Amplifier recommendations for 3A Signatures

[ctsooner]

Does Ralph use Vandersteen speakers?  If not how would he know how feedback affects the sound?  Just curious as it would be like Richard talking about how a Constellation set of monos sound with his speakers if he’s not familiar how they sound together. 

[GdnrBob]

26 minutes ago, ctsooner said:

Does Ralph use Vandersteen speakers?  If not how would he know how feedback affects the sound?  Just curious as it would be like Richard talking about how a Constellation set of monos sound with his speakers if he’s not familiar how they sound together. 

From our conversation yesterday, I gather that he doesn't.

Ralph's take on feedback is that it introduces odd harmonics, which the ear translates to harshness.  (See Section 1-http://atma-sphere.com/en/resources-paradigms-in-amplifier-design.html)

He mentioned that in his Class D, you can introduce much more Gain Balance Feedback than traditional amps, yet not incur the sound degradation associated with it.

Like I said, I ordered a pair. So, in a couple of months, I/we will get to find out if they work with Vandy speakers. Yes, I should be saving money for Mr. V's amps, but this Class D thing is an itch I want to scratch. It only got worse when Ralph built his amps.

They say 'Knowledge is Power', so I hope to be gaining some knowledge, albeit at a (monetary) price.

Bob 

[Richard Vandersteen]

1 hour ago, GdnrBob said:

From our conversation yesterday, I gather that he doesn't.

Ralph's take on feedback is that it introduces odd harmonics, which the ear translates to harshness.  (See Section 1-http://atma-sphere.com/en/resources-paradigms-in-amplifier-design.html)

He mentioned that in his Class D, you can introduce much more Gain Balance Feedback than traditional amps, yet not incur the sound degradation associated with it.

Like I said, I ordered a pair. So, in a couple of months, I/we will get to find out if they work with Vandy speakers. Yes, I should be saving money for Mr. V's amps, but this Class D thing is an itch I want to scratch. It only got worse when Ralph built his amps.

They say 'Knowledge is Power', so I hope to be gaining some knowledge, albeit at a (monetary) price.

Bob 

The amps should work better than those of us who use analog as I understand you are 100% digital for source anyway, so you have taken the hit already.  RV

 

 

[GdnrBob]

Okay, Mr. V.,

Just because I don't want to deal with warped, slightly uncentered vinyl records, doesn't mean I am loosing that much in sound quality.

(BTW- I am just kidding you).😉

B

[Holmz]

5 hours ago, GdnrBob said:

...

Like I said, I ordered a pair. So, in a couple of months, I/we will get to find out if they work with Vandy speakers. Yes, I should be saving money for Mr. V's amps, but this Class D thing is an itch I want to scratch. It only got worse when Ralph built his amps.

They say 'Knowledge is Power', so I hope to be gaining some knowledge, albeit at a (monetary) price.

 

 

Since there are no dealers in the US that carry both Atmasphere, and Vandersteen, I eagerly await your evaluation Bob.

[Richard Vandersteen]

3 hours ago, GdnrBob said:

Okay, Mr. V.,

Just because I don't want to deal with warped, slightly uncentered vinyl records, doesn't mean I am loosing that much in sound quality.

(BTW- I am just kidding you).😉

B

It is very important you never do a direct comparison, ticks, pops, warps and all!  I am not kidding.  I do appreciate you selecting our speakers and your support.  RV

[GdnrBob]

19 hours ago, Richard Vandersteen said:

I do appreciate you selecting our speakers and your support.  RV

Thanks Mr. V. 

Your speakers were the benchmarks I remembered 30 for or so years after hearing them at a store near 64th st and Lexington in Manhattan (I forgot the name, but they were shortlived).

Finding the Model 2's (which I demoed in the early '80's) were still being made after was quite a pleasant surprise.

Hearing the improvement in sound reproduction of the Treo's vs. the 3a sigs only confirmed my opinion that you make a great product.

 

bob

[atmasphere]

On 9/13/2022 at 4:59 PM, Richard Vandersteen said:

The amps should work better than those of us who use analog as I understand you are 100% digital for source anyway, so you have taken the hit already.  RV

Just a FWIW Dept.: class D amplifiers are an entirely analog process, although they are primary a switching technology and there are examples that have DACs built in. The 'D' isn't for 'digital'; class D was proposed in the 1950s and A, B and C were already taken.

[Holmz]

4 hours ago, atmasphere said:

… D was proposed in the 1950s and A, B and C were already taken.

Sounds lke my professors and teachers explaining how she/he arrived at my grade. 🥲

[ctsooner]

Ralph, I may be wrong, but It’s more of the feedback that many may be asking about and why you may lose the time and phase correctness that most Vandy owners treasure. Others know more about this than I, but when auditioning many amps, the ones with too much feedback just never have sounded as good as the ‘zero feedback’ designs. 

[ctsooner]

Btw, I have always enjoyed your products when I’ve heard them in systems. 

[Richard Vandersteen]

On 9/15/2022 at 10:36 AM, atmasphere said:

Just a FWIW Dept.: class D amplifiers are an entirely analog process, although they are primary a switching technology and there are examples that have DACs built in. The 'D' isn't for 'digital'; class D was proposed in the 1950s and A, B and C were already taken.

While this is true there are some similarities.  In a linear amp class A/B you have a continuous signal with power gain.  In class D the signal is sampled at a high speed then fed to the output stage as a high-speed square wave which is modulated towards a positive signal or negative signal by changing the on time and off time.  The signal is then filtered to remove the high frequency square wave carrier and what is left is the reconstructed music waveform with some inherent errors, timing especially. Very efficient, cost effective, great sounding but lacking the emotional connection of many linear feedback free amplifiers on analog sources, YMMV.  RV

[RWP]

grdnrbob, was the store borgers?  

[Stringreen]

On 9/9/2022 at 2:44 AM, ctsooner said:

Didn't Richard say that you lose the time and phase correctness when using Class D as it's digital?  For most Vandy users, I'd think they would want to stick with a zero feedback design and stay away from Class D amps.  I've heard the 3's in an all Rotel system and they sounded great.  I heard the last gen 2's with Sim Moon and they sang.  The Belles gear is also outstanding and for the price, it's hard to beat.  

This is why it may be worth a road trip that he sets up ahead of time to make sure the dealer has at least three brands in his price range to audition.  

for me....the most important advantage of Richard's designs are the time/phase abilities ....that's what puts the air between the instruments and the heart beat faster.  I'm using Ayre equipment.......try to find a "deal" on used stuff 

[Holmz]

How are these things off in timing? 
Does one see the phase start rotating further and further away from zero as the frequency goes up?

I would think that there has to be some way to observe, or quantify, this timing distortion.

[GdnrBob]

21 hours ago, RWP said:

grdnrbob, was the store borgers?  

I have no idea what 'borgers' means.

12 hours ago, Holmz said:

How are these things off in timing? 

Yes, I was wondering the same thing.

From my conversation with Ralph, it seems conventional amps (A, A/B), do not allow application of feedback as it will increase harmonic distortion to a point where it is noticeable. Class D, on the other hand seems to allow a much heavier application without detrimental effects. If this results in Time/Phase distortion, I didn't seem to get a clear answer.

Bob

[RWP]

Borgers was the name of a family-owned stereo store in the location (or near to it) you mentioned.  

[GdnrBob]

48 minutes ago, RWP said:

Borgers was the name of a family-owned stereo store in the location (or near to it) you mentioned.  

Ohh, now I understand.

No, it was not family owned, but maybe it was bought out by the guy I was dealing with. It was a nice spot in a nice row of buildings. I think there were original cast iron railing on the steps up from the pavement.

Bob

[ctsooner]

On 9/18/2022 at 3:26 PM, Richard Vandersteen said:

While this is true there are some similarities.  In a linear amp class A/B you have a continuous signal with power gain.  In class D the signal is sampled at a high speed then fed to the output stage as a high-speed square wave which is modulated towards a positive signal or negative signal by changing the on time and off time.  The signal is then filtered to remove the high frequency square wave carrier and what is left is the reconstructed music waveform with some inherent errors, timing especially. Very efficient, cost effective, great sounding but lacking the emotional connection of many linear feedback free amplifiers on analog sources, YMMV.  RV

 

5 hours ago, GdnrBob said:

I have no idea what 'borgers' means.

Yes, I was wondering the same thing.

From my conversation with Ralph, it seems conventional amps (A, A/B), do not allow application of feedback as it will increase harmonic distortion to a point where it is noticeable. Class D, on the other hand seems to allow a much heavier application without detrimental effects. If this results in Time/Phase distortion, I didn't seem to get a clear answer.

Bob

Bob, is this what you are looking for?  Not sure if this is your answer or not.

[Holmz]

1 hour ago, ctsooner said:

 

Bob, is this what you are looking for?  Not sure if this is your answer or not.

I am not Bob, and I get the gist of how Class-D works... but what would I look for in measurements that shows the small inherent timing errors?
Then I would be able to tell if the Class-D have arrived.

I have heard one Class-D that sounded very good, and one that was acceptable/good.

[GdnrBob]

18 hours ago, ctsooner said:

Bob, is this what you are looking for?  Not sure if this is your answer or not.

Kinda sorta. As I said, Ralph never gave me an answer as to whether the feedback introduced time/phase distortion. I was hoping he would elaborate in his responses here.

FWIW, he did say his Class D amps better his tube amps, in his opinion.- Which I think is saying something.

Bob

[ctsooner]

If there is a timing issue and you are analog, you'll lose what Vandy's do that most others can't.  I think this thread is all about building a system that has synergy.  I've always been about synergy when putting my systems together.  

It's not about knocking others products and I hope it doesn't come off that way.  I was reading a thread on AG about this amp and Ralph tries to help educated folks on Class D.  It's fighting up stream but you have ot have folks willing to do that in order to move forward.  I know a few of you have purchased it and I look forward to your thoughts. 

[Holmz]

10 minutes ago, ctsooner said:

If there is a timing issue and you are analog, you'll lose what Vandy's do that most others can't.  I think this thread is all about building a system that has synergy.  I've always been about synergy when putting my systems together.  

I am trying to figure if the premise is correct with the timing issue, and then how to tell whether an amp has it.
I like analogue, but the digital sounds pretty good. And with the MoFi debacle I am not sure with a digitised chain before the pressing, how the timing would be affected or not.

 

10 minutes ago, ctsooner said:

It's not about knocking others products and I hope it doesn't come off that way.  I was reading a thread on AG about this amp and Ralph tries to help educated folks on Class D.  It's fighting up stream but you have ot have folks willing to do that in order to move forward.  I know a few of you have purchased it and I look forward to your thoughts. 

That thread is a royal S-show. There seems to be level of behavior there that is designed to encourage childishness, or at least tolerates it.

[nrenter]

At risk of adding little to no value to this thread…

 

Any amplifier that uses feedback to stabilize the the circuit is introducing “timing” issues into the signal, as the (negative) feedback is attenuated and added back to the source signal (180 degrees out of phase).
 

Local loop negative feedback isn’t as egregious as global loop negative feedback (as, global feedback is reintroduced into the local loop feedback circuits, compounding). To some, it’s audible. To others, the trade offs are worth the costs.
 

I used to have a pair of AES Sixpacs that could switch between 0 dB and 10 dB of negative feedback.  The impact, for those particular amps, was profound. I preferred one of the options more than the other. However, I could understand someone preferring the other. 
 

Richard Hardesty has some good commentary (and interviews) on the subject out at…

http://www.vandersteen.com/audio-perfectionist-journal

 

[GdnrBob]

1 hour ago, Holmz said:

That thread is a royal S-show. There seems to be level of behavior there that is designed to encourage childishness, or at least tolerates it.

I concur. It is one of the reasons I find this group to be much more enjoyable.- Add to that, the idiotic  click on the lions security measures.

@nrenter, 

Thanks for reminding me to re-read those issues. Though I didn't know about it when it came out, much of what was written so long ago (well, 20+ years ago), still applies.

Bob