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Audio GD SA-31 head amp/ preamp . A powerfull Head Amp with Diamond Difference design . - Page 2

post #16 of 391
so, did anyone ordered and already recieved their amp? curious about the sound of the new ones.

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post #17 of 391

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. 

post #18 of 391

Why not the Master-8?

post #19 of 391

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.

post #20 of 391
Any more impressions on this amp?
post #21 of 391

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 "WTF 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 biggrin.gif 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. wink.gif
 


Edited by FauDrei - 9/18/12 at 8:56am
post #22 of 391
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.
post #23 of 391
Quote:
Originally Posted by FauDrei View Post

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 "WTF 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 biggrin.gif 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. wink.gif
 

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.

post #24 of 391

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.


Edited by JWahl - 9/21/12 at 4:53am
post #25 of 391
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
post #26 of 391
I'm not sure what the 1w requirement is honestly. If you put 1w into them your ear drums will rupture.
post #27 of 391

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 sh*t out of HE-500. But HE-500 can take it. Without distortion. Excellent, excellent pairing.

post #28 of 391
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.
Edited by Mad Lust Envy - 9/23/12 at 3:55am
post #29 of 391

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.

 

 

Quote:
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.

post #30 of 391
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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