Soulution 701 monoblocks and 711 stereo amplifier

ack

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I guess it was easier to find it than I thought http://www.theabsolutesound.com/art...block-amplifier-and-720-preamplifier-tas-199/

TAS:The Soulution gear sets new standards of low noise and high resolution, making it the most transparent-to-sources and the most realistic solid-state gear I’ve yet heard. Can you tell us a bit about the technology that has led to these breakthroughs? Particularly bandwidth and distortion?



Cyrill Hammer: For a “solid-state” amplifier design the speed (e.g., bandwidth) of amplification is one of the most important criteria. This speed or bandwidth has nothing to do with the MHz-range frequencies that can be reproduced by such an amplifier; the bandwidth is required to make the “feedback loops” of solid-state designs work properly. “Feedback loops” compare the amplified music signal at the output with the input signal. Due to the fact that the music signal is constantly changing, the time delay (propagation delay) of the amplifier must be zero; otherwise, applying feedback will add timing errors to the music signal. In other words, if the propagation delay is not zero or close to zero the “feedback loop” will be comparing apples at the output to oranges at the input.

Big solid-state amplifiers can have propagation delays of 1–5 microseconds. Now, the period of a 20kHz sine wave is 50 microseconds. Under these conditions such timing errors are significant—and they get even worse for higher frequencies. The Soulution amplifiers work with an overall propagation delay of 5–10 nanoseconds. This is up to 1000 times faster than other amplifiers. The voltage amplification stage—where we apply the most negative feedback—runs at 80MHz bandwidth and has a propagation delay of 1–2 nanoseconds. Since the timing errors of the Soulution amplifiers are negligible, this gives us the opportunity to apply as much negative “feedback” as we need wherever it is required in the amplifier without reducing sonic performance. This is how we can lower distortion to never-before-seen levels.
 

hifikontoen

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dallasjustice

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No offense, but read this if you are uncertain whether the Soulution-engineers know their stuff:
http://www.stereophile.com/content/soulution-710-power-amplifier-measurements

When it deserves its extreme price is another thing (but unlike som other out-of-the-world priced high-end products, it is well-engineered)

Friendly regards from me.
My comments are based on actual first hand experience over several months comparing the 710 to other top amps in an otherwise highly resolving system. I never said their FFT measurements didn't look awesome. The 710 represents a technical achievement. An FFT noise floor measurement or IMD measurement doesn't say everything about how an amp sounds. If you are interested, I could give you my impressions comparing the 710 against a pair of Krell 900e in my system. Both cost the same, so it would be a pretty fair comparison.
 
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KeithR

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No offense, but read this if you are uncertain whether the Soulution-engineers know their stuff:
http://www.stereophile.com/content/soulution-710-power-amplifier-measurements

When it deserves its extreme price is another thing (but unlike som other out-of-the-world priced high-end products, it is well-engineered)

Friendly regards from me.

The better question is if they sound good with the negative feedback that is used with them to generate such low distortion numbers.
 

opus111

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No offense, but read this if you are uncertain whether the Soulution-engineers know their stuff:
http://www.stereophile.com/content/soulution-710-power-amplifier-measurements

We already have a quote from Cyril Hammer on this thread which suggests to me very strongly that he doesn't. To wit he said 'Big SS amps have propagation delays of 1-5uS'. To me this sounds ludicrous - a 1uS propagation delay represents about 500ft of coaxial cable. A propagation delay does indeed mean a pure delay - I know of no mechanism in a poweramp which could give rise to such a long delay.

Its possible he's confusing the phase response of the amp with a propagation delay, but engineers who know their stuff don't make this kind of mistake.
 

dallasjustice

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I have Krell 900e monoblocks.

What did you end up with? Sorry, I haven't been following everyone's system changes. There was a very interesting sidebar in the TAS review a few years ago, explaining their unique negative-feedback approach in the 700 series. I certainly thought it was ground-breaking. I'll see if I can dig it up...
 

asiufy

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I don't think Cyril is an engineer, or at least THE engineer at Soulution. Apparently, the actual lead engineer left the company, and there's a new one in. Thus, SMPS.
And, IMO, the Soulution amps sound bland and gimicky. All that negative feedback is there, you can almost hear it :)
I found them to sound pretty much like a Halcro of years past.

alexandre
 

wizard

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701/711 PSU - 4 big black caps from Mundorf.
 

opus111

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Very interesting internal pics - thanks wizard!

Looks like a complete mess design-wise. 4 off-the-shelf SMPSU blocks and six off-the-shelf toroids and no signs of RF filtering except two low inductance toroidal CM chokes. The huge caps under the board will have SRFs too low to filter out the switching noise of the PSUs. Its no surprise to me that many don't like the sound...
 

asiufy

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Any reason why you believe these are off-the-shelf parts?


alexandre
 

opus111

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Sure - because when custom designed we'd reduce the complexity and hence number of parts to better optimize the design. So for example rather than six off-the-shelf toroids I'd reduce that to a single one with multiple secondary windings. Same for using 4 SMPSU 'bricks' rather than a single one.
 

opus111

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Big capacitance also brings with it big inductance - those have 20nH series inductance meaning they resonate below 4kHz. SMPSUs normally switch around 10X that frequency meaning those caps are effectively useless for filtering out the noise. If you look inside the box of an SMPSU you'll notice they use a bank of small caps on the output, not a single big one. That's for a very good reason - minimizing series inductance.
 

defride

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Wow, this thread has degenerated into a bit of a trashing.

Has anyone examined how Soulution may have overcome the implementation problems highlighted in the thread? This company has implemented some pretty innovative solutions in past products.

I've heard systems running a 720/710 combination sound decidedly mid-fi, I've also heard those same components in the same room set up more carefully sound staggeringly good. To me, speakers and amplifiers that reflect the character of the rest of the setup are worthy of respect and in this respect the Soulution 700 components play at the highest level IME.

I'll keep an open mind regarding the new range until I've heard them in a setting I'm familiar with.
 

MylesBAstor

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Wow, this thread has degenerated into a bit of a trashing.

Has anyone examined how Soulution may have overcome the implementation problems highlighted in the thread? This company has implemented some pretty innovative solutions in past products.

I've heard systems running a 720/710 combination sound decidedly mid-fi, I've also heard those same components in the same room set up more carefully sound staggeringly good. To me, speakers and amplifiers that reflect the character of the rest of the setup are worthy of respect and in this respect the Soulution 700 components play at the highest level IME.

I'll keep an open mind regarding the new range until I've heard them in a setting I'm familiar with.

+1

I know a picture is worth a 1000 words but this is beyond ridiculous. Opus appears to be the only person in the world who knows how to design audio equipment. Everyone else is an idiot.

Rather than passing judgement, it might be better to ask questions.
 

microstrip

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Wow, this thread has degenerated into a bit of a trashing.

Has anyone examined how Soulution may have overcome the implementation problems highlighted in the thread? This company has implemented some pretty innovative solutions in past products.

I've heard systems running a 720/710 combination sound decidedly mid-fi, I've also heard those same components in the same room set up more carefully sound staggeringly good. To me, speakers and amplifiers that reflect the character of the rest of the setup are worthy of respect and in this respect the Soulution 700 components play at the highest level IME.

I'll keep an open mind regarding the new range until I've heard them in a setting I'm familiar with.

+1,

Unfortunately it is usual about expensive equipment - people trash it because in their dreams it sounded bad or because some people did not like the sound of the SYSTEM at a show ...
But IMHO even worst is making suppositions on sound quality based on some basic elementary electrical properties of the large size components and looking at the photos.
 

microstrip

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So, many don't like the sound?

...Quite expensive for inferior sound quality!

I hope you forgot to add many smiles to your comment ...
 

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