# Audio GD SA-31  head amp/ preamp . A powerfull Head Amp with Diamond Difference design .



## HaVoC-28

Remember the Audio GD C2-SA ? Cheap and yet very powerfull . It's seams back , a bit pricer but even more powerfull . 
   
   
  http://www.audio-gd.com/Pro/SA/SA31/SA31EN.htm
   

   

   
   
  This beast should be able to drive any headphone 
	

	
	
		
		

		
			





 like Hifiman HE-6 etc . 
   
   
  SA-31 Standard (applied Neutrik RCA scokets): USD499
   
   
  and an optional remote control . More informations at audio GD ^^
   
  Like for NFB-6 , a "paired" DAC comes with the SA-1 (but you can use what ever DAC you want this )
   
  http://www.audio-gd.com/Pro/SA/SA1/SA1EN.htm


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## darren700

I currently have the c2-Sa I was waiting for these to come out as Kingwa mentioned them to me.
Looks sweet but no balanced input kills it for me. Ill stick with the c2-S.A. and Schiitt mjolnir I preordered.


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## .Sup

I would rather get this than NFB 6 because there are no SMD components.


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## IndieScent

Just when I already given up on acquiring their diamond differential stuff they churning out a new one...


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## BournePerfect

I am placing my order for the new dac tomorrow since it's the highest-end single-ended dac they carry, and should compare very well to the old Ref 9 (Diamond Differential too) that I once owned. The amp should be a spectacular performer as well, if my former C-2 SA was any indication. I would buy that too in a heartbeat, but I have a ZDSE arriving in another couple of weeks so there's no need. Kind of wish Kingwa would make another totl SE dac though...
   
  -Daniel


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## Utopia

I'm trying to understand the differences between the SA-31 and the C-2.2 that Audio GD currently offers. As I understand it, this new amp is closer to the older C2-SA, but was the C2-SA better than the C-2.2?


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## .Sup

utopia said:


> I'm trying to understand the differences between the SA-31 and the C-2.2 that Audio GD currently offers. As I understand it, this new amp is closer to the older C2-SA, but was the C2-SA better than the C-2.2?



SA usually means its more musical


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## WiR3D

Quote: 





.sup said:


> SA usually means its more musical


 
  mmm I like, aslong as its not too tubey.
   
  The question now is how does the SA-1 stack up against the Yulong D100 or D18?


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## runswithaliens

With *10 WATTS* output won't it get to ear-splitting levels very quickly giving you very little useful range on the volume knob where channel imbalance is most likely?  I would love to order an Audio-gd single-ended amp/pre-amp with a remote, but that 10 watts seems ridiculous except as maybe a one-off specialty amp for the Hifiman HE-6.


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## IndieScent

Quote: 





runswithaliens said:


> With *10 WATTS* output won't it get to ear-splitting levels very quickly giving you very little useful range on the volume knob where channel imbalance is most likely?  I would love to order an Audio-gd single-ended amp/pre-amp with a remote, but that 10 watts seems ridiculous except as maybe a one-off specialty amp for the Hifiman HE-6.


 

 power not necessarily mean loudness, the gain more involved when it come to loudness. also Audio-Gd use digital relay volume so channel imbalance is not a problem.


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## runswithaliens

Quote: 





indiescent said:


> power not necessarily mean loudness, the gain more involved when it come to loudness. also Audio-Gd use digital relay volume so channel imbalance is not a problem.


 
   
  Thank you for that information IndieScent - that is very useful to know.  Now I feel a bit foolish for saying it was ridiculous to have 10 watts available.  
	

	
	
		
		

		
		
	


	



   
  Would having all that extra power available be a benefit for dynamic peaks/impact and bass slam? I wonder if that would also be true then in its role as a pre-amp?  If I prefer to listen at what are probably lower volume levels than many, I should then probably get the +/-5db option for gain rather than the 0/+10 option (for Senn HD650s and Fostex T50RPs (not yet modified)?
   
  On a further and more speculative note; with 10 watts available into 40 Ohms, I wonder if he could have put speaker taps on the back as well as it must put out a decent amount o' power into 8 ohm speaker loads... if technically possible.


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## runswithaliens

Bump for any speculative comments from any seasoned Audio-gd fans about this amp.  What should we expect from a "[size=x-small]*Fully  discrete Diamond Difference design"*[/size] which "[size=x-small]retains rich details and high clarity with its abundant music flavor with wide and deep sound stage"[/size]*[size=x-small]?[/size]*
   
  Thinking about pairing the NFB-3.2 DAC with this as I can't quite see spending the extra $550.00 on the matching SA-1 DAC despite the allure of owning an Audio-gd PCM1704UK based DAC...


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## IndieScent

Quote: 





runswithaliens said:


> Thank you for that information IndieScent - that is very useful to know.  Now I feel a bit foolish for saying it was ridiculous to have 10 watts available.
> 
> 
> 
> ...


 
   
  well some amp designer believed that is one on the advantage when you fully and properly powering your can IIRC. as for speaker taps, cant comment much as I myself not that much knowledge how much difference in design or component might be needed needed for power amp.
   
  Quote: 





runswithaliens said:


> Bump for any speculative comments from any seasoned Audio-gd fans about this amp.  What should we expect from a "[size=x-small]*Fully  discrete Diamond Difference design"*[/size] which "[size=x-small]retains rich details and high clarity with its abundant music flavor with wide and deep sound stage"[/size]*[size=x-small]?[/size]*
> 
> Thinking about pairing the NFB-3.2 DAC with this as I can't quite see spending the extra $550.00 on the matching SA-1 DAC despite the allure of owning an Audio-gd PCM1704UK based DAC...


 
   
   
  if you can afford it I would suggest get the PCM1704UK DAC as the chip is no longer in production iirc and Audio-Gd might be the last one with it on stock 
	

	
	
		
		

		
		
	


	




.


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## HaVoC-28

Quote: 





indiescent said:


> well some amp designer believed that is one on the advantage when you fully and properly powering your can IIRC. as for speaker taps, cant comment much as I myself not that much knowledge how much difference in design or component might be needed needed for power amp.
> 
> 
> 
> ...


 
  Hum ? where did you read that PCM1704 are no longer in production ? 
   
  http://www.ti.com/product/pcm1704 according to this , production is not yet finished , but could be terminated any time soon .   
   
  It will be when labelised like that : http://www.ti.com/product/pcm63
   
  I know that a time Audio GD claimed that PCM1704UK was over peraphs their chinese distributor was told from ti that PCM1704 was over , but peraphs with huge demand , TI extended PCM1704 life time for a bit . " TI want to discontinued PCM1704 but there are still a lot hi-end fans love the real sound of the PCM1704UK." (From Audio GD , means that PCM1704UK still avaliable but no one knows when it will be definitively over)
   
   
  Any way i am saving to get one of this DAC with PCM1704UK (Ref 5.2 in mind) . But if i miss it , i could pass without it 
	

	
	
		
		

		
		
	


	




 , peraphs waiting for some NFB-7.1 that appear time to time


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## IndieScent

Quote: 





havoc-28 said:


> Hum ? where did you read that PCM1704 are no longer in production ?
> 
> http://www.ti.com/product/pcm1704 according to this , production is not yet finished , but could be terminated any time soon .
> 
> ...


 
   
  I stand corrected then. I guess I got the impression by reading on Audio-gd site, but then again raising prices means less stock usually.


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## IndieScent

so, did anyone ordered and already recieved their amp? curious about the sound of the new ones.


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## JWahl

Yes, I am also looking forward to any impressions of this amp also.  I picked up the matching SA-1 DAC a few weeks back and am loving it so far.  Currently waffling between getting this, the Schiit Mjolnir or Bryston BHA-1 for my HE-6.  Leaning most toward this amp now given the higher power and that the DAC sound signature has seemed to pair well with the HE-6.


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## nigeljames

Why not the Master-8?


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## JWahl

I've definitely considered it but I'm really liking the diamond differential sound.  Or it could just be the PCM-1704 sound that I like, It's hard to say.  I've previously owned an NFB-1ES DAC which is ACSS and Sabre based and it was good but I much prefer the SA-1. 
   
  Plus the SA-31 actually puts 1 more watt into 50 ohms than the Master 8 and it's single ended.  Here's to hoping Audio-GD makes a Reference 8.1 and Master-SA, or even just a diamond differential version of the Reference 10.


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## .Sup

Any more impressions on this amp?


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## FauDrei

It is a bit hard going consciously from full fledged balanced ACSS to "ordinary" single ended voltage driven RCA connections... It's like willingly stepping back into long forgotten realm where structure and quality of interconnects significantly affect the final sound.

 This is the first impression you get when considering SA-31.

 ...and it turns out to be true. True in the sense that RCA interconnects to SA-31 do affect the sound much, much more than ACSS connectors ever did.

 That and initial "whiteness" in the sound while six big SA-31 PSU caps were(/are) forming are the only sound related drawbacks that I've experienced so far. Initially, Roc (over ACSS; modded) was so much "blacker" and clearer that it was bordering to an "What I got this for?" situation.

 After 50 hours or so of cap forming I think I begin to understand SA-31. It's rather odd story, but I'll try to explain...

 I ordered SA-31 with two pairs of XLR inputs. Do not be fooled, SA-31 DOES NOT HAVE differential XLR inputs, nor it has ACSS inputs. It was just a silly whim of mine which insisted on connecting all four channels of RE-1/7 to this single ended pre/headamp.

 It works, sound is a nuance more detailed than SE connection, but I might have misinterpreted this because of higher XLR signal levels. But - DO NOT DO IT. To listen to differential signal on SA-31 you have to alter your power connections and follow very strict rules which limit the functionality of this headamp. It is really not worth it and I'll try to picture why is it so in a moment...

 In my correspondence with KingWa I inquired about diamond differential amplification and asked whether "SA" in SA-31 means abrrevation of "Sansui" as first(?) company that used such topology in it's amps. Well - he said it does not. He also explained that Sansui's implementation was the fist generation of diamond differential design that was non-symmetrical, limited and not that good by today's standards. He went on and stated that SA-31's topology is based on Accuphase early 90's A-100 class A monoblocks - a very high performance symmetrical diamond differential design.

 Whoa, Accuphase! FeelGoodFactor+(A)100 
	

	
	
		
		

		
			





 I immediately started digging information on A-100. I have found "endlessly powerful", "rich" and "strong sense of space".

 ...and similar adjectives can be tied to SA-31.

 It adds much harmonics to the sound. I hear those harmonics as vastly enlarged and better defined stage with slightly increased details. Headphones do not sound "in your head" any more but slightly "in front and around you" and I have found it is much easier to listen to headphones for very long this way. Even with LCD-2s, which is quite a feat in my book.

 What really struck me was the realization that this harmonic effect is better when listening to single ended source (RCA connection from RE-1/7) than differential one (XLR connection from RE-1/7). It finally clicked to me why he, who would design even his iPod balanced, did not bother to create four channel SA-31. Good choice.

 So, now I am, after years of RCA abstinence, in a hunt for decent OCC RCA interconnects. My Van Den Hull Ultimates are too dark, my old DIY silver RCAs are hyperdetailed but zingy.

 It sounds warmer than Roc. But KingWa warmer, no hot chocolate tube amp warmer. This would mean that if you would hypothetically connect in series two SA-31s the resulting sound would not be the same as single SA-31 sound but just a tad more colored. With two Roc-s I could almost bet vast majority of us could not tell the difference.

 I have tried using jumpers to get warmer sound ("warmer sound 1" and "warmer sound 2" from SA-31 "Use Manual" page) - music does get "rounder" and warmer but I think less detailed. Will eventually re-evaluate, but for now it is no jumpers and all the details for me.

 To be stereotypical - SA-31 has the control, PRaT and dynamics of SS with "airness", "musicality" and definitely "spaciousness" of tube amps. We'll see how this changes when New Toy Syndrome wears.

 Endgame? No. But could be for some.

 Good amp? Absolutely. Especially if you have single ended hairdryers that need proper amping.


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## .Sup

That is one of the more interesting posts I have read lately, here. Thanks for your impressions. I already have a neutral amp and this could be a nice addition. I would like to see if HE-500 need more than my Auditor can output and this should provide if needed.


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## i019791

Quote: 





faudrei said:


> It is a bit hard going consciously from full fledged balanced ACSS to "ordinary" single ended voltage driven RCA connections... It's like willingly stepping back into long forgotten realm where structure and quality of interconnects significantly affect the final sound.
> 
> This is the first impression you get when considering SA-31.
> 
> ...


 
  All this description (tube sound etc) of SA-31 fits exactly with my impressions of the "matching" Audio-gd SA-1 Dac, which I got last month, when paired with the Violectric V200 amp. Note that the Violectric was not to my ears similarly "tubey" by itself, as I had a normal slightly warm SS sound when pairing it with Audio-gd NFB-3 or (with the Dac of) Audio-gd NFB-10SE.


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## JWahl

Thanks for the impressions.  I too had the SA-1 DAC and also agree with the above poster. Unfortunately, I had to sell it and my HE-6 for financial reasons.  I may pick it up again when I rebuild my setup, especially with the new usb section that they've added.
  
  I imagine it should drive the HE-6 decently but I'm wondering if it would be overkill for HD800.  I think the sound signature might benefit it though.
  
 I may get an HD800 instead when I rebuild or get the HE-6 again.  I love the texture and attack of the HE-6 but I also like a good soundstage, and it seems like this amp could bring out a good soundstage in the HE-6, based on the impressions.


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## pdnj77

I am a newbie, so you will have to forgive me if my questions seem foolish.
The HE500 is rated at 1 watt , so will that mean that the volume control can be turned to only 10percent of the total travel to achieve full volume?
Beyond that , is there not a risk of blowing up the drivers?

pdnj77


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## .Sup

I'm not sure what the 1w requirement is honestly. If you put 1w into them your ear drums will rupture.


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## FauDrei

Hi pdnj77, welcome.
   
  Just few hours ago I've went through longer AC/DC session with HE-500 through SA-31 at volume 45-50 out of 80 on high gain.
   
  This amp kicks the crap out of HE-500. But HE-500 can take it. Without distortion. Excellent, excellent pairing.


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## Mad Lust Envy

I want this yesterday. Audio-GD made a fan out of me with their NFB-5 DAC/AMP, and I was intent on upgrading to an NFB3+C-2.2... (at that time), but now with THIS amp... I'd spend more on it, and perhaps an ODAC. Wishful thinking anyways.


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## Currawong

The purpose of having such exceedingly excess power is not because it is necessary, but to ensure that no matter how crazy things get, the amp is always performing well within its limits.
   
   


> So, now I am, after years of RCA abstinence, in a hunt for decent OCC RCA interconnects. My Van Den Hull Ultimates are too dark, my old DIY silver RCAs are hyperdetailed but zingy.


 
   
  You want to wait until a pair of The Orchids come up on Audiogon. They are the answer.
   
  Here's a funny story I don't tell often, but the mention of balanced amps reminded me of it. A number of us had gotten into rolling the HDAMs into anything and everything OPAMP-using we owned when I noticed that Kingwa also made headphone amps, such as the C-2C, the predecessor of the C2. Even though it used an ACSS gain circuit, it was slightly coloured and a very nice match for the sometimes tame-sounding HD-600s. Not actually understanding how balanced amps worked at the time, I asked Kingwa in innocence if the C-2C could be made into a balanced amp. He stated he could put two of them in a box, but I declined the offer. Almost exactly a month later he emailed me out of the blue to tell me had designed the Phoenix.... 
   
  I sometimes miss the C-2C. When I plugged the HD-600s into the Phoenix for the first time, it was distinctly better, but wasn't nearly as much fun to listen with as the C-2C was.


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## pdnj77

Looks like good news for me.
If the SA31 works on both 50 and 60 cycles AC current, I can use it with a step up/step down transformer, whether I am in India or the US.
plus of course a big saving if it is at least equal to the Yulong a18


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## WiR3D

Quote: 





pdnj77 said:


> Looks like good news for me.
> If the SA31 works on both 50 and 60 cycles AC current, I can use it with a step up/step down transformer, whether I am in India or the US.
> plus of course a big saving if it is at least equal to the Yulong a18


 
  was actually thinking those 2 would be competitors. But I suspect the SA31 would be more coloured, where the A18 is more analogue. (Ofcourse I have heard neither.)


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## .Sup

I have a question for owners: can you select to which headphone out sound is outputted or are both outputs active at the same time?


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## FauDrei

Both at the same time.


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## .Sup

faudrei said:


> Both at the same time.



Thanks for the reply Fau. I was hoping to have both headphones plugged in at the same time and then switch to whichever I would like to listen with. Did you get yours with dual 6.3mm outputs?


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## FauDrei

No. Almost all my phones are 4-pin XLR terminated.


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## pdnj77

I am 99 percent sure that the SA31 is the amp for me and my HE500's.
It obviously has more than enough power,and you have have found it to sound good
Does it have any background noise? How hot does it run. How is the service now? Some time ago,one member complained about delays in shipping.
Thanks in advance


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## FauDrei

No background noise. It runs warm, I'm guessing - around 40°C in 25°C room. Do not know what to answer about service - I have always had good experience in dealing with KingWa & his pals at A-GD.
   
  BTW, my SA-31 has settled. It gained "blackness" comparable to Roc, but it has much "richer" sound than Roc. I've also re-evaluated "warm sound 1" and "warm sound 2" settings - it "*bolds*" the sound over whole frequency range and so it adds heavier stomp to lower notes too. No detail masking as I reported first time. "Warm sound 2" is perhaps too much, but "warm sound 1" is just about right for me. I might even give up on my modification plans for it... 
	

	
	
		
		

		
			





 not sure that Mundorfs can add anything more to the sound.


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## pdnj77

Thanks, Fau,
Very kind of you to clear my doubts.
Now to take the plunge
pdnj77


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## Mad Lust Envy

I just with it had an amazing A-GD volume knobs and not digital buttons.


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## rocksteady65

Sorry? What do you mean exactly?


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## .Sup

rocksteady65 said:


> Sorry? What do you mean exactly?


replace "with" with "wish" and it should be clear


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## rocksteady65

Ah, thanks Sup. Yes, it does make sense now.


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## HaVoC-28

Quote: 





.sup said:


> replace "with" with "wish" and it should be clear


 
   
  Peraphs you could ask King Wa for a custom one , if he had parts ... he could do that i think .


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## Mad Lust Envy

Sorry, yeah, wish. Dunno why I wrote with. :rolleyes:


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## FauDrei

Well, yes... digital up/down buttons are no match to knob turning intuitivity. It takes some time to get used to buttons.
   
  But beside that - it performs flawlessly: it is not in signal path, channel imbalance is non-existent (useful in late night low level listening), has enough steps and gain settings are well chosen (+10dB/+0dB). I've opted for additional volume board (+5dB/-5dB), but had not have reason or urge to swap it in yet.
   
  OtOH, you can get remote which sets you back for additional $50 which is,perhaps, a bit steep compared to whole unit cost... it is "indestructible" (aluminum) but rough on some edges (DIY fixable)... it has no repeat feature for volume up/down functions which KingWa explained as intentional - so that unit does not mix-up remote commands; not so sure this was not doable but funny thing is you can change volume faster with fast repeated presses on remote control than with holding volume up or down button on SA-31... it has no mute button (workaround: swap to "empty" input channel)... it has no standby (on/off) button... and I miss the most a button to dim or turn off the display (yes... again lazy late night listening).
   
  Knowing all this now - I would order remote again... it is priceless in certain lazy lay back moments.


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## Evshrug

mad lust envy said:


> Sorry, yeah, wish. Dunno why I wrote with. :rolleyes:




Maybe you are having so much fun, you are developing a lithp?


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## Clemmaster

faudrei said:


> Well, yes... digital up/down buttons are no match to knob turning intuitivity. It takes some time to get used to buttons.
> 
> But beside that - it performs flawlessly: it is not in signal path, channel imbalance is non-existent (useful in late night low level listening), has enough steps and gain settings are well chosen (+10dB/+0dB). I've opted for additional volume board (+5dB/-5dB), but had not have reason or urge to swap it in yet.
> 
> ...


 

   
  But it has the gain button just next to the volume ones, which can be dangerous if you accidentally press it when you were previously set on low gain...


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## tim3320070

Boy I wish there was a Master-SA amp to go with my Ref-8 in fully balanced mode but maybe not necessary? I do like the warmer, thicker sound but need that clarity I get from my Master-5.


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## FauDrei

Do not be fooled Tim - SA-31 is warm and you can also choose level of "warmness", but unlike tube and warm SS amps that I heard - you get all the details and the background is just black. Due to added harmonics details are better perceived than through Roc and that is something if you consider that Roc is connected through balanced ACSS and SA-31 is hooked up with "just" plain old single ended voltage RCA connection. It makes you wonder...


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## tim3320070

Kingwa says there is not demand enough for a fully balanced SA series amp. I may still consider this for my bright headphones. I like warm but detailed- my speakers are like this.


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## Mad Lust Envy

I'm tempted on using my Paypal credit for the SA-31.


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## tim3320070

Giving this a shot- will post impressions


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## WiR3D

none of you guys feel like whacking this with some D5000/D7000? It could either be magical (WA6SE like) or completely unsuited. I am interested.


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## FauDrei

Sorry... when I was about to pull the trigger on D7000 - HE-5 came around... and I've never looked back at dynamic headphones.


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## Mad Lust Envy

Questions about the SA-31.

I see the inputs are very separated for the left and right channels. I'm used to amps having the red/white inputs right next to one another.

Does the SA-31 come with RCA cables? I don't have any that are so far separated.


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## tim3320070

AGD sells some for $23


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## Mad Lust Envy

NVM, Didn't realize all I had to do was cut something off the RCA cable and it allowed me to spread them apart easily. No new cables needed.

Still, I don't understand why the inputs for each channel are so separated on the SA-31.

In any case, I hate myself, but I just sent an email for the order w/remote and two 6.3mm inputs.


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## Mad Lust Envy

kingwa said:
			
		

> The NFB 5 have the ALPS volume control port, but the SA31 have the relays volume control board, the ALPS port must have the channel imbalanced but the relays volume control without channel imbalance.
> We can't change the SA31 to knob control.
> Kingwa




Ah well, ordered the SA-31 with remote control and two 6.3mm inputs. I have zero use for XLR.


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## .Sup

mad lust envy said:


> Ah well, ordered the SA-31 with remote control and two 6.3mm inputs. I have zero use for XLR.



I am still considering getting this and while I don't have any balanced headphones its still nice to have an amp with XLR output in case I get a balanced headphone, HE-6 or the likes


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## Mad Lust Envy

The amp's not balanced, so either way, the XLR would be useless. From what I've seen, people who terminated their headphones in XLR have a standard adapter as well.


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## tim3320070

Not useless for me- I have the Master-5 and I can switch back and forth without needing the extra cable banging around. But it is a little odd.


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## tim3320070

Wow, okay, this amp is really good. I currently have the "warmer 2" setting going which is nice with my brighter DT770/600's- it definitely reduces sibilance in female vocals but keeps all the detail- it seems to take the "edge" off of recordings that are bright- think Lyle Lovett for instance. It's soundstage is not as wide or deep as my Master-5 but it's different tone is a good offset to it. Plenty of power on tap.
   
  I think this amp would be a great pairing with brighter headphones or anyone who likes smoother treble (yet still extended enough), or maybe has a brighter source/ DAC. 
   
  Another quality amp from Kingwa.


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## FauDrei

Congrats Tim. Glad you like it.


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## Mad Lust Envy

I'm gonna be paiairng it up with the DT990s which is very bright. Sounds like a quality combo. I may even go old school Hifiman and get the HE-4 which could use all that power.


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## Clemmaster

Quote: 





mad lust envy said:


> I'm gonna be paiairng it up with the DT990s which is very bright. Sounds like a quality combo. I may even go old school Hifiman and get the HE-4 which could use all that power.


 
   
  Unless you really like the HE-4 sound signature and your budget does not allow you to get the HE-5LE (which has a similar signature) I would not recommend this phone. I own it as well as the HE-500 and the performance level is definitely not the same. From what I heard, the HE-400, however, is really close to the HE-500 in most aspects but it has a dark sound signature that might not pair well with the SA-31 in this case. I would go NFB-6 + HE-400 or SA-31 + HE-5LE depending on budget.


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## Mad Lust Envy

I already owned and loved the HE-4. I wouldnt be using the extra warmth settings with it. The HE500 wouldnt have the bass presence I want. Even the HE400 didnt have enough. From memory, the HE4 was like the DT990, just darker.


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## Andolink

Quote: 





clemmaster said:


> Unless you really like the HE-4 sound signature and your budget does not allow you to get the HE-5LE (which has a similar signature) I would not recommend this phone. I own it as well as the HE-500 and the performance level is definitely not the same. From what I heard, the HE-400, however, is really close to the HE-500 in most aspects but it has a dark sound signature that might not pair well with the SA-31 in this case. I would go NFB-6 + HE-400 or SA-31 + HE-5LE depending on budget.


 
  I'm running the HE-500 from the NFB-6 (fully balanced) and it sounds terrific though I have no other phones or amps to compare it with.


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## tim3320070

The SA-31 is not dark- it's "Kingwa dark" meaning subtly warmer that ultra neutral.


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## Mad Lust Envy

tim3320070 said:


> The SA-31 is not dark- it's "Kingwa dark" meaning subtly warmer that ultra neutral.




Exactly. Having owned the NFB-5, I know what to expect. 

The NFB-5 sounded glorious with the HE400. Since the HE-4 is slightly brighter than the HE400, I wouldn't expect overly dark sound anyways.

First things first: waiting for the SA-31 to arrive to test with the two 990s I have. Then I'll see if I have a desire to get the HE-4.



PLEASE tell me that means it's on it's way!


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## tim3320070

Yes, it's on the truck for delivery


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## Mad Lust Envy

The wait is killing me.


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## HaVoC-28

Quote: 





mad lust envy said:


> Exactly. Having owned the NFB-5, I know what to expect.
> The NFB-5 sounded glorious with the HE400. Since the HE-4 is slightly brighter than the HE400, I wouldn't expect overly dark sound anyways.
> First things first: waiting for the SA-31 to arrive to test with the two 990s I have. Then I'll see if I have a desire to get the HE-4.
> 
> PLEASE tell me that means it's on it's way!


 
  Ha fun with your new toy 
	

	
	
		
		

		
			





 and try to stay alive until it come to your home ^^


----------



## WiR3D

Quote: 





tim3320070 said:


> Yes, it's on the truck for delivery


 
  No I just hijacked the truck, he's never getting it


----------



## Mad Lust Envy

It's here!


----------



## HaVoC-28

Quote: 





mad lust envy said:


> It's here!


 
   
  Now first impressions , and later when you will be used to it (and the unite burned for who believe in such things) .


----------



## tim3320070

I suggest letting it warm up for 1/2 hour or more (if you can)


----------



## HaVoC-28

Quote: 





tim3320070 said:


> I suggest letting it warm up for 1/2 hour or more (if you can)


 
  What kind of torture is that ? when i got a new good i want to try it as fast as i can 
	

	
	
		
		

		
			





 , even if A-GD beneficit from warm up thing that i never paid attention to , 30 min is a long time for a comparison 
	

	
	
		
		

		
		
	


	




 sorry i don't find Audio memory enough accurate for this kind of thing , only having two SA.31 letting one warm up 30 min or more and compare to the one you just power up (or any Auther material that would need "warm up") , if not , no  valid comparison and mostly be things that occur in your head IMO . 
   
  And even if warm up help it will not sound bad without warm up .


----------



## Mad Lust Envy

Just got it set up, temporarily feeding the ODAC to the E9K - Line Out - SA-31 (wanted to do it this way as the SA-31 has pre-amped outs.)

DT990/250:

On high gain, the volume was at 30/79. On low gain, about the same volume is at 64/79. That was on one song. The next song was a bit louder, so I turned it down a bit.

Lol, I subconsciously reached for the 'volume knob' to turn it down... sigh, looks so much like my old NFB-5. Those wounds are still fresh, lol.

First things first.

Amp differences aren't huge (unlike a lot of head-fi, I don't suffer from expectation bias). The E9K is definitely dryer. The SA-31 favors the low end slightly vs the E9K. The SA-31's treble is less harsh than the E9K. I expect this. That's an A-GD trait. The E9K because it's dryer has slightly more forward mids, but it's thinner sounding. The SA-31's voicing is fuller, and the sound is more cohesive and blended in...more natural. And this is exaggerating the differences. I bet less than head-fi ears wouldn't hear the diff.

These are preliminary impressions just TWO songs in, quickly swapping from the E9K to the SA-31 at nearly matched decibel levels.


----------



## Mad Lust Envy

Oh yeah, I got mine with the remote.

The package came with some chip (looks like a secondary chip for the remote). Please confirm, and if you got an extra too.

That and some... mini pieces of plastic? I'm not not sure what they are. They definitely go inside the SA-31. I wonder if these are the jumpers needed to change the warmth levels?

Anyone that can confirm what they are? I hate having things that I have no idea what they are for.

I'll take a pic later. I have to sleep.

Also, gotta mess with the warmth settings, as well as let it 'burn in', if that'll even do anything. I doubt it, but I'll do it anyways.


----------



## kidchunks

Quote: 





mad lust envy said:


> The package came with some chip (looks like a secondary chip for the remote). Please confirm, and if you got an extra too.
> That and some... mini pieces of plastic? I'm not not sure what they are. They definitely go inside the SA-31. I wonder if these are the jumpers needed to change the warmth levels?
> Anyone that can confirm what they are?


 
   
  Jumpers, most of his products come with them which can change certain features of said amp/dac. As for the SA-31, I would check the manual.
   
http://www.audio-gd.com/Pro/SA/SA31/SA31EN_Use.htm
   
  Enjoy!


----------



## Mad Lust Envy

kidchunks said:


> Jumpers, most of his products come with them which can change certain features of said amp/dac. As for the SA-31's case, I would check the manual.
> 
> http://www.audio-gd.com/Pro/SA/SA31/SA31EN_Use.htm




Saw that, just that there were so many, lol.


----------



## kidchunks

Quote: 





mad lust envy said:


> Saw that, just that there were so many, lol.


 
   
  Kignwa likes to throw in a few extras. 
	

	
	
		
		

		
		
	


	



   
  My NFB-10.2 came with a bunch also.


----------



## Mad Lust Envy

Ok, so my test for warm 1 and warm 2 have been directly vs the E9K.

The SA-31 (with no warmth jumpers) and E9K are close in tonality (this is just a tonality comparison), with the E9K being just a smidge brighter.

Warm 1: It does sound just a little bolder than no jumpers, but it's like VERY slight.

Warm 2: I honestly don't hear a diff from Warm 1.

I'll have to do more testing to hear exactly what changes.

Tube amps definitely alter the sound quite a bit more than these jumpers.

I must say though, the DT990s sound glorious off the SA-31 with the warm 2 setting (all 4 jumpers in).

One thing I notice is that the SA-31 controls the 250ohm's bass quite a bit compared to the E9K. Ironically, I prefer the looser bass on the E9K. However, on the 600ohm, it brought out the bass to where I feel it almost rivals the 250ohm's bass (both off the SA-31).

If I was keeping the E9K, I'd definitely keep the 250ohm. Off the SA-31, they're both near identical, so I'll stick to the slight refinement of the 600ohm.

edit:


To update from the last post, yes, the SA-31 with warmth jumpers all in, really add all I wanted from the DT990/600. It's not a big difference, but it's enough.

I would say the DT990/250 off the E9K has the most bass presence (but least control) out of all the combinations today (by a hair). However, the refinement and less edge in treble of the SA-31 + DT990/600 wins out.

Out of the E9K, the 250 has noticeably more bass than the 600. Out of the SA-31, that gap becomes smaller, to the point that I can't tell the bass presence apart when quick-swapping from the E9K/250 to the SA-31/600.

I'm gonna pack up the DT990/250 and E9K today. I've heard enough...

Am I gonna keep the 600ohm? Probably not, as Amazon is selling them Like New for $50 less than I paid. Since I'm within my return window, I'll save some money by getting another pair. Unless they wanna just refund me that price difference.

To identify between tthe different warmth settings of the SA-31, I basically went from no jumpers to all jumpers. The biggest difference is in the bass. The bass gets fuller with all four jumpers in compared to no jumpers. It does sound a hint darker... but it's minute.

I'd say for the sake of liking warmth in your cans, all 4 jumpers are not a BIG difference from no jumpers, so you may as well have them all pushed in for maximum warmth.

edit:

The differences between the SA-31 and E9K were more obvious on the KSC35. The SA-31 was considerably warmer.

I guess warm 2 may be a bit much for warmer sounding headphones like the KSC35. I preferred it off the E9K, and the E9K isn't technically a proper match for it due to high output impedance. I think the jumper settings are headphone by headphone basis. You'd do fine with no jumpers at all for all headphones, but some headphones can benefit from extra warmth, and some can be impacted negatively. So all in all, if you're lazy, stick to no jumpers. If you wanna tweak per headphone, leave the top unscrewed for easy jumper switching.


----------



## AManAnd88Keys

Quote: 





mad lust envy said:


> Ok, so my test for warm 1 and warm 2 have been directly vs the E9K.
> The SA-31 (with no warmth jumpers) and E9K are close in tonality (this is just a tonality comparison), with the E9K being just a smidge brighter.
> Warm 1: It does sound just a little bolder than no jumpers, but it's like VERY slight.
> Warm 2: I honestly don't hear a diff from Warm 1.
> ...


 

 Thanks for your impressions, this really helps me to understand what kind of amp the Sa-31 is!  Can you say anything about detail, soundstage, instrument separation and so on at this point?


----------



## tim3320070

Quote: 





amanand88keys said:


> Can you say anything about detail, soundstage, instrument separation and so on at this point?


 
  It's got all those in spades. Detail without fatigue.


----------



## AManAnd88Keys

Quote: 





tim3320070 said:


> It's got all those in spades. Detail without fatigue.


 

 Great 
	

	
	
		
		

		
		
	


	




 How does it compare to other amps that are similarly priced (Lyr for example)?


----------



## Mad Lust Envy

I had the Lyr. The SA-31 doesn't have the tube like warmth of the Lyr. Ths SA-31 is more neutral than the Lyr with two sets of tubes I tried.

I felt the Lyr had a big bottom end and slight mid recession.

I will be getting my HE-4 in a few days, which was the headphone I used with the Lyr last year. The Lyr was great with it, but the Lyr had a slight hum, whereas the SA-31 is dead silent.

I think both are great so far, though the Lyr allows tube rolling to further alter the sound to your liking. I personally prefer the SS sound, so I like the SA-31 more.


----------



## Mad Lust Envy

I've come across my first problem. The SA-31 at high gain and max volume can't as much as drive my DT990/600 for ANY of my portable sources, whether the Galaxy Note II, PS Vita, or 3DS. I didn't have that problem with the E9K. The SA-31 is absolutely worthless with those sources. When you have to max out the SA-31 completely just to get a moderate volume out of your phone... you know there's a problem....

I'm gonna wait for the HE-4 to arrive and see how the SA-31 handles it. Perhaps it will function better at low ohms.

The SA-31 is supposed to be a LOT more powerful than the E9K (700mw at 600ohm vs 80mw at 600ohm), so what gives?

I noticed that on the E9K with the ODAC, I use High gain and have the volume at about 40% of the E9K's knob. The SA-31 is at over 50% (41) of it's max volume (79).

Did I confuse the SA-31 for being really powerful because of it's power specs? Because if so, I'll have to talk to Kingwa about this, since I'm afraid that the SA-31 wouldn't drive planars as well as I thought. I've only used it with the DT990's so far (and the super sensitive KSC35), and the 600ohm isn't exactly hard to drive in terms of decibel level, yet they're struggling off my portables+SA-31.

I can also hear the other input's music playing (lowly) when I switch to an unused input. For example, if I'm playing music on Input 3, and switch to input 4, I can hear the music still playing, faintly. The input does have to have nothing plugged in though, so it's not really an issue, as when I do have RCAs plugged in, I can't hear anything.


I want this amp. However for the $600+total it cost to get it (w/remote), I expect POWER and perfection.


----------



## Clemmaster

In general, DAPs output is really weak in term of voltage level. They are way below the standard line level and you need an amp with a pretty high gain to make it work to proper volume. No matter how powerfull your amp is, if it does not have the proper gain to work with the DAP it will be a no-go.
   
  My dad is having the same problem with his setup: cowon J3 -> m-stage -> HE-4. Even at max gain (+20dB) and both the j3 and m-stage maxed out, the volume is still slightly less than what he likes. It's just about perfect for me but then I have no headroom on quieter tracks. It's doable with the HE-500 but not the HE-4 (lower sensitivity).
   
  The SA-31 is even lower in gain (+12dB if I remember correctly) so I would be even lower, despite its 10W power output capacity (40x that of the m-stage).
   
  You need another gain in between if you want to use your portable source with it. Or you should ask to change the high gain to >20dB


----------



## Mad Lust Envy

clemmaster said:


> In general, DAPs output is really weak in term of voltage level. They are way below the standard line level and you need an amp with a pretty high gain to make it work to proper volume. No matter how powerfull your amp is, if it does not have the proper gain to work with the DAP it will be a no-go.
> 
> My dad is having the same problem with his setup: cowon J3 -> m-stage -> HE-4. Even at max gain (+20dB) and both the j3 and m-stage maxed out, the volume is still slightly less than what he likes. It's just about perfect for me but then I have no headroom on quieter tracks. It's doable with the HE-500 but not the HE-4 (lower sensitivity).
> 
> ...




Thing is, the E17 (a portable amp) could drive the DT990/600 about as loud as the SA-31 off those portables. It doesn't make any sense. I'm sincerely hoping it's an issue just with high impedance. The KSC35 can barely go into high gain... (single digits off the ODAC).

The 990 does get ear shatteringly loud when using the Mixamp to SA-31 or ODAC to SA-31 (albeit at just over the SA31's max volume on high gain). I distinctly remember the HE-4 needing a crapton more than anything else I've driven, even off the Lyr (though with plenty of headroom). This scares me. If the SA-31 needs to be nearly maxed to be at a loud volume.... I'm definitely not going to be happy. I expect this amp to have as much, if not more headroom than the Lyr. I'm beginning to think I chose the wrong amp. The HE-4 will be the deciding factor. Tuesday can't come soon enough. If I have to ship the SA-31 back and be stuck with NO amp for two hard to drive cans... ugh... this is seriously going to irk me.


----------



## HaVoC-28

Quote: 





mad lust envy said:


> Thing is, the E17 (a portable amp) could drive the DT990/600 about as loud as the SA-31 off those portables. It doesn't make any sense.
> The 990 does get ear shatteringly loud when using the Mixamp to SA-31 or ODAC to SA-31 (albeit at just over the SA31's max volume on high gain). I distinctly remember the HE-4 needing a crapton more than anything else I've driven, even off the Lyr (though with plenty of headroom). This scares me. If the SA-31 needs to be nearly maxed to be at a loud volume.... I'm definitely not going to be happy. I expect this amp to have as much, if not more headroom than the Lyr. I'm beginning to think I chose the wrong amp.


 
  As reported By clemmaster the fact is that some DAP , have a weak line out , E17 is a portable amp optimised to be used with such kind of device , for SA-31 seams that not . Regular Line Out are about 2.0V ... Some amp input are less or more sensitive . I experienced that too , with some weak DAP player i have to crank out the volume much more , but depending on wich DAP , Wich Amp it can offer very different results .
   
  And DT-990-600 ohms and HE-4 don't have the same electrical requirement , wait for HE-4 for a final statement ^^


----------



## Mad Lust Envy

That's why I've said that the HE-4 will be the deciding factor. Honestly, the SA-31 sounds amazing off the Mixamp and ODAC. I'm just disappointed that it didn't boost volume enough for my portables. I expected with all that power the SA-31 is claimed to have, to be able to drive stuff even off weak sources. This is definitely not the case. The Sansa Fuze can get really loud with the E9K. The SA-31? Nope. This is truly disappointing.

I don't have high hopes of it doing much better with the HE-4, but we'll see. I hope I'm surprised. The HE-4 is 38ohm, which should take in the maximum power that SA-31 is capable of.


----------



## tim3320070

You can ask Kingwa about adjusting the gain- it might be simple- I have done several mods to his gear with his direction without issue. He is very helpful in this regard.


----------



## Mad Lust Envy

I will try that. Thanks.


----------



## BournePerfect

Don't confuse gain with overall power. For instance the E9/AD2K got louder quicker than my C-2 SA (6W@50ohm!!)-but the E9 sounded awful because of it's high output impedance as well, and the C2-SA sounded absolutely astounding. The best match I ever heard with my AD2000. And stop blaming your WEAK DAP/etc voltage out on the AGD. 
	

	
	
		
		

		
			





 
	

	
	
		
		

		
		
	


	



   
  -Daniel


----------



## Mad Lust Envy

I'm comparing it to the Lyr, which had a lot of power and volume. So far, the SA-31 hasn't been as powerful as I'd hope in volume. Nothing other than the Mixamp and the PC to ODAC has been loud off it.

PS3
Sansa Fuze
3DS
Vita
Galaxy Note II

All have been maxed out on high gain.... and they're barely better than the source's volume. If the SA-31 is truly this finicky, perhaps I made a mistake. The DT900/600 is NOT hard to get to ear splitting levels. Even the E17 goes louder off those sources. Sound quality is worthless if it can't even go loud enough with the headphone and sources I'm using.

If it's the case of it not being good for high impedance loads, then I'll let it slide, and return the 600ohm for a lower ohm 990, but it's still a disappointment.

I really can't wait for Tuesday (it hasn't shipped yet which is odd... I wonder if that Hurricane Sandy is in the path of the delivery... argh). This wait is driving me crazy.


----------



## Clemmaster

Quote: 





mad lust envy said:


> I'm comparing it to the Lyr, which had a lot of power and volume. So far, the SA-31 hasn't been as powerful as I'd hope in volume. Nothing other than the Mixamp and the PC to ODAC has been loud off it.
> PS3
> Sansa Fuze
> 3DS
> ...


 
   
  In your case, the low volume has nothing to do with the amp beeing restricted in power output. Changing your DT-990 to 250ohm won't change a thing.
  Gain is what you lack with the SA-31 for your particular needs (portable sources). You might ask Kingwa about getting a higher gain for those sources (set high gain to 20-25dB).
   
  With a proper line out source (any desktop dac in my case), I can't go past 14-15 on high gain with my HE-500


----------



## Mad Lust Envy

Well, on the PC->ODAC I get the DT990/600 to 40-50 before it's super loud. It's just other sources. Why is the headroom so small?


----------



## tim3320070

My DT770/600 with the little Fiio D03K DAC (fed by a cheap CD changer) gets to painful levels at about 30 on high gain with my SA-31.


----------



## conquerator2

Quote: 





mad lust envy said:


> I'm comparing it to the Lyr, which had a lot of power and volume. So far, the SA-31 hasn't been as powerful as I'd hope in volume. Nothing other than the Mixamp and the PC to ODAC has been loud off it.
> PS3
> Sansa Fuze
> 3DS
> ...


 
   
  Hmm. I don know, it might just be the high impedance phone (I hope), I have no issues driving my pro 900 (I know they are not plannars, but) with a week NFB-16 and the DTS 7.1 converter (came with the turtle beach PX5s)
   
  I cant tur either past 11 oclock, otherwise it gets too loud.
   
  I wouldnt have imagined a gaming console struggling with phones :O
   
  Do let us know how the low impedance HE-4 fare!


----------



## HaVoC-28

Quote: 





conquerator2 said:


> Hmm. I don know, it might just be the high impedance phone (I hope), I have no issues driving my pro 900 (I know they are not plannars, but) with a week NFB-16 and the DTS 7.1 converter (came with the turtle beach PX5s)
> 
> I cant tur either past 11 oclock, otherwise it gets too loud.
> 
> ...


 
   
  The main problem with HE-4 is it's low sensitivity ,  "Efficiency: 86 DB" from head direct wich is much less than your pro 900 rated at 96 db


----------



## FauDrei

Do not worry about HE-4.
   
  HE-5 has similar 86 dB sensitivity at ≈ 30Ω impedance. SA-31 makes HE-5 insanely loud at anything over 40-45 on high gain (+10 dB) ...that is - if you feed your SA-31 with anything that approximates "standard consumer audio" line level.
   
  SA-31 has no headroom? Yeah, right... All that power is there for a reason - and loudness is not that reason in SA-31.


----------



## conquerator2

Ok so for anyone interested, I asked Kingwa about the gain settings, he replied:
   
   
  
 "Yes we can custom order the different gain, the highest is can up to 35DB.
 But higher gain, users want to have take care the source and the signal cable, the noise also will gain more.
 Kingwa"
  
 Im not sure what he meant by the first sentence on the second line though, wha does he mean by "take care the source and signal cable"?
  
 Thanks!
  
 Hope this will also help.
  
 Cya guys


----------



## Mad Lust Envy

Depending on how it works with the HE4, I may ask the to make low gain what high hain is currently, and make high gain 20-25db. I only plan on using major headphones anyways, and the KSC35 sounded fine on high gain, though barely into double digits.


----------



## Kingwa

Quote: 





conquerator2 said:


> Im not sure what he meant by the first sentence on the second line though, wha does he mean by "take care the source and signal cable"?
> 
> Thanks!
> 
> ...


 
  If the gain is 10DB, the source and the signal cable total have 0.1MV noise level, the amp will output around 0.3MV output ( assume the volume is on max position ).
  If the gain is 30DB, the noise become 3MV .
   
  The source noise is fixed, the good shield signal cable can have less noise while transfer the signal .
   
   
  Nowdays, the amp design usually is refer the input signal level around 2V to 3V because most dedicated source have refer this standard  , if the source have quite low output , like 0.7V ,the amp can't have enough gain for the large power output .
   
  If design refer 0.7V input level design, while connect with 2V output level source, the volume just turn several steps, the output have very loud .
   
  This is different to the DAC built in amp , Its DAC output level is fixed  so can easy design the total gain  .


----------



## conquerator2

Quote: 





kingwa said:


> If the gain is 10DB, the source and the signal cable total have 0.1MV noise level, the amp will output around 0.3MV output ( assume the volume is on max position ).
> If the gain is 30DB, the noise become 3MV .
> 
> The source noise is fixed, the good shield signal cable can have less noise while transfer the signal .
> ...


 
   
  Ok thanks for the clarification Kingwa!
   
  So will there be an difference if I connect it like this
   
  Smartphone---NFB-16(DAC mode)---SA-31---HE-500/Pro 900/LCD-2s,etc
   
  or just simple
   
  Smartphone-----SA-31----Headphones(HE-500,etc)
   
  Does the NFB-16 in DAC mode has any effect on incoming gain?
   
  Additionally would you recommend me a custom gain setting for this configuration?
   
  Thanks!


----------



## Mad Lust Envy

I understand, but when I have used other amps of various sizes and power and can get an appreciable volume out of my headphones with the analog sources I use, and cant do the same with the SA31, its problematic, leaving me with being unable to use my expensive amp for anything but a few sources.

I would have to stick to very easy to drive headphones for my phone and other portable devices, or buy a secondary amp that WILL drive them loud enough. This is unnacceptable to me. I got rid of my other amps BECAUSE I thought the SA-31 would have both power and volume for all my devices. All my other amps (aside from the lowly E5, and E7) had the volume for all except the most demanding headphones in the same situations that the SA31 couldn't provide enough volume for. Even the E17 drove the 600ohm to appreciable volume levels off those weak portable sources.

Yes, power =/= volume, but what good is power, if I can't get an appreciable volume? If the SA-31 is THAT picky, then it's not for me. I may as well have gone back to the Lyr.

Now, I'm stuck in probably having to lose MORE money just to ship it back.

Even if it does miraculously drive the HE-4 louder than the 600ohm, it's still useless for my weak sources.


----------



## Kingwa

The phone, game player and the tablets usually have low output level because the battery voltage limit.
  It need the amp have more than 20DB gain for well well but if connect to dedicated DAC or CDP, 20DB is too loud for normal sensivity headphones.
   
  The NFB16 can have higher than 3V output in battery power supply model so it can connect to the SA 31 with enough power output . In USB power supply model its max output level low to around 1V .


----------



## Mad Lust Envy

Kingwa has been very helpful via email. Seems all I need to find is someone who can solder two resistors to bump up the gain. I believe my stepfather can solder, so I'll wait until he wakes up before I ask him. If not, I'm sure I can find someone that can do it.

I realized the E9K has a high gain of +18db. I had thought it was 10, like the SA-31, which was why I was confused as to why it went much louder, more easily than the SA-31.

If I get this done, I'll make low gain 8-10, which would make high gain 20-22. As it stands right now, I have no use for the default low gain and have been using high gain exclusively.

To fill you guys in...





> See the photo, there are two resistors in the red panel, you don't need take off the board, just addition two 1800 ohm on the original resistors . ( each original resistor addition one 1800 ohm.).
> If you want to buy the resistors I advice you buy 1.5K, 1.8K, 2.2K ,2.7K and 3.3K for test wich is better gain for modify.
> Kingwa




I dunno what he means by addition two 1800ohm on the original resistors. I assume he means to add them directly to those resistors, and not replace them?

Edit: 



> The original resistors don't need take off just addition the new resistors on it.
> 1.5K =24DB
> 1.8K = 22DB
> 2.2K = 20DB
> ...






Awesome. My stepfather says its easy. I just have to get the resistors. The 1.8K (1800ohm) resistors should bump the low gain to 10db and high gain to 22db). That should be all the headroom I need...though I may go with the 2.2k instead. I'd use Low Gain for my ODAC and Mixamp, and High gain for my weak, portable sources).

I want to apologize. For some stupid reason, I thought the E9K's gain was lower. Even the E17 has a higher gain than the SA31. Which is why I was having issues.


----------



## Clemmaster

C/P from a PM to conquerator2:
   
   
  So I tried the cowon with the SA-31 and HE-500. As I suspected, it does not play very loud even in high gain and volume maxed out. I would say it is an average volume even for me who does not listen to crazy levels so it's a no-go (even more so with the HE-4).
   
  I think the portable amps that can drive full size headphones have much bigger gain. Paired with an IEM and its >100dB sensitivity it is never an issue but when you need to drive power hungry cans you need either a source that has line out or a bigger gain in the input stage.
   
  Some integrated amps have a MP3 input jack in the front plate and I suspect this input has an additionnal gain to it to match the other line level inputs (CD, Aux, receiver...).
   
  The thing is, if you ask Kingwa to increase the high gain to, say 25dB, you will never be able to use this gain mode with line level inputs. It can be dangerous if you accidentally swith the gain when the volume is not 0. Considering the gain button is just next to the volume one on the remote, it becomes even more dangerous. Personnaly I had the gain volume disabled on the remote, for that particular reason.
   
  With my DAC I listen to either 45-50 in gain 1 or 10- 13 in gain 2. I don't want to imagine what 45-50 in gain 2 would do to my ears (and with 10Wpc headroom it definitely will reach very high volume!).


----------



## Mad Lust Envy

Basically, what everyone needs to know about the SA-31, is that it (by default) is made for things considerably stronger than portable sources. It sounds just fine off my ODAC.

If you plan on attaching weak sources like MP3 players or your phone (i.e. 3.5mm to RCA into one of the SA-31's inputs), it will NOT drive beefier headphones to an appreciable volume.

My SA-31's rear inputs look like this...

Input 2: RCA to 3.5mm which I'd use for my phone, mp3 player, 3DS XL, PS Vita, PSP
Input 3: ODAC (sounds fantastic)
Input 4: Mixamp (for gaming in Dolby Headphone, also sounds great)

For input 3 and 4, the SA-31 is PERFECT for the DT990/600 with good headroom. High gain only needs to be between 30-50 depending on the song, etc).

Input 2: No go. Moderately low volume even with the SA-31 maxed.

So bumping the gain to at 18db-20db for high gain will benefit my 5 current portable sources, leaving low gain to be identical to what I use now for my 3rd and 4th input.

Question, the top inputs look different from the bottom ones. Are they special in any way?


----------



## Clemmaster

They are the same, Kingwa re-used the case for NFB-6 which has XLR connectors (balanced inputs/outputs) with bigger holes.
   
  Edit: the same goes for the SA-1 DAC vs. Reference 5


----------



## Mad Lust Envy

Ah ok, thanks. I didn't wanna touch the upper inputs because they didn't have the red/white markings, lol. I was like "digital coaxials?" :rolleyes:

I know it seems silly to use a desktop amp for portable gaming consoles, but I am a gamer first, audiophile second. These headphones NEED to be able to be used for those systems, so it was very important that I be able to use this amp for those sources. I wouldn't have been so vocal about the lack of gain otherwise. I know I have very peculiar needs.

I do tend to lay on my bed while playing these portable games with my good headphones. Since I've had the Fiio E9 for ages, it was never an issue. Then I swapped out temporarily for a Lyr, and then I had a problem with the NFB-5 not having analog inputs, which then I went to the E9K. I returned that which brings me to the SA-31.


----------



## tim3320070

The top inputs are higher end Neutrik RCA jacks


----------



## Mad Lust Envy

Stupid question (possibly), but wouldn't adding these resistors on top of the existing one actually LOWER volume?

This is why I stay away from the internal side of electronics.


----------



## FauDrei

Adding resistor "on top" of other resistor equals connecting them in parallel. You are actually lowering the resulting resistance, not increasing it... if this is what was bothering you.


----------



## Clemmaster

Adding a resistor in // to the existing one will decrease the equivalent resistor, so increase the gain (the volume).


----------



## Mad Lust Envy

Thanks guys.


----------



## Mad Lust Envy

Okay, new issue...minor. What resistor? 1/2 watt or 1/4 watt? The 1/8 watt was very tiny, so I doubt it was that one. Would it be one that is the same size as the one im adding it to?

I went with 2.2k ohm, for 8db low, 20 high gain.


----------



## .Sup

HE-4 works fine from the iPad albeit on max volume so I don't understand how some can experience lack of volume with those headphones. I know if I use oDac I must turn the volume way up on my amp while with AGD Ref 5 its on half the volume.


----------



## Mad Lust Envy

Before my stepfather solders, I just wanna touch base with you guys...



A crude drawing... but this would be the correct way, right?

The resistors would 'hover' over the existing resistors right? The metal legs would be directly soldered where the existing resistor's metal legs are, correct?


----------



## Clemmaster

Exactly 
   
  If you have a multimeter, try to match the 2 resistors (or you may ask your dealer, if he's nice and patient you can get a matched pair).


----------



## Mad Lust Envy

Ah damn it... now I need to get one of those.

Okay, if I get one...

I some vids, but I wanna make sure...

Certain multimeter's knob for ohm has settings at:

200M, 2M, 200K, 20K, 2K, 200

To test my 2.2Kohm at 1/4watt resistors, what setting should the multimeter be at?





I rather not bother with ANY of this, but I have no idea where to go that would do all this. I doubt the guys at Radio Shack would know what they are doing, or even have a multimeter to test this out...

My remote just stopped working, WHILE I was using it. I hope to god it's just the battery... swapped out the board on the remote (same battery), and it's still not working. Time to go to CVS...

edit: My HE-4 came in! I literally went to CVS to get new batteries as I was coming back the delivery people came behind me. I could have missed them! Wow, they are considerably light vs the HE-400...

FYI, I need the volume at around 60 vs the 40-50 mark on the DT990/600.


----------



## tim3320070

There should be an extra battery in the box.
   
  I would not get anyone's input on what you're doing other than Kingwa directly.


----------



## Mad Lust Envy

There wasn't an extra battery, though there was an extra board. Swapped the battery and it works now.

The input I'm getting is general, and not SA-31 specific. As in, testing the resistors with the multimeter. Already know what I have to do to the SA-31 itself. Just wanna make sure I get GOOD resistors. I've seen on youtube how new resistors can have wildly varying levels..., so it's a good idea to get a matched pair...


----------



## tim3320070

I just don't want you to blow-up your new (expensive) toy!


----------



## Mad Lust Envy

Trust me. I don't either, nor would I ever try that. I won't be the one touching this thing, as I do not have a delicate touch. My step father will solder the resistors, but before then, I wanna make sure the resistors are matched.

Doesn't look like I'm keeping the HE-4 anyways. Not enough bass for my needs.


----------



## Mad Lust Envy

So my stepfather soldered the 2.2K resistors in. Definitely gave it the push it needed for everything except the 3DS which is at a moderate volume with the DT990/600ohm (it was low before). At this point, I'll just call the 3DS a pathetically weak source and leave the SA-31 as is, as the Vita got plenty loud, as did my Sansa Fuze. Either I'll deal with the moderate volume, or use an easier to drive headphone later (Probably the Pro 900, if the HD650 doesn't suit my needs).

I'm more than happy with the SA-31 now. I shjouldn't have problems driving anything, with the exception of the 3DS paired with hard to drive cans which was illogical to begin with.

I don't wanna risk putting too much gain on the SA-31 just because one source wasn't a perfect match. Now, I have plenty of headroom when using my main setup.


----------



## WiR3D

Quote: 





mad lust envy said:


> So my stepfather soldered the 2.2K resistors in. Definitely gave it the push it needed for everything except the 3DS which is at a moderate volume with the DT990/600ohm (it was low before). At this point, I'll just call the 3DS a pathetically weak source and leave the SA-31 as is, as the Vita got plenty loud, as did my Sansa Fuze. Either I'll deal with the moderate volume, or use an easier to drive headphone later (Probably the Pro 900, if the HD650 doesn't suit my needs).
> I'm more than happy with the SA-31 now. I shjouldn't have problems driving anything, with the exception of the 3DS paired with hard to drive cans which was illogical to begin with.
> I don't wanna risk putting too much gain on the SA-31 just because one source wasn't a perfect match. Now, I have plenty of headroom when using my main setup.


 
  And it sounds good?


----------



## Mad Lust Envy

Sounds exactly like before. No perceived difference in noise, etc. As amazing in clarity, dynamics, and punch as before, just with a lot more volume to play with.

I just really hate the 3DS for being so pathetic in source volume. Running ampless, even the KSC35 is barely at moderate volumes with the 3DS maxed out. That's ridiculous. I'd probably need the SA-31 at like 30db to get the DT990/600 'LOUD' off it. Screw that. I'll preserve my sanity and SA-31. The 3DS is KSC35 only, I guess, unless I get the Pro 900 again. I may do that, depending on if I like the HD650 or not.


----------



## lugnut

Hello, does the SA-31 have 1 or 2 sets of RCA outputs ?  Thanks


----------



## Mad Lust Envy

Two RCA outputs. Five RCA inputs.


----------



## HaVoC-28

Quote: 





lugnut said:


> Hello, does the SA-31 have 1 or 2 sets of RCA outputs ?  Thanks


 
   
  Two RCA output , One use neutrik connector , the other  less expensive gold plated RCA (but don't mind ) .
   
  Edit : Mad Lust Envy was faster


----------



## lugnut

Great !  Thanks


----------



## Mad Lust Envy

Huh, I got my new HD650 in. So far I have used the SA-31 with:

DT990 32, 250, Pro, 600 ohms
KSC35
HE-4

The HD650 is the one where I notice the warmth jumpers making a noticeable difference. It warmed up the sound a bit too much with the HD650. I didn't notice a major change with the 990s. So since I plan on keeping those two cans as my mains, the jumpers have to stay off. If it was just the 990s, I'd keep them on.


----------



## Clemmaster

Quote: 





mad lust envy said:


> Sounds exactly like before. No perceived difference in noise, etc. As amazing in clarity, dynamics, and punch as before, just with a lot more volume to play with.
> I just really hate the 3DS for being so pathetic in source volume. Running ampless, even the KSC35 is barely at moderate volumes with the 3DS maxed out. That's ridiculous. I'd probably need the SA-31 at like 30db to get the DT990/600 'LOUD' off it. Screw that. I'll preserve my sanity and SA-31. The 3DS is KSC35 only, I guess, unless I get the Pro 900 again. I may do that, depending on if I like the HD650 or not.


 
  Why would you want Hifi headphones for 8 bits sound anyway?


----------



## Mad Lust Envy

Hey, it still sounds great. 

In the end, I took the resistors off. I decided to just stick to the KSC35 for portable use.


----------



## steve2151

Just sent in my SA-31 order today. I'll be pairing it with the matching SA-1 dac. Looking forward to hearing it in action with my HE-6.
   
  I'm hoping for a noticeable upgrade over my old NFB-10.


----------



## AManAnd88Keys

Would you guys recommend the Sa-31 for the LCD-2?


----------



## steve2151

Quote: 





amanand88keys said:


> Would you guys recommend the Sa-31 for the LCD-2?


 
   
  It's relatively neutral sounding with two levels of jumper settings to add warmth. More than enough power for any headphone (normal listening volume on my HE-6 is around 25/79 on high gain) plus it also works with sensitive iems. My old NFB-10 was a common budget recommendation for the LCD-2 and I find the SA-1/SA-31 stack to be a decent improvement if you like darker, more 3-D sound.  
   
  The D18 is a bit brighter then my SA-1, so the D18/SA-31 pairing should work for the darker LCD-2.


----------



## AManAnd88Keys

Quote: 





steve2151 said:


> It's relatively neutral sounding with two levels of jumper settings to add warmth. More than enough power for any headphone (normal listening volume on my HE-6 is around 25/79 on high gain) plus it also works with sensitive iems. My old NFB-10 was a common budget recommendation for the LCD-2 and I find the SA-1/SA-31 stack to be a decent improvement if you like darker, more 3-D sound.
> 
> The D18 is a bit brighter then my SA-1, so the D18/SA-31 pairing should work for the darker LCD-2.


 

 That's a very helpful answer, thank you! I am going to order the SA-31 soon, there's no doubt about it. I guess the sound will be a bit darker than neutral, but that's not a problem. I find synergy, tone and all that much more important than neutrality, as I leave that to studio engineers.


----------



## steve2151

Quote: 





amanand88keys said:


> That's a very helpful answer, thank you! I am going to order the SA-31 soon, there's no doubt about it. I guess the sound will be a bit darker than neutral, but that's not a problem. I find synergy, tone and all that much more important than neutrality, as I leave that to studio engineers.


 
   
  If you want to splurge, the Apex Arete might be a better match for the LCD-2 (better dynamics with a bit smaller soundstage). However, it's also $900 new with a matching $700 power supply and does not pair well with high sensitivity headphones (I get hiss on my Grados and Audio Technicas). The SA-31 on the other hand even pairs well with IEMs.


----------



## tim3320070

I don't get how a $900 amp can have any hiss, regardless of sensitivity. Zero noise should be the first priority IMO.


----------



## steve2151

Quote: 





tim3320070 said:


> I don't get how a $900 amp can have any hiss, regardless of sensitivity. Zero noise should be the first priority IMO.


 
   
  The volume range is a little limited. My HD 800 listening volume is between 9 o'clock and 11 o'clock on the dial. Anything beyond that is good for 600 ohm headphones and orthos, but there's not quite enough power for the HE-6. However, it has very, very good detail retrieval and dynamics. The Arete/SA-1 combo is one of the best solid state pairings I've heard for the HD 800.


----------



## JWahl

Quote: 





steve2151 said:


> If you want to splurge, the Apex Arete might be a better match for the LCD-2 (better dynamics with a bit smaller soundstage). However, it's also $900 new with a matching $700 power supply and does not pair well with high sensitivity headphones (I get hiss on my Grados and Audio Technicas). The SA-31 on the other hand even pairs well with IEMs.


 
   
  Do you think the SA-1/SA-31 meshes well with the Audio Technica house sound?  I'm planning on rebuilding my setup from scratch in the next few months and recently purchased an Audio Technica A900X to get a taste for the AT sound since I've never heard any before and I already am liking the basic sound signature more than my previous "flagships" (T1, HE-6, and LCD-2) and this is just running out of a laptop onboard sound.  I'll probably also upgrade to either the W3000ANV or the recently released AD2000X.
   
  I will say that I think I'm beginning to lean more towards detailed musicality vs absolute neutrality given my newfound liking of the AT sound.
   
  I noticed you only still have the AD1000PRM but would you consider it more synergistic with the SA combo or with ACSS such as the NFB-10?  Also looking at the Reference 10 all-in-one as well but it's ACSS thoughout.


----------



## steve2151

For AD1000PRM, I prefer the SA-31/SA-1 stack. The NFB-10 has a wider soundstage left to right, but the SA combo has more depth and a bit more bass quantity and extension. The -2 db treble rolloff on the SA-1 also helps a bit. 
   
  Another minor advantage that the Audio GD separates have is that the dacs have high/low gain switch that adjusts the output voltage. It's really useful for iems and sensitive headphones since it gives you a bigger usable range on the volume control.


----------



## JWahl

That's what I was hoping to hear 
	

	
	
		
		

		
			





  The SA-31/SA-2 combo is also very tempting, although an aesthetic mismatch.  Maybe they will eventually make a full size SA amp?  I'd be scared for my wallet though. I still think an SA all-in-one would be a good compromise.  I'm thinking the SA-2 would provide an even blacker background for the higher efficiency phones like the AT's
   
  I like the fact the King-Wa chose to model the diamond differential after Accuphase.  Although I don't have a lot of personal experience with their equipment, I once got a chance to listen to a setup consisting of Stax SR-007 mk1,  Blue Hawaii amp, and Accuphase DP-75 cd player.  Simply sublime combo...


----------



## elipson73

Hello,
  Do you think audio-gd sa 31 will match well with AKG K 701 ?
  Thanks


----------



## WiR3D

Quote: 





elipson73 said:


> Hello,
> Do you think audio-gd sa 31 will match well with AKG K 701 ?
> Thanks


 
  musical sound, lots of current and voltage, yes - in my uneducated opinion (having heard neither)


----------



## Mad Lust Envy

Absolutely. The AKGs should sing off the SA-31. The AKGs were brilliant off the NFB5, and the SA-31 is much more powerful, so I expect even better performance.


----------



## Clemmaster

I sold my 701's a while back but I still own the 601's (which I ended up preferring, it's more fun to listen with).
   
  I might give it a shot with the Metrum Quad + SA-31 but I don't have high expectations. I didn't listen to these since I got the HE-4s, a year and 2 months ago...
  I didn't listen to the 4's since I got the 500s, 6 months ago and I'm receiving the 400s on monday (for the fun factor).
   
  Going back to dynamics headphone will certainly hurt but if you want some inputs I could make an effort 
   
  Any particular aspect of the sound you want me to focus on?


----------



## elipson73

Hello,
  Hmm ... I don't know K 601.
  But you can do me a small review ...
  There's no serious review about audio-gd sa 31
  On the paper it seems to be a very interesting amp.
  Should be compared to Burson Soloist, Meier Classic ... with different headphones.
  Thanks.


----------



## WiR3D

Quote: 





elipson73 said:


> Hello,
> Hmm ... I don't know K 601.
> But you can do me a small review ...
> There's no serious review about audio-gd sa 31
> ...


 
  I dont think so, the Soloist is neutral if I'm not mistaken? The SA series is meant to be musical, so actually you should compare the Soloist to the other AudioGD products, from what I gather


----------



## Clemmaster

Quote: 





elipson73 said:


> Hello,
> Hmm ... I don't know K 601.
> But you can do me a small review ...
> There's no serious review about audio-gd sa 31
> ...


 
   
  The listening session did not last long, sadly...
  I see no reason for going with SA-31 vs. the cheaper Matrix M-Stage I used to pair the K-701s with.
   
  Long story short: I cannot bear the K-601s treble anymore, it seems, even with the "smooth" SA-31 (though I did not tried the SA-31 on "warm 1" and "warm 2" position). From memory, the K-701s were even more fatiguing that the 601s so for me it's a no go.
  From memory, again, I think the M-Stage (w/ OPA627) did a pretty similar job in driving the AKGs.
  I could not find any strong point in the presentation when compared to even the lesser Hifiman's planar (HE-4). On complex passages, the sound is "mid-centric", masking pretty much every side information in the sound-stage and making the whole passage, well... blurry!
   
  I think the extra power is very welcome for planar headphones (when compared with the M-Stage) but it did not add much in the 601s case.
   
  My source is a Metrum Quad, which is neutral. I don't own the warmer NFB-3.1 anymore so I cannot tame the ear-piercing/artificial treble much now...
   
  If I ever wanted to give these another chance (I'm pretty sure I never will), I would go for a tube amp  (Bottlehead crack maybe?).


----------



## conquerator2

Quote: 





clemmaster said:


> The listening session did not last long, sadly...
> I see no reason for going with SA-31 vs. the cheaper Matrix M-Stage I used to pair the K-701s with.
> 
> Long story short: I cannot bear the K-601s treble anymore, it seems, even with the "smooth" SA-31 (though I did not tried the SA-31 on "warm 1" and "warm 2" position). From memory, the K-701s were even more fatiguing that the 601s so for me it's a no go.
> ...


 
   
  Did you have a chance to try the NFB 3.1 with plannars?
  I own its latest iteration, the NFB 3.32 and am planning to use it with the HIFIman (HE-6), along with a neutral speaker amp (the Mini-X) so was wondering if you had any experience.
   
  It might not do it complete justice but it should be fine until I update my gear again 
  Thanks! Best wishes, Luke


----------



## Clemmaster

Quote: 





conquerator2 said:


> Did you have a chance to try the NFB 3.1 with plannars?
> I own its latest iteration, the NFB 3.32 and am planning to use it with the HIFIman (HE-6), along with a neutral speaker amp (the Mini-X) so was wondering if you had any experience.
> 
> It might not do it complete justice but it should be fine until I update my gear again
> Thanks! Best wishes, Luke


 
   
  Yes, my former rig used to be NFB-3.1 + M-Stage + HE-4. This was truely great back then. The sound was really intimate (which might be a downside for some music genres, e.g. classical), the background was black, which was the biggest improvement over the internal DAC of the Squeezebox Touch. The soundstage was three-dimensionnal and I could "feel" the layering in depth when I focused on it. It is less "easy" sounding as my new Metrum Quad (with which I don't need to focus at anything, it just comes at me, which is extremely relaxing yet engaging!) but it is nonetheless detailed, dynamic yet smooth!
   
  The NFB-3.1 is the reason why I keep upgrading my rig: I discovered there was so much more to get, even with as little as $300.00.
   
  Back then, I was feeding it through the coax output of my SBT. I realized lately I was missing quite a lot by doing so. The Coax output of the SBT is not that great and I got better sound through the integrated USB input (Tenor 7022L on the NFB-3.1). I always felt something was missing in the bass department, to the point I was actually thinking my DAC was faulty. I tried a XDA-1 with the same setup and it was clearly better in the bass, much better!
   
  It's only when I received my Stello U3 (USB->Coax converter) that I discovered nothing was wrong with the unit, the bass was here and hitting hard! I suppose the lack of jitter reduction mechanism in the NFB-3.1 and the poor SBT's coax output was the cause of the lack of bass. By comparison, the XDA-1 has an asynchronous SRC in the input stage which reduces jitter.
   
  Anyway, the NFB-3.32 with its good USB input should be a great improvement over the former NFB-3.1 and I would recommend it anytime for people on a budget!
   
  Note: the intimate sound I described above is due to the HE-4 (with old velour pad), not the NFB-3.1.


----------



## Mad Lust Envy

Anyone know what to set the SA-31 as a pre-amp to another amp? I assume low gain, max volume? I would prefer the SA-31 had a line out, but gotta deal with what I have.


----------



## runswithaliens

Is the display on this amp always on, or can it be dimmed and/or disabled for night time listening sessions?  If always on, how bright is it? For bright blue LEDs I would just use electrical tape, but wouldn't necessarily want to do that for the whole display if you see what I'm saying. Thanks in advance.


----------



## Clemmaster

It cannot be dimmed but it's not really bright  (At least, it never annoyed me so far).
   
  It's in my bedside rig which I use in bed, eyes closed and lights off for full immersion.


----------



## tim3320070

I use cut to fit tinted sheets found at hobby stores- it is too bright for me (not the sound though!).
   
  Some months in and this amp is wonderful- transparent, dynamic but smooth, my perfect combo.


----------



## JWahl

Just thought I'd mention that I've now had an SA-31 for about 2 weeks that I picked up from MLE.  Certainly my favorite amp I've owned so far.  I feel this is a really special amp in the current Audio-GD lineup at an excellent price/performance point.  I think a lot of people looking for a powerful single ended amp will overlook this one though, just because of the price.  I'd really be curious to hear it compared to something like the Burson Soloist, or dare I say, the Luxman amps?  I haven't heard either of them so I can't compare but I really can't imagine them being superior, maybe a different flavor.
   
  The SA-31 didn't wow me right from the get go, but over time I've come to enjoy it more and more.  I find the strongest trait of the diamond differential topology to be the sense of space and depth that it draws from recordings.  It's too bad I don't still have my SA-1 DAC to try with it though.  I'm currently using a Schiit Modi as a budget fix for the time being.  I'm considering buying an Audio-GD NFB-2.32 to pair with it since it's not too expensive.  
   
  I'm also currently using AKG K702 65th anniversaries and Audio Technica A900X but I'm toying with the idea of buying an HE-6 once again or maybe HE-500.  I think the SA-31 could drive the HE-6 well and would complement the signature, though I may have the add the resistor mod MLE had done before to increase the gain to HE-6 levels.  I'll see how it is once I get a new DAC.  I'm very curious to see how it well scale up with better source and headphones.
   
  One thing that is completely unique to the SA-31 from other Audio GD headphone products that nobody seems to have pointed out is the 4 Massive output transistors that seem to be similar or the same as used in their larger speaker amps.  I'm assuming this is to help drive the more difficult planars like the HE-6 given everyone seems to say they sound best on a speaker amp.  The 8w @ 50 ohms of the SA-31 would be about equivalent to 50w @ 8 ohms in a speaker amp.
   

  Master 3 Speaker Amp
   

  SA-31


----------



## WiR3D

Quote: 





jwahl said:


> The 8w @ 50 ohms of the SA-31 would be about equivalent to 50w @ 8 ohms in a speaker amp.


 
  Not quite.
   
  Something I am curious of, how coloured is the sound on this amp?


----------



## FauDrei

I am joining in praise of this headamp.
   
  It took some time to "open", "burn-in", "form capacitors" or whatever you want to call it, but at the present state of it - I prefer it in it's "plain" single ended RCA "voltage" mode to the "neutrality" of my full differential ACSS "current" mode headamp. It is so detailed, clear, "spacious", dynamic and "rich". Very seductive.
   
  It is excellent with HE-500. SA-31 was the factor that tipped my preference scale from LCD-2 (V1) in HE-500 direction. It forces you to search for better aftermarket cable for them though. But HE-500 deserve better OCC cable (and better connectors) and this headamp unequivocally presents the difference.
   
  ...as for output transistors - they are not "the King of transistors" On Semiconductors MJL4281/4302  as in A-GD Master series poweramps. They are Toshiba power counterparts and the Man says this on the topic:
   
  Quote: 





> The On Semiconductors MJL4281/4302 sound is detail and dynamic, which is neutral sound but for the SA31, we want warmer and thick sound so the Toshiba sound is match in my mind.
> Kingwa


----------



## WiR3D

Quote: 





faudrei said:


> I am joining in praise of this headamp.
> 
> It took some time to "open", "burn-in", "form capacitors" or whatever you want to call it, but at the present state of it - I prefer it in it's "plain" single ended RCA "voltage" mode to the "neutrality" of my full differential ACSS "current" mode headamp. It is so detailed, clear, "spacious", dynamic and "rich". Very seductive.
> 
> ...


 
  I keep getting the impression that this is an amp for low impedance headphones that need some juice and you want to add some colour - AKG's, low impedance planers, most probably Grado.
   
  Not for already coloured headphones like the Denon D7000.


----------



## tim3320070

This is AGD colored, as in very slight warmth. This is 95% neutral to my ears. Plus you can dial in the "warmth" with those jumpers. It's all pretty subtle. It's an excellent amp.


----------



## WiR3D

Quote: 





tim3320070 said:


> This is AGD colored, as in very slight warmth. This is 95% neutral to my ears. Plus you can dial in the "warmth" with those jumpers. It's all pretty subtle. It's an excellent amp.


 
  Now even more curious to hear impressions with Denons.


----------



## JWahl

Quote: 





wir3d said:


> Not quite.


 
   
  That was mostly a rough estimation of what the power would be at 8 ohms in comparison to people who use speaker amps to power the HE-6.  I understand that the SA-31 wouldn't be able to do that with speakers due the current demands of speaker level impedances.
   
  Quote: 





wir3d said:


> I keep getting the impression that this is an amp for low impedance headphones that need some juice and you want to add some colour - AKG's, low impedance planers, most probably Grado.
> 
> Not for already coloured headphones like the Denon D7000.


 
   
  These are probably the most obvious candidates for the SA-31 but I wouldn't say it's less optimal at higher impedances.  Only issue I would imagine is with stock gain with a low voltage source, but this can be easily modified by soldering 2 resistors if your comfortable with that.  I can't say with the D7000 as I've never heard them but I used to own the R1 LCD-2 which is very dark and I think it would probably sound decent on the SA-31 but I certainly don't think it would add any additional sparkle to them.
   
  Quote: 





faudrei said:


> ...as for output transistors - they are not "the King of transistors" On Semiconductors MJL4281/4302  as in A-GD Master series poweramps. They are Toshiba power counterparts and the Man says this on the topic:


 
   
  Ah, yes.  I noticed that a little later.  Either way, I still find it interesting that it uses a speaker style output transistor.  That MJ4281/4302 transistor is listed as a Bipolar transistor on it's datasheet.  If I had to guess, I'd say the Toshibas in the SA-31 are probably MOSFETs given they are known for a warmer sound and the Accuphase that it's supposed to be modeled after uses a MOSFET output stage.
   
  Quote: 





tim3320070 said:


> This is AGD colored, as in very slight warmth. This is 95% neutral to my ears. Plus you can dial in the "warmth" with those jumpers. It's all pretty subtle. It's an excellent amp.


 
   
  I'd have to agree with this.  I find it warm only in the sense that it doesn't exaggerate source material that is already borderline bright.  It's certainly not colored enough to paint a magical illusion over poorly recorded material.  As Faudrei mentioned in his review, I find the "coloration" to be in the area of harmonics, not frequency response. It could be that the topology of the amp is engineered to retain certain small amounts of the "euphonic" harmonic distortion, similar to tube amps, but in smaller amounts and not affecting clarity and black background like some tubes might.  Though it is a pleasant coloration to me, and doesn't detract from the clarity or detail of the amp.  I'm very hesitant to say it sounds like tubes because it doesn't necessarily, and "tube coloration" already conjures up certain preconceptions that I don't think apply to this amp.  
   
  Also, the exceptional sense of space and depth in the soundstage could be taken by some to be larger than life and be considered a coloration.  When I first got the amp, I thought it was really laid back but after further listening I realized this was simply a product of it's increased soundstage and was still fully capable of an intimate sound when the recording calls for it with plenty of impact when called upon.  One thing I want to emphasize is that this is in no way a slow or sluggish sounding amp.  I think what is so "seductive" is the non-fatiguing presentation combined with a sense of speed and clarity normally only reserved for more ruthlessly neutral amps.  Almost similar to how an LCD-2 can be both warm and fast at the same time.


----------



## tim3320070

Quote: 





jwahl said:


> Also, the exceptional sense of space and depth in the soundstage could be taken by some to be larger than life and be considered a coloration.  When I first got the amp, I thought it was really laid back but after further listening I realized this was simply a product of it's increased soundstage and was still fully capable of an intimate sound when the recording calls for it with plenty of impact when called upon.  One thing I want to emphasize is that this is in no way a slow or sluggish sounding amp.  I think what is so "seductive" is the non-fatiguing presentation combined with a sense of speed and clarity normally only reserved for more ruthlessly neutral amps.  Almost similar to how an LCD-2 can be both warm and fast at the same time.


 
  This I have found to be true of all the gear I have from Kingwa, from the Master-5 down to the NFB-16. It's why I buy his amps and dac's.


----------



## JWahl

Quote: 





tim3320070 said:


> This I have found to be true of all the gear I have from Kingwa, from the Master-5 down to the NFB-16. It's why I buy his amps and dac's.


 
  That's true.  I just find it more dramatic with SA series than the ACSS.  I've only previously the SA-1 DAC and NFB-1ES (old style).  I was actually looking at your Ref 8 for sale with my upcoming tax return but I really want to pick up an HE-6 again so it's only one or the other for my budget at the moment.  Considering NFB-2.32 to pair with instead.  The Modi i'm using now is decent for the money but I need a better source to do this amp justice.


----------



## WiR3D

Quote: 





jwahl said:


> I'd have to agree with this.  I find it warm only in the sense that it doesn't exaggerate source material that is already borderline bright.  It's certainly not colored enough to paint a magical illusion over poorly recorded material.  As Faudrei mentioned in his review, I find the "coloration" to be in the area of harmonics, not frequency response. It could be that the topology of the amp is engineered to retain certain small amounts of the "euphonic" harmonic distortion, similar to tube amps, but in smaller amounts and not affecting clarity and black background like some tubes might.  Though it is a pleasant coloration to me, and doesn't detract from the clarity or detail of the amp.  I'm very hesitant to say it sounds like tubes because it doesn't necessarily, and "tube coloration" already conjures up certain preconceptions that I don't think apply to this amp.
> 
> Also, the exceptional sense of space and depth in the soundstage could be taken by some to be larger than life and be considered a coloration.  When I first got the amp, I thought it was really laid back but after further listening I realized this was simply a product of it's increased soundstage and was still fully capable of an intimate sound when the recording calls for it with plenty of impact when called upon.  One thing I want to emphasize is that this is in no way a slow or sluggish sounding amp.  I think what is so "seductive" is the non-fatiguing presentation combined with a sense of speed and clarity normally only reserved for more ruthlessly neutral amps.  Almost similar to how an LCD-2 can be both warm and fast at the same time.


 
  Aha well when I was talking colouration, I was quite vague, but you did answer my question. 
   
  Specicifically for the Denons:
  Non emphasized smooth treble: check.
  Neutral FR: check.
  High PRaT:check (if its slow then it overslows the already somewhat slow Denons)
   
  and finally
  Not adding harmonics: Not check. But this can be broken - case and point WA6SE and EC Zana Duex SE. But it has to be done right, otherwise the music becomes syrupy. I'm gonna guess its subtle. 
   
  Even more curious to try it now.


----------



## Clemmaster

Just a quick post to say that technically, it's on par with the integrated amp of my NFB-27 in balanced mode. This was not expected.
   
  I was already amazed by the size of the soundstage and the bass slam it put on my face (coming from a M-Stage with HE-500)! I though that going balanced would even increase these technicalities (that's what I read a lot of time, especially on the NFB-10SE thread) but that's clearly not the case.
   
  The only difference I can notice is a change in signature (to the benefit of the SA-31 in my case). The added harmonics are never too much and they simply grow on me! It makes the music both relaxing and engaging, which, in my book, is quite a feat. The Metrum Quad is the other gear that also achieves that...
   
  The bass might also be a tiny bit (and I mean tiny) loosen, which I also appreciate. Don't get me wrong, the bass is very tight (when associated with the NFB-27 as a DAC), much more than with the Metrum Quad. That might just be the overall warmer voicing that gives me that impression.
   
  As for the level of warmth it exhibit, I would say that with the max warmth setting (2 jumpers), it's not warmer than the M-Stage (from memory, I did not compare them side by side, though I could, since I still have the matrix).
   
  Bottom line: an excellent amp to pair with the sometimes bright Hifiman planars!


----------



## runswithaliens

Quote: 





wir3d said:


> I keep getting the impression that this is an amp for low impedance headphones that need some juice and you want to add some colour - AKG's, low impedance planers, most probably Grado.
> 
> Not for already coloured headphones like the Denon D7000.


 
   
  Rated output specs:
  [size=x-small]10000 MW /  40 ohm

 8000 MW /  50 ohm

  4000 MW  /  100 ohm

 1400 MW / 300 ohm

 700 MW / 600 ohm[/size]
   
  [size=x-small]So, as far as driving higher impedance headphones like the Senn HD6[size=x-small]50s, it is p[/size]utting out 1.4 watts into 300 Ohms w[size=x-small]hich[/size] [size=x-small]translate to 20 Volts... that[size=x-small]'[/size]s right up there with OT[size=x-small]L t[/size]ube amps power isn't it?[/size][/size]  But then the OTL amp wouldn't be able to put nearly so much juice into the lower impedance headphones.  Seems like you are getting the best of both worlds here?


----------



## WiR3D

Quote: 





runswithaliens said:


> Rated output specs:
> [size=x-small]10000 MW /  40 ohm
> 
> 8000 MW /  50 ohm
> ...


 
  edit - i was being a tard and BTW its mW not MW - thats substation level power
   
   
  insert Nazism


----------



## bsoontan

Quick question, which would be better for the SA-31 silver RCAs or copper RCAs?


----------



## WiR3D

Quote: 





bsoontan said:


> Quick question, which would be better for the SA-31 silver RCAs or copper RCAs?


 
  Cryo butterfly fart RCA


----------



## AManAnd88Keys

Quote: 





bsoontan said:


> Quick question, which would be better for the SA-31 silver RCAs or copper RCAs?


 

 I can't answer this question, as there are way to many different kinds of RCA cables! There are awesome copper interconnects AND awesome silver interconnects AND awesome SPC interconnects AND awesome Silver/Gold interconnects, so I'd say you should tell us which are the RCAs you are interested in?


----------



## bsoontan

Quote: 





amanand88keys said:


> I can't answer this question, as there are way to many different kinds of RCA cables! There are awesome copper interconnects AND awesome silver interconnects AND awesome SPC interconnects AND awesome Silver/Gold interconnects, so I'd say you should tell us which are the RCAs you are interested in?


 

 I suppose what I want to know is if getting a decent RCA cable is worth it compared to say a normal cheap RCA cable. ie. $5 cable vs. $50 cable.


----------



## conquerator2

jwahl said:


> That's true.  I just find it more dramatic with SA series than the ACSS.  I've only previously the SA-1 DAC and NFB-1ES (old style).  I was actually looking at your Ref 8 for sale with my upcoming tax return but I really want to pick up an HE-6 again so it's only one or the other for my budget at the moment.  Considering NFB-2.32 to pair with instead.  The Modi i'm using now is decent for the money but I need a better source to do this amp justice.




I can recommend it!
Pairs really well with the HE-6 (along with the Mini-X)
Very neutral yet very slightly warm which helps the HE-6 slightly accentuated treble as it never sounds harsh with recordings.


----------



## AManAnd88Keys

Quote: 





bsoontan said:


> I suppose what I want to know is if getting a decent RCA cable is worth it compared to say a normal cheap RCA cable. ie. $5 cable vs. $50 cable.


 

 Oh boy, that's a discussion I don't want to start. I for one use higher quality cable and think that it is definitely worth it to spend quite some money on good interconnects if you are about to get a nice amp. But others would probably call me crazy and all that, so don't take my word for it. There's a kind of pro and anti-cable war that never seems to end...


----------



## WiR3D

Quote: 





bsoontan said:


> I suppose what I want to know is if getting a decent RCA cable is worth it compared to say a normal cheap RCA cable. ie. $5 cable vs. $50 cable.


 
  You know - some claim its pointless, some claim its a big factor.
  
  I for one, Think anything that meets a decent line of specifications (for interconnects) is perfect. QED Audio 2 cables, thats where I stop. Lifetime warranty, good quality, not expensive. 
   
  As for speaker cables - lamp wire or anything that can carry a lot of current and isn't corroded or going past a massive source of noise.
   
  Or Coax cable - little more difficult to work with, but if the entire television industry runs off it, then why the hell not.


----------



## bsoontan

Quote: 





wir3d said:


> You know - some claim its pointless, some claim its a big factor.
> 
> I for one, Think anything that meets a decent line of specifications (for interconnects) is perfect. QED Audio 2 cables, thats where I stop. Lifetime warranty, good quality, not expensive.
> 
> ...


 

 Ah, the answer I was looking for. Thank you.


----------



## tim3320070

Quote: 





bsoontan said:


> I suppose what I want to know is if getting a decent RCA cable is worth it compared to say a normal cheap RCA cable. ie. $5 cable vs. $50 cable.


 
  Well, let me state that I have a Master-5/ Ref-8 using Monoprice power cables and interconnects- you judge where I place my importance.


----------



## AManAnd88Keys

Quote: 





tim3320070 said:


> Well, let me state that I have a Master-5/ Ref-8 using Monoprice power cables and interconnects- you judge where I place my importance.


 

 You mean Reference 5 + Master 8? How does the SA-31 fare against the Master 8?


----------



## Clemmaster

No he means Reference 8 (balanced SA DAC) and Master 5 (predecessor to Master 8).
   
  The internal amp in the 3x r-core DAC/amp (Reference 10, NFB-20, NFB-27) is said to be on par with that of the Master series (though one can question this claim).
  As I wrote few posts before, the SA-31 is technically on par with the internal amp of my NFB-27.
   
  To these technicalities, it adds the "musical flavor" and a warmer tone (when set accordingly, using the 2 jumpers) which make me prefer it over the NFB-27.


----------



## AManAnd88Keys

Quote: 





clemmaster said:


> No he means Reference 8 (balanced SA DAC) and Master 5 (predecessor to Master 8).
> 
> The internal amp in the 3x r-core DAC/amp (Reference 10, NFB-20, NFB-27) is said to be on par with that of the Master series (though one can question this claim).
> As I wrote few posts before, the SA-31 is technically on par with the internal amp of my NFB-27.
> ...


 

 That's helpful, thank you!


----------



## xiaobao0707

Anyone has tried the SA-31 with HD800? from what I read here, the "warm yet detailed" nature of SA-31 should suit greatly with HD800. But I will be more than happy to have your opinion.
   
  It's a shame that no shipment is possible during Chinese new year tho... 
   
  Thanks.


----------



## steve2151

I'll do some A/Bing later. Arete/Volcano is usually my go to amp for the HD 800 and other high impedance headphones, but I'll see how the Audio GD compares.


----------



## xiaobao0707

Quote: 





steve2151 said:


> I'll do some A/Bing later. Arete/Volcano is usually my go to amp for the HD 800 and other high impedance headphones, but I'll see how the Audio GD compares.


 
  thanks very much, will be happy to have your opinion on the comparison.


----------



## steve2151

The SA-31 is airier and has a softer treble. The Arete/Volcano stack has a blacker background and brings the mids and bass forward. 
   
  I think the Arete compliments the HD 800 better, since it can sound too distant on some tracks. Although there is more space on the SA-31, this sometimes causes the mids and bass to feel recessed on some tracks. Despite the smaller soundstage, the Arete actually has better instrument separation due to the blacker background and better microdetails. 
   
  I give a slight advantage to the Arete /Volcano, but I'd quantify it as a 10% improvement for 3 times the money. 
   
  On the flip side, the SA-31 sounds marvelous with the HE-6 since the ortho is less grainy and has what I consider to be a better frequency balance to begin with. The Arete doesn't supply enough power for the HE-6 and that combo sounds like listening to a concert in a subway tunnel - the soundstage is compressed horizontally and highs sound excessively sharp.


----------



## zenpunk

Really considering this for my HE-6...looks like the ideal poor man EF-6


----------



## Utopia

I got mine a couple of days ago. 
	

	
	
		
		

		
		
	


	




  Still early with the burn-in - the first couple of hours it was far from warm or musical, but even after only 24 hours it's starting to open up. This is my first Audio GD amp, and I've understood that they need quite a bit of time to get into shape.
   
  Anyway, it's definitely more detailed and spacious-sounding than my previous Matrix M-Stage (a lovely amp - hope I won't miss it). I'm running it with AKG K702 Anniversaries and Denon AH-D5000 (which only gives me maybe ten usable steps on the volume control...), but plan on getting either T1 or HE500 soon to go with it.
   
  For now I'm planning to burn it in for another few days, and then try out the different jumper settings.


----------



## AManAnd88Keys

Quote: 





utopia said:


> I got mine a couple of days ago.
> 
> 
> 
> ...


 
  I am looking forward to more impressions


----------



## JWahl

Quote: 





utopia said:


> I got mine a couple of days ago.
> 
> 
> 
> ...


 
  I'm also using the SA-31 with the K702 65th, as well as my AD2000X with good results.  Hoping to pick up an HD-800 in the next few weeks that I can compare as well.  It does seem to scale well with source also.  Unfortunately I haven't got to try the jumper setting since I bought mine used and it didn't ship with the jumpers.  I noticed a nice upgrade from the Schiit Modi to Resonessence Concero, even though both are simple, USB powered DACs.


----------



## tim3320070

I'll say it again that this amp is only slightly left of neutral. It's warm in relation to other AGD amps only.


----------



## Clemmaster

Quote: 





tim3320070 said:


> I'll say it again that this amp is only slightly left of neutral. It's warm in relation to other AGD amps only.


 
   
  Yep.
   
  The m-stage is warmer than the SA-31 on its default state (no jumpers).
  Adding the 2 jumpers makes it closer to the m-stage but I wouldn't call it warmer, even.
   
  The m-stage is a really good amp by itself (an cheap at that). Paired with planars, the SA-31 is the real deal!
  The big soundstage is great addition to headphones that don't particularly shine in this area (planars, again).


----------



## AManAnd88Keys

Quote: 





clemmaster said:


> Yep.
> 
> The m-stage is warmer than the SA-31 on its default state (no jumpers).
> Adding the 2 jumpers makes it closer to the m-stage but I wouldn't call it warmer, even.
> ...


 
  That's why I think the SA-31 will be the real deal for my LCD-2s


----------



## AManAnd88Keys

Is anyone here who owns or has heard both the SA-31 and the Yulong A18? A comparison would be great.


----------



## oqvist

Quote: 





jwahl said:


> That was mostly a rough estimation of what the power would be at 8 ohms in comparison to people who use speaker amps to power the HE-6.  I understand that the SA-31 wouldn't be able to do that with speakers due the current demands of speaker level impedances.
> 
> 
> These are probably the most obvious candidates for the SA-31 but I wouldn't say it's less optimal at higher impedances.  Only issue I would imagine is with stock gain with a low voltage source, but this can be easily modified by soldering 2 resistors if your comfortable with that.  I can't say with the D7000 as I've never heard them but I used to own the R1 LCD-2 which is very dark and I think it would probably sound decent on the SA-31 but I certainly don't think it would add any additional sparkle to them.
> ...


 
  This description somehow feels accurate for the C-2.1 every bit of it. I have compared it to the Goldpoint Heapdhone Pro. They are a hair a hair brighter and particularly the Ear One you can´t possible get more drive. 3W at 32 ohm more then enough for my LCD-2. I feel the C-2.1 have plenty too but still a bit bummed Kingwa never mentioned the C-2.2 to me lol. But more W more noise perhaps who knows 
   
  I am kind of curious what signature the SA-31 has in comparison. I have the Audio GDF Ref9 and the NFB10SE. Would it be something similar? Ref9 is in the musical series with the diamond buffer setup and NFB10SE supposed to be neutral.


----------



## tim3320070

The Ref-9 is perfect for the SA-31. His SA-2 dac is the upgraded Ref-9.


----------



## oqvist

Perhaps. Or it´s cake on cake


----------



## Mad Lust Envy

jwahl said:


> I'm also using the SA-31 with the K702 65th, as well as my AD2000X with good results.  Hoping to pick up an HD-800 in the next few weeks that I can compare as well.  It does seem to scale well with source also.  Unfortunately I haven't got to try the jumper setting since I bought mine used and it didn't ship with the jumpers.  I noticed a nice upgrade from the Schiit Modi to Resonessence Concero, even though both are simple, USB powered DACs.




I'm 100% positive I put a small bag with the jumper chips in there. You may have tossed it unknowingly. 

It was pretty small.


----------



## JWahl

Quote: 





mad lust envy said:


> I'm 100% positive I put a small bag with the jumper chips in there. You may have tossed it unknowingly.
> 
> 
> 
> ...


 
  That's very possible, I've been meaning to ask you if you did.  I just assumed not.  I thought maybe I still had some leftover from my old SA-1 but I couldn't find them.  I'll probably see if I can find some online sometime.  They seem to just be generic jumpers like ones from old computer motherboards.


----------



## Mad Lust Envy

Yeah, if you have a local Radio Shack, im sure they're incredibly cheap. I have some more that came with my Compass 2, so if you want, I can send some to you in an envelope.


----------



## JWahl

Quote: 





mad lust envy said:


> Yeah, if you have a local Radio Shack, im sure they're incredibly cheap. I have some more that came with my Compass 2, so if you want, I can send some to you in an envelope.


 
  I'll check there sometime and give an update.  If they carry them that might be useful information for other Audio-GD users that need jumpers.


----------



## Utopia

I wonder what volume settings people are using with this amp? Obviously it's very powerful, but with my K702 Anniversaries I stay around 10/79 on low gain with my Essence ST as a source. Trying with my mobile phone, an HTC One X, I went to maybe 30/79 on low gain. It just seems to have a fairly high gain (unlike what I've been reading here). I just hope mine is ok!


----------



## JWahl

Quote: 





utopia said:


> I wonder what volume settings people are using with this amp? Obviously it's very powerful, but with my K702 Anniversaries I stay around 10/79 on low gain with my Essence ST as a source. Trying with my mobile phone, an HTC One X, I went to maybe 30/79 on low gain. It just seems to have a fairly high gain (unlike what I've been reading here). I just hope mine is ok!


 
  Hmmm that's very strange indeed.  Especially since I have the HTC One X and know just how poorly low the output level it has.  I just sold my K702 65th Anni but when I used them with the SA-31 on a 1.2v source, My average range was 50-70 on high gain.  I think there is one of two possibilities.  If you bought the SA-31 pre-owned, the previous owner may have done the resistor mod to increase gain by soldering 2 lower resistance resistors on top of 2 particular existing ones.  
   
  The other would be if your using a y-cable out of the headphone out of the Essence ST or it uses more than 2v output at RCA.  But that wouldn't explain the mobile device.  That's my normal listening level with my highly efficient AD2000X.  The stock gain level on low is literally no gain (0db) and 10db on High gain.  The resistor mod increases both the low and high gain levels.  The only other thing if you didn't buy used is maybe they accidently installed the wrong value resistors in those particular spots.


----------



## Utopia

Thanks, JWahl! I will try it with different sources and see how it goes. I does seem to have very high gain, though, compared to other SA-31s, but I can't imagine what could cause that. It's brand new from Audio GD. I've been in touch with Kingwa, and apparently it's possible to get a volume board with lower gain for $15, which is very good to know. But first I just want to be sure there's nothing strange going on with it.


----------



## Mad Lust Envy

The K702 Annie is pretty easy to make loud. Try something like the HE-4, the standard setup with a 2v source needed high gain on like 70 volume. For an amp of this much power, I expected the gain to be on par with it's power, which it wasn't, IMHO.


----------



## Utopia

I think this all makes more sense now. Because it was so loud already on low gain I didn't go much above the first ten steps or so on the volume control, and thought the rest of the range would be really extreme (not to mention high gain). Now I've tried some different sources (all pretty bad, phones, laptops) and played with the volume control on those, and now I can see that the rest of the volume range on the SA-31 isn't as extreme as I first thought. The difference between high gain and low gain isn't very large either. Those 10 dB for me translate to 6/79 on low gain being equal to 1/79 on high gain, more or less.
   
  So, now I'm ready to enjoy the amp fully without worrying. It really is a step above the M-Stage, as it should be, and as reported it's not quite as warm even with two jumpers. To me it seems very detailed, dynamic, spacious, dark in some sense - if the M-Stage was a warm and comfy chic-flick this feels more like The Dark Knight Rises.


----------



## steve2151

Quote: 





jwahl said:


> Hmmm that's very strange indeed.  Especially since I have the HTC One X and know just how poorly low the output level it has.  I just sold my K702 65th Anni but when I used them with the SA-31 on a 1.2v source, My average range was 50-70 on high gain.  I think there is one of two possibilities.  If you bought the SA-31 pre-owned, the previous owner may have done the resistor mod to increase gain by soldering 2 lower resistance resistors on top of 2 particular existing ones.
> 
> The other would be if your using a y-cable out of the headphone out of the Essence ST or it uses more than 2v output at RCA.  But that wouldn't explain the mobile device.  That's my normal listening level with my highly efficient AD2000X.  The stock gain level on low is literally no gain (0db) and 10db on High gain.  The resistor mod increases both the low and high gain levels.  The only other thing if you didn't buy used is maybe they accidently installed the wrong value resistors in those particular spots.


 
   
  Audio GD dacs usually have 2.5 V output on high gain and 1.25 V on low gain. I normally use the HE-6 at 35 on high gain with the SA-1 also on high gain. My AD1000PRM is normally around 20 on low gain with the SA-1 also set to low gain.


----------



## JWahl

Quote: 





steve2151 said:


> Audio GD dacs usually have 2.5 V output on high gain and 1.25 V on low gain. *I normally use the HE-6 at 35 on high gain with the SA-1 also on high gain*. My AD1000PRM is normally around 20 on low gain with the SA-1 also set to low gain.


 
   
  That's actually lower than I would have expected given the sensitivity of the HE-6.  I did figure the gain settings were designed more to fit with the slightly higher output of their DACs.  Their DACs that don't have a high/low switch is also 2.5v.  I would be curious to try my old SA-1 with my current setup now but I'm surprisingly satisfied with my current setup.  I also finally have an HD-800 on the way.  Should be here tomorrow.  I think with only one SA component upstream, maybe the soundstage won't be too overly distant but then again, Sabre based DACs are also known for their wide soundstage.


----------



## Utopia

I'm looking to upgrade my DAC as well (from the Essence ST), and both the Audio GD NFB.1.32 and the Concero look like very good choices with the SA-31. The NFB 1.32 has the high/low gain just like the SA-1, and the Concero has the 1.2 V output. They're also both very detailed, as far as I've understood, which should work well with the SA-31 and its warmth/musicality settings.


----------



## Clemmaster

@Steve2151, JWahl: could you please give some inputs on the SA-1 DAC.
  I see that you (JWahl) have the Concero too. I have my eyes on this little gem right now and would like to know:
    1) How it compares to the SA-1, technically (I suppose the SA-1 is a more mature DAC, technically)
    2) How is the tonal voicing compared to the others DAC you heard/own.
   
  Any input on the SA-1 in general (technically, voicing) would be highly appreciated!
   
  For the record:
  I own the HE-4 and HE-5LE now.
   
  I used to own the Ref 5.32 (too dark) and now the NFB-27 (really good but I prefer(ed) my SA-31 over its internal amp w/ the HE-500 & HE-4. I just received the HE-5LE today but didn't get a listen, the internal amp might be a better fit for them).
   
  So far, the most enjoyable DAC was the Metrum Quad. It's a mix between the 2 with a voicing closer to the NFB-27 but more relaxed in the bass (less "tension" in the sound). I sold my Stello U3 recently and am planning to buy another DDC for it.
  So far, I'm torn between a custom DI-V3 + DSP or the Concero, which both feature resampling. The concero would be (much) more convenient to use, but it's 2x as expensive as the DI + PSU. If the DAC is any good (by NFB-2 or Bifrost standart), it might be a viable solution.


----------



## JWahl

Quote: 





utopia said:


> I'm looking to upgrade my DAC as well (from the Essence ST), and both the Audio GD NFB.1.32 and the Concero look like very good choices with the SA-31. The NFB 1.32 has the high/low gain just like the SA-1, and the Concero has the 1.2 V output. They're also both very detailed, as far as I've understood, which should work well with the SA-31 and its warmth/musicality settings.


 
   
  The NFB-1.32 is an obvious choice if you want to maintain Aesthetic integrity and have a nice stack.  If you want to save money I wouldn't rule out the NFB-2.32 as well.  Especially if your only using the SA-31.  I'm using the Concero now with good results.  I especially like the filter options and being able to use it as a USB/SPDIF converter while keeping the inline filters to the main DAC.  Or, if your willing to spend a bit more the new Matrix X-Sabre shows potential to be a promising unit at $1100 from what I've read.
   
  Quote: 





clemmaster said:


> @Steve2151, JWahl: could you please give some inputs on the SA-1 DAC.
> I see that you (JWahl) have the Concero too. I have my eyes on this little gem right now and would like to know:
> 1) How it compares to the SA-1, technically (I suppose the SA-1 is a more mature DAC, technically)
> 2) How is the tonal voicing compared to the others DAC you heard/own.
> ...


 
   
  Unfortunately, I can't really accurately compare the SA-1 and Concero as when I owned the SA-1 I had completely different amps and headphones than I have now.  I will say the I currently feel no upgraditis for a DAC at the moment but if I do, it's nice that I can keep the Concero as a converter with the excellent Resonessence upsampling filters.  Without sounding cliche, I would say the Concero has a very neutral balance without being aggressive or fatiguing in anyway on it's own.  The Schiit Modi by comparison is rather aggressive and less realistic but it's also 1/6th of the price.
   
  Being an Audio-GD fan, I'm generally a subscriber to the old school all-discrete/overbuilt power supply type of gear but, even though opposite design philosophy, the Concero doesn't disappoint.  And also, I haven't heard the Bifrost but every impression I've read of people who compared the Concero to it have said they thought the Concero was clearly superior.
   
  Also, I just got my HD-800 today and listening to right now as I type.  Even though only listening for a bit, I think it's safe to say the SA-31 drives it well.  Granted, I don't have much of a frame of reference and maybe other amps put it into a whole new class but it certainly doesn't feel like it's under driven.  It's super dynamic, spacious, excellent timing, and IMO probably the best quality bass I've heard an any headphone I've owned.  I'm shocked that some people consider it bass light.
   
  These are early impressions so take it with a grain of salt.  To be fair though, I used the JRiver parametric EQ to cut the 6kz area by 6db due to pretty heavy sibilance but it sounds much smoother now.  Maybe I'll try the Anaxilus Mod later on.


----------



## JWahl

I've got some jumpers and playing around with the warmth settings.  I do like the "Warm 2" setting with the HD-800 as an easy listen but I'm still deciding if I want to keep them on as it does seem to trade a little precision and detail for smoothness, but it does also tame the sibilance enough to where I can use them without my slight sofware EQ.  
   
  Also seems to have a little more bass quantity but maybe a bit too much bloom on certain tracks.  I just wish the warmth settings were tied to a front panel switch instead of jumpers.  Makes it harder to A/B them.
   
  *edit* I went back to "Warm 1" jumper setting and I find it warm enough without sacrificing the precision/detail.  I briefly tried it yesterday and skipped it because I thought it sounded odd.  Maybe I didn't have one of the jumpers pressed down all the way, or something was messing with my hearing because it sounds fine now.  No jumpers almost sounds a little flat by comparison, but I don't want to exaggerate the difference, it's very subtle.


----------



## steve2151

Quote: 





clemmaster said:


> @Steve2151, JWahl: could you please give some inputs on the SA-1 DAC.
> I see that you (JWahl) have the Concero too. I have my eyes on this little gem right now and would like to know:
> 1) How it compares to the SA-1, technically (I suppose the SA-1 is a more mature DAC, technically)
> 2) How is the tonal voicing compared to the others DAC you heard/own.
> ...


 
   
  The dac in the SA-1 is more spacious and darker than the dac in my NFB-10. It's on another level entirely when compared to the dac section of the NFB-12 or HUD-MX1, which I used in place of the SA-1 while packing for a move.
   
  It's close enough to neutral that my SA-31 and Arete color the sound more than the dac itself.


----------



## Utopia

I've had my SA-31 for a few weeks now and I'm very happy with it. It drives HE-500 effortlessly, and makes Denons just a little bit more balanced, with more control of both bass and treble, IMO. I'm still getting used to the volume buttons, but I think they are ok. It would be great to see that solution put to better use, for instance to have a memory for different volume settings for different headphones - something to add extra value over a regular volume knob.  Either way, overall I'm very happy with the amp.
   
  I just wonder how far it scales? I haven't seen any reviews really where it's compared to other amps in the $500-700 range, like Schiit Lyr or even the V200 (more expensive). It seems that the SA-31 is tailored for headphones like the HE-6 or even K1000, but would it really do them justice?


----------



## Utopia

Running my SA-31 with Beyerdynamic T1 now  - I have it for a week to try out 
	

	
	
		
		

		
			




   
  I've only heard the T1 with the A1 amp and I do prefer the SA-31 quite a lot. The A1 is extremely detailed, and it has a lovely volume pot (the whole case looks flimsy to me, like an old router, but it feels very solid). The SA-31 on the other hand is definitely warmer, more musical and engaging. Currently I'm using warm setting 2, which I haven't found useful before, but the T1s are bright headphones - certainly compared to the HE-500, IMHO. Still have more listening to do, but the SA-31 + T1 seem like a great combination. Listening to everything from Guns n' Roses' Appetite for Destruction to Sara Sant'Ambrogio's The Chopin Collection with it, and it's got both warmth, speed, and detail.


----------



## bishyb

A question about this amp (sorry if this has been asked/answered already):
   
  - Can you control the volume of the rca outputs using the internal volume controls?  Would like to output the rca to a set of studio monitors and control the volume via the headphone amp if possible.
   
  Andrew.


----------



## steve2151

Quote: 





bishyb said:


> A question about this amp (sorry if this has been asked/answered already):
> 
> - Can you control the volume of the rca outputs using the internal volume controls?  Would like to output the rca to a set of studio monitors and control the volume via the headphone amp if possible.
> 
> Andrew.


 
   
  Yes, there is built in preamp function. You can also disable the volume control and use the amp in line out mode with a single jumper.


----------



## thegrobe

Could anybody share some impressions of this unit paired with a fairly clean, uncolored DAC driving LCD-2.2's?
Thanks!


----------



## thegrobe

Hi all,
  Although it seems this thread is drying up a bit....I have some late to the party stuff to add. 
   
  I have an update for my post above. I went ahead with the SA-31 and have had it here for a week. I posted a quick write-up on the "Amp recommendations for LCD-2" thread, but I'll share it here as well. Short version is this is a great amp. Get one if you can!
   
  Link:  
   
  http://www.head-fi.org/t/495631/amp-recommendations-for-audeze-lcd-2/6195#post_947172
   
  Aaaaand.. my copy and paste for your reading enjoyment:
   
 I have had the Audio-GD SA-31 here for a week, using the DACmini CX (1ohm) > SA-31 > LCD-2.2. I am pretty satisfied with this setup. The DACmini/LCD-2 combo is supposedly nearly a perfect match (from what I've read from several on here) so I was not really expecting to get any kind of improvement. My expectations were low. Before you read on, be aware that I have not used any other amps with the LCD so I don't have any comparisons with the names that always pop up on this thread. Just my portable amp, Leckerton UHA 6S-MKII, and the DACmini all-in-one. 
  
 With the DACmini feeding the LCD, the sound is really good. However I couldn't help but feel that I wanted to try an amp with some more wattage behind it to see if I could bring a bit more out of the LCD. Direct out of the DACmini, my issue is wishing for a bit more bass presence. And I also feel the sound of the combo is the best when the headphones are driven at a bit higher volume, and when you go just a bit past that I can feel the amp section is straining just a bit. Bass gets a bit looser, highs a little more harsh. (very very minor amounts) So my sweet spot with that setup is just near the cusp of pushing the amp sections ability. Probably a little room for improvement. 
  
 The Audio-GD SA-31 puts out 10 watts @ 40 ohm (so what is that at the LCD's 50 ohm?) I don't know. Maybe 9 watts? Plenty, anyway. Diamond differential design. There are 3 adjustable "warmth" settings that can be set with internal jumpers. "0", "Warm 1" and "Warm 2". This amp, while having the description of "musical flavor" and "warmth settings"...well, don't let that fool you into thinking it will be a muddy mess with the LCD. Quite the opposite.
  
 This amp pumps out gobs of clear goodness and the warmth seems to be affecting harmonics and space more so than primary notes. Compared to direct out of the DACmini, it is actually cleaner and more detailed. Adding the jumpers to the "warm 1" setting gives more depth to the space and a wonderful lifelike sensation while not affecting the clarity whatsoever. I hate to use this term, buuuuuttt..."3D" works here. That's the difference. "warm 2" is just on the cusp of affecting details a bit. Bass/ headspace gets bigger and deeper...still perfectly suitable for the LCD. I settled on "warm 1" for now. Best of both worlds. I have read on some posts describing the Audio-GD amps darkness or warmth as "Kingwa dark". Whatever that guy is doing, he is doing it right. My biggest fear was that this amp would be too dark or warm for the LCD. Not an issue. 
  
 Drawbacks? I wish it had a volume knob rather than buttons. But it was a design choice for sound quality reasons. Also, I need to now invest in some good RCA interconnects, since it's not one box anymore . (I'm using kind of cruddy ones now) Also the blue display lights are way too bright, but a touch of window tint fixed that. My wife says it's ugly. But she says that about everything audio related. 
  
 Anyway, just initial impressions. This amp gives you all juice you need for the LCD-2 without breaking a sweat. The real surprise here is the added warmth and soundstage without affecting clarity at all. This reminds me of some of my favorite gear, Heir Audio 8.A and the LCD-2. They can be warm, and fun, but serving up details as well. Speaking of which, the amp has no issue driving sensitive custom IEM's as well. Switch it to low gain and you're good. The DACmini is just too strong for my Heir 4.A's (the 8.A's are okay). I had to run the DACMini to my UHA amp to use it with the 4.A's. I can plug those right into the SA-31 and get good results. 
  
 Is it worth adding a $500 amp to the DACmini for the improvement? well that's up to you. Everybody has done stupider things! ha ha. I really would love to be able to try some other amps in this price range or some of the other gear discussed on this thread to see how the SA-31 compares.


----------



## JWahl

Quote: 





thegrobe said:


> Hi all,
> Although it seems this thread is drying up a bit....I have some late to the party stuff to add.
> 
> I have an update for my post above. I went ahead with the SA-31 and have had it here for a week. I posted a quick write-up on the "Amp recommendations for LCD-2" thread, but I'll share it here as well. Short version is this is a great amp. Get one if you can!
> ...


 
   
  That sounds like a pretty accurate description.  I think it's an optimal amp with the LCD series, though didn't hear the LCD-2 with it, just the LCD-3.  As an amp for the HD800 though, I ended up replacing it with a Burson Soloist as I feel it pairs better with the HD800.  Not that it was bad with the HD800 by any means, especially for the price, I just felt the Burson had better synergy.  Although I really liked it the the LCD-3, I also tried the HE-6 on it expecting good things but was honestly underwhelmed.  
   
  I think HE-6 owners looking at this as an amp would need to do the gain mod to better match with the HE-6.  Even with high gain and a higher than average source, I was still almost maxing it out.  I still contend that speaker amps bring out the best in the HE-6.
   
  And also, the Audio-GD gear doesn't have knobs, not because of sound quality.  He previously integrated that type of volume control with knobs.  The knobs were removed because his customers were complaining about the knobs breaking during shipment, so he stopped putting knobs on them.


----------



## thegrobe

Quote: 





jwahl said:


> That sounds like a pretty accurate description.  I think it's an optimal amp with the LCD series, though didn't hear the LCD-2 with it, just the LCD-3.  As an amp for the HD800 though, I ended up replacing it with a Burson Soloist as I feel it pairs better with the HD800.  Not that it was bad with the HD800 by any means, especially for the price, I just felt the Burson had better synergy.  Although I really liked it the the LCD-3, I also tried the HE-6 on it expecting good things but was honestly underwhelmed.
> 
> I think HE-6 owners looking at this as an amp would need to do the gain mod to better match with the HE-6.  Even with high gain and a higher than average source, I was still almost maxing it out.  I still contend that speaker amps bring out the best in the HE-6.
> 
> And also, the Audio-GD gear doesn't have knobs, not because of sound quality.  He previously integrated that type of volume control with knobs.  The knobs were removed because his customers were complaining about the knobs breaking during shipment, so he stopped putting knobs on them.


 
   
  I'll keep in mind not to set my sights on the HE-6 with this then. But yeah, I can certainly give the LCD a thumbs up with it.
   
  That's interesting about the volume knobs! I read something about the volume control being "relay based to prevent channel imbalance and improve sound quality". I was assuming that was explaining the buttons but I guess the knobs use the same circuit. I any case, sounds good! I pretty much use replay gain and set it, so it's not like I'm fiddling with it much. 
   
  I see you sold yours, congrats. I'm glad you found a buyer quickly!


----------



## JWahl

Yes, I wish they still did use the old volume knobs with the Relay-Resistor volume Control.  Here is a picture I found of an old Audio-GD Phoenix showing the same volume control type but with a knob.  The buttons are kind of a pain if you want to make a quick volume adjustment.


----------



## Utopia

Great to see some activity in this thread again - the SA-31 deserves more attention than it's been getting IMHO. I've had mine for three months now and couldn't be happier. I first bought it without the remote, and thought the volume control felt awkward, but once I got the remote I was very happy even with that aspect of the amp. It's great to have the volume control right next to my keyboard - and if I ever upgrade to something that lacks a remote I'm sure I'll miss it. I'm running the SA-31 with Beyerdynamic T1, a combination that gives a very clear and very spacious sound - actually probably a little on the bright side even on the Warm 2 setting, but it could also just be that it's very revealing of poor source material.


----------



## i019791

Quote: 





jwahl said:


> And also, the Audio-GD gear doesn't have knobs, not because of sound quality.  He previously integrated that type of volume control with knobs.  The knobs were removed because his customers were complaining about the knobs breaking during shipment, so he stopped putting knobs on them.


 
  They still use knobs at their cost sensitive gear (up to Compass 2, which is same size as SA-31). It could be that they improved their packaging / design at some point and knob breaking during shipment has become scarse - if so a sound quality reason might justify the volume buttons.


----------



## AManAnd88Keys

Just read the descriptions on Audio-GD, there are your answers.... :
   
Volume control:
        [size=x-small]SA-31 with remote control, the volume control applied resistors components, can avoid channel imbalance and improve on sound quality than normal potentiometer.[/size]
 [size=10pt]        The volume control is also different from conventional technology. Conventional volume control technology is  [/size] [size=x-small]the volume control implement in the analog amp input stage through a volume pot to reduce the signal  . The volume pots quality effect the sound quality direct , the low quality volume pot cause lost the detail and channels imbalance cause the soundstage distortion  . Even the high performance volume pot still cause the detail lose. Whatever quality volume pots, must cause the S/N worst .[/size]
[size=10pt]    [/size][size=x-small]    In SA-31, the volume applied parallel connection control technology, the audio signal had not through the volume pot feed to the amp . So its quality have not effect by the volume pot quality .
          SA-31 applied two channels digital control relays based volume control. The volume board  through changing the DALE resistors to control the volume for avoid channels imbalanced ,achieve the best performance and sound quality of the gear.
         SA-31 have 80 steps volume level control in both high gain  and low gain mode. The total 160-step volume control ensures smooth control of the volume level.[/size]


----------



## Clemmaster

Quote: 





amanand88keys said:


> Just read the descriptions on Audio-GD, there are your answers.... :
> 
> Volume control:
> [size=x-small]SA-31 with remote control, the volume control applied resistors components, can avoid channel imbalance and improve on sound quality than normal potentiometer.[/size]
> ...


 
   
  You can still use volume knob to achieve this (rotary coder or the likes) 
  The feel might be different than a regular pot, though. I really like the feeling of the pot on the cheap  NFB-15.32.


----------



## oldson

its a shame (for me) that their is not more he-6 owners out there that have tried this amp.
  for this money would a used speaker amp and he-adapter not perform better?


----------



## steve2151

Quote: 





oldson said:


> its a shame (for me) that their is not more he-6 owners out there that have tried this amp.
> for this money would a used speaker amp and he-adapter not perform better?


 
   
  I used to own the SA-1/SA-31 stack and was able to get good listening volume on the HE-6 between 20-35 on high gain depending on the loudness level of the track. However, I also had the SA-1 set to high gain as well (2.5 V).


----------



## Mad Lust Envy

i019791 said:


> They still use knobs at their cost sensitive gear (up to Compass 2, which is same size as SA-31). It could be that they improved their packaging / design at some point and knob breaking during shipment has become scarse - if so a sound quality reason might justify the volume buttons.




Actually, the Compass 2 is about 2/3 of the depth, but same width and height. The SA-31 is looong.


----------



## Ishcabible

I got mine today and I have to say, it pairs quite well with the K702. The warmth of the amp compliments the K702 (non Annie) beautifully.
   
  EDIT: JWahl's suggestion to me was correct; definitely use a DAC with an output impedance of over 2V with this amp. My Gamma2's output voltage is 1.4V while the iDAC I have beside me has an output voltage of 3.3V. While the iDAC is inferior to the Gamma2 with my other amplifiers, the iDAC almost removes a veil from the midrange when compared to the Gamma2.


----------



## JWahl

Quote: 





ishcabible said:


> I got mine today and I have to say, it pairs quite well with the K702. The warmth of the amp compliments the K702 (non Annie) beautifully.
> 
> EDIT: JWahl's suggestion to me was correct; definitely use a DAC with an output impedance of over 2V with this amp. My Gamma2's output voltage is 1.4V while the iDAC I have beside me has an output voltage of 3.3V. While the iDAC is inferior to the Gamma2 with my other amplifiers, the iDAC almost removes a veil from the midrange when compared to the Gamma2.


 
  Glad to hear your enjoying it 
	

	
	
		
		

		
			





  And also confirming my suspicion about the input voltage.  The amp must have a lower input sensitivity than other similar amps.  probably to match most Audio-GD DAC's output voltage of 2.5v.


----------



## Ishcabible

With my Gamma2, I have to turn up my Yamaha HP3 to 79 on high gain, which is incredibly disconcerting...It's a pretty significant upgrade to the amps I have now though.


----------



## thegrobe

Well, I've got the SA-1.32 DAC here now to pair with the SA-31. 
   
  While I've only had it a few days, the initial reaction is pretty good! After I get some more listening time in I'll post more including comparisons to the DACmini's DAC section. My main worry was that the SA-1/SA-31 combo may be too dark for the LCD-2... pairing the "musical" DAC and 'musical" amp may be too much for the LCD-2.2. Well, I can say that is not a worry at all. At least for my tastes. The combo sounds great. Not too dark or too muddy at all. Very natural. Currently I have the SA-31 on "warm 1".
   
  I had some email exchanges with Kingwa to decide on which DAC would be best for my setup and actually decided on the SA-2. Kingwa says that it is actually a bit more neutral than the SA-1 and that would be a better overall setup to have a more neutral DAC and let the amp add any color. So I still am set on getting the SA-2 as soon as possible but picked up a used SA-1 to use in the meantime. 
   
  So the SA-1.32 appears to be pretty promising! It will keep me busy until I can get the SA-2...More impressions to follow.


----------



## steve2151

I sold thegrobe my SA-1 after realizing that I prefer a colder sound. Since I use no warmth jumpers with the HE-6 and prefer the thinner and faster sounding Arete with the HD 800, I replaced my SA-1/SA-31 with a Reference 8/Master 8 from the sale forums. The new stack is balanced and does the little things better (quicker transient speed and more detailed instrument separation with slightly more bass impact) but diminishing returns is very noticeable at this price point.
   
  Good to see that you're enjoying the dac and have managed to get the USB32 installed. Let us know how the SA-1 stacks up against the DACmini and if you end up buying it, the SA-2.


----------



## oldson

[size=small]10000 MW /  40 ohm [/size][size=small][/size]
 [size=small][/size]
 [size=small]8000 MW /  50 ohm [/size][size=small][/size]
 [size=small][/size]
 [size=small] 4000 MW  /  100 ohm[/size][size=small][/size]
 [size=small][/size]
 [size=small]1400 MW / 300 ohm[/size][size=small][/size]
 [size=small][/size]
 [size=small]700 MW / 600 ohm[/size]
   
  [size=small]these output figures, taken from the website, do they refer to the balanced or single ended outputs?[/size]


----------



## Mad Lust Envy

The SA-31 is single ended ONLY, despite it having the output jack typically associated with balanced output.


----------



## oldson

Quote: 





mad lust envy said:


> The SA-31 is single ended ONLY, despite it having the output jack typically associated with balanced output.


 
  yeah sorry i just read that further back in the thread , thanks


----------



## thegrobe

Quote: 





steve2151 said:


> I sold thegrobe my SA-1 after realizing that I prefer a colder sound. Since I use no warmth jumpers with the HE-6 and prefer the thinner and faster sounding Arete with the HD 800, I replaced my SA-1/SA-31 with a Reference 8/Master 8 from the sale forums. The new stack is balanced and does the little things better (quicker transient speed and more detailed instrument separation with slightly more bass impact) but diminishing returns is very noticeable at this price point.
> 
> Good to see that you're enjoying the dac and have managed to get the USB32 installed. Let us know how the SA-1 stacks up against the DACmini and if you end up buying it, the SA-2.


 
  Wow the Ref 8/Master 8 must be quite a combo! I wonder if the improvements you describe lie more in the 8 DAC chips vs. 4 chips ...or better power conditioning..or balanced output? Hmm the mystery! I think for a single ended setup, what I have is here now is pretty good. The USB-32 is a dream compared to the 8802 interface. However, I see that AGD just released a v1.2 driver for the 8802 the other day so maybe that will narrow the gap between the two. (Of course, right after I upgrade, LOL)
   
  That stack is also diamond differential, right? but not "musical" series?


----------



## steve2151

Kingwa includes the Reference 8 in his list of diamond differential products in the history section of the SA-31 page, so I figure it counts. Although the SA-1 is the first dac to carry the SA name, it looks like all diamond differential dacs fall under the musical series.
   
  It's probably the balanced operation that's making most of the difference here. The Reference 8 is not much better than the SA-1 with my SRM1/MK2 and Arete, but you do get a more spacious presentation on the Master 8 vs the SA-31. 
   
  On the Reference 8 product page, Kingwa mentions exactly that: "If the balance output is not needed and you have not plan going to balance system in near future, the Reference 9 is OK and costs $480 less".


----------



## CJG888

Has anyone here tried the SA-31 with the HD600s?


----------



## steve2151

Quote: 





cjg888 said:


> Has anyone here tried the SA-31 with the HD600s?


 
   
  It worked well enough for me with my HD 580. Results in a smooth and laid back sound with decent bass weight. Recommended if you have a preference for a warmish frequency response..


----------



## CJG888

Have just placed my order.

Will be using it with HE-500, HD600 and ATH-A900X


----------



## Utopia

Quote: 





cjg888 said:


> Have just placed my order.
> 
> Will be using it with HE-500, HD600 and ATH-A900X


 
   
  SA-31 + HE500 is a stunning combo! I traded my HE500 for T1 but will get the Hifimans again as soon as I can.


----------



## Mad Lust Envy

Used the SA-31 with:

LCD2, HE400, HE-4 (incredibly hard to drive), HD650, K702 65th Anniversary as some notables.


All of them sounded magnificent with it.


----------



## Clemmaster

HE-4, HE-500 and HE-5LEs for me, all with great success!
   
  I can't say the HE-400 sounded good on it, because they don't sound good in general


----------



## CJG888

Is the front panel XLR socket intended for the AKG K1000? Does this combination work?


----------



## conquerator2

Quote: 





cjg888 said:


> Is the front panel XLR socket intended for the AKG K1000? Does this combination work?


 
   
  I would hope so.
  Probably not intended, but it should work fine.
  Once again dependent on the source as well (definitely not with portable devices, most likely with PCs, laptops, etc)
   
  I am just guessing here, perhaps someone can chime in


----------



## HPiper

I am considering ordering some equipment from Audio-gd. It kind of appears to be a bit complicated, ordering and paying for the equipment. Can someone who has actually done this kind of give me a 'heads-up' on the procedure.


----------



## HaVoC-28

Quote: 





hpiper said:


> I am considering ordering some equipment from Audio-gd. It kind of appears to be a bit complicated, ordering and paying for the equipment. Can someone who has actually done this kind of give me a 'heads-up' on the procedure.


 

 Send their a mail (see "contacts us") with equipement you want specify voltage region , custom options if needed, they will get you back with some kind of bill (check that everying is correct) , and their paypal account or bank transfer , when payement is done sent reply , and they will say that they receiv your payment and will contact you when goods shiped  .
   
  well at least it's what happened last time i ordered some goods from A-GD .


----------



## CJG888

It's arrived and is warming up. Impressions to follow...


----------



## CJG888

I've now had a chance to listen to the SA-31, albeit briefly.

First impressions were not great. The amp arrived on time and in good condition, but some of the fit and finish reminded me of British "cottage industry" hi-fi of the 80s (think Myst, early Exposure etc.). The enclosure Itself is solid and undamaged, and is clearly made from high-grade aluminum. Many of the screws, however, are not countersunk. The remote appears to be milled from a solid aluminum billet (good ), but the battery compartment cover is a thin sliver of aluminum which bows out in the middle, and the screws attaching it stand proud, to scratch whatever surface it is resting on (bad :mad. Also, the backplane has clearly been lifted from an NFB-6 (some of the RCA sockets are labelled "XLR" and "ACSS"). Model name and serial number are handwritten on sticky labels.

I don't want to belittle Kingwa's achievement - this is a low-volume, specialist product built by a small company, and the bulk of the money has been spent where it matters: on the inside! It's just that we have been spoilt by the quality of companies such as Opera Consonance or Matrix' casework. 

Now to the important bit: the sound. I tried it with the HE-500 and HD600. Interestingly, the 300 Ohm Sennheisers need about as much power to drive them as the HE-500s (unlike the transformer-coupled tube amp I am used to). All listening was carried out on the low gain setting, and never above a volume setting of 30. The source was the Opera Consonance CD2.3, an upsampling CD player with a tube output stage producing about 2.3V.

Initial impressions were of a warm, lazy sound with little midrange detail or transparency. The HD600s were soporific, the planars just so-so. I couldn't believe that this was all the amp was capable of, so I left it running for about 3 hours on the HE-500s, and came back later. I presume this must have something to do with the capacitors needing to form, as the sound was transformed. Still not perfect, but much clearer and more transparent. Where it improves on the Cyber 20 is in the area of soundstage width (enormous) and bass extension (seemingly bottomless). Dynamics are also a major improvement over the tube amp! Where it still loses out to the Cyber 20 is in absolute midrange transparency and image depth. The SA-31 is "CinemaScope" rather than holographic. 

I tried the HD600s again early this morning, before leaving for the office - still very veiled, but an absolutely black background. I have yet to try the Audio Technicas.

On balance, then, an interesting niche product with considerable potential. I do feel that it is perhaps better suited to low impedance cans (especially orthos), and that it will need MUCH more burning-in.

Am I correct in assuming that it is factory set to the least warm setting? I haven't opened it up....

When it has perhaps 100 or so hours on the clock, I will publish a full review. This amp promises to be something of a big block V8 for your ears...


----------



## Utopia

I've had some of the same experiences. I came from an M-Stage to the SA-31, and was a little bit worried at first. The M-Stage is an absolute bargain, sounds great right away, and the build quality is flawless. The SA-31 looked a bit rough, and sounded odd in the beginning. My impression is that it takes quite a bit of time, definitely more than 50 hours, to get it to sound the way it's supposed to. It may have taken several hundred hours, but now I'm totally happy with it. It's fast and powerful, has the black background people often talk about with Audio GD gear, and a great sense of spaciousness. Also, the three warmth settings are very useful (even if it seems like intentional coloration of the sound, which I guess is "bad"). On the HE500 I used the default setting (no added warmth), but on the T1 I've been experimenting with the other two. I got pretty much the same output level with both phones, despite very different impedance and sensitivity (the T1 is 600 ohm).


----------



## Utopia

One more thing, I ordered an optional -10 dB/0 dB volume board from Kingwa, which I think gave me a better range of usable volume settings than the 0 dB/+ 10 dB default volume board.


----------



## CJG888

Did you change the gain board yourself later, or did you order a custom version with it installed?

Just out of interest, does yours also have an NFB-6 back panel?


----------



## Utopia

I ordered the volume board later, for $15, with the remote for another $50, which I hadn't ordered at first. It was very easy to change the board myself by just unplugging two cables (no soldering, proper connectors). 
   
  And, yes, it looks like I also have the NFB-6 back panel, with markings for XLR out instead of just Out.


----------



## CJG888

Are there any other tweaks you would recommend?


----------



## CJG888

The ATH-A900X is a good match. It really benefits from the black background, and the soundstage is W I D E.


----------



## Utopia

Quote: 





cjg888 said:


> Are there any other tweaks you would recommend?


 
   
  The only thing is that the remote is very useful to have, but I remember you already have that. I always listen to music in front of the computer, but the remote and the long cable on the T1s makes it easier to move away from the screen for a while and just listen to music.


----------



## CJG888

Does yours also take a long time to warm up (between switching on and the controls being released)?


----------



## thegrobe

Quote: 





cjg888 said:


> Does yours also take a long time to warm up (between switching on and the controls being released)?


 
   
  What do you mean exactly?
   
  When you first turn the unit on, the display blinks a few times. When it stops, you need to push and hold either the volume "up" or "down" button for a couple seconds. Then the amp is ready. If you hold the volume "up" it remembers the last set volume. If you hold volume "down" it sets the volume to zero. .
   
  ...I'm not really sure what would happen if you didn't push one of those buttons, maybe that is what you are experiencing? 
   
  Also, I notice a good half hour or so warmup is good to get the best sound out of this baby.


----------



## JWahl

Quote: 





cjg888 said:


> I've now had a chance to listen to the SA-31, albeit briefly.
> 
> First impressions were not great. The amp arrived on time and in good condition, but some of the fit and finish reminded me of British "cottage industry" hi-fi of the 80s (think Myst, early Exposure etc.). The enclosure Itself is solid and undamaged, and is clearly made from high-grade aluminum. Many of the screws, however, are not countersunk. The remote appears to be milled from a solid aluminum billet (good
> 
> ...


 
   
  Yes, it sounds like garbage when you first turn it on (exaggerated).  Needs a slight warm up period.  My Soloist is the same way as well.  I believe the stock configuration is no jumpers, but you could always open it up to see.


----------



## tim3320070

Add the jumpers, not a huge change though.

Every agd piece I have purchased needed a few days of use and a bit of warm up to sound optimal.


----------



## thegrobe

I find the "warm 1" setting (one pair of jumpers) to be my favorite. Adds a touch of the "musical" voodoo that Kingwa put in there but not too much. That's with my setup however.


----------



## CJG888

I have found that this amp sounds best driving the HE-500s on the high gain setting, with the volume set to 20 or below. My source is an Opera Consonance CD2.3 Mk III with an output of 2.3V. On the low setting, the sound lacks dynamics and sounds too "soft" and "rounded". Is "high" the recommended gain setting for orthos?


----------



## Clemmaster

Quote: 





cjg888 said:


> I have found that this amp sounds best driving the HE-500s on the high gain setting, with the volume set to 20 or below. My source is an Opera Consonance CD2.3 Mk III with an output of 2.3V. On the low setting, the sound lacks dynamics and sounds too "soft" and "rounded". Is "high" the recommended gain setting for orthos?


 
   
  Sound great of low gain for me.
   
  There's a boost at 48 on the volume. Don't know if its a resistor miss-match that gives a bigger volume boost than the other steps or anything but the sound "awakens" past this point


----------



## Mad Lust Envy

That might be where the the amp works at it's optimal point. Like the Fiio E9 working at it's best between 10-12 o clock on the volume knob. Confirmed by Fiio themselves.


----------



## CJG888

So I should get the lower gain volume board, then?

I tend to listen fairly quietly. The A900X become too loud to listen to above ca. 18 on low gain!!!


----------



## Clemmaster

Quote: 





cjg888 said:


> So I should get the lower gain volume board, then?
> 
> I tend to listen fairly quietly. The A900X become too loud to listen to above ca. 18 on low gain!!!


 
   
  Does it provide a smooth enough volume control on the first 18 steps? If yes, you don't need the board.


----------



## CJG888

Yes, it does. I was just wondering whether it performed better with less attenuation at the volume control stage, and lower gain (assuming that the gain control is not just a "rough" volume control).

I guess it all depends what the gain selector actually does.


----------



## Clemmaster

Quote: 





cjg888 said:


> Yes, it does. I was just wondering whether it performed better with less attenuation at the volume control stage, and lower gain (assuming that the gain control is not just a "rough" volume control).
> 
> I guess it all depends what the gain selector actually does.


 
   
  Yeah, that make sense if the amp has the ordinary attenuator + gain.


----------



## thegrobe

Quote: 





cjg888 said:


> I have found that this amp sounds best driving the HE-500s on the high gain setting, with the volume set to 20 or below. My source is an Opera Consonance CD2.3 Mk III with an output of 2.3V. On the low setting, the sound lacks dynamics and sounds too "soft" and "rounded". Is "high" the recommended gain setting for orthos?


 
   
  Quote: 





clemmaster said:


> Sound great of low gain for me.
> 
> There's a boost at 48 on the volume. Don't know if its a resistor miss-match that gives a bigger volume boost than the other steps or anything but the sound "awakens" past this point


 
   
  I use the SA-31 on low gain. This is perfect with LCD-2/LCD-3. With the SA-1.32 DAC on high gain, outputting 2.5v. Volume range lies anywhere between 20-50. This puts the amp a good way towards the middle of the range. I can go much quieter or louder if need be and sounds full and dynamic throughout. I always understood that you should use as little gain as you need. Higher gain will raise the noise floor and also further amplify any misc. noise. No need to use high gain if low gets the job done. 
   
  I also find that high gain may sound a bit punchier ..."maybe" ...but this may be a mind trick because the amp is so powerful at low numbers on the dial. But it also gives very little useable volume, somewhere between 5-15. A little more raggedness to the sound too probably due to too much gain being applied. Really spend some time with low gain, you may find the sound is full, dynamic, and balanced. Just my opinion and preferences. 
   
  I also notice that little "jump" at 48, low gain. Wonder what that is,..sometimes I get the amp that high, sometimes not. Sounds good on either side of 48 though. I don't know if it does that at 48 on high gain....and I'm not going to find out, it would shred your eardrums!


----------



## Mad Lust Envy

The HE-4 will definitely pass 48 on high gain.


----------



## CJG888

Yesterday, I tried the HE-500s at 48 on low gain. A little on the loud side for me, but definitely better.

Maybe the amp just needs some more burn-in. We're at about 15 hours now - because of the heavy electrical storms in Shanghai at this time of year, I can't leave it running overnight...

The HD600s are also sounding better and better.

The A900X can only be listened to at 15 or lower on low gain... Any more is dangerous to hearing! The bass seems a little overblown - maybe I will try the A1000 pad mod. This is said to increase comfort and reduce bass bloat. I do sometimes need a closed can for practical reasons (e.g. the air conditioning running at full blast when it's 45 degrees outside).


----------



## Mad Lust Envy

The HE4 needs near HE6 levels of power. He500 is a pushover in comparison (the HEx00 line is designed to be driven by most amps, while the single digit line needs specialized amps, or really high powered ones).


----------



## thegrobe

Quote: 





mad lust envy said:


> The HE-4 will definitely pass 48 on high gain.


 
   
  I'm sure those "single digit" HiFimans would! I was just referring to LCD's (pushovers, like HE-500, right? LOL) with a 2.5v signal coming into the amp...Waaaaaaayyyy too high a volume!
   
  Quote: 





cjg888 said:


> Yesterday, I tried the HE-500s at 48 on low gain. A little on the loud side for me, but definitely better.
> 
> Maybe the amp just needs some more burn-in. We're at about 15 hours now - because of the heavy electrical storms in Shanghai at this time of year, I can't leave it running overnight...


 
   
  I am guessing you need many more hours of burn in for things to fully settle. I say "guessing" because I bought mine used and had about 50-100 hours on it now. It seems to be settled for the most part. Everything I've read about the Audio-gd gear mentions at least 100 hours of use or more for burn in.
   
  How do you find the sound quality when the volume is less than 48? That little jump from 47-48 sounds to me like one or two of the volume steps are "missing" or just a small jump in volume if that makes sense. I'm not sure if there's any change in quality, really. It just tricks you into thinking it's more "alive" because it's suddenly louder.


----------



## ManAtWork

I am interested to this product due to the diamond difference circuit design. However, I would like to have any feedback from existing users how it sounds after fully burn-in. Tonal Balancing is the area which I concern. TIA


----------



## tim3320070

It has essentially no coloration, very detailed but without harshness and nice 3D sound (wide soundstage).


----------



## ManAtWork

Quote: 





tim3320070 said:


> It has essentially no coloration, very detailed but without harshness and nice 3D sound (wide soundstage).


 
   
  Thanks, sounds great.
  How about the bass?


----------



## Clemmaster

Quote: 





manatwork said:


> Thanks, sounds great.
> How about the bass?


 
   
  The bass is well controlled from what I can tell.
  I has a very nice slam with the HE-500 & HE-5LE.
   
  It compares very well with the built-in amp in my NFB-27 (which is supposed to be based on the Master-8. To what extent, I don't know) and adds the musical flavor without trading for details or resolution.
  I actually prefer it overall because the musical flavor is a *very* nice addition to the sound. Also, it does all this single-ended when the NFB-27 amp is balanced. The sound-stage is roughly the same size (bigger, perhaps), which is a feat considering this is usually an advantage for balanced amps


----------



## ManAtWork

Quote: 





clemmaster said:


> The bass is well controlled from what I can tell.
> I has a very nice slam with the HE-500 & HE-5LE.
> 
> It compares very well with the built-in amp in my NFB-27 (which is supposed to be based on the Master-8. To what extent, I don't know) and adds the musical flavor without trading for details or resolution.
> I actually prefer it overall because the musical flavor is a *very* nice addition to the sound. Also, it does all this single-ended when the NFB-27 amp is balanced. The sound-stage is roughly the same size (bigger, perhaps), which is a feat considering this is usually an advantage for balanced amps


 
   
  I like what you said, "add the musical flavor without trading for details or resolution", this is what I am seeking for. You know, I worried if there was trade off on resolution when companies claimed their products are musical. 
	

	
	
		
		

		
		
	


	




 If so, with considering the price tag of SA-31, it worth to have a try for any new comer of Audio_GD like me. I am attracted with the diamond difference design while I am a big fan of Accuphase.


----------



## thegrobe

manatwork said:


> I like what you said, "add the musical flavor without trading for details or resolution", this is what I am seeking for. You know, I worried if there was trade off on resolution when companies claimed their products are musical.
> 
> 
> 
> ...




Manatwork, the comments posted above are pretty much the same as my experience with the SA-31. I think I've posted on this thread that the "musical" flavor to me, seems to bring out the details of harmonics and reverberations, etc., if that makes any sense. The best way I can describe it. But it's not artificial sounding or anything, very natural and lifelike. Very subtle. 

The other thing is the warmth jumpers add some “fullness" to the bass as well.Probably too much for my tastes with the "warm 2" setting but "1" is very nice.

I really am liking this amp with the LCD-3/LCD-2.....


----------



## ManAtWork

Thanks your guys for your user comments. I am now pretty sure this is what I want.


----------



## CJG888

I'm finding myself (unexpectedly) enjoying the combination of SA-31 and HD600 more and more. Have just got back from a weekend business trip to Hainan and am listening to Jean-Guihen Queyras play Haydn's second Cello Concerto (with the Freiburger Barockorchester under Petra Muellejans). An excellent recording, by the way (Harmonia Mundi HMX 2961816).
   
  Gain is set to low, volume to 40.


----------



## ManAtWork

CJG888, I assume SA-31 has the characteristics similar with my Graham Slee Solo UL but might be better in SQ. This kind of sound is particular suitable to pair with most of Sennheiser cans.


----------



## CJG888

It keeps getting better.

Bill Evans Trio: Sunday at the Village Vanguard via the HE-500s tonight


----------



## Uchiya

Is the listed power rating for SE or Balanced output?


----------



## thegrobe

Quote: 





uchiya said:


> Is the listed power rating for SE or Balanced output?


 
   
  The SA-31 is single ended only. The 4 pin XLR is just for connection flexibility with balanced headphones but is still a SE output.


----------



## Dafo

Hi there
  I have a few questions regarding the sa31:
   
  Does it have above average bass-slam or is it neutral in the bass region?
   
  I consider the Just Audio uha-120 to have above average in bass for reference. Has anyone heard both and would be so kind to do a quick comparison?


----------



## Utopia

I can only tell you about the SA-31, and of course only my opinion, and with my phones. So far I've tried it mostly with the Beyerdynamic T1, Hifiman HE-500 and Denon AH-D5000. With the T1 I feel that the bass is very neutral. With the HE-500 the bass was punchy and fun, and with the Denons, which are known to be punchy and fun, the bass was surprisingly controlled (a great combination, except for the high sensitivity of the headphones, which made for a very limited volume range with this amp).
   
  I'm not sure what the right conclusion should be, but I believe the amp is very neutral in the bass region, but with plenty of power and control. It's not a neutral that is limited in any way.


----------



## Dafo

Ok, thank you very much for your precise answer, I appreciate it.


----------



## Clemmaster

The SA-31 is neutral with an ever so slightly rolled-off treble.
  It gets its warmth from harmonic distortion rather than rolled-off bass & treble like some tube gear tend to have ('n'-shaped?).


----------



## Dafo

Brilliant, I know exactly what you mean. Thank you.


----------



## sayh

Out now! A refined control, higher gain and power SA-31se promo in for ordering.
  Great or not for HE-6, we shall see..
   
http://www.audio-gd.com/Pro/SA/SA31/SA31EN.htm
   
   
*What's new on the SA-31SE:*
*1, Boost the gain from 10DB (SA-31)  to 20DB (High gain model on SA-31SE), even with low output level sources ( like 1.5VRMS), still have enough gain and power for drive the HE6 and low sensitivity headphones.*

*2, For the high sensitivity headphone and preamp output model , we have redesign the new exponential volume control board built in 14 pcs relays (SA-31 only had 8 pcs), it have 100 steps and 100DB level control range, allow users  very fine to adjust the volume.*

*The below picture show the volume characteristic , green is with the SA-31, red is with the SA-31SE .*
*

*
*3, Redesign the control software, users can quite quickly continuous adjust the volume on front panel, from volume 0 to volume 50, only need around 5 seconds.*

*4, Built in OCC wires .*


----------



## CJG888

Brilliant! You buy something, and a month later it is obsolete...

At least in the automotive industry, we manage our run-outs properly.

:mad:



Anyone know if the new volume control board can be retro-fitted?

I may just get tempted to take it all apart and get tweaking....


Does anyone know of a source of Black Gate capacitors?


----------



## Utopia

Quote: 





> Anyone know if the new volume control board can be retro-fitted?


 
   
  I have no idea, but I know it was very easy to swap the old volume board for one with different gain settings, so it could - maybe - be possible.
   
  I know some people thought the gain was low on the SA-31. For me it seemed a little high, or at least a little bit difficult to set to the desired volume at lower volume levels, so I bought a volume card with lower gain. Perhaps Kingwa has found a good balance now, with volume steps that are exponential instead of linear.


----------



## CJG888

I find the volume control OK with the HE-500 and HD600, but with the ATH-A900X, I can only safely go up to about 15 on low gain!

Also, I wonder if the revised choice of internal wiring may brighten the sound up a bit. At some point in the future (when I have more time), I might consider trying silver hook-up wire.


----------



## Clemmaster

Still no button for the warmth setting, argh!
The faster volume control is much welcomed, though.


----------



## Kingwa

The SA-31 easy modify to SA-31SE, the mother board even don't want take off. All operates are on the top side.
  If anyone have some DIY experiences , waiting some users reviews , if improved on the SA-31SE, can contact us for discuss the modify.


----------



## thegrobe

Kingwa, I'm a bit confused. is the low gain level not affected in the SA-31 SE? Is the "dB" boost only in high gain, correct? 

I would be interested in the DIY upgrade, and can post photos/tutorial here. Maybe I can buy the parts with my next order.


----------



## ManAtWork

After consulted some folks regarding this amp, I placed order just when the newer SA-31SE announced. Obviously I am in the first batch of SE version, and it finally arrived yesterday. It is still in burn-in period, and I have already found that my HD650 and HD800 sound very great with the "warm 1" setting.


----------



## thegrobe

manatwork said:


> After consulted some folks regarding this amp, I placed order just when the newer SA-31SE announced. Obviously I am in the first batch of SE version, and it finally arrived yesterday. It is still in burn-in period, and I have already found that my HD650 and HD800 sound very great with the "warm 1" setting.




Congratulations! It's a great amp. I look forward to hearing more about it, especially the new volume control. Gotta decide if I should update mine. 

Maybe unnecessary because I only use low gain?


----------



## ManAtWork

Quote: 





thegrobe said:


> Congratulations! It's a great amp. I look forward to hearing more about it, especially the new volume control. Gotta decide if I should update mine.
> 
> Maybe unnecessary because I only use low gain?


 
   
  Since I haven't the original version so I couldn't give out any regarding the changes, however, I noticed some users required higher gain then this SE version will be able to satisfy. It drives my 600ohm T1 very well, even without switch to high gain.


----------



## runswithaliens

Quote: 





thegrobe said:


> Congratulations! It's a great amp. I look forward to hearing more about it, especially the new volume control. Gotta decide if I should update mine.
> 
> Maybe unnecessary because I only use low gain?


 
   
  +1 on hearing more about the new volume control.  Since I don't listen at loud volumes and also want to use it for a variety of cans it would be pretty important that it doesn't get too loud too fast on low gain.


----------



## Uri Cohen

Did anyone purchase this amp for their Grados?
   
  I'm thinking about getting the SA-31 and using it as an amp for my RS2-i and my Cyrus CD player.  From the specs there's TONS of power for 32 ohm cans but I want to hear if this amp cause any musicial improvements on their Grados.


----------



## 148124

any more impressions about pairing sa-31 with he-4 ? I am gonna pick this one or new precision 1 ...


----------



## thegrobe

If anyone is interested, I have my SA-31 up for sale in the classifieds:

http://www.head-fi.org/t/675919/audio-gd-sa-31-diamond-differential-amplifier-pre-amp-wow-this-thing-is-awesome


----------



## Clemmaster

Quote: 





magicman said:


> any more impressions about pairing sa-31 with he-4 ? I am gonna pick this one or new precision 1 ...


 
   
  Excellent pairing with the SA-31 on "warm 2" setting.
   
  Very fast and detailed sound which suits fast paced genre the best, but also works very nice on most genre due to the added warmth in the mids (SA-31).


----------



## 148124

Quote: 





clemmaster said:


> Excellent pairing with the SA-31 on "warm 2" setting.
> 
> Very fast and detailed sound which suits fast paced genre the best, but also works very nice on most genre due to the added warmth in the mids (SA-31).


 
   
  thanks for an info !
   
  Have you tried any other amps from audio-gd with he-4 ? I am looking for something with mids from EF-5 but with power, bass and highs from Lyr for my HE-4 ...


----------



## BournePerfect

Ordered the SA-31SE today-looking forward to hearing it with my HD800s. I still have fond memories of my old C2-SA from years ago-which is still the best amp I ever heard with my T1s and AD2000s. Will be pairing with the DP-1 for the time being.
  
 -Daniel


----------



## Fearless1

bourneperfect said:


> Ordered the SA-31SE today-looking forward to hearing it with my HD800s. I still have fond memories of my old C2-SA from years ago-which is still the best amp I ever heard with my T1s and AD2000s. Will be pairing with the DP-1 for the time being.
> 
> -Daniel


 
 In theory that combo should have good synergy, the SA-31 is fairly warm and powerful. I look forward to your impressions.


----------



## Clemmaster

fearless1 said:


> In theory that combo should have good synergy, the SA-31 is fairly warm and powerful. I look forward to your impressions.


 
  
 The SA-31 is not THAT warm, even on the warmest setting. The M-Stage is much warmer, especially with the OPA627.
 Powerfull it surely is, though


----------



## Fearless1

clemmaster said:


> The SA-31 is not THAT warm, even on the warmest setting. The M-Stage is much warmer, especially with the OPA627.
> Powerfull it surely is, though


 
  
 I said it was fairly warm. The M-stage is tube-like warm, but the SA-31 is on the warmer side of neutral to my ears.


----------



## BournePerfect

Anyone here hear the C-2 SA? I'm hoping for that sound signature, as I always thought it would suit the Senns nicely. Great soundstage for ss, very musical, engaging, and perhaps a bit 'dark', but not warm. It was an incredible pairing with the T1s-got rid of their annoying treble for the most part, and brought out their somewhat lush mids. The AD2000 was also phenomenal on that amp-gave them a very smooth character I hadn't heard from them on other ss amps, extremely nice bass impact and tightness, and an incredibly black background. It's been a few years since I owned that amp, and it's one of only a couple that I really miss. And to think it never really sold at all before Kingwa pulled it-and it was only like $365 shipped iirc. One of the very first hp amps that could provide enough power for planars back then too.
  
 -Daniel


----------



## Mad Lust Envy

I think people are just too used to labeling anything Audio-GD as warm. I don't find the SA-31 to be much warmer than neutral, really. SLIGHTLY warm. I've heard warmer SS amps like Audio-GD's own NFB-5.

The Compass 2 (with the Sabre ES9018) is about as neutral as I've heard, so I think people need to start getting away from thinking Audio-GD is a warm focused company.


----------



## ManAtWork

mad lust envy said:


> I think people are just too used to labeling anything Audio-GD as warm. I don't find the SA-31 to be much warmer than neutral, really. SLIGHTLY warm. I've heard warmer SS amps like Audio-GD's own NFB-5.
> 
> The Compass 2 (with the Sabre ES9018) is about as neutral as I've heard, so I think people need to start getting away from thinking Audio-GD is a warm focused company.





Agreed, even with the so-called "warm setting", the sound is only not that agressive but isn't warm at all. At least not the common concept what we think 'warm' in audiophile.


----------



## BournePerfect

Looks like my SA-31SE is arriving today. I'll have some comments this weekend sometime after some good burn in. Will be using my Eximus and HD800s and T1 for comparisons...
  
 -Daniel


----------



## Balmoral

Any opinions on the amp yet Daniel?


----------



## BournePerfect

I like it-and it's for sale lol. Need $$ pronto to as my Leviathan deposit is finally due in the next week or two.
  
 I really like this amp with the HD800s. Very smooth, dark not warm, musical-all traits that seem to mesh well with the HD800s at this pricepoint. Seems to match pretty darn well with the T1 as well-but I still much prefer the Senn overall-even on my current mid-fi set up. Currently running the above from an SBT/EDO-->DP-1. Great soundstaging for an ss amp-which I expected as AGD's Diamond Differential series are well known for this. Probably better than even the P1-u which is also well regarded for it's ss abilities. Some other mid-fi amps I prefer this to, wrt the HD800 are: Auditor, Concerto, m-Stage (some regards, not others), pretty much every amp in my profile less than a grand. For the ss amps I've owned, I still prefer the Bryston and Luxman over this-which should be expected considering their cost. But I would argue this amp is more well rounded than either of those. It has more transparency than the P1-u, and definitely easier on the ears than the sometimes annoying highs of the BHA-1. Easy recommendation for an SS amp for the HD800s that won't annoy the ears like a LOT of cheaper ss amps seem to with the Senns. Hope that helps...
  
 -Daniel


----------



## Fearless1

bourneperfect said:


> I like it-and it's for sale lol. Need $$ pronto to as my Leviathan deposit is finally due in the next week or two.
> 
> I really like this amp with the HD800s. Very smooth, dark not warm, musical-all traits that seem to mesh well with the HD800s at this pricepoint. Seems to match pretty darn well with the T1 as well-but I still much prefer the Senn overall-even on my current mid-fi set up. Currently running the above from an SBT/EDO-->DP-1. Great soundstaging for an ss amp-which I expected as AGD's Diamond Differential series are well known for this. Probably better than even the P1-u which is also well regarded for it's ss abilities. Some other mid-fi amps I prefer this to, wrt the HD800 are: Auditor, Concerto, m-Stage (some regards, not others), pretty much every amp in my profile less than a grand. For the ss amps I've owned, I still prefer the Bryston and Luxman over this-which should be expected considering their cost. But I would argue this amp is more well rounded than either of those. It has more transparency than the P1-u, and definitely easier on the ears than the sometimes annoying highs of the BHA-1. Easy recommendation for an SS amp for the HD800s that won't annoy the ears like a LOT of cheaper ss amps seem to with the Senns. Hope that helps...
> 
> -Daniel


 
 Heh, I saw your ad and assumed you hated it. Good little write up and my thoughts exactly. I have heard better, but it is darn good for its price tier.


----------



## BournePerfect

Yes-if my budget was more limited, this would definitely be the amp I'd use for the Senns. Actually I'd probably still have an m-Stage too for it's somewhat lusher presentation at times. There is actually very little gear in my profile that I 'hated' (trust me-there's a few ), but saying this is the best HD800 amp I've heard under a grand is saying a lot-I've heard a ton of combos and it's pretty hard to find something that synergizes well with the HD800, without also masking some of it's strengths (m-Stage, I'm looking at you here). I feel that the SA-31SE balances that fine line of making the HD800 somewhat musical, but not at the expense of transparency, soundstage, details etc. I do feel the Auditor was more transparent and spacious-but it's presentation had a way of making the HD800 sound wonky at times across the frequency band-distractingly so at times that it outweighed my enjoyment of it otherwise, which is why I got rid of it-despite it's strengths.
  
 -Daniel


----------



## punit

Hi,
  
 I have the Schiit Lyr & recently purchased the Beyer T90's. I find the T90 treble a bit sharp with the Lyr & was considering buying a warmer amp which smooths the T90 treble but keeps the level of detail. Has anyone heard both ( the Lyr & SA31) & is the SA31 warmer / smoother sounding than the Lyr ?
  
 If you has not heard the SA31 & Lyr but has heard SA31 &  the Schiit Vanhalla / Asgard , can you please give your impressions. As the Lyr is supposed to be the brightest of the three Schiit amps. So if the SA31 is warmer / smoother than Vanhalla / Asgard then it will be definitely smoother than Lyr.
  
 Thanks


----------



## tim3320070

SA31 is only a warm amp in relation to other AGD gear, it's actually pretty neutral IMO. It will not dumb down treble.


----------



## eyal1983

I have an Etymotic ER4s (100 ohm resistance, 90db sensitivity)
 I am listening to music at fairly low volumes.
  
 Do you think that this kind of mW will destroy those IEMs ?
 or, are they safe ?


----------



## Ishcabible

Nope, I've used mine to drive IEMS quite often. Just remember to start at low gain and work your way up.


----------



## Vandal

mad lust envy said:


> Absolutely. The AKGs should sing off the SA-31. The AKGs were brilliant off the NFB5, and the SA-31 is much more powerful, so I expect even better performance.


 
  
 How is the SA-31SE with the HD650? I have the HD650 single ended, trying to decide between an NFB-6 and SA31. Appreciate your feedback


----------



## Clemmaster

vandal said:


> How is the SA-31SE with the HD650? I have the HD650 single ended, trying to decide between an NFB-6 and SA31. Appreciate your feedback


 
  
 Do you have any plans on going balanced with these?
 If yes -> NFB-6: less warm, should work better with the dark 650s.
 If no -> SA-31: works better single ended, no question.
  
 Note: I own the SA-31 and used to own the NFB-27 whose headphone amp section is of the NFB series (somewhere between the NFB-6 and Master-5/6/8).
 I consistently favored the SA-31 with all my headphones. This includes the Mad Dogs 3.0 *single ended*, which is the closest (in sound signature) to the HD-650. Even though it _should_ have worked better with the brighter NFB-27, it wasn't the case. The SA-31 is _that good_.
  
 Edit: forgot to say that _all my headphones_ = Hifiman HE-500, HE-4, HE-5LE, Fostex TH-600, AKG Q-701. They all are on the bright(ish) side of the force.


----------



## ManAtWork

vandal said:


> How is the SA-31SE with the HD650? I have the HD650 single ended, trying to decide between an NFB-6 and SA31. Appreciate your feedback




I use my SA-31 to drive both the HD650 and T1 very well. No worry about it.


----------



## Vandal

Manatwork, I refer to the synergy, not the ability to drive. How well do they synergize, both being warmish.

Clemmaster, I can't decide whether or not I'll go balanced with the hd650 over the next 2-3 yrs. I also have an RS1i which I'm sure I'll never balance, if that helps.


----------



## inter voice

I have just bought a brand new Audio GD SA-31 (not SA-31SE) Headphone amplifier at a bargain price.  After burning it in for more than 50 hrs I carried out an audition with three of my headphones, i.e.  Audeze LCD-X (with Toxic cable Silver Widow),  Senn HD800 (with Toxic cable Black Widow) and Hifiman HE-500 (with Toxic cable Black Widow).  I was disappointed by the overall performance of this SA-31 as it is not ear friendly when compared with my other three headphone amplifiers, i.e. Yulong A18; Fidelity Audio HPA-200SE and Hifiman EF-5 (modded – see this link:  http://www.head-fi.org/t/711004/hifiman-ef-5-headphone-amplifier-mods-and-rolls).
  
 From my knowledge I have the feeling that it should not be the fault of the circuit design or the components being used.  I suspect that the output impedance of SA-31 might be too low as I found it did not perform well with high impedance headphones.  The music was laid back and though it appeared to have more space I found that it was unreal and artificial. The music was not at all three dimensional.
  
 With that in mind I inserted two 33 ohm resistors in series to the L and R of the headphone output socket with a view to adjusting the output impedance.  Well, as I have expected the result is really excellent.  For best performance I put the gain to High and it performs much better than using Low gain setting.  The music is cleaner, with better sound staging and with better musical separation.  The artificial space has disappeared.  I have tried Warm 1 and Warm 2 settings but IMHO I still prefer without any warmth being added.  Now the SA-31 performs almost the same as Yulong A-18 and Fidelity Audio HPA-200SE which cost almost double the price.
  
 I have uploaded two photos to show how to add the two 33 ohm resistors for reference.  If you have tried it out you may wish to confirm if my finding is correct.


----------



## rocksteady65

> "From my knowledge I have the feeling that it should not be the fault of the circuit design or the components being used.  I suspect that the output impedance of SA-31 might be too low as I found it did not perform well with high impedance headphones.  The music was laid back and though it appeared to have more space I found that it was unreal and artificial."


 
  
 1. Both of your Planar-Magnetics are Low-Impedance. So, exactly what Headphones are you referring to? 
  
 2: A low impedance output should be beneficial to Any Headphone, not just low impedance types. Inserting a 33 Ohm resistor into the signal should not- theoretically at least- bring any improvements to sound quality. And it certainly makes no sense that it should impart a somewhat Laid-back quality to the music. In fact it should be the exact opposite...
  
 Best,
  
 Leonel


----------



## Utopia

In my experience the SA-31 needs plenty of burn-in, more so than any other amp, DAC or headphone I've owned. Perhaps the resistors are helping that process along (in addition to changing the output impedance and how the amp interacts with headphones)?


----------



## inter voice

rocksteady65 said:


> 1. Both of your Planar-Magnetics are Low-Impedance. So to what exact Headphones are you referring to?


 
 HD-800.
  
 Irrespective of what the theory are, my ears told me that there are actual improvements, in particular, to HD-800 after adding the 33 ohm.


----------



## i019791

inter voice said:


> HD-800.
> 
> Irrespective of what the theory are, my ears told me that there are actual improvements, in particular, to HD-800 after adding the 33 ohm.


 
 There are similar opinions for 43 ohm of the Sennheiser HDVD800, e.g.:
  
 http://www.head-fi.org/t/605444/sennheiser-hdvd800-headphone-amplifier/1830#post_10174212


----------



## inter voice

I have asked Kingwa on the same question and here is his reply:
  
*"Series the resistors will increase the output impedance, maybe the bass is less   cause the high and mid become more than bass. But in the design, the SA31 is except *_(may be a typo and should be "expected")_* sound warm and smooth , not neutral." *
  
That might be the reason of having better sound as I can hear clearer mid range and highs, but the bass has not reduced though.
  
IMHO the SA-31 sounds better to my ears with the resistors put in series but that could be my preference only.


----------



## nigeljames

Strange that it is the low impedance causing the poor sound with the HD800's because I love my Master-6 ( 1ohm output impedance) with the HD800's.
  
 Interesting solution though.


----------



## inter voice

nigeljames said:


> Strange that it is the low impedance causing the poor sound with the HD800's because I love my Master-6 ( 1ohm output impedance) with the HD800's.
> 
> Interesting solution though.


 
 Well I am not saying SA-31 is not good.  When I first heard the music from the SA-31 it was quite alright to my ears.  As I have other three headphone amplifiers I have the benefit of A/B testing them one by one in minute details using three different headphones, i.e. HD-800; LCD-X and HE-500.  My prefer headphone amplifier in its order is Yulong A18; Fidelity Audio HPA-200SE; Hifiman EF-5(modded) and then SA-31.  BUT after adding the series resistor the SQ of SA-31 has changed and now it almost performs the same as Yulong A18.  As to the headphones I prefer HD-800 for classical music while LCD-X for jazz and vocals.   HE-500 is not to my liking.
 As I mentioned before it is only my personal preference.


----------



## JWahl

inter voice said:


> Well I am not saying SA-31 is not good.  When I first heard the music from the SA-31 it was quite alright to my ears.  As I have other three headphone amplifiers I have the benefit of A/B testing them one by one in minute details using three different headphones, i.e. HD-800; LCD-X and HE-500.  My prefer headphone amplifier in its order is Yulong A18; Fidelity Audio HPA-200SE; Hifiman EF-5(modded) and then SA-31.  BUT after adding the series resistor the SQ of SA-31 has changed and now it almost performs the same as Yulong A18.  As to the headphones I prefer HD-800 for classical music while LCD-X for jazz and vocals.   HE-500 is not to my liking.
> As I mentioned before it is only my personal preference.


 
 That is an interesting finding given most people find they prefer the HD800 with a lower output impedance.  However, as King-wa stated, the artificial sense of space is by design.  I had the HD800 and the SA-31 before and felt it was an odd match with it as well but not necessarily bad though.  I moved to a Burson Soloist after that, and preferred it with the HD800's.  
  
 If you have a chance to listen to the Soloist, you may like it based on what you've said.  I felt the Soloist specifically had a more realistic presentation of soundstage and imaging of instruments.


----------



## Vandal

clemmaster said:


> Do you have any plans on going balanced with these?
> If yes -> NFB-6: less warm, should work better with the dark 650s.
> If no -> SA-31: works better single ended, no question.
> 
> ...


 
  

 I might go balanced, but I can't stomach the cost of balanced HD 650 cables except these: http://www.amazon.com/Upgrade-Version-balance-ZY-002-2-5M/dp/B00A2QJLY8/ref=sr_1_1?ie=UTF8&qid=1399695912&sr=8-1&keywords=sennheiser+HD650+xlr+cables
 What do you think?
  
 Also, I have an RS1i, which would be harder to balance, given that I'd need to ship them to the person doing the mod. Also this leaves me less flexibility if I'm travelling, since I couldn't lug my balanced rig with me.
  
 Kingwa only says the NFB-6 is slightly more neutral (note the newer version is a bit warmer based on user feedback), while the SA31SE is more musical. My only worry is they will make the HD650's bass bloat more, and then I can no longer use it for metal/rock etc. Any comments on that?


----------



## tim3320070

vandal said:


> I might go balanced, but I can't stomach the cost of balanced HD 650 cables except these: http://www.amazon.com/Upgrade-Version-balance-ZY-002-2-5M/dp/B00A2QJLY8/ref=sr_1_1?ie=UTF8&qid=1399695912&sr=8-1&keywords=sennheiser+HD650+xlr+cables
> What do you think?
> 
> Also, I have an RS1i, which would be harder to balance, given that I'd need to ship them to the person doing the mod. Also this leaves me less flexibility if I'm travelling, since I couldn't lug my balanced rig with me.
> ...


 
 I am sure you're aware that you can reterminate both those headphones for very little (under $20 shipped)- they are both 4 wire cables (Grado is more than 4 but easy).
 It is easier than you think unless you feel it has to be magic wire rather than stock.
 SA31 will no add bloat to anything, only a bit more warm than neutral from my experience.


----------



## Vandal

tim3320070 said:


> I am sure you're aware that you can reterminate both those headphones for very little (under $20 shipped)- they are both 4 wire cables (Grado is more than 4 but easy).
> It is easier than you think unless you feel it has to be magic wire rather than stock.
> SA31 will no add bloat to anything, only a bit more warm than neutral from my experience.


 
  
 Where can I get them reterminated for that price? Would be wonderful if you could let me know.


----------



## tim3320070

By your own hand with solder gun and solder and a little research.


----------



## FauDrei

vandal said:


> Where can I get them reterminated for that price? Would be wonderful if you could let me know.




See how to DIY it here.


----------



## CJG888

Has anybody else tried the SA-31 with the Beyer DT-48e?

IMO, a great combination for vocal and choral (tremendous transparency and lack of grain).


----------



## BrainFood

is it possible to use a universal remote with this amp?


----------



## Utopia

brainfood said:


> is it possible to use a universal remote with this amp?


 
  
 It doesn't seem to be possible with an ordinary Logitech remote or similar. There's an old thread about Audio GD remotes here: 
 http://www.head-fi.org/t/594569/audio-gd-ir-remote-programming-nfb10se


----------



## Utopia

Reading this thread I realized there isn't a whole lot of information about how the amp actually sounds, especially compared to other amps.
  
 My own very, very brief impressions:
  
 Compared to the M-Stage, I found the SA-31 faster, brighter (neutral?), with a larger soundstage and much more powerful, yet controlled, bass. I preferred the M-Stage with Denons, but have preferred the SA-31 with everything else (particularly HE-500, T1).
  
 Compared to the Bottlehead Crack, obviously the SA-31 is much, much better with the HE-500s. In fact, I find that to be a very good, highly recommended match. With the Beyerdynamic T1s I prefer the Crack. It sounds a little bit more open, a little bit more detailed, but still in a warm-ish, fluid way. Still I sometimes leave the T1s plugged into the SA-31 for a couple of days and find that I enjoy it a lot. Again the bass is very powerful and controlled, and the upper treble a little bit easier on the ear (the upper treble can get tizzy with the Crack + T1 for me).
  
 Overall, I think the SA-31 a very versatile amp, brighter and faster and more dynamic than the M-Stage, but still a sound with great body and sweet highs.


----------



## BrainFood

> Originally Posted by *Utopia* /img/forum/go_quote.gif
> 
> It doesn't seem to be possible with an ordinary Logitech remote or similar. There's an old thread about Audio GD remotes here:
> http://www.head-fi.org/t/594569/audio-gd-ir-remote-programming-nfb10se


 
 Sorry, didn't notice your reply.  Were you able to try out an apple remote?


----------



## Utopia

brainfood said:


> Sorry, didn't notice your reply.  Were you able to try out an apple remote?


 
  
 Yes, I did. It didn't have any effect on the SA-31, which is good since I'm using the remote with my Concero DAC.


----------



## tim3320070

utopia said:


> Reading this thread I realized there isn't a whole lot of information about how the amp actually sounds, especially compared to other amps.
> 
> My own very, very brief impressions:
> 
> ...


 
 Depending on the amount of hours you have on it, I find things change a bit with more use- particularly the openness and treble smoothness on the several AGD amps I have owned/own.


----------



## Mad Max

Plenty of encouraging feedback in this thread, and I like that some of you compared the amp to the M-Stage which is helpful.  Still no SA-31 versus a C-2 variant?


----------



## conquerator2

mad max said:


> Plenty of encouraging feedback in this thread, and I like that some of you compared the amp to the M-Stage which is helpful.  Still no SA-31 versus a C-2 variant?


 
 Well, this is the only piece of info I've found, courtesy of MLE, from the Compass2 thread:
  
 "I wouldn't give up my Compass 2 for any other amp/dac in their price range. Hell, I downgraded from the SA-31, and I'm perfectly content with the Compass 2."
 He also said [but for some reason I can't find that anymore] that the C2's midrange might be a smidge more refined.
 The SA-31 is bit more musical and warmer it seems.
  
 That's all I got.


----------



## Clemmaster

The SA-31 worked better for me than the built-in amp in my NFB-27 - which is between a NFB-6 and Master-6. The Compass 2 is probably not up to par with the NFB so even less so with the SA-31.
That's with Hifiman headphones which benefit from a warmer amp (SA). 
MLE likes warm/dark headphones and has a strong bias against more expensive gears, so I'm not surprised the compass worked better for him.


----------



## conquerator2

clemmaster said:


> The SA-31 worked better for me than the built-in amp in my NFB-27 - which is between a NFB-6 and Master-6. The Compass 2 is probably not up to par with the NFB so even less so with the SA-31.
> That's with Hifiman headphones which benefit from a warmer amp (SA).
> MLE likes warm/dark headphones and has a strong bias against more expensive gears, so I'm not surprised the compass worked better for him.


 
 FYI, Compass 2 has a very similar amp to the NFB-28's [which is a step down from the NFB-27] which has a similar amp section to the NFB-6. The C2 and SA-31 iare built around a single ended design while the NFB-27 & 28 are built around a balanced design so they're not on equal footing if you compare them SE. Also, between NFB-6 and Master-6, that's a pretty broad range, isn't it? 400 vs 1500 is quite a jump there.
 Also, I am not sure to what degree HFM benefits from a warmer amp [or source] but I am about to find out. Some say the C2 is slightly warm, others say it's slightly bright and some say it's neutral with equal bass and treble extension... I for instance found the HE-6 w/ a warmer source a bit dull [but still great, don't get me wrong], hence going with a neutral-ish source this time around.
 Also HFM 4, 5LE & 6 are the three hardest to drive headphones around [pretty much], not sure to what degree it is warmness or also the raw power output where the 500/560 or 400/400i isn't nearly as demanding.
 Well, I'll find out soon but it seems the difference between gear is often exaggerated around here... 
 Just saying and IMO.
  
 Not in disagreement, just pointing some things out


----------



## tim3320070

conquerator2 said:


> .
> it seems the difference between gear is often exacerbated (exaggerated) around here...


 
 x10,000,000,000


----------



## .Sup

conquerator2 said:


> Well, I'll find out soon but it seems the difference between gear is often exaggerated around here...




As is power requirement for certain phones...


How do the buttons on this amp work in terms of convenience compared to a big volume knob? Seems like it would take a while to reach preferred volume and constant pressing/holding might make the buttons not last as long as a potentiometer.


----------



## conquerator2

.sup said:


> As is power requirement for certain phones...
> 
> 
> How do the buttons on this amp work in terms of convenience compared to a big volume knob? Seems like it would take a while to reach preferred volume and constant pressing/holding might make the buttons not last as long as a potentiometer.


 
 Hard to say, I always used a potentiometer [either analogue, or just as a digital volume control "knob"]


----------



## Clemmaster

I was comparing NFB-27 balanced vs SA-31 single ended (with NFB-27 as a DAC, in SE) so that reinforce my point.
In the end, all that matters is that you're happy.


----------



## conquerator2

clemmaster said:


> I was comparing NFB-27 balanced vs SA-31 single ended (with NFB-27 as a DAC, in SE) so that reinforce my point.
> In the end, all that matters is that you're happy.


 
 Not a matter of happiness [I have not heard the C2 yet obviously].
 Just pointing some things out, it's not always black and white and that the differences tend to be smaller in reality than expected 
	

	
	
		
		

		
			





 
  
 I am sure we can agree that the SA-31 is a great amp, let's leave it at that. I agree with your points just lowering the magnitude.


----------



## conquerator2

I think I am gonna go with the SA31SE for my HE-560s...
 The Compass2, being both a great DAC and amp... Well, DAC is great but amp is slightly edgy, possibly.
 The warmer SA31SE should fit pretty well, plus allow for more headroom with weaker sources :]
 I'll be using the C2 DAC meanwhile, unless the NFB7 appears in the classifieds for an amazing price.


----------



## shayson1357

as far as I know the AGD SA-31SE is an amp only, it doesn't have a DAC, right ?


----------



## Clemmaster

Nope.


----------



## shayson1357

how so, the website states that this product is a "*D**iscrete Preamp **/ Headphone amp" O.o*
 PS. I was emailing kingwa about purchasing this amp but I haven't replied yet, I was thinking that I wouldn't have enough cash to buy a DAC if I got this. so confusing -_-


----------



## conquerator2

shayson1357 said:


> how so, the website states that this product is a "*D**iscrete Preamp **/ Headphone amp" O.o*
> PS. I was emailing kingwa about purchasing this amp but I haven't replied yet, I was thinking that I wouldn't have enough cash to buy a DAC if I got this. so confusing -_-


 
 Yes, it is a discreet amp and preamp but not a DAC [digital to analogue converter].
 If you want an all-in-one device, look at the NFB11, NFB15, NFB 10.33, Compass2, NFB28, NFB27 or Reference 10.32 :}


----------



## inter voice

shayson1357 said:


> how so, the website states that this product is a "*D**iscrete Preamp **/ Headphone amp" O.o*
> PS. I was emailing kingwa about purchasing this amp but I haven't replied yet, I was thinking that I wouldn't have enough cash to buy a DAC if I got this. so confusing -_-


 
 I bought my SA-31 from Frank of Toxic cable at a bargain price (cheaper than from Kingwa direct). PM Frank and ask for a price.  I think he still got a few units (they are brand new).


----------



## conquerator2

inter voice said:


> I bought my SA-31 from Frank of Toxic cable at a bargain price (cheaper than from Kingwa direct). PM Frank and ask for a price.  I think he still got a few units (they are brand new).


 
 But those are SA31, not SA31SE, correct?


----------



## shayson1357

PM'd him about 3 hours ago, I'll see what he has to say


----------



## inter voice

conquerator2 said:


> But those are SA31, not SA31SE, correct?


 
 You are right it is a SA31 and not 31SE.
  
 BUT I have asked Kingwa and he said the difference between 31 and 31SE is just on the volume control.  The SQ of both are the same.  You can upgrade 31 to 31SE by changing two boards costing only USD 30 in total (but excluding postage from China). The swap is easy and no soldering is needed.
  
 TBH the volume control of 31 is quite okay to me. I found nothing wrong with it and that is why I did not change the volume control pcb.


----------



## conquerator2

inter voice said:


> You are right it is a SA31 and not 31SE.
> 
> BUT I have asked Kingwa and he said the difference between 31 and 31SE is just on the volume control.  The SQ of both are the same.  You can upgrade 31 to 31SE by changing two boards costing only USD 30 in total (but excluding postage from China). The swap is easy and no soldering is needed.
> 
> TBH the volume control of 31 is quite okay to me. I found nothing wrong with it and that is why I did not change the volume control pcb.




Good for you 
Mine is already ordered and paid. Should be shipping early next week.
With 2 1/4 Neutrik headphone outputsand a custom 6/26 gain board


----------



## Clemmaster

inter voice said:


> You are right it is a SA31 and not 31SE.
> 
> BUT I have asked Kingwa and he said the difference between 31 and 31SE is just on the volume control.  The SQ of both are the same.  You can upgrade 31 to 31SE by changing two boards costing only USD 30 in total (but excluding postage from China). The swap is easy and no soldering is needed.
> 
> TBH the volume control of 31 is quite okay to me. I found nothing wrong with it and that is why I did not change the volume control pcb.


 
 It is quite slow I found.
 The new one is much faster (I owned both).


----------



## shayson1357

these are the specs for 10.33 amp/dac:
 9950MW /  25 ohm 
 5950MW /  50 ohm 
  3300MW  /  100 ohm
 1150MW / 300 ohm
 590MW  /  600 ohm

 do you think the SE-31SA is better for the HE-500 headphones or would this one be a better deal considering that I have no standalone DAC right now ?


----------



## conquerator2

shayson1357 said:


> these are the specs for 10.33 amp/dac:
> 9950MW /  25 ohm
> 5950MW /  50 ohm
> 3300MW  /  100 ohm
> ...


 
 NFB10.33 is better for you. Additionally, if you want something less warm and more neutral, stretch for the NFB28


----------



## shayson1357

can't do that much 
 audio-gd already wants 85$ for shipping and another 80 for handling fees( What is that ? )


----------



## shayson1357

anyone know where I can buy the SA-31SE amp(or any other Audio-gd product) using a visa card ? no paypal or wire transfer.


----------



## conquerator2

shayson1357 said:


> anyone know where I can buy the SA-31SE amp(or any other Audio-gd product) using a visa card ? no paypal or wire transfer.


 
 Audio-GD allows that but there's a 40$ transfer fee.
 No idea about others.


----------



## shayson1357

excuse me if I sound newbish, but I don't see a checkout button or cart or anywhere I can use my card for that matter, when I contacted kingwa they replied with :
  (do you accept Visa payment ? since paypal doesn't allow accounts from my country   )----------We have the Hongkong USD account, but the handling charge is quite costly, usually need USD55 .
 but I think they didn't quite understand what I was saying(I asked a few other questions before that one)
 and after that Q&A they sent
 {

*Audio-gd Quote List*1,Please confirm the items if exact as your order .   The SUM had include shipping cost and Paypal handling charge. Please inform customer name, address and Tel.  for the shipping.US Dollar Account Numbers：*◎ Bank of China (Hong Kong) Limited   Mong Kok Branch
 589 Nathan Road ,  Mong Kok  , Kowloon
 Account Name: HE QINGHUA

 Account Number:  01258692103335
 SWIFT/BIC-CODE:  BKCHHKHH*
 }
 along with the order number and purchase order list.....etc...etc...
 and that got me really confused, can anyone tell me what was going on


----------



## inter voice

I believe what Kingwa meant is you can use Bank transfer to the stated account in Hong Kong, BUT the bank will impose additional charge for Kingwa to receive the money in China. This will be reflected when you proceed with the bank transfer and such charge will be USD 55.  I hope my interpretation is correct.
  
 In the past I paid Audio GD by Paypal and it seems that Paypal cannot be used now.  As to using credit card payment I am afraid China does not accept visa cards except their own Credit cards issued by banks belonging to China.


----------



## conquerator2

inter voice said:


> I believe what Kingwa meant is you can use Bank transfer to the stated account in Hong Kong, BUT the bank will impose additional charge for Kingwa to receive the money in China. This will be reflected when you proceed with the bank transfer and such charge will be USD 55.  I hope my interpretation is correct.
> 
> In the past I paid Audio GD by Paypal and it seems that Paypal cannot be used now.  As to using credit card payment I am afraid China does not accept visa cards except their own Credit cards issued by banks belonging to China.


 
 Yep sounds right. They accept Paypal or bank transfer with charges ranging from 40 - 60$ it seems.


----------



## shayson1357

I never bought anything with wire transfer before, I mean..... is it safe ? 
	

	
	
		
		

		
		
	


	



 would it still be worth it to pay approximately 660$ for the SA-31SE because that would be the same price for the LaFigaro 339 with shipping and everything 
	

	
	
		
		

		
		
	


	




.


----------



## conquerator2

shayson1357 said:


> I never bought anything with wire transfer before, I mean..... is it safe ? :confused_face_2:
> 
> would it still be worth it to pay approximately 660$ for the SA-31SE because that would be the same price for the LaFigaro 339 with shipping and everything  .




I think it won't cost you more than 600$... It cost me 560$ with paypal fees.


----------



## shayson1357

here's what Kingwa replied with:
 Dear Sir,
 You can transmit the money to our bank account
*◎ Bank of China (Hong Kong) Limited   Mong Kok Branch
 589 Nathan Road ,  Mong Kok  , Kowloon
 Account Name: HE QINGHUA

 Account Number:  01258692103335
 SWIFT/BIC-CODE:  BKCHHKHH*
 Total price is USD620.
 Kingwa


 Does he mean that I'd have to wire 620 dollars(AND pay the 60$ fee at the bank ? ) so it would be 680$ 
	

	
	
		
		

		
		
	


	




 But, in their first email reply I saw that it costs only 485$ without anything:
   
*Audio-gd Quote List*1,Please confirm the items if exact as your order .   The SUM had include shipping cost and Paypal handling charge. Please inform customer name, address and Tel.  for the shipping.US Dollar Account Numbers：*◎ Bank of China (Hong Kong) Limited   Mong Kok Branch
 589 Nathan Road ,  Mong Kok  , Kowloon
 Account Name: HE QINGHUA

 Account Number:  01258692103335
 SWIFT/BIC-CODE:  BKCHHKHH*
  3,We will declare the items value low to *USD150  *(exclude shipping cost)   on the invoice for customs, if you want declare different value please inform .*Order No.*2014071109*Lead Time*4  Workdays*Customer Full Name*　*Customer Telephone No.*　*Customer Address*　*SUM (USD)  *（Include USD55 handling charge)*$620.0**Purchased Order List**Items**Quantity**Price（USD）**Voltage ＆ Power Cable**Note*SA-31SE1485?Audio-gd 10th anniversary ,5% OFF　　　　　　　　　　*Shipping cost*　80　Shipping by DHL*Power cable number link:* http://www.audio-gd.com/Cable%20Type.jpg


----------



## conquerator2

shayson1357 said:


> here's what Kingwa replied with:
> Dear Sir,
> You can transmit the money to our bank account
> 
> ...




That is the final price, it already includes everything even all the charges.


----------



## inter voice

Well, if you are in the UK why not PM Frank of Toxic Cables.  I think he still has a few SA31 in stock at a bargain price.  The SQ of SA31 and 31SE are exactly the same except that SE has faster volume control.  Actually I bought one from Frank.
 If you are in the US ask for the shipment price and I think it should be still cheaper than directly from Kingwa due to high surcharges.


----------



## conquerator2

inter voice said:


> Well, if you are in the UK why not PM Frank of Toxic Cables.  I think he still has a few SA31 in stock at a bargain price.  The SQ of SA31 and 31SE are exactly the same except that SE has faster volume control.  Actually I bought one from Frank.
> If you are in the US ask for the shipment price and I think it should be still cheaper than directly from Kingwa due to high surcharges.




There're a few more differences like higher gain, OCC cables and 20 more volume steps.
But if it is like 100+$ cheaper I'd go for it.


----------



## inter voice

conquerator2 said:


> There're a few more differences like higher gain, OCC cables and 20 more volume steps.
> But if it is like 100+$ cheaper I'd go for it.


 
 Yes, with 31SE on high gain setting the actual "gain" is higher than 31.  However you only need this when your input signal is very weak. For me I always use Low gain setting and High setting is never used.
 Frank of Toxic cable told me that all the internal wirings of his stocks were changed with OCC Toxic Cables.
 31SE has 100 steps of volume control instead of 80 in 31, and the volume control curve is better, i.e. when you turn the volume up the gain is not linear and is more fine tune at low volume.  The volume o/p will increase rapidly at the high volume end.  
 As to the price PM Frank and I think the overall price should be cheaper by more then USD 100. If you can send the money by Bank transfer Frank can give you a better price as there is no surcharges on him (that is what I did when I bought the 31 from Frank).


----------



## shayson1357

PM'ed him twice, and now sent an email to " info.toxic.cables@gmail.com "


----------



## inter voice

Frank is very busy in making cables and may take sometime for him to reply.
  
 PM Frank in the Toxic Cable Appreciation thread and he will reply you more speedy.


----------



## conquerator2

The SA31SE is no longer on their website 
	

	
	
		
		

		
		
	


	



 Strange it is... I suppose I should be grateful I snatched mine awhile back but I hope Kingwa isn't phasing this beast out [though he very well might be 
	

	
	
		
		

		
		
	


	




]


----------



## Clemmaster

conquerator2 said:


> The SA31SE is no longer on their website :blink:
> Strange it is... I suppose I should be grateful I snatched mine awhile back but I hope Kingwa isn't phasing this beast out [though he very well might be  ]


Kingwa told me a long time ago the SA series was not do popular and he would discontinue it. It started with the DACs and now the amp.

The Master 7 is actually more "musical" than the SA-2. Go figure...


----------



## bob77

Does anyone know if the SA-31SE comes with acss input ?
 I found pictures of a version with acss (which is not the one of audio gd website) but it is labelled "output", and that sound a bit unusual. I would expect to see input.


----------



## sayh

bob77 said:


> Does anyone know if the SA-31SE comes with acss input ?
> I found pictures of a version with acss (which is not the one of audio gd website) but it is labelled "output", and that sound a bit unusual. I would expect to see input.


 
 SA-31 series is a single ended diamond diffrential design amp/preamp,  with 5 rca inputs & 3 rca preamp outputs.
 There is no acss connection on it. 
 What you saw should be the nfb6 which is a balanced design amp/preamp, with acss input and preamp output.
 They share the same front panel design.


----------



## bob77

thank you for your help. I'am a bit amazed because I thought that the nfb6 had xlr connection, and what I saw had not. Here is the picture of what is supposed to be the sa32se

 By the way, you are right for the front face which looks identical to the nfb6.


----------



## Vandal

The NFB6 does have XLR connections. Here is a shot of mine.


----------



## rnsto

Vandal could you tell your impressions on the NFB6?


----------



## i019791

bob77 said:


> thank you for your help. I'am a bit amazed because I thought that the nfb6 had xlr connection, and what I saw had not. Here is the picture of what is supposed to be the sa32se
> 
> By the way, you are right for the front face which looks identical to the nfb6.


 
 This is the Audio gd C-2:
  
 http://www.audio-gd.com/Pro/Headphoneamp/C-2Class%20A/C2classAEN.htm


----------



## bob77

i019791 said:


> This is the Audio gd C-2:
> 
> http://www.audio-gd.com/Pro/Headphoneamp/C-2Class%20A/C2classAEN.htm


 
 This new C-2 has 2 sets of acss connector. The picture I show has only one. Audio-GD should work hard to be so difficult to follow ...


----------



## richbass

Is the SA-31SE Discontinued ?


----------



## shayson1357

richbass said:


> Is the SA-31SE Discontinued ?


 
 yes, a few months back.... you "might" find one used but I'd recommend other options since nowadays there are lots of options to choose from.... bear in mind though, amps are not just about watts


----------



## richbass

shayson1357 said:


> yes, a few months back.... you "might" find one used but I'd recommend other options since nowadays there are lots of options to choose from.... bear in mind though, amps are not just about watts


 

 Ah. What other options are well worth it ?


----------



## shayson1357

richbass said:


> Ah. What other options are well worth it ?


 
 depends on what you're really after, just like everything in life 
	

	
	
		
		

		
		
	


	



 but I think it would be better if you'd post such a question on the thread of the specific headphone you want to drive so as not to derail this one.


----------



## conquerator2

Bump.
 I think it is a shame they discontinued the SA31SE.
 I've been very happy with my unit so far, driving everything I've thrown at it [currently my HE-560].
 Great power and great sound, transparent but warmish [on 0, warmer on warm 1 & 2].
 Hardly anything to complain about [minor nitpick is that it is single-ended only, but I don't care].
 If it was still available, it'd be one of the best candidates in the ~500$ range.
 Not looking to get rid of it in the near future and I consider it one of my best buys.


----------



## inter voice

Yes I totally agreed that SA31 is a great headphone amp in the price range.  If someone still wish to have one I believe Frank of Toxic Cable should still have a few in stock.  I bought my SA31 from Frank at a bargain price. PM him if anyone is interested on this great amp. Good luck.


----------



## conquerator2

Audiophonics still have it in stock so if anyone is interested buy it from there


----------



## Synthax

How SA31SE or NFB6 comapre to Violectric V200 or other 1000$ price range amps? Thank you for your help


----------



## Utopia

I've had the SA31 and currently have a Gustard H10, which is supposed to be very similar ot the V200. I never had the amps side by side, so it's difficult to compare them, but the SA31 definitely had a larger soundstage and sounded a little bit leaner and faster IMO. The H10 is warmer, more intimate, with great tone and musicality, but also a bit closed-in compared to the SA31.


----------



## conquerator2

The new audio-gd 'budget' amp - http://audio-gd.com/Pro/Headphoneamp/NFB1AMP/NFB1AMPEN.htm
 As well as a super budget one - http://audio-gd.com/Pro/Headphoneamp/NFB3AMP/NFB3AMPEN.htm


----------



## oneofthem

greetings gents
  
 looking to obtain sa31/se
  
 agd released new class a acss amps based on master))
  
 pm please if decide to sell your sa31
  
 thank you in advance
  
 cheers


----------



## borrego

I just bought a SA-31SE from audio-gd's France reseller (220V version). With the on going EUR-USD exchange rate, it costs almost the same as buying from audio-gd originally, but including shipping.
  
 I was also considering the C2 11th anniversary edition, but decided to try the last remaining Toshiba BJT diamond differential amp from audio-gd while it can still be found. One might feel regret not doing so as an upcoming amp from another manufacturer with similar topology will cost 110% more to the SA-31SE.


----------



## conquerator2

borrego said:


> I just bought a SA-31SE from audio-gd's France reseller (220V version). With the on going EUR-USD exchange rate, it costs almost the same as buying from audio-gd originally, but including shipping.
> 
> I was also considering the C2 11th anniversary edition, but decided to try the last remaining Toshiba BJT diamond differential amp from audio-gd while it can still be found. One might feel regret not doing so as an upcoming amp from another manufacturer with similar topology will cost 110% of the SA-31SE.




Good choice! I love mine.
What upcoming amp are you talking about?


----------



## borrego

conquerator2 said:


> Good choice! I love mine.
> What upcoming amp are you talking about?


 
  
 I don't feel like stating the brand/model directly because I was on the waiting list buying that amp. That amp shall be Class A all the way, and with an outboard power supply. It was just the lack of low gain option of that amp turned me away. I do think the relay-based volume control of the SA-31SE will have an edge on channel separation though.
  
 The SA-31SE will be my "power" headphone amp to drive my HE-500, or may be the T1. For all other higher sensitivity headphones I am extremely satisfied with my EPA-007.


----------



## conquerator2

borrego said:


> I don't feel like stating the brand/model directly because I was on the waiting list buying that amp. That amp shall be Class A all the way, and with an outboard power supply. It was just the lack of low gain option of that amp turned me away. I do think the relay-based volume control of the SA-31SE will have an edge on channel separation though.
> 
> The SA-31SE will be my "power" headphone amp to drive my HE-500, or may be the T1. For all other higher sensitivity headphones I am extremely satisfied with my EPA-007.




Ok. Only the Cavalli comes to my mind


----------



## borrego

conquerator2 said:


> Ok. Only the Cavalli comes to my mind




I meant to say 110% more expensive than the SA-31SE...


----------



## borrego

Just received my SA-31SE in the office. Surprising, it comes with the optional aluminum remote control. It could the aluminum remote is a standard accessory from the French reseller.
  
 First thing I do is opening up the case and remove all the "Input Short" jumpers behind the input relays. I will be connecting the SA-31SE to my NFB-1 in parallel to the EPA-007 at home. I don't want the input short jumpers to affect my EPA-007.
  
 I am just doing some initial listening with my SR325e in the office. The overall tone is very similar to my 5751 + 832A tube amp. The SA-31SE does resolve better compare to the tube amp. The treble is beautiful, bass is a bit light (but does extend very good). I shall burn in longer period and see if bass will improve.
  
 Overall I am happy with my purchase.


----------



## CJG888

Try it with the DT48e, if you can find a pair. This is a fantastic combination for jazz and classical.


----------



## borrego

*A FIX SHOULD BE DONE FOR EVERY SA-31!!!*
  
I have owned the SA-31SE for a few days. While I like its sound, I do find a few problems with my unit:
  
1. The amp takes a long time to "warm up": I find it needs up to 2 hours to have its sound signature to settle down. And it is with my EPA-007 stacking over it
2. Even after warm up, it sounds lean. The bass and overall dynamic lack quite a bit
  
 I know the SA-31 circuit is base on the discontinued/earlier audio-gd SA100/SA100i/SA200 integration amp. I recall reading something before from audio-gd's Chinese DIY forum saying there is usage of temperature compensation transistors in the SA300 poweramp circuit design (the SA300 is the balanced version of the SA100/SA200). The temperature compensation transistors should be placed/pressed to the headsink shared by the output power transistor.
  
 I start looking at the SA-31 photos on audio-gd websit, and find the SA-31 also has a pair of this temperature compensation transistors (circled yellow below):
  

  
  
 Thus I suspect the problems I have the SA-31 is because of *improper contact* between the temperature compensation transistor and the aluminum back plate heatsink shared with the output power transistors.
  
 I come up with the following "Laundry Clip Fix" for my SA-31: a fix to press the temperature compensation transistor properly against the aluminum back plate. I use all plastic parts to make sure it won't short any circuit by accident.
  
 Step 1: Take out the plastic spings from a pair of laundry clips I have at home (these are laundry clips I bought from Ikea)


  
 Step 2: Find a pair long/sturdy piece of plastics serving as the "pressing levers". I cut off the tails of a pair of plastic forks I have at home.

  
 Step 3: Place all the parts I made to press/clamp the pair of temperature compensation transistors against the aluminum black plate. I apply glue between the plastic clips and the top of the black plate to make sure the clips stay put.

  
  
*Results after the fix:*
1. The amp now only needs about 20mins to "warm up" and have the sound signature stabilized.
2. More bass, and more dynamic sounding signature. My SA-31 finally sounds "properly".
  
 I strongly recommend all SA-31 owners to apply the fix.


----------



## Robert777

borrego said:


> *A FIX SHOULD BE DONE FOR EVERY SA-31!!!*
> 
> I have owned the SA-31SE for a few days. While I like its sound, I do find a few problems with my unit:
> 
> ...


 
 Thank you for the above post. The information is very useful but it is things like this that may make me return my SA-31SE when I receive it this week.
 I was really excited for my new amp but I am now a little apprehensive. I am rubbish with all kinds of DIY and I prefer things to work as intended from the start.
  
 Has anybody else had a similar experience?
  
 Cheers.


----------



## conquerator2

No. It is an awesome amp. No mods needed imo


----------



## Clemmaster

Yep. It's great. After all these years I still have mine and can't resolve to selling it...


----------



## borrego

robert777 said:


> Thank you for the above post. The information is very useful but it is things like this that may make me return my SA-31SE when I receive it this week.
> I was really excited for my new amp but I am now a little apprehensive. I am rubbish with all kinds of DIY and I prefer things to work as intended from the start.
> 
> Has anybody else had a similar experience?
> ...


 
  
 If you do not find any problem with your SA-31 then there is absolutely no need to worry. Just enjoy the amp.
  
 I am a DIYer and knowing the SA-31 has a really good circuit design just makes me want to make sure everything is rightly done so I can have it reaching its maximum potential. I actually considered buying the SA-31 circuit board from audio-gd's DIY shop and built my own SA-31 (http://item.taobao.com/item.htm?spm=a1z0d.6639537.1997196601.32.oqgKBR&id=520377979177). So I did do some research on the SA-31 circuit design and key assembling steps.


----------



## Robert777

conquerator2 said:


> No. It is an awesome amp. No mods needed imo


 
  
  


clemmaster said:


> Yep. It's great. After all these years I still have mine and can't resolve to selling it...


 
 Thank you. I am excited again. 
  
 Cheers.


----------



## Robert777

I received this amplifier a few days ago and I am very impressed.
 I purchased the last unit from a dealer in France and it also come with the remote control as standard.
 It also came with some circuit boards in bubble wrap which I have no idea what to do with.
 I am using my HP-A8C as a DAC, connected to the SA-31SE, feeding my Fostex TH900 and TH500rp headphones.
  
 I would say the Audio-gd amp adds a clarity, separation, detail and effortlessness to the sound.
 The improvements are only subtle, as I think they are with most things at this level, but they are welcomed.
 I now find myself getting drawn into the music much more than when running directly from the HP-A8C, which I still think is a beautiful product.
 The Audio-gd has me head banging, toe tapping and smiling before realising.
  
 Highly recommended.
  
 Cheers.


----------



## inter voice

borrego said:


> *A FIX SHOULD BE DONE FOR EVERY SA-31!!!*
> 
> I have owned the SA-31SE for a few days. While I like its sound, I do find a few problems with my unit:
> 
> ...


 
  
 Thank you for the finding and I have done similar mods to my SA-31 using metal clips and hard plastic pressing strips. Silver contact greese is applied between the 2 transistors and the heat sink to ensure best thermal transmissions.  It only took me 20 minutes to complete this simple task. I can confirm that now the SA-31 stabilizes much quicker with this mod being in placed.  Thanks.


----------



## heybaroo

I have to thank this thread - I've moved into head fi from regular hi fi as small spaces and small children have dictated drastic changes. I've been trying to replace a Cayin tube amp matched to Dynaudio bookshelves for a fraction of the cost and this thread led me to the SA-31. I found one on Gumtree, did a lot of research, and this thread was the tipping point. Thanks very much! I started out with my Jaycar Digitech/Brainwavz HM5/Fischer Audio FA-003 clones and thanks to another thread moved on to the Fischer FA-011s. They need some proper amping which this has in spades. I had the jumpers in for the FA-003 clones but with the FA-011s the jumpers are out and more detail is in as they are quite v-shaped in signature. Unbelievable combination for under AUD600! I'm using a Fiio X1 as the source with flac and some some lossy files and have almost approached my previous $5,000 setup soundwise...has anyone else tried this combination? I know both are a bit long in the tooth but I'm an analogue man at heart...
  
 Really good preamp as well - very, very impressive for the price point.
  
 Anyway, thanks again for helping me find this amp!


----------



## conquerator2

I still scratch my head as to why this baby was ever discontinued. I keep looking for a similarly priced amplifier to this day to outperform it, but it isn't easy


----------



## heybaroo

conquerator2 said:


> I still scratch my head as to why this baby was ever discontinued. I keep looking for a similarly priced amplifier to this day to outperform it, but it isn't easy




Hear hear... I'm thinking about upgrading my headphones (of course) and an going to hang on to the SA-31 as I think it should drive just about anything well... I've started doing a bit of research on the HE-6 and just read your review on it from a few years ago. How do you think the SA-31 would go driving it? On paper, it should be hope but I've read about people using 160W amps on them. Of course this is into 8 ohms and the SA-31 does 10W into 40 ohms... just curious.


----------



## heybaroo

Oops, fine,not hope...


----------



## conquerator2

heybaroo said:


> Hear hear... I'm thinking about upgrading my headphones (of course) and an going to hang on to the SA-31 as I think it should drive just about anything well... I've started doing a bit of research on the HE-6 and just read your review on it from a few years ago. How do you think the SA-31 would go driving it? On paper, it should be hope but I've read about people using 160W amps on them. Of course this is into 8 ohms and the SA-31 does 10W into 40 ohms... just curious.


 
 You're right, it technically should suffice.
 But with the HE6, you are better off with speaker amplifiers. They provide the most power and the HE6 really likes that.
 Again, can't know until you try and you can always get a cheap vintage speaker amp to suit them 
	

	
	
		
		

		
		
	


	



 Regardless, I would exercise caution when buying the HE6. It has the potential to reward you, but you have to commit it.
 I wouldn't buy the HE6 again for many reasons, power hungry being just one of them, though there are many happy owners with testimonials of brilliance


----------



## Clemmaster

The SA-31 is fine for any Hifiman planar except the HE-6. It sounds shrill with it.
  
 It's the only headphone that I preferred on the NFB-27 built-in amp, because it is more beefy (less "powerful" on paper, but it has a beefier power supply). For any other Hifiman, the SA-31 was my go-to amp.


----------



## conquerator2

It's been consistently my  go-to amp for every headphone. It's not dead-flat neutral, it has a certain character, or coloration that won't suit every headphone but it's a damn good and versatile amp that powers virtually anything. There's nothing quite like it on the market today IMO 
	

	
	
		
		

		
		
	


	



 Dunno what I'll buy when it breaks


----------



## borrego

heybaroo said:


> Hear hear... I'm thinking about upgrading my headphones (of course) and an going to hang on to the SA-31 as I think it should drive just about anything well... I've started doing a bit of research on the HE-6 and just read your review on it from a few years ago. How do you think the SA-31 would go driving it? On paper, it should be hope but I've read about people using 160W amps on them. Of course this is into 8 ohms and the SA-31 does 10W into 40 ohms... just curious.


 
  
 The circuit design of the SA-31 originated from the SA-100, which was an integrated speaker amp from audio-gd. So you can be sure the SA-31 has enough power to drive the HE-6.
  
 The SA-31 sounds "Shrill" not because it lacks power, but because its temperature compensation transistors were not touching the heatsink plate properly. See my "laundry clip" mod a few pages back for the fix.
  
 With the "laundry clip" fix in place, the SA-31 sounds like a good neutral, powerful tube amp.


----------



## heybaroo

Thanks folks, all of the above has just reinforced how happy am with this amp. It should pair up quite well and drive almost anything I am likely to own in the next several years, perhaps even the HE-6 with borrego's mod. Amazing purchase for AUD250. I have read that it has a real synergy with the HE-500, and I am very keen to hear a HD-650 with it as well...


----------



## Pharmaboy

Don't know if anyone is still following this thread, but I just have to weigh in on the Audio GD SA-31SE.
  
 I bought mine from a Head-Fi bud about 6 weeks ago, around the same time I got a new ZMF Ori. Those are incredible headphones that do everything rather differently & better than I'm used to. They sound spectacularly good through the SA-31SE. But oddly enough, the Ori made it harder to figure out what this amp can do (studying 2 unknown variables is harder than just one).
  
 I've been trying the Ori on other HP amps in house, and can confirm it's an amazing headphone, regardless of source. But it was only tonight that I finally listened to other headphones on the SA-31SE--2 inexpensive Chinese closed-back designs I've had for a number of months...I know their sound well, or thought I did.
  
 Listening to one of them now on the SA-31SE, and it's striking to hear this inexpensive-but-good headphone scale right up with the SA-31SE. For the first time with the Marantz MPH-2, I'm hearing richly detailed midrange, full of subtle positional nuances and great finesse in the sound of percussion. It sounds so good. Got the same basic result with the Yenona Adapter Free DJ headphones...they both sound like themselves, but greatly improved. I'll try the Philips Fidelio X2's tomorrow.
  
 Suddenly it's very clear that the SA-31SE is absolutely the equal of the Ori. Each produces great note separation, finesse, and detail, top to bottom, with zero brightness or "sheen." I have other amps that hit harder & a touch lower in the bass, and have somewhat more impactful dynamics overall. But I've never heard another amp even come close to the SA-31SE in the subtle sonic areas of soundstaging and microdynamics. For example, the SA-31SE is easily the best amp I've ever heard for percussion...all kinds of percussion.
  
 I am so lucky to have found this amp. BTW, my DAC is the equally superb Audio GD NOS 19. I'm guessing the SA-31SE has unusual synergy with this DAC.
  
 (life is good!)


----------



## Mike Nee

pharmaboy said:


> I've been trying the Ori on other HP amps in house, and can confirm it's an amazing headphone, regardless of source. But it was only tonight that I finally listened to other headphones on the SA-31SE--2 inexpensive Chinese closed-back designs I've had for a number of months...I know their sound well, or thought I did.
> 
> (...)
> 
> ...


 
  
 Hi, have you heard theirs NFB-1AMP? Or maybe you know of any comparison between SA31SE and NFB-1AMP?
  
 On their main website Audio GD specifies four different USB interfaces:
 a) USB-32
 b) Amanero combo 384
 c) Xmos U8
 d) Xmos U208 (since Nov 2016)
 Is there any consensus regarding the above in the meaning of "best audio" performance?


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## Pharmaboy

mike nee said:


> Hi, have you heard theirs NFB-1AMP? Or maybe you know of any comparison between SA31SE and NFB-1AMP?
> 
> On their main website Audio GD specifies four different USB interfaces:
> a) USB-32
> ...


 
  
 No, I haven't heard the NFB-1. At one point I was very interested in this balanced amp & its SE version, the C-2. One Head-Fi pal has the C-2 and really likes it. The price of each was right, but I ended up going in other directions. Also, at the time I was interested in these, I couldn't decide on balanced vs SE--had a ZMF Ori on the horizon, knew I'd want to run it balanced.
  
 Then I read this entire thread for the SA-31SE (which is SE but also has a 4-pin XLR "convenience output") and knew I had to hear it.
  
 Re USB interfaces, of course those don't apply to these amps, though they probably do apply to the DAC that's also (confusingly) named "NFB-1." I have the Audio GD NOS 19; as of 8/16 (date of purchase) it had the latest/greated Amanero implementation. I did install the driver (w/the usual great difficulty/annoyance/confusion for Audio GD drivers) and listened to it via USB input. However, I found the coax input (1.3 Oyaide DR-510 coax cable coming from Musical Fidelity V192 Link) sounded better than direct USB--as it does on every DAC I've had.
  
 Re all the Audio GD USB implentations, you can read about them in extreme detail in the Audio GD DAC-19 thread (some, but not all implementations are available on other DACs & all-in-one units). Honestly, I find it hard to keep track of all that detail...


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## Mike Nee

pharmaboy said:


> Re USB interfaces, of course those don't apply to these amps, though they probably do apply to the DAC that's also (confusingly) named "NFB-1." I have the Audio GD NOS 19; as of 8/16 (date of purchase) it had the latest/greated Amanero implementation. I did install the driver (w/the usual great difficulty/annoyance/confusion for Audio GD drivers) and listened to it via USB input. However, I found the coax input (1.3 Oyaide DR-510 coax cable coming from Musical Fidelity V192 Link) sounded better than direct USB--as it does on every DAC I've had.




I asked about the USB interface, as on Polish distributor's website this particular model is listed amongst integrated dac/amp, based on Burr-Brown 1704 chip. Therefore I assumed it would have one of them USB interfaces.

When you wrote about "convenience XLR" output, this meant that SA31SE is not a balanced amp? 
And lastly, there is sth mentioned about possibility of making the sound warmer. Is this a feature found only on "diamond differential" designs, only on "SE" marked models or just sth else? 
I'm interested in both NFB-1AMP and Reference 10.32, but neither of these is described as having the ability to warm the sound.


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## Pharmaboy

mike nee said:


> I asked about the USB interface, as on Polish distributor's website this particular model is listed amongst integrated dac/amp, based on Burr-Brown 1704 chip. Therefore I assumed it would have one of them USB interfaces.
> 
> When you wrote about "convenience XLR" output, this meant that SA31SE is not a balanced amp?
> And lastly, there is sth mentioned about possibility of making the sound warmer. Is this a feature found only on "diamond differential" designs, only on "SE" marked models or just sth else?
> I'm interested in both NFB-1AMP and Reference 10.32, but neither of these is described as having the ability to warm the sound.


 
  
 Audio GD has confusing model names. As I mentioned, there are 2 "NFB1" products, but they're very different:

*NFB1-DAC:* Being a DAC, not an amp, this unit would have a USB implementation. Per the Audio GD website, it's "*32bit / 384K Asynchronous Transfer  XMOS U208 Chip*" w/a "Custom Upgrade" available to "*Upgrade to the Amanero combo384 USB module:*" Here's the product page: http://www.audio-gd.com/Pro/dac/NFB12017/NFB12017EN.htm
*NFB1-AMP:* This is an amp only, no DAC involved. So no USB implementation. Here's the product page: http://www.audio-gd.com/Pro/Headphoneamp/NFB1AMP/NFB1AMPEN.htm
  
 The SA-31SE is single-ended all the way. The XLR output (I believe) simply transmits the single-ended output via 4-pin XLR for "user convenience." And I will be using the XLR when my balanced cable comes in for the Ori. But unlike true balanced amps, I won't experience 6 dB more power or a somewhat better/different sound via the XLR vs SE outputs on this amp.
  
 Re the "warming" controls, again, Audio GD is very confusing in this regard. Some (not all) of their all-in-one units have this feature, which seems to apply only to the DAC section. For example, I had an NFB-15.32 all-in-one that had multiple filter settings on the front panel, some said to produce "warmer" sound than others. And my NOS 19 DAC definitely has several jumper settings (you have to take off the top cover do add or remove jumpers to the circuit board) said to make sound warmer.
  
 My SA-31SE (which is amp only--no DAC) also has 2 jumper setting, "Warm" and "Warmer." But the NFB1-AMP apparently does not have this capability.
  
 With Audio GD (many models/much confusion), you have to carefully review the product page for each model to check what exact USB implementations are available (if it is a stand-alone DAC, or an all-in-one), and jumper or front-panel settings to warm the sound (some DACs; some amps).
  
 Like I said--very confusing...


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## Mike Nee

pharmaboy said:


> Audio GD has confusing model names. As I mentioned, there are 2 "NFB1" products, but they're very different:
> 
> *NFB1-DAC:* Being a DAC, not an amp, this unit would have a USB implementation. Per the Audio GD website, it's "*32bit / 384K Asynchronous Transfer  XMOS U208 Chip*" w/a "Custom Upgrade" available to "*Upgrade to the Amanero combo384 USB module:*" Here's the product page: http://www.audio-gd.com/Pro/dac/NFB12017/NFB12017EN.htm
> *NFB1-AMP:* This is an amp only, no DAC involved. So no USB implementation. Here's the product page: http://www.audio-gd.com/Pro/Headphoneamp/NFB1AMP/NFB1AMPEN.htm


 
 Thx again for reply. I'm aware of two separate NFB-1 models. I was referring to NFB-1AMP and Reference 10.32 mostly as amps, taking silent joy in the fact that 10.32 is a DAC as well (4x1704) and would save me pondering over upgrading my well seasoned Arcam irDAC. Two birds killed with one stone.. I've also learned today that this particular unit of 10.32 I'm interested in has VIA Vinyl Audio VT1731 USB interface and it is not possible to upgrade this to neither XU208 nor Amanero 384. As I don't have funds to purchase separate USB interface I must rely on built-in interface done right. Hence I bias towards Denafrip Ares now or the Singularity 19, but I must educate myself more on NOS vs OS DACs.


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## geomaso44

I have one 230V-compatible unit for sale currently if interested: https://head-fi.org/threads/fs-ft-audio-gd-sa-31se-230v.865975/

Its a great-sounding versatile amp that has served me well for a long time but decided to move on to tube amps currently.


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## heybaroo

Pharmaboy said:


> Don't know if anyone is still following this thread, but I just have to weigh in on the Audio GD SA-31SE.
> 
> I bought mine from a Head-Fi bud about 6 weeks ago, around the same time I got a new ZMF Ori. Those are incredible headphones that do everything rather differently & better than I'm used to. They sound spectacularly good through the SA-31SE. But oddly enough, the Ori made it harder to figure out what this amp can do (studying 2 unknown variables is harder than just one).
> 
> ...



Very late reply but haven't been here in quite a while...did you end up trying the Fidelio X2s with the SA-31. I'm thinking about getting some second hand ones... although possibly not necessary as I have some HD6XXs on their way...


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## Pharmaboy

heybaroo said:


> Very late reply but haven't been here in quite a while...did you end up trying the Fidelio X2s with the SA-31. I'm thinking about getting some second hand ones... although possibly not necessary as I have some HD6XXs on their way...



I honestly don't remember trying the X2s with the SA-31, or what the result was. A lot has changed in my system since then--including addition of Violectric V281 & Cavalli Liquid Carbon.

One thing that has not changed is the X2s. They're terrific, fun, enjoyable headphones. I have other headphones that beat them in numerous ways, but it doesn't seem to matter: every time I put on the X2s, I enjoy them & the music. Guess it's the combination of open-back relaxed sound & imaging, plus the strong bass/mid-bass and natural treble. Other headphones do detail; the X2s do music.

I recommend that you get a pair. But you'll discover that the original X2s are being discontinued & may be hard to find. Philips is selling a new/"improved" HD version of the X2s that look exactly the same but are said to feel & sound slightly different. They also are priced higher.

If you can get a pair of original X2s, either new or used, I would recommend that. There are other threads here dedicated the X2s.

BTW, I still use the SA-31SE quite often, but mostly as a preamp (it is a superb preamp). As a headphone amp it is rather subtle and unpredictable: it sounds dramatic & great w/this headphone, but not that. I've concluded that the assets of the SA-31SE as a headphone amp are its extreme power; but also its consistent subtlety, particularly in midrange soundstaging. It's a shape-shifter, and despite all that power, the very opposite of a brute-force SS amp sound.


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## Pharmaboy

heybaroo said:


> Very late reply but haven't been here in quite a while...did you end up trying the Fidelio X2s with the SA-31. I'm thinking about getting some second hand ones... although possibly not necessary as I have some HD6XXs on their way...



In 1st reply missed your comment about getting the HD6XX's. I only heard 1 HD650, and it was modded. I thought the mod must be very successful, because the headphones really impressed me with their even, unhyped rendition of all frequencies & pinpoint focus in soundstaging and sonic detail. Very clear & focused, but not bright at all--interesting combination. Anyway, IMO, despite the surface similarities between the open-back X2s and HD650's, they couldn't be more different. The X2s give an entirely different sonic view: diffuse soundstage, bassy, slightly warm.

I'd want to own both of those headphones.

BTW, after thinking about it, I do remember one experience w/the X2s on the SA-31SE. It was not exactly what you'd expect, because I was experimenting w/new Brainwavz round pleather earpads used in place of the X2's stock velour earpads (rather difficult to switch these pads...check X2s thread for more detail. Anyway, this was during the summer and I was trying the X2's + new earpads on all my amps. When I plugged them into the SA-31SE, I got one of those fortuitous "lock-in" moments, where a given amp and pair of headphones lock-in and provide great sound. I got the best sound w/that headphone + pads on the SA-31SE vs other amps. A fun night.


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## heybaroo

Pharmaboy said:


> In 1st reply missed your comment about getting the HD6XX's. I only heard 1 HD650, and it was modded. I thought the mod must be very successful, because the headphones really impressed me with their even, unhyped rendition of all frequencies & pinpoint focus in soundstaging and sonic detail. Very clear & focused, but not bright at all--interesting combination. Anyway, IMO, despite the surface similarities between the open-back X2s and HD650's, they couldn't be more different. The X2s give an entirely different sonic view: diffuse soundstage, bassy, slightly warm.
> 
> I'd want to own both of those headphones.
> 
> BTW, after thinking about it, I do remember one experience w/the X2s on the SA-31SE. It was not exactly what you'd expect, because I was experimenting w/new Brainwavz round pleather earpads used in place of the X2's stock velour earpads (rather difficult to switch these pads...check X2s thread for more detail. Anyway, this was during the summer and I was trying the X2's + new earpads on all my amps. When I plugged them into the SA-31SE, I got one of those fortuitous "lock-in" moments, where a given amp and pair of headphones lock-in and provide great sound. I got the best sound w/that headphone + pads on the SA-31SE vs other amps. A fun night.



Thank you so much for your detailed and insightful comments. Probably the tipping point I've needed to get a pair. I've wanted to try a pair since they came out as the majority of reviews and comments align with my sound preferences as do most ZMF headphones. Looking at your list of gear, you seem to currently own quite a few things sound signature wise, I would like to try as well especially the V281, Liquid Carbon, NOS 19, Ori, and E-mu...

Like yourself, I've come into desktop audio from a two channel setup including Cayin tube amplifier, hybrid tube cd player, and Dynaudio standmounts. Small children combined with a large mortgage have necessitated large audio changes...

I've been particularly impressed with the value proposition offered by a digital setup particularly with pro audio gear. 

I'm hoping to come across that synergy that you had that night with the X2s, pads and SA-31 SE. Always makes for a great night when it's found...

Anyway, thanks again for your insights. As luck would have it, I've just received a notification that the X2s I was looking at have just sold...oh well, I'll keep looking. Hopefully, one day soon, (as the mortgage decreases) we can share thoughts on some ZMF headphones and amp combinations...


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