has RCA in/out and S/PDIF. There doesn't seem to be anything I can plug into the Topping to accomplish this. Wondering what kind of input/output I'd need on a source device. My PC has an unused 3.5'' jack, but it wouldn't do much good to have it trigger off the PC's Realtek drivers. I confess total ignorance to audio triggers here as I haven't done anything with them before.

**BTW, if any of this has been answered in a previous post, please just direct me to it, not trying to waste anyone's time!**



KeithEmo said:


> Never apologize; asking questions is how we learn things.
> 
> Here's a bit of history - in reverse.
> 
> ...


----------



## HiFiRebel

I got my Argon Mk3 headphones and am happy to report that there is absolutely no floor noise with them after installing jumpers in. However, it is a different story with my Philips Fidelio X2. Without jumpers, dead quiet, no noise floor at all. With jumpers installed the noise floor is very noticeable when no music is playing.


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## Yevgen Chupak (Jan 11, 2019)

HiFiRebel said:


> I got my Argon Mk3 headphones and am happy to report that there is absolutely no floor noise with them after installing jumpers in. However, it is a different story with my Philips Fidelio X2. Without jumpers, dead quiet, no noise floor at all. With jumpers installed the noise floor is very noticeable when no music is playing.


Any measurable difference with or without jumpers on Argons soundwise? with the same volume? Still, hate to put that jumper... using my A100 not only with Argons... and it will be too much for my other cans.


----------



## HiFiRebel

Yevgen Chupak said:


> Any measurable difference with or without jumpers on Argons soundwise? with the same volume? Still, hate to put that jumper... using my A100 not only with Argons... and it will be too much for my other cans.


I'm not sure about "measarable" but to my ears the bass sounded thinner without jumpers in on Argons. However, I spent listening to them without jumpers for maybe 10-15 min. I really wish it was some kind of switch instead of jumpers. I could then just switch between when listening to different headphones.


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## ckhirnigs113

I have not used my Argon MK2's with the A-100 with the jumpers taken out yet. I went ahead and put the jumpers in before I even received my Argons. I assumed the extra power on tap is the whole reason for using the A-100 with headphones. I have read that planar headphones are not as sensitive to impedance mismatching/damping factor as dynamic headphones, so there might not be too much of an effect on the Argons after all. I'll be sure to try my Argons with the jumpers taken out one of these days and report back. 

I did try my HD58X with jumpers taken out, and the bass got much more bloated sounding. I much preferred the sound with the jumpers installed. The problem was that I had so little play on the volume knob. Despite that, I still use the A-100 with jumpers installed.


----------



## HiFiRebel

One of the reasons I ordered a DAC with a pre-amp is to gain more volume control on the A-100 amp.


----------



## Yevgen Chupak

I have Fostex A4BL as an Amp/Dac and it's volume control also controlling not only headphones out but RCA out as well...


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## bequietjk (Feb 5, 2019)

So EMO...

Now that the THX AAA 789 is out... can we get a contender, please!

ETA ON THE NEW HEADPHONE AMP PLEASE!!!!!!???


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## Yevgen Chupak (Jan 21, 2019)

I have my emotiva connected to Fostex A4BL... The source is Mac Pro via USB... and in auto signal detection mode it's constantly turning itself off. While im watching the movies in VLC or watching Youtube or facebook videos... in both Chrome and Safari. Google Play Music player Desktop is affected as well.

Tidal mac app is ok.

Any solution for this?


----------



## IBJamon

Yevgen Chupak said:


> I have my emotiva connected to Fostex A4BL... The source is Mac Pro via USB... and in auto signal detection mode it's constantly turning itself off. While im watching the movies in VLC or watching Youtube or facebook videos... in both Chrome and Safari. Google Play Music player Desktop is affected as well.
> 
> Tidal mac app is ok.
> 
> Any solution for this?


That sounds like a warranty issue to me.  You may want to call Emotiva.  Their support is pretty good.


----------



## KeithEmo

The auto-detect mode on the A-100 turns on when the audio coming into the amp exceeds a certain level...
And it remains on as long as the average level remains above a certain level.
If the average level falls below the threshold it will turn off.

So, if what you're listening to is too quiet, for too long, the amp will turn off.
If this happens, then simply set the amp to "always on", and it won't happen.
The A-100 doesn't really draw enough power to worry about when it's idling.
(The fact that this only happens with certain sources seems to prove that there's nothing wrong with the amp.)



Yevgen Chupak said:


> I have my emotiva connected to Fostex A4BL... The source is Mac Pro via USB... and in auto signal detection mode it's constantly turning itself off. While im watching the movies in VLC or watching Youtube or facebook videos... in both Chrome and Safari. Google Play Music player Desktop is affected as well.
> 
> Tidal mac app is ok.
> 
> Any solution for this?


----------



## IBJamon

You know, I just had a crazy experience with this amp this evening.  It turns out that my IEMs were dying, so I got a new set, and my wife coincidentally ordered herself a new set based on what she heard me talk about.  So I have access to two brand new KZ IEMs: the ZS7 and the ZS10.  (They sound more similar than different, though the 7 is a bit darker and 'more refined' with the 10 being a bit 'livelier', though with some sources it sounds a tiny bit hollow.)

When I play the ZS10 through the Emotiva it sounds simply fantastic.  No complaints at all.  (I use it jumpered with a voltage divider that I posted about many pages back.)  When I play the ZS7  (and the ZS6 that's flaking out), it sounds like the bass driver is not working at all.  It sounds distant, distorted, and tinny.  It's amazing how bad it sounds (while they sound great on my LG phone's DAC/AMP or my Topping NX4, or even directly to my laptop).  (I tested it without my adapter, aka direct mode, and it didn't change anything.  Of course I was very careful with the volume knob.)  One major difference I notice is the all metal shell on the ZS6/7, vs. the plastic one for the ZS10.  Is there something different about how the Emotiva grounds that might short circuit these IEMs vs. a portable device?


----------



## Rchandra

With the jumpers installed and leaving my headphones plugged in with it on with no music playing can it damage the headphones with the amount of power going through them?


----------



## Yevgen Chupak

Rchandra said:


> With the jumpers installed and leaving my headphones plugged in with it on with no music playing can it damage the headphones with the amount of power going through them?


No


----------



## Yevgen Chupak

KeithEmo said:


> The auto-detect mode on the A-100 turns on when the audio coming into the amp exceeds a certain level...
> And it remains on as long as the average level remains above a certain level.
> If the average level falls below the threshold it will turn off.
> 
> ...



Gotcha tnx. So what i need is to keep my volume on that specific lvlv and autodetect should work just fine.


----------



## KeithEmo

When nothing is playing the power going to your headphones is zero and it's not going to bother anything.

_HOWEVER_, under most circumstances, that is a _REALLY BAD HABIT_ to get into if you have relatively low impedance headphones.......
All you need to do is forget they're plugged in, and turn the volume up too high, and you can easily smoke your headphones in a permanent sort of way.

At a very minimum you should get in the habit of turning the volume on the amp all the way down when you end your listening sessions.



Rchandra said:


> With the jumpers installed and leaving my headphones plugged in with it on with no music playing can it damage the headphones with the amount of power going through them?


----------



## Rchandra

With the jumpers installed how much power is going to my headphones at noon on the dial?


----------



## IBJamon

Rchandra said:


> With the jumpers installed how much power is going to my headphones at noon on the dial?


That number totally depends on the headphones and what impedance they have.  According to the specs page:

Power Output (headphone output; direct drive mode) 
(requires internal jumper; USE WITH CAUTION):
8 Ohms:  50 watts / channel
33 Ohms:  12 watts / channel
47 Ohms:  8.5 watts / channel
150 Ohms:  2.6 watts / channel
300 Ohms:  1.3 watts / channel
600 Ohms:  0.6 watts / channel

That is maximum power, and the knobs are logarithmic.  But I would Never Ever use the headphones with them turned up half way as a starting point.  You always start with them very low, and slowly increase as needed.  Otherwise you are just asking for blown headphones.


----------



## Rchandra

IBJamon said:


> That number totally depends on the headphones and what impedance they have.  According to the specs page:
> 
> Power Output (headphone output; direct drive mode)
> (requires internal jumper; USE WITH CAUTION):
> ...



I'm using a sony Z1R..I normally go to almost noon at times but wonder if it's damaging my driver's lol


----------



## IBJamon

Rchandra said:


> I'm using a sony Z1R..I normally go to almost noon at times but wonder if it's damaging my driver's lol



If you ears are not blown out, it's probably fine.  All I can say is that if you switch sources and the other one is substantially louder than another (say a quiet song vs. a loud one or a youtube vs. a game) you may be in for a rude awakening.  But I wouldn't worry about it if your ears are not on fire.


----------



## IBJamon

I just looked up those headphones.  Very impressive (and expensive!!!).  You can damage those, but I'm sure they can take quite the beating.  Enjoy!


----------



## Rchandra

I may have messed something up on them with the loud volumes lol something is a bit off on the left side lol but that could be my brain more then anything else


----------



## HiFiRebel

Can I connect speakers like these to A-100?


----------



## IBJamon

HiFiRebel said:


> Can I connect speakers like these to A-100?


Absolutely.  A few extra watts is nothing to worry about.  Unless you plan to run then full blast for hours on end, they should work perfectly.


----------



## HiFiRebel

IBJamon said:


> Absolutely.  A few extra watts is nothing to worry about.  Unless you plan to run then full blast for hours on end, they should work perfectly.


Thank you


----------



## meowKittieh

Hi All!

Earlier today I lurked through the last 40 pages of this thread because I'm really interested in the A-100. After that, I pulled the trigger and picked one of these up on Amazon. 

Like many other posters I was struck by Mr. Zeos's enthusiasm and it seemed to do him well with the Argons, which I've ordered. I think I need to stop watching his channel. Aside from Z-reviews, one of the things that pushed me over the edge on buying this was seeing the designer chip in on this thread. In my limited experience it's pretty rare to see THE hardware designer come in and offer up info on the design and insights on how to use it. So cool!

Anyway, I figured I'd share some of my thoughts on the amp. Mainly about the noise, as to me this is a defining factor on how useful this is as a headphone amp. It sort of makes sense to me why there _could_ be noise with jumpers placed. AND, since I've had two fingers of Arberlour, I'll type out how I see things... please excuse egregious grammatical or mathematical errors or if I'm being too obvious or pedantic...

The SNR on this thing is pretty darn good at 110dB (at full scale output... sqrt(50Wrms*8Ohms)=20Vrms). However, if you're just driving some 16 ohm IEMs your true "full scale" may very well be less than 1Vrms (50-ish mW). Since you're making use of only 5% of the actual ~20V full scale (or at most 20*log10(1/20) = -26dB) your relative SNR will be closer to 110dB - 26dB = 84dB. The T50RPs, being beasts at 3W / 50ohm, would use up more like 12V. Assuming you REALLY enjoy listening to them at MAX volume, you'd be making use of 60% of the amplifier headroom (only ~4.5dB down from full scale) and your relative SNR would be up to ~106dB. I think a lot of this is dependent on how YOU hear, but, loosely equating lower effective SNR to higher amounts of audible noise, you should hear more noise with more sensitive and lower resistance headphones... that is, if you hear any noise at all. This also explains why adding series resistance decreases noise as you'd be using more output voltage.

Luckily for me, the A-100 is going to be pulling double duty and its day job is going to be driving some Klipsch RP-15ms... if the hiss is audible w/my headphones, I'm still getting at least 50% of the intended use out of this thing. I will post again in a few months with my actual experiences with the A-100 when I've finally got those lovely Argons in-hand.

Ramble over. Glad to be on the forum!


----------



## LHS

Has anyone fixed the hiss issue? My jumpers are in place. There is an extremely audible hiss coming out of my LCD-X. No hiss coming from my speakers from the same source. Do I have a dud? 

I've tried moving USB ports and power cables for the A100 and my audio interface.


----------



## meowKittieh

For whatever it's worth, my A-100 just arrived and I'm also getting a slight hiss. I can just barely hear it coming out of my RP-15M tweeters, sitting ~3' away. Turning off all nearby potential sources of EMI, I'm still hearing it. Also tried pulling source and output cables to no avail. I'm also getting a slight hiss my HD6XX w/o the jumper placed. Just for fun I downloaded a spectrum analyzer app for my phone. Moving it closer to and away from my tweeter, it appears the noise is broad spectrum and could indeed be the amp noise floor (vs. picking up hum from power).

@LHS You're par for the course IMO...

I'm going to use it for a few days and return if it's not to my liking. One of the perks of ordering from Amazon, I guess. At least this amp/speaker setup beats the every loving crap out of my Creative Pebble speakers.


----------



## Rchandra

The hiss is normal.. You just have to remember with great power comes great responsibility.. You can easily mess up your headphones with this amp if not used properly.. The farthest I've gotten with jumpers on is 12 o'clock with the hd800S


----------



## LHS

Rchandra said:


> The hiss is normal.. You just have to remember with great power comes great responsibility.. You can easily mess up your headphones with this amp if not used properly.. The farthest I've gotten with jumpers on is 12 o'clock with the hd800S



How audible should it be though? The hiss is very loud and can be heard clearly when most music is playing


----------



## Rchandra

It will be audible and really noticable on more sensitive cans.. I honestly only use it for my harder to drive cans.. The hiss should go away as you listen to music and raise the volume.. How loud do you have it set up on the source? For me I have it 2 clicks to Max and then I turn the knob as needed.


----------



## IBJamon

Those Klipsch bookshelves will expose hiss on almost any amplifier.  It's because of the crazy-high sensitivity of the horns.  I use far less efficient bookshelves (Pioneer BS22s) at my desk and they are silent.  I can't speak to those headphones as I don't have a pair so I don't know how efficient they are.


----------



## LHS

Rchandra said:


> It will be audible and really noticable on more sensitive cans.. I honestly only use it for my harder to drive cans.. The hiss should go away as you listen to music and raise the volume.. How loud do you have it set up on the source? For me I have it 2 clicks to Max and then I turn the knob as needed.



I mean the LCD X are 300ohm correct? I have to turn the source up to max and then the amp up about half way or more. I honestly can't stand how loud the hiss is on mine...should I get a replacement or is there another amp that's similar that can power speakers and headphones?


----------



## HiFiRebel

Jumpers removed my Philips Fidelio X2 headphones are silent (ie no hiss). Install jumpers - hiss is quite noticeable. Those are very easy to drive headphones. 
With Argon Mk3 headphones (so not so easy to drive), I get no hiss with or without jumpers. 

Hence my advice is, install jumpers ONLY for hard to drive headphones.


----------



## LHS

Im not sure where I got the 300ohm for the LCD-X's from...lol. They are 20ohm and should be incredibly easy to drive. I'm going to uninstall the jumpers this evening and see if that makes a difference. I believe it should as with the jumpers installed the A-100 produces like 25 watts of power at 20ohms!


----------



## meowKittieh

IBJamon said:


> Those Klipsch bookshelves will expose hiss on almost any amplifier.  It's because of the crazy-high sensitivity of the horns.  I use far less efficient bookshelves (Pioneer BS22s) at my desk and they are silent.  I can't speak to those headphones as I don't have a pair so I don't know how efficient they are.



That makes sense - I was previously running the RP-15s off of a 6W tube amp (tubecube 7) and getting good volume levels in my living room. I still wasn't sure whether to expect them to be sensitive enough to pick up on the A-100 noise floor, but I accept that's what's happening. Overall I'm pretty happy with the amp, and the noise really is barely audible and I mostly notice it only when I'm looking for it. I'm loving the heavy metal front plate and overall build.


----------



## LHS

Yeah removing the jumpers solved my issue and it sounds like there is still plenty of power left if needed for my LCD-X's! Thanks guys for the suggestion.


----------



## rsvette12

Hi Guys you that have all this humming noise going on well seems its not the unit for me anyway get one of these Tripp lite surge protectors and gets incredible reviews - maybe there is a cheaper version that will work with less plugs it has advanced noise protection - I have an older very expensive version but this should work fine - no noise anymore - I was using it on my TV and said hmm let me try it on my amps - preamp is little dot iii and amp is emotiva a-100 all good now

https://www.amazon.com/Tripp-Lite-P...ripp+lite&qid=1551650491&s=electronics&sr=1-1


----------



## PopZeus

After realizing I much prefer the Elex with a warmer overall sound, I decided to use the A-100 for both powering my speakers and headphones. And for the cost, it's shockingly great.


----------



## HiFiRebel

After buying and connecting speakers to my A-100. I get now a very slight clicking when I have my headphones connected. I had to move a few things around to fit the speakers onto the desk. It sounds like some kind static electric interference, as sometimes when I click the main light on, I can hear a click in my headphones as well. It is very faint clicking but pretty much constant and annoying. I can't hear it when something's playing. It's not the speakers as I still get it when I disconnect speakers. Any ideas please?


----------



## HiFiRebel

THe crackling intensifies when network traffic intensifies, like when I open a website for example. It sounds exactly like crackling on a landline phone back in the days.


----------



## HiFiRebel

In case anyone else have a similar problem in future. I have sorted out the problem by replacing the old surge protected extension lead with a new one. It must have been dying. I have both my DAC and amp (and PC) connected to it, so I'm not sure which of those suddenly started to dislike the old one, but now all of them are happy with clean power and issue is gone.


----------



## LHS

HiFiRebel said:


> In case anyone else have a similar problem in future. I have sorted out the problem by replacing the old surge protected extension lead with a new one. It must have been dying. I have both my DAC and amp (and PC) connected to it, so I'm not sure which of those suddenly started to dislike the old one, but now all of them are happy with clean power and issue is gone.


I was gonna say as I was reading the thread, that sounded like the exact power issue I had with this amp. Honestly getting a powered USB hub helps tons


----------



## HiFiRebel

LHS said:


> I was gonna say as I was reading the thread, that sounded like the exact power issue I had with this amp. Honestly getting a powered USB hub helps tons


Thanks, I'm happy with the way things are at the moment really. As it is now I'm running out of spare USB ports in my desktop PC anyway (and I have quite a few of them).


----------



## gwertheim

What is the best way to put a volume mark on the knob? Are there any other reference marks I can use to make the mark more visible? 

I am planning to pick one up in the next couple of months but I don't want to turn it too loud for obvious reasons


----------



## HiFiRebel (Apr 3, 2019)

gwertheim said:


> What is the best way to put a volume mark on the knob? Are there any other reference marks I can use to make the mark more visible?
> 
> I am planning to pick one up in the next couple of months but I don't want to turn it too loud for obvious reasons


I just cut a small triangle out of a plain white sticker and stuck it on. It's not permanent, so I can always remove it if selling, it's perfectly visible and cheap and easy to do.


----------



## KeithEmo

I haven't tried them on that knob...

But Sharpie markers come in metallic silver and gold... and they work pretty well on black surfaces.
(A single dot near one edge of the knob should do it.)



gwertheim said:


> What is the best way to put a volume mark on the knob? Are there any other reference marks I can use to make the mark more visible?
> 
> I am planning to pick one up in the next couple of months but I don't want to turn it too loud for obvious reasons


----------



## gwertheim

KeithEmo said:


> I haven't tried them on that knob...
> 
> But Sharpie markers come in metallic silver and gold... and they work pretty well on black surfaces.
> (A single dot near one edge of the knob should do it.)



Question for you, why wasn't a volume indicator put on the knob?


----------



## KeithEmo

Interesting question.... and there isn't any specific reason that I know of.

All of our other gear hear at Emotiva uses encoders on the Volume control.
(With an encoder, you can't tell the setting from the position of the knob, so you don't put a reference mark on the knob.)

Since the A-100 is pretty much the only component we currently make that uses a potentiometer-style Volume control.... 
I guess nobody realized it would be nice to add that on this particular Volume knob.



gwertheim said:


> Question for you, why wasn't a volume indicator put on the knob?


----------



## gwertheim

KeithEmo said:


> Interesting question.... and there isn't any specific reason that I know of.
> 
> All of our other gear hear at Emotiva uses encoders on the Volume control.
> (With an encoder, you can't tell the setting from the position of the knob, so you don't put a reference mark on the knob.)
> ...



Kind of makes sense, I am going to get one this summer, since I am in Canada, going to see if the dollar improves because I am going to take a beating on duties


----------



## Feilong4

These are not the jumpers, correct?

 

I can't seem to find a definitive image of the jumpers.


----------



## KeithEmo

This is what the jumpers look like.... they are a little square bit of plastic - about 1/4" square and 1/8" thick - with some metal inside.
The end with the big opening gets pressed down over the two pins - and the little metal contact inside connects the two pins together.
(They actually come in a variety of colors, and there are shorter ones, and ones with an extra tab on top to hold onto, but these black ones are the most common.)

They are very commonly used in computers (computers commonly use two sizes - these are the bigger ones).
There should be a couple of them in the little baggie that came with the A-100.



Feilong4 said:


> These are not the jumpers, correct?
> 
> 
> 
> I can't seem to find a definitive image of the jumpers.


----------



## Feilong4

KeithEmo said:


> This is what the jumpers look like.... they are a little square bit of plastic - about 1/4" square and 1/8" thick - with some metal inside.
> The end with the big opening gets pressed down over the two pins - and the little metal contact inside connects the two pins together.
> (They actually come in a variety of colors, and there are shorter ones, and ones with an extra tab on top to hold onto, but these black ones are the most common.)
> 
> ...



Ah ok thank you!

I just received a second-hand A-100 BasX today, and they didn't come with the jumpers in that case.

Seeing that you are a Member of the Trade of Emotiva, is it possible for Emotiva to send a couple of them to me?


----------



## gwertheim

Just got my a-100 and I couldn't be happier. I have a pair of t60rp's and they sound fantastic with this amp. 

Now I need another pair of higher impedance headphones so I have an excuse to install the jumpers


----------



## Baten

gwertheim said:


> Just got my a-100 and I couldn't be happier. I have a pair of t60rp's and they sound fantastic with this amp.
> 
> Now I need another pair of higher impedance headphones so I have an excuse to install the jumpers


The jumpers can be installed perfectly fine with T50RP/T60RP  moar powar.


----------



## Yevgen Chupak

Baten said:


> The jumpers can be installed perfectly fine with T50RP/T60RP  moar powar.


but it's gonna be higher noise floor


----------



## Baten

Yevgen Chupak said:


> but it's gonna be higher noise floor


_That's_ _true_


----------



## ckhirnigs113

Yevgen Chupak said:


> but it's gonna be higher noise floor


I don’t notice the noise floor with the jumpers installed when using my Mod House Argons (based on T50RP MKII). I feel the sound is better with jumpers installed. I’d recommend giving it a try.


----------



## gwertheim

ckhirnigs113 said:


> I don’t notice the noise floor with the jumpers installed when using my Mod House Argons (based on T50RP MKII). I feel the sound is better with jumpers installed. I’d recommend giving it a try.



It is plenty loud for me right now. Might try it down the road when I have a bit more time to play around with it


----------



## Baten

gwertheim said:


> It is plenty loud for me right now. Might try it down the road when I have a bit more time to play around with it


It's really easy to do/undo btw


----------



## thebkt

As an FYI, I've had my A-100 for a few months now and am completely satisfied with it.  It's a shame it doesn't have additional analog inputs, but the sound quality is great.  I've been using it to power a pair of ELAC UB5's which sound absolutely fantastic with the A-100, using my old Mimby as a DAC.  At some point I'll use it for headphones, but atm, it's too far away from the couch.


----------



## gwertheim

Baten said:


> It's really easy to do/undo btw



I've already opened it up to take a look around at around 1 am before hooking it up. When I have more time, I'll be switching it to beast mode


----------



## bequietjk

I'd like to see Emotiva put out a headphone amp to rival and/or exceed the AAA 789.  That's what I'm waiting for.


----------



## Baten

bequietjk said:


> I'd like to see Emotiva put out a headphone amp to rival and/or exceed the AAA 789.  That's what I'm waiting for.


Well unless they use the licensed THX modules (tons of R&D put in their feed-forward distortion reduction mechanism) that seems doubtful but one can dream


----------



## allhifi

Yevgen Chupak said:


> but it's gonna be higher noise floor



Good point. I think. (lol) 

pj


----------



## greenkiwi

bequietjk said:


> I'd like to see Emotiva put out a headphone amp to rival and/or exceed the AAA 789.  That's what I'm waiting for.


I've heard that they have something in the works... though it's been in the works for a while.


----------



## bequietjk

I've been biting my nails since I heard of what may possibly be in the works.  Tis why I didn't place my order for the thx aaa 789.


----------



## Quigley28

Hello. I have been researching the a-100 for quite some time. I have a different use for the power and would love to hear if anyone has used it for the same. 

Myself and a few friends have the same headphones and like to listen all at the same time. As it stands I use two or three separate fiio A5 amps to run three hd6xx or some m50x at the same time using a splitter from a fiio M9 2volt output Dac. 

I want to simplify and have more power. 
Has anyone hooked up multiple headphones with a splitter off the headphone out, while having the jumpers installed for the additional power. 

I am curious if this would be An answer for us to have the exact same sound and volume from 2 or three different headphones (say hd650s) while also having a “more than needed” amount of volume without taking a hit to sound quality. 

Anyone try dual or triple listening off the A-100?

It seems like it would have loads of power for even 4-5 pairs of 300ohm headphones?

Thanks in advance for any input.


----------



## greenkiwi

I'd be going for multiple of the same amp. Or a few different amps so everyone can have their own volume controls


----------



## Quigley28

greenkiwi said:


> I'd be going for multiple of the same amp. Or a few different amps so everyone can have their own volume controls



Yes that is what we do now and it work ok. It’s just a wiring mess. We are on the same page for volume so one amp would suffice as we use the exact same pairs of headphone at a time. Also, when using three amps it take the volume down a bit from the dac. It would be nice to have one dac and one powerful amp for the multiple sets of identical headphones.


----------



## KeithEmo

With the jumpers installed, the A-100 would easily run as many as 50 or 75 pairs of 300 Ohm headphones, and each would play at the same volume (assuming the same model).
The Volume also will not change significantly regardless of how many pairs you plug in.
(No exaggeration there.... 75 pairs of 300 Ohm headphones in parallel is equivalent to a single pair of 4 Ohm speakers. .)

All you would need would be a passive splitter.
(You could wire up a nice panel with a whole bunch of headphone jacks in parallel... just be make sure to use non-shorting jacks.)

The A-100 could also run several pairs of high-impedance headphones with the jumpers out.
However, if you do that, the level will be slightly lower when multiple pairs are plugged in.




Quigley28 said:


> Hello. I have been researching the a-100 for quite some time. I have a different use for the power and would love to hear if anyone has used it for the same.
> 
> Myself and a few friends have the same headphones and like to listen all at the same time. As it stands I use two or three separate fiio A5 amps to run three hd6xx or some m50x at the same time using a splitter from a fiio M9 2volt output Dac.
> 
> ...


----------



## Quigley28

KeithEmo said:


> With the jumpers installed, the A-100 would easily run as many as 50 or 75 pairs of 300 Ohm headphones, and each would play at the same volume (assuming the same model).
> The Volume also will not change significantly regardless of how many pairs you plug in.
> (No exaggeration there.... 75 pairs of 300 Ohm headphones in parallel is equivalent to a single pair of 4 Ohm speakers. .)
> 
> ...




Thanks for the answer. It sounds like that will be my next logical  “headphone station”. Now I just have to hardwire my listening positions. Lol.


----------



## Quigley28

Quigley28 said:


> Thanks for the answer. It sounds like that will be my next logical  “headphone station”. Now I just have to hardwire my listening positions. Lol.




One more quick question if you will. 

In general, are the generic headphone splitters such as the amazon basics one non-shorted or is their a particular way to determine if they are or not with an ohmeter?


----------



## KeithEmo

Anything that calls itself a "headphone splitter" will be fine and won't use shorting connectors.
The Amazon Basics one looks fine.
I've used other Amazon Basics cables and such and always found them to very good quality.
Shorting connectors are sort of special - and would never be used in a device like that.
However, if you were to purchase a bunch of separate jacks, in order to build your own, you want to make sure and get the right ones.

It's also a good idea to plug and unplug your headphones while the amp is off.
Or, alternately, plug all the headphones into the splitter, then plug the splitter into the amp.
Some plugs will short for a split second as the plug is inserted.
This really shouldn't bother the A-100... but might cause it to go into protect... so better safe than sorry.



Quigley28 said:


> One more quick question if you will.
> 
> In general, are the generic headphone splitters such as the amazon basics one non-shorted or is their a particular way to determine if they are or not with an ohmeter?


----------



## lemarsghast

should I get the a100 and a dac over a nfb 11.28?


----------



## PopZeus

I think the amp on the NFB-11 is better than the A100 unless you need to drive insanely power-hungry headphones. The A100 head amp section tends to overtake the sound of regular headphones. I think it has to do with the very high output impedance.


----------



## Mightygrey

PopZeus said:


> I think the amp on the NFB-11 is better than the A100 unless you need to drive insanely power-hungry headphones. The A100 head amp section tends to overtake the sound of regular headphones. I think it has to do with the very high output impedance.


My advice as well. The high output-Z in regular-mode tended to wreak havoc with the frequency control of some of my cans (esp. the bass on my DT1770's, which became fart-y and flabby).


----------



## sanvara (Jul 23, 2019)

PopZeus said:


> I think the amp on the NFB-11 is better than the A100 unless you need to drive insanely power-hungry headphones. The A100 head amp section tends to overtake the sound of regular headphones. I think it has to do with the very high output impedance.



 I'm really liking the A100 with HD650s and HE560s. A bargain for the price.


----------



## Baten

Mightygrey said:


> My advice as well. The high output-Z in regular-mode tended to wreak havoc with the frequency control of some of my cans (esp. the bass on my DT1770's, which became fart-y and flabby).


Just use direct drive then


----------



## lemarsghast

PopZeus said:


> I think the amp on the NFB-11 is better than the A100 unless you need to drive insanely power-hungry headphones. The A100 head amp section tends to overtake the sound of regular headphones. I think it has to do with the very high output impedance.



As for my case, I have modded t50rps and a 600 ohm dt 880. Is the nfb11.28 sufficient for both, or is the a100’s direct drive still the best?


----------



## garbulky

lemarsghast said:


> should I get the a100 and a dac over a nfb 11.28?


I'm not entirely sure the impedance on your headphones - if you only have high impedance headphones or planar headphones then I would pick the A-100 and a dac with a volume control. I use my A-100 with a power amp. But if you have a mixture of headphones you may want to look for an amp that does well with both low and high impedance headphones.


----------



## gwertheim

Just a quick update, I added a set of kef q100's to the amp and they sound superb. No issues expect for distortion at above comfortable hearing levels. 

I have them sitting on a set of Isoacoustics stands and they are at the perfect height.

For anyone whose wondering if the a-100 can power speakers for a near field setup, this amp won't even break a sweat


----------



## nahpungnome

So I bought an A100 locally used last month and the only reason I bought it was because I purchased Hifman HE6se a couple of days before that.  I already had a Jot and I was able to max it out on low gain with the headphones.  I kept hearing good things about the A100 so I went ahead and got one.  I didn't even both leaving the headphone out in "normal" mode and installed the jumpers right away.

The headphone out with jumpers in is great with my HE6, Auteur, and even my Elears.  Although with the Elears I have to be more careful about the volume.  I got tired of using a XLR to 1/4" adapter so I made a XLR to banana plug to go directly to the speaker connections.  I then removed the jumpers so I could hear how they sound in normal mode.

The taps and front with the jumpers in sound the same to me, that is, clean and powerful.  I have to use the same amount of caution with the knob.

I then tried the headphone out in normal mode. The Auteurs actually sounded pretty decent and seemed to get just as loud as through the taps and jumper mode.  The Elears sounded pretty bad though.  The thing I noticed immediately was the bass..pretty bad, but I kind of expected that.  My HE6, well, I could max out the volume pot and it still didn't get loud enough, but again, I kind of expected that.

I was contemplating selling my Jot, but I found it useful for higher sensitivity cans like my Elears so it'll be staying around.


----------



## Baten

nahpungnome said:


> So I bought an A100 locally used last month and the only reason I bought it was because I purchased Hifman HE6se a couple of days before that.  I already had a Jot and I was able to max it out on low gain with the headphones.  I kept hearing good things about the A100 so I went ahead and got one.  I didn't even both leaving the headphone out in "normal" mode and installed the jumpers right away.
> 
> The headphone out with jumpers in is great with my HE6, Auteur, and even my Elears.  Although with the Elears I have to be more careful about the volume.  I got tired of using a XLR to 1/4" adapter so I made a XLR to banana plug to go directly to the speaker connections.  I then removed the jumpers so I could hear how they sound in normal mode.
> 
> ...


Yeah with lower impedance like Focals you don't want to have a high impedance resistor output like on the A-100 without jumpers.


----------



## nahpungnome

Baten said:


> Yeah with lower impedance like Focals you don't want to have a high impedance resistor output like on the A-100 without jumpers.



Yeah I just took them out since I wouldn't really be using the 1/4" jack anymore.  Glad I didn't jump the gun and sell my Jot after I got my A100...although A100 alone would've been fine too, would just have to be careful with the knob


----------



## Seancs14

Anyone have experience with using the A-100 and Focal Elex? My new office is isolated enough for me to have some speakers and I’d like to just have one amp to handle both some bookshelves and headphones. My Elex are the main headphones I use at work. Seems like I’ll have some hiss with jumpers in, but not sure what the effect will be of the low impedence without the jumpers in. 

For some context, my current headphone amp is a Schiit Jotunheim.


----------



## tim0chan

Seancs14 said:


> Anyone have experience with using the A-100 and Focal Elex? My new office is isolated enough for me to have some speakers and I’d like to just have one amp to handle both some bookshelves and headphones. My Elex are the main headphones I use at work. Seems like I’ll have some hiss with jumpers in, but not sure what the effect will be of the low impedence without the jumpers in.
> 
> For some context, my current headphone amp is a Schiit Jotunheim.


Way too much power, something like the PS audio sprout would do better, or use your jotunheim with a mini power amp like the Burson bang


----------



## nahpungnome (Jan 21, 2020)

Seancs14 said:


> Anyone have experience with using the A-100 and Focal Elex? My new office is isolated enough for me to have some speakers and I’d like to just have one amp to handle both some bookshelves and headphones. My Elex are the main headphones I use at work. Seems like I’ll have some hiss with jumpers in, but not sure what the effect will be of the low impedence without the jumpers in.
> 
> For some context, my current headphone amp is a Schiit Jotunheim.


I have the Elear and an A100.  The volume is very loud right when the left and right channels balance out on the volume pot.  It's about at the upper limit of what I normally listen to.  Maybe slightly higher.  I also have the Jot and I find the Jot and Elear go well together given the Elear's warm sound.

Btw that's with the full power mode.  With the regular mode, it sounded like junk.  Definitely not a good match for low impedance cans.  Sounds great with my Auteur though.


----------



## Seancs14

That’s helpful. Thanks for the insight and recommendations. 



tim0chan said:


> Way too much power, something like the PS audio sprout would do better, or use your jotunheim with a mini power amp like the Burson bang


----------



## Seancs14

Great, thanks for the insight on this. This was my worry with it. 



nahpungnome said:


> I have the Elear and an A100.  The volume is very loud right when the left and right channels balance out on the volume pot.  It's about at the upper limit of what I normally listen to.  Maybe slightly higher.  I also have the Jot and I find the Jot and Elear go well together given the Elear's warm sound.
> 
> Btw that's with the full power mode.  With the regular mode, it sounded like junk.  Definitely not a good match for low impedance cans.  Sounds great with my Auteur though.


H


----------



## KCXT

I grabbed one of these a couple of months back as a speaker/headphone amp combo that offers enough power to drive whatever headphones I may get my hands on. It's honestly exceeded my expectations with both my speakers (currently running JBL Studio 530s) and headphones. Even without the jumpers it added some more bass oomph and presence to my ATH-A900Xs which per the spec sheet don't seem too hard to drive (42 ohms, 100 db/mW), so perhaps the common bass-region impedance spike is higher than usual. Also does a great job pushing the DT 990s (250 ohm) and 1990s.

I'll also note that I've started it on my desk with some typical sources of EMI nearby and no appreciable noise is present. Wasn't a big concern but stranger things have happened.


----------



## ckhirnigs113

Anyone used their A100 with any of the ZMF dynamics? I have the ZMF Aeolus on the way to me and am eager to try it out with my A100. I have the jumpers installed currently for use with my Mod House Argons. I’m really interested to know if anyone has tried the Aeolus or any other ZMF dynamics with the A100 and whether they found them better with or without the jumpers installed.


----------



## Mightygrey

ckhirnigs113 said:


> Anyone used their A100 with any of the ZMF dynamics? I have the ZMF Aeolus on the way to me and am eager to try it out with my A100. I have the jumpers installed currently for use with my Mod House Argons. I’m really interested to know if anyone has tried the Aeolus or any other ZMF dynamics with the A100 and whether they found them better with or without the jumpers installed.


It's better without the jumpers, I've used the Eikon with the A-100 whose high output impedance plays nicely the.


----------



## ckhirnigs113

@Mightygrey Thanks for the feedback. I was thinking the high output impedance might be the ticket with the 300ohm Aeolus. Lots of guys on the ZMF threads are using OTL tube amps with high output impedance, but I don’t have a tube amp so jumpers out on my A100 is as close as I can get at the moment. Thanks again.


----------



## SilverEars (Dec 4, 2020)

What a great value of an amp!  I think this amp performs way above it's price.  What can you get with this price, Schiit Magnius?  This amp probably performs on the level of Schiit Rag, which I didn't think had that good of a performance (it was alright).  Definately better than all Schiit products under Rag.

It was recommended by somebody to try out the DT800 and that person was right, it did add better bass, and transients are very fast and very snappy amp.  Then I decided to try the HD800S, and I can recommend for HD800S.  It's one of the rare few solid-states I've experience to work well with HD800S.  Dynamics on this amp really good.  I think it is better than Rag in driving the HD800S.  Rag sucks at driving it.

I find it interesting that these amps are actually assembled in the USA, and priced lower that some Chinese amps.

If you are going to have one amp to drive many headphones including the HE6, this is it.


----------



## justhavingfun

If you guys have Beyerdynamic DT-770 600 ohms version, this amp will make this headphone come alive. My pair was mainly collecting dust in the closet for many years due to it sounds anemic with many of other amps that I have tried. Computer desktop streaming Tidal > Emotiva DC-1 > BasX100 (with jumper placed) > DT-770 600 ohms. Both-600 ohms, DT-770 and DT-880 sound fantastic with this amp.


----------



## bigjako

I’m hoping some Basx A100 owners or reps can help guide me with a problem I’m having.  It’s a unique case.. I’m using the A100 to power my Jecklin PS2 Electrostatic Energizer (the equivalent of a Stax SRD-7). I’d previously used a little Kinter Tripath amp that worked well, but upgraded to the A100.  When connected to the PS2 I get audio but whenever I turn the volume up loud (about 12 o clock, which doesn’t really have much volume, I’d say just loud but listening levels), it goes into blinking-amber fault mode.  Originally I was using bare ended speaker wire so thought it could be a short in the speaker cables, as per the manual.  So I swapped over to brand new banana terminated cables and still have the issue.  

I’ve checked the A100 and PS2 fuses and they’re all good. The 4.4 terminal jack produces good sound at loud volumes, so I think it’s entirely to do with how the A100 plays with the electrostatic energizer (about 800-900 cola, if I recall correctly, not 580 like Stax).

Two main questions:
1. If not a speaker cable short, any other ideas what may be kicking it into fault mode? At higher volume only?
2. Could using the jumpers help in any way, by giving the amp more power to handle the energizer?

Any other thoughts are appreciated, and there’s no Jecklin thread I can post this to, so you’re my best hope.  My fear is that a cap is blown somewhere in the chain, but if so, I’m not sure why would it work at low volumes but fault at high.


----------



## ckhirnigs113

bigjako said:


> I’m hoping some Basx A100 owners or reps can help guide me with a problem I’m having.  It’s a unique case.. I’m using the A100 to power my Jecklin PS2 Electrostatic Energizer (the equivalent of a Stax SRD-7). I’d previously used a little Kinter Tripath amp that worked well, but upgraded to the A100.  When connected to the PS2 I get audio but whenever I turn the volume up loud (about 12 o clock, which doesn’t really have much volume, I’d say just loud but listening levels), it goes into blinking-amber fault mode.  Originally I was using bare ended speaker wire so thought it could be a short in the speaker cables, as per the manual.  So I swapped over to brand new banana terminated cables and still have the issue.
> 
> I’ve checked the A100 and PS2 fuses and they’re all good. The 4.4 terminal jack produces good sound at loud volumes, so I think it’s entirely to do with how the A100 plays with the electrostatic energizer (about 800-900 cola, if I recall correctly, not 580 like Stax).
> 
> ...


I can't help too much, but I can say the jumpers only affect the headphone out. They don't have any effect on the speaker output.


----------



## bequietjk

Is the voltage swing displayed in the manual or anywhere else accessible to consumers?


----------



## gikigill

I have lost the jumpers on my A-100. Can anyone suggest a replacement.


----------



## amoeba1126

I got an A-100 recently and was wondering if the headphone jack was safe to use for my TH-X00 or do I have to worry about it melting it?


----------



## ckhirnigs113

It should be safe as long as you’re extremely careful with the volume knob. I put a little white sticker on mine to be able to easily see the volume position. I always turn it all the way down before playing anything through it and turn it up very slowly.


----------



## KCXT

gikigill said:


> I have lost the jumpers on my A-100. Can anyone suggest a replacement.


Have you contacted Emotiva? That is likely your best bet.


----------



## ckhirnigs113

gikigill said:


> I have lost the jumpers on my A-100. Can anyone suggest a replacement.


Just search “computer jumpers” on Amazon and you can get a pack of 100 for $6. That’s all they are, nothing specific to Emotiva.


----------



## justhavingfun

gikigill said:


> I have lost the jumpers on my A-100. Can anyone suggest a replacement.


Those jumpers are very common kind that you find in the computer motherboard. Any decent computer parts store should have them. You can even order through Amazon.
https://www.amazon.com/2-54mm-Stand...ywords=computer+jumpers&qid=1616730979&sr=8-3


----------



## gikigill

Cheers everyone, found a bag from a local shop.


----------



## Jimmyblues1959

Just checked on the Emotiva Website and they have the A100 BASX on closeout for $199.  I wonder what they are going to replace it with?  In terms of sheer power it is the headphone bargain amp of the past decade.


----------



## Mightygrey

Jimmyblues1959 said:


> Just checked on the Emotiva Website and they have the A100 BASX on closeout for $199.  I wonder what they are going to replace it with?  In terms of sheer power it is the headphone bargain amp of the past decade.


A few features I'd love to see on a new version:

- A remote
- One more analogue input
- Pre-out
- Switchable jumpers (so you don't need to disassemble every time you want to go into 'nuclear mode')


----------



## Jimmyblues1959

Mightygrey said:


> A few features I'd love to see on a new version:
> 
> - A remote
> - One more analogue input
> ...



These features would be nice.  I have not heard anything mentioned in regard to a replacement for the BASX A100 though..


----------



## bequietjk

This is exciting news!

New headphone amp from Emotiva?

HELLLLL YEAHHHHH


----------



## Namtar

bequietjk said:


> This is exciting news!
> 
> New headphone amp from Emotiva?
> 
> HELLLLL YEAHHHHH



where did you see this news?  I know there was one rumored a couple years ago


----------



## Baten

bequietjk said:


> This is exciting news!
> 
> New headphone amp from Emotiva?
> 
> HELLLLL YEAHHHHH


Yeah, source?


----------



## lambdastorm

Namtar said:


> where did you see this news?  I know there was one rumored a couple years ago


iirc it's more than a rumor but less than an actual product. They posted the idea and roadmap of the amp but it never gets beyond that.


----------



## Jimmyblues1959

lambdastorm said:


> iirc it's more than a rumor but less than an actual product. They posted the idea and roadmap of the amp but it never gets beyond that.



Now that it appears that the BASX A 100 is being discontinued, perhaps the headphone amp mentioned by an Emotiva employee
in this thread a few years ago will become a reality.  Tempted to pull the trigger at the $199 price for the A 100.


----------



## SilverEars

Jimmyblues1959 said:


> Now that it appears that the BASX A 100 is being discontinued, perhaps the headphone amp mentioned by an Emotiva employee
> in this thread a few years ago will become a reality.  Tempted to pull the trigger at the $199 price for the A 100.


If you like HIfiman planars, it's worthwhile to have around.


----------



## Jimmyblues1959

SilverEars said:


> If you like HIfiman planars, it's worthwhile to have around.



Thanks for the input! 😊


----------



## Jimmyblues1959 (May 31, 2021)

Ckhirnigs113,  noticed you have a BASX A100 and a Shortest Way 51+.  Would be very interested in hearing your impressions of both.


----------



## Baten

Jimmyblues1959 said:


> Ckhirnigs113,  noticed you have a BASX A100 and a Shortest Way 51+.  Would be very interested in hearing your impressions of both.


serious question, don't you have enough amps already? haha.


----------



## Jimmyblues1959 (Jun 1, 2021)

Baten said:


> serious question, don't you have enough amps already? haha.



Yep.. LoL. And I just added a BASX A100 at $199 - one of the better bargains out there.  😁 A few hours after I placed an order on the Emotiva website I noticed that when you try to order an A 100 now, the status has changed to temporarily unavailable. I did take a look at the Emotiva Lounge and a very recent poster did confirm that the A 100 has been discontinued.

  So I guess the company is just selling off whatever A100s they have left. I have an invoice for one, however, I
wonder if they are oversold now and won't be able to deliver on some of the amps they have sold?

Got an updated Email from Emotiva saying that my A 100 shipped and should be delivered by Thursday!

What a great run this headphone amplifier has had over the last few years!


----------



## Draygonn

I hope my A-100 lasts forever.  One of my favorite audio purchases.


----------



## IBJamon

I absolutely love my A-100.  It's a fantastic desktop amplifier, and a great headphone amp - if you have inefficient headphones.  I do wish it had an option for a voltage divider/reduced power out (with low impedance) instead of the goofy 220 Ohm resistor, however.  I imagine it might be possible to mod that in for the jumpers.... I really should just do that sometime.  (I instead made an external adapter)


----------



## ckhirnigs113

Jimmyblues1959 said:


> Ckhirnigs113,  noticed you have a BASX A100 and a Shortest Way 51+.  Would be very interested in hearing your impressions of both.


I used to use Mod House Argons as my main headphones and really liked the A100 with them. Now that I’ve made the jump to the Verite Closed, I don’t use the A100 much anymore with headphones.

I haven’t done a head to head comparison between the A100 and SW51+, but I can say I wasn’t a fan of how the A100 sounded with my ZMF’s with or without jumpers installed. I actually preferred my JDS Labs EL Amp II with the VC when I compared them before getting any tube amps.

In general, the SW51+ and my Quicksilver Headphone Amp, sound more 3D and nuanced vs my solid state amps, the EL and A100. I prefer the tube amps pretty handily with my VC. The Argon/A100 combo is still a great pairing. I always had the jumpers installed with that setup.

I know this isn’t terribly helpful, but I suppose what I’m saying is that it really depends on what headphones you’ll be pairing the amps with. In general, the A100 is a great deal at its price point and still gets my recommendation for those needing a solid headphone/speaker amp, especially those that have hard to drive planars.


----------



## califmike33

I have had this amp for 2 weeks now and its ok.  I dont like the headphone amp part, its lacking detail and the bass is blotted.  As far as for speakers go it rocks as a desktop amp for speakers, but i dont care for the headphone amp.  I tried my Sennhiser Hd 560s and they sound ok, but not great.  I bought it for the headphone and speaker part, now im down to just using it for just speaker amp.  Im thinking of sending it back for a refund, as its a weird size very narrow but very deep.  Anybody want to shoot me a offer im interested.


----------



## Jimmyblues1959 (Jun 2, 2021)

ckhirnigs113 said:


> I used to use Mod House Argons as my main headphones and really liked the A100 with them. Now that I’ve made the jump to the Verite Closed, I don’t use the A100 much anymore with headphones.
> 
> I haven’t done a head to head comparison between the A100 and SW51+, but I can say I wasn’t a fan of how the A100 sounded with my ZMF’s with or without jumpers installed. I actually preferred my JDS Labs EL Amp II with the VC when I compared them before getting any tube amps.
> 
> ...



Thanks for the helpful reply!  I just purchased an A 100 to drive my planar magnetics.  Should be getting the A100 on Thursday,
and will leave some impressions after listening for a bit.  I have both tube headphone amps and solid state.  Also hybrids. They all
have their purpose and I have found proper impedance matching between headphones and headphone amps to be of paramount
importance in getting the best performance out of them.

Did not realize you had a Quicksilver headphone amp.  That's a neat piece of gear and based on my experience with the company
(once owned a pair of 8417 mono blocks and continue to own a pair of Mini Mite Monos purchased new in 2006) probably sounds terrific (especially with higher impedance headphones).  Mike Sanders builds excellent components at a very reasonable price and he's great to deal with.

Thanks again for your input on the A 100! 😊


----------



## IBJamon

califmike33 said:


> I have had this amp for 2 weeks now and its ok.  I dont like the headphone amp part, its lacking detail and the bass is blotted.  As far as for speakers go it rocks as a desktop amp for speakers, but i dont care for the headphone amp.  I tried my Sennhiser Hd 560s and they sound ok, but not great.  I bought it for the headphone and speaker part, now im down to just using it for just speaker amp.  Im thinking of sending it back for a refund, as its a weird size very narrow but very deep.  Anybody want to shoot me a offer im interested.


Try listening to it in bypass mode before sending it back.  Your opinion of the sound is consistent with an impedance mismatch - if your headphones have a lower impedance than the amp's output impedance (in this case the headphone out is 220 Ohm by default!).  They designed this amp's default sound profile to 'mirror the classic receivers of the 70s' according to the creators, which was not the best decision IMO.  Bypass mode instead gives you incredible grunt - though there may be noise if your headphone is too efficient.

What I did was to create a voltage divider adapter, that I use for more efficient headphones, which I then bypass for my planars.  I talked about this many pages back, here:
https://www.head-fi.org/threads/emotiva-a-100.825970/post-14057326

Best of luck!


----------



## califmike33 (Jun 2, 2021)

Okay because I'm using the Sennheiser 560s which is only 120 ohm, so I'm guessing if I put the Jumpers in it's going to barbecue my headphones they don't need that much power.  So I don't think this amp is going to benefit me by putting the Jumpers in with my sennheisers I need like a 300 ohm or higher headphone.  I mean they don't sound terrible they just don't have any resolution I don't know it just don't like the sound of them in this amp.  I might try what you said hooking up to cut the power down and see what it does I read a review on this from Josh valer I think did a review on this he didn't like the sound of his headphone amp either he said the speaker part of it's fantastic which I have to agree he didn't care for the headphone part.

When you say they made this to mimic a 70s vintage amp is that just a headphone part or is that the overall sound signature of the entire amp including speakers?


----------



## Draygonn

califmike33 said:


> When you say they made this to mimic a 70s vintage amp is that just a headphone part or is that the overall sound signature of the entire amp including speakers?


That's just the headphone part without the jumpers.  It doesn't affect the speakers, or the jumpers-connected full power headphone output.


Keith (_Emotiva Supremus_) explains how it works on an Emotiva forum thread:


> Vintage equipment, up through the 1960's or 1970's, virtually always derived the headphone outputs from the main outputs - through dropping resistors in the 100 - 250 Ohm range.
> This offers very little damping to the headphones, and can also result in a significant variation in frequency response due to the interaction between that output impedance and the impedance of the headphones.
> Because of this interaction the actual frequency response, and the variation from flat, will depend on the impedance curve of the particular headphones you connect.
> 
> ...


----------



## Jimmyblues1959 (Jun 4, 2021)

Jimmyblues1959 said:


> Thanks for the helpful reply!  I just purchased an A 100 to drive my planar magnetics.  Should be getting the A100 on Thursday,
> and will leave some impressions after listening for a bit.  I have both tube headphone amps and solid state.  Also hybrids. They all
> have their purpose and I have found proper impedance matching between headphones and headphone amps to be of paramount
> importance in getting the best performance out of them.
> ...





Jimmyblues1959 said:


> Thanks for the helpful reply!  I just purchased an A 100 to drive my planar magnetics.  Should be getting the A100 on Thursday,
> and will leave some impressions after listening for a bit.  I have both tube headphone amps and solid state.  Also hybrids. They all
> have their purpose and I have found proper impedance matching between headphones and headphone amps to be of paramount
> importance in getting the best performance out of them.
> ...



Received my Emotiva BASX A100 yesterday.   Impressive piece of gear.  Especially for the price. Emotiva
does a really nice job with the packaging.  A nice extra was the cloth bag to store this amp in, emblazoned with the
Emotiva logo.

After a brief listen in standard non jumper mode,  I really like the sound of the A100.  Very clean.  And it's very quiet with
my IEM's!   Still breaking it in. I will comment further after I have heard it with my high impedance dynamic and planar magnetic
headphones; in both jumper and non jumper mode.

I can understand why the A100 is so popular.  It offers tremendous value for your audio dollar.


----------



## Baten

Quiet with IEMs? What sorcery is that  mine had fairly high/audible noise floor!


----------



## Jimmyblues1959 (Jun 19, 2021)

Baten said:


> Quiet with IEMs? What sorcery is that  mine had fairly high/audible noise floor!



I was pleasantly surprised.  The setup I am using  for the summer months is an Amazon Fire HD 10 v. 7 to a Schiit Modius feeding a JDS Labs Atom or Emotiva BASX A100, to a BASN B Master Triple or Linsoul KZ  ZST X.

Also noticed how cool the BASX A100 runs.  Very pleased with the A 100 thus far.  Looking forward to trying it with the jumpers and
my higher impedance and planar magnetic headphones in the fall...

Update: Spoke with Emotiva today and the A100 is definitely discontinued.  They don't have a replacement yet, but the A100 is going to be a tough act to follow.  I do remember a member of Emotiva (who is also a member of Head-Fi) mentioning a new Emotiva balanced headphone amplifier that was in the pipeline. 

However, this was a few years ago and nothing further was ever mentioned about it.


----------



## KCXT

califmike33 said:


> I have had this amp for 2 weeks now and its ok.  I dont like the headphone amp part, its lacking detail and the bass is blotted.  As far as for speakers go it rocks as a desktop amp for speakers, but i dont care for the headphone amp.  I tried my Sennhiser Hd 560s and they sound ok, but not great.  I bought it for the headphone and speaker part, now im down to just using it for just speaker amp.  Im thinking of sending it back for a refund, as its a weird size very narrow but very deep.  Anybody want to shoot me a offer im interested.


This is about where I've ended up with mine as well. I loved it with my DT-1990s (no longer own them), which are 250 ohm and benefitted from a 'rounding' of the sound IMO, but I haven't really liked it with anything else. It pushes my HE6se V2s a touch better than the THX 789 in the bass frequencies but loses some of that precise magic elsewhere in the spectrum. Not generally a worthy trade-off for me.

For speakers though yeah, it makes my desktop Revels sing and I'm happy to own it. Just not in the headphone rotation anymore.


----------



## garbulky (Jun 8, 2021)

califmike33 said:


> Okay because I'm using the Sennheiser 560s which is only 120 ohm, so I'm guessing if I put the Jumpers in it's going to barbecue my headphones they don't need that much power.  So I don't think this amp is going to benefit me by putting the Jumpers in with my sennheisers I need like a 300 ohm or higher headphone.  I mean they don't sound terrible they just don't have any resolution I don't know it just don't like the sound of them in this amp.  I might try what you said hooking up to cut the power down and see what it does I read a review on this from Josh valer I think did a review on this he didn't like the sound of his headphone amp either he said the speaker part of it's fantastic which I have to agree he didn't care for the headphone part.
> 
> When you say they made this to mimic a 70s vintage amp is that just a headphone part or is that the overall sound signature of the entire amp including speakers?


Hi no you won't barbecue your headphones. I use it with my HD700's which are 150 ohm impedance with the jumpers. I've also used it with headphones that have less impedance. However, you know make sure you have it at minimum volume and increase from there (common sense). Without the jumpers the output impedance for the amp is 220 ohms (which are higher than your HD560's 120 ohms) which can cause frequency variations. So you should try it in direct drive to see what you think of it. The worse you'll find is that there might be a noticeable hiss or you may find you have too little play on the volume knob before it's too loud.


----------



## KCXT (Jun 10, 2021)

Got a pair of Dan Clark Audio Aeon Flow Closed RTs (that's a lot of typing...) today and even with its very low impedance I'm surprised at how well it pairs with the A-100. The DT-1990s are the only other headphones I've owned that sounded good, let alone better, with the A-100 but I'll be damned if these AFC RTs don't love it. They were fine, if unremarkable, with the THX 789 but really woke up with the A-100. Have more evaluation to do overall but this is a great pairing.


----------



## Jimmyblues1959 (Jul 1, 2021)

xXxDanXx said:


> Do you have any thoughts on a DIY bulk cables? I've been considering picking some bulk cable from DH Labs to get a better arrangement of my equipment from the power source to the unit. The BasX power cable is quite short. Considering this one at $8/ft: http://silversonic.com/products/bulk-wire-and-cable/bulk-power-cable/power-ac-power-cable/ would be a reasonable price. I haven't made a power cable before but I'd imagine it would be quicker than making custom PSU cables for a HTPC case or on par with networking cables. The connectors though can get quite pricey.
> 
> 
> 
> ...




In my experience,  the Asgard 2 did not sound great with the HD600 or the HD6XX.  However,  it sounds great with my Fostex T50RP MK 3 and Hifiman HE 4XX.  This makes sense since the A2 makes a full watt of power between 32 and 50 ohms. 

The BASX A100 sounds great in normal mode with everything from IEMs and planars to dynamic headphones.  The benefits of the high power setting are in regard to very inefficient headphones.  The BASX is arguably the best value in headphone amplifiers to come along in the past 20 years.  And the fact that it is also a very good speaker amplifier is an added bonus.


----------



## Jimmyblues1959 (Jul 1, 2021)

xXxDanXx said:


> Do you have any thoughts on a DIY bulk cables? I've been considering picking some bulk cable from DH Labs to get a better arrangement of my equipment from the power source to the unit. The BasX power cable is quite short. Considering this one at $8/ft: http://silversonic.com/products/bulk-wire-and-cable/bulk-power-cable/power-ac-power-cable/ would be a reasonable price. I haven't made a power cable before but I'd imagine it would be quicker than making custom PSU cables for a HTPC case or on par with networking cables. The connectors though can get quite pricey.
> 
> 
> 
> ...




Double post


----------



## garbulky

KCXT said:


> Got a pair of Dan Clark Audio Aeon Flow Closed RTs (that's a lot of typing...) today and even with its very low impedance I'm surprised at how well it pairs with the A-100. The DT-1990s are the only other headphones I've owned that sounded good, let alone better, with the A-100 but I'll be damned if these AFC RTs don't love it. They were fine, if unremarkable, with the THX 789 but really woke up with the A-100. Have more evaluation to do overall but this is a great pairing.


I'm probably going to order the Ether 2 flow headphones to see how well it works.


----------



## SilverEars (Jul 3, 2021)

Jimmyblues1959 said:


> In my experience,  the Asgard 2 did not sound great with the HD600 or the HD6XX.  However,  it sounds great with my Fostex T50RP MK 3 and Hifiman HE 4XX.  This makes sense since the A2 makes a full watt of power between 32 and 50 ohms.
> 
> The BASX A100 sounds great in normal mode with everything from IEMs and planars to dynamic headphones.  The benefits of the high power setting are in regard to very inefficient headphones.  The BASX is arguably the best value in headphone amplifiers to come along in the past 20 years.  And the fact that it is also a very good speaker amplifier is an added bonus.


I don't find the normal mode sounds as good as full-power mode.  Issue is that full-power mode's gain is just too much that it will be too loud to the point of causing hearing damage.

They should make one dedicated for headphones (with proper gain level) without the usage of passive circuity to reduced loudness.  That passive circuitry causes lower quality sound.


----------



## garbulky

SilverEars said:


> I don't find the normal mode sounds as good as full-power mode.  Issue is that full-power mode's gain is just too much that it will be too loud to the point of causing hearing damage.
> 
> They should make one dedicated for headphones (with proper gain level) without the usage of passive circuity to reduced loudness.  That passive circuitry causes lower quality sound.


I agree. The full power mode is spectacular as long as your headphones are at the right impedance where the noise isn't noticeable (and also allows you enough play on the volume). Headphones like the HD800S and HD600S do fine. But lower impedance headphones have issues. Emotiva was going to make a class A fully balanced headphone amp but it has been put on hold.


----------



## SilverEars

garbulky said:


> Emotiva was going to make a class A fully balanced headphone amp but it has been put on hold.


Emotiva proved they are very capable and don't rip off customers.


----------



## KCXT

garbulky said:


> I'm probably going to order the Ether 2 flow headphones to see how well it works.


Be prepared for the possibility of a bit of hiss in full-power mode, but it sure does sound great with actual music.


----------



## Jimmyblues1959

SilverEars said:


> I don't find the normal mode sounds as good as full-power mode.  Issue is that full-power mode's gain is just too much that it will be too loud to the point of causing hearing damage.
> 
> They should make one dedicated for headphones (with proper gain level) without the usage of passive circuity to reduced loudness.  That passive circuitry causes lower quality sound.



I have read that but have not used the higher power more long enough 


SilverEars said:


> I don't find the normal mode sounds as good as full-power mode.  Issue is that full-power mode's gain is just too much that it will be too loud to the point of causing hearing damage.
> 
> They should make one dedicated for headphones (with proper gain level) without the usage of passive circuity to reduced loudness.  That passive circuitry causes lower quality sound.



It'll be interesting to see what Emotiva replaces the A 100 with.  They've had real good success with the  A 100 so they want
to make sure that whatever headphone amp follows it appeals to both Emotiva customers and potential new customers 
in the future.  Would not be at all surprised to see the company offer a dedicated headphone amp in the future. Perhaps even
a dac/amp combo.


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## Pashmeister

My secondary set up in the living room for my TC and susvara is a budget chain that uses all stuff that push past their price points. 

BasX a100 is the cheapest headphone  amp that I could use to power these cans. With an ifi itube2 it refines and improves the sound significantly. A raspberry Pi4 streamer cleans up the signal further. HQplayer NaA for 786Khz upsampling with SMsL SU9. Top tier TC/Susvara chain for not a lot of cash.


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## iFi audio

Pashmeister said:


> BasX a100 is the cheapest headphone amp that I could use to power these cans. With an ifi itube2 it refines and improves the sound significantly. A raspberry Pi4 streamer cleans up the signal further. HQplayer NaA for 786Khz upsampling with SMsL SU9. Top tier TC/Susvara chain for not a lot of cash.



Smart-fi at its finest 

I gather from this that iTube2 works in that setup as a buffer?


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## Pashmeister

iFi audio said:


> Smart-fi at its finest
> 
> I gather from this that iTube2 works in that setup as a buffer?


As a buffer, yes


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## IBJamon

I reconnected my A-100 as a headphone amp to connect to my Koss ESP's - I honestly can't tell you why they sound so much better after being ran through the A-100s - but they do.  It's so good to have it back; I went without my A-100 for a while after moving for a while.  Can't explain the happy ears, but I'll take it!


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## sanvara (Nov 10, 2021)

_BasX a100 is the cheapest headphone  amp that I could use to power these cans. With an ifi itube2 it refines and improves the sound significantly. *A raspberry Pi4 streamer cleans up the signal further*._

Just curious how the Pi cleans up the signal?


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## Pashmeister

sanvara said:


> _BasX a100 is the cheapest headphone  amp that I could use to power these cans. With an ifi itube2 it refines and improves the sound significantly. *A raspberry Pi4 streamer cleans up the signal further*._
> 
> Just curious how the Pi cleans up the signal?


While a streamer is generally electrically cleaner compared to music from a laptop/pc, I should also clarify that my Pi4 has an Alo Digione Signature hat which allows me to connect to the DAC via spdif/bnc


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## iFi audio

Pashmeister said:


> While a streamer is generally electrically cleaner compared to music from a laptop/pc,



That's true, laptops/PCs are noisy primarily due to their multitasking and power suppies, these are the two major offenders. Streamers are in fact computers, but with a rather narrow specialization and they can be powered by silent PSUs. That's what makes the difference.


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## abccpu

When speakers are connected and headphones are plug in then speakers have cut off sound ? I'm sorry if there was that question in past.


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## Jimmyblues1959

abccpu said:


> When speakers are connected and headphones are plug in then speakers have cut off sound ? I'm sorry if there was that question in past.



I believe that the speakers and headphones operate simultaneously.


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## Draygonn

abccpu said:


> When speakers are connected and headphones are plug in then speakers have cut off sound ? I'm sorry if there was that question in past.


When the headphones are connected the speakers are automatically shut off.


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## abccpu

Draygonn said:


> When the headphones are connected the speakers are automatically shut off.


Thanks ! That I was expecting because I plan to use mainly with headphones but PC passive speakers will be connected too.


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## Jimmyblues1959

abccpu said:


> Thanks ! That I was expecting because I plan to use mainly with headphones but PC passive speakers will be connected too.




I actually own an A-100 but have only used it as a headphone amp.  So I was not certain whether or not the headphone amp muted the speaker outputs.
Glad to get this information.  Happy Holidays to Draygonn and Abccpu!  😊


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## sludgeogre

I've had this amp since shortly after release, and I also own the original mini-x without the headphone output, and I finally used the A-100 in full power mode with my LCD-2. I had to order a pack of jumpers just to put 2 on the dang board, but I finally did it after all these years. I was using an Asgard-2 to power the LCD-2 before, but I didn't want that space heater on my desk anymore.

The sound is extremely engaging. Music sounds more dynamic through the A-100, as one would imagine with so much more power. The noise floor is insanely high as others have mentioned, so it really is the same experience as an old vintage speaker amp, but you can't hear any noise once something is going, even video games.

The only downside is that there is severe channel imbalance up until about 20% of tolerable volume. I'm going to try putting a SYS in between for some extra play on the volume pot, but it won't help the channel imbalance issue and I'm worried it'll make that crazy noise floor even higher.

Overall a good, fun experience.


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## Jimmyblues1959

sludgeogre said:


> I've had this amp since shortly after release, and I also own the original mini-x without the headphone output, and I finally used the A-100 in full power mode with my LCD-2. I had to order a pack of jumpers just to put 2 on the dang board, but I finally did it after all these years. I was using an Asgard-2 to power the LCD-2 before, but I didn't want that space heater on my desk anymore.
> 
> The sound is extremely engaging. Music sounds more dynamic through the A-100, as one would imagine with so much more power. The noise floor is insanely high as others have mentioned, so it really is the same experience as an old vintage speaker amp, but you can't hear any noise once something is going, even video games.
> 
> ...




IMHO the A-100 is one of the greatest bargains in audio gear that's  ever been offered.  No other headphone amp even  close to  this price 
offers the A-100's power.  I really like it with my planars,  but also to drive my Sennheiser HD6XX and HD600. Even better is how the 
the A-100 works with my old 600 ohm AKG K240 Sextetts.  It usually takes a good tube headphone amp (esp. Otl's) to make the 
Sextetts sound their best,  but the A-100 does surprisingly well.  And drives them effortlessly.  I just wish that Emotiva still made the A-100.


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## sludgeogre

Jimmyblues1959 said:


> IMHO the A-100 is one of the greatest bargains in audio gear that's  ever been offered.  No other headphone amp even  close to  this price
> offers the A-100's power.  I really like it with my planars,  but also to drive my Sennheiser HD6XX and HD600. Even better is how the
> the A-100 works with my old 600 ohm AKG K240 Sextetts.  It usually takes a good tube headphone amp (esp. Otl's) to make the
> Sextetts sound their best,  but the A-100 does surprisingly well.  And drives them effortlessly.  I just wish that Emotiva still made the A-100.



That is pretty cool. It makes sense that this amp would be a total dream with high impedance headphones and it almost makes me want to pick up a pair, but I've been so happy with my LCD-2's for years now I haven't had the urge to buy other headphones.

I look forward to seeing what Emotiva does next. I really liked the Mini-X, so much that I bought two, but the form factor is really weird and doesn't really fit well anywhere, plus all of their new designs are Class H. Would be interesting to see what kind of high power they can pack into a small form factor that fits better on a desk.


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## abccpu (Dec 2, 2021)

Is someone tried to replace reistors in direct drive mode for higher value to reduce power output ? Lowering power output will help with small adjustment of volume range pot.


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## Draygonn

I use attenuators to solve low volume channel imbalance.


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## abccpu

Sure but I can turn down volume on DAC without buying attenuators  I'm asking about resistors near 6.35mm output jack in Emotiva.


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## califmike33

Old thread I know can anybody tell me a good pair of bookshel speakers that pair well with this amp?


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## LHS

califmike33 said:


> Old thread I know can anybody tell me a good pair of bookshel speakers that pair well with this amp?



Budget? Any 4ohm speakers would work well with it depending on how loud you need to get.


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## abccpu

I have paired with DAC SMSL SU-9 and Sony SS-LA500ED. Amazing good small set for TV.


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## califmike33 (Feb 17, 2022)

Budget is going to be 500 and under I don't want floor standing got to be a bookshelf speaker.  I tend to like a little bit warmer of a sound just a touch of warmth.

I'm not trying to get crazy loud volume I've got a 12 ft x 12 ft room it's not huge looking to fill the room with some good sound.

The triangle Borea bro 2, is the first speaker that comes to mind but I'm wide open.


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## IBJamon

Honestly this amp can drive well pretty much any bookshelf.  Just choose what you like.    I'm pairing mine with a fairly cheap pair of Pioneer BS-22's and they sound great together.


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## iFi audio

califmike33 said:


> Budget is going to be 500 and under I don't want floor standing got to be a bookshelf speaker. I tend to like a little bit warmer of a sound just a touch of warmth.



If you're lucky, every now and then used KEF LS50 pop up at about $550-600. These are brilliant as bookshelf speakers.


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## HWB3

califmike33 said:


> Old thread I know can anybody tell me a good pair of bookshel speakers that pair well with this amp?


  I drive a pair of Elac UB5's with mine as well as using it as a headphone amp. They are 4 ohm speakers with 85 db sensitivity and the amp does a good job with them. I've seen them on Ebay for around $300 used. They sound great.


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## IBJamon

Did you guys see that they finally replaced this model?

https://emotiva.com/collections/frontpage/products/basx-a2m-stereo-flex-amplifier

I would say that since it uses a SMPS power supply instead of a linear, this one is likely to retain its value for quite some time


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## HWB3

IBJamon said:


> Did you guys see that they finally replaced this model?
> 
> https://emotiva.com/collections/frontpage/products/basx-a2m-stereo-flex-amplifier
> 
> I would say that since it uses a SMPS power supply instead of a linear, this one is likely to retain its value for quite some time


  I'd be anxious to see how well it sells. The amp has only one input and it goes for close to $300. I have both the MiniX and BassX. Love both of them but I paid a lot less for them.


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## IBJamon

HWB3 said:


> I'd be anxious to see how well it sells. The amp has only one input and it goes for close to $300. I have both the MiniX and BassX. Love both of them but I paid a lot less for them.


Very good point - I think I paid $229 for mine.  I don't know if my wife would have let me swing $300


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## Draygonn (Feb 21, 2022)

I'm guessing just a pandemic related price increase.  I'm glad they are keeping the line going, I love my A-100.


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## Anonymous12345

Hello everyone, I just want to ask a question: Has anyone tried the ATH R70X 470 ohms, 99db sensitivity with A100? Kinda overkill, but in my country, pretty sure I can find this cheaper than a Xduoo XD05 Bal, mojo, idsd micro BL and a cayin iha6. All of the amps I just mentioned is rumoured to pair great with the R70x. And also, is the headphone out of the a100 clean? Not expecting much seeing the 50watts output, but I have to try. 
Thank you everybody.


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## 0l3g

califmike33 said:


> The triangle Borea bro 2, is the first speaker that comes to mind but I'm wide open.


it's a long shot but have you finally got the Borea BRO-2's ? If yes, I'd be interested to hear you thoughts on how well they pair


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