Author Topic: I think my System is finally finished  (Read 5551 times)

Offline steve

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Re: I think my System is finally finished
« Reply #45 on: August 27, 2020, 10:32:41 PM »
That out of band undamped resonance has been the flaw with all of the drivers I've seen with very stiff cones.
According to distortion plots  I've seen of both the raw drivers and complete speaker systems the out band resonance point has a very large amount of 3rd order harmonic distortion associated with it. Even when this resonant peak is suppressed X dB with a 24db/oct. network the 3rd order distortion can be heard by many people and is very off putting.
 Sidebar, the dynamic life of the music takes a hit every time another component is added to the X over network in my opinion , which why I am proponent 1st order networks even though speakers designed this way usually come with off axis frequency response errors. The music sounds more alive to me and the off axis response errors can be ameliorated by appropriate room treatment.
Obviously YMMV.
Scotty

I agree Scotty. Resonances in, above, below the audio band cause all sorts of problems. Thanks for posting this
valuable information.

On a side note, I try very hard to keep my strings clean, keep the shovel in the shed. However, as a fool, at midnight,
I checked a link in this string, and had to get the shovel out and the hip boots on. It got pretty deep.

cheers
steve
« Last Edit: August 28, 2020, 02:38:26 PM by steve »
Steve Sammet (retired, owner, SAS Audio Labs)
"V" Very Low Capacitance ICs, 40pf 1 meter
SAS Audio Labs Test Phono Stage
SAS Audio 11A Tube Reference Preamplifier
SAS Audio Labs 25 W Triode Reference Monoblocks
2 way test Spkrs, 28 - 20khz  -3db (28hz)

Online doug s.

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Re: I think my System is finally finished
« Reply #46 on: August 28, 2020, 10:32:36 AM »
hi steve,

i suspect this is the midwoofer that coincident uses in its top speakers:
https://www.madisoundspeakerstore.com/approx-6-midrange/accuton-c173-6-090-6.5-ceramic-cone-midrange/
its fs is 57hz, and it's crossed over to subwoofers at 100hz in the coincidents; it's not the fs of 581hz like the one you linked.  and no large frequency peak at higher frequencies like the one you linked.

and the point scotty made re: distortion, the midrange driver i linked has ~1.5% 2nd order distortion between 5-6khz, (no 3rd order to speak of); accuton says this about it:
"Anti-resonant cutout fills in the ceramic dome provide for damping of the 6 kHz dome resonance."

and this is the tweeter:
https://www.madisoundspeakerstore.com/hard-dome-tweeter/accuton-c30-6-024-1.2-ceramic-dome-tweeter-neodymium-magnet/

and, its 1st order crossover implementation is minimal - 1 cap and 1 inductor on the mid/tweet. and 1 inductor on the mid/subwoofers.

coincident may have some custom work done for its drivers by accuton, but as-is, the driver's frequency plots seem to indicate they could blend well, with appropriate cabinetry and crossover design.  and that audio nerd arthur salvatore, who has interesting things to say about all things audio, [http://www.high-endaudio.com/], thinks the top coincident model is the best speaker period, regardless of price.  personally, i'd love to hear these speakers.  there's a pair of the next model down - same drivers, but one box - f/s used at a great price, and i'm sorely tempted.  too bad i'm on furlough at present.  or maybe, it's a good thing!  ;)

doug s.

Don't get me wrong Doug, I really appreciate the suggestions and thoughtfulness. I think I have heard of Accuton, but never
checked them out.

It is just that I am extremely picky when it comes to drivers, and I almost always go with the flattest response. Yes, there are other parameters such as cone material, the ts and Xmax values etc that I also take into account.

Past this point is more for newbies, not at Doug.

For instance, Qts is all important for me when it comes to woofers for my test speaker. An Fs of 20hz with a Qts of .2 is not what I am looking for when I want response to 20hz. I want accurate and tight response even with a tube amp.

Interestingly, two amplifiers can have a damping factor of 10, yet one will "sound" tight bass while the other will have flabby bass.

I went with the old tried and tested big box because it just sounds better than all these new concept types using
the above parameters (Fs 20 and Qts of .2). One of the comments I receive is how in the world did I get such taut and
natural sounding bass (both electric and double bass). Proper speaker design and proper amplifier design.
I realize that many folks do not like large 4.5 cubic foot cabinets. But I find it yields the best bass response. (Even with a 12"
woofer, the Xmas, cone movement, limits the spl of deep bass.)

I don't know which midrange or tweeter is used in a particular design.
But here is the response of a 2" Accuton Cell C51-6-286 2" Ceramic Dome Midrangemidrange driver.

https://www.madisoundspeakerstore.com/approx-2-midrange/accuton-cell-c51-6-286-2-ceramic-dome-midrange/

Below is the FR plot. Using a 1st order, 6db/octave crossover at 4khz is begging for problems. There is
going to be a problem due to the rise above 10khz. My system would easily expose the problem.
A special low pass filter is needed above 10khz or so. But that is more parts which will also influence the purity.
One could also use a 4th order, but again too many parts for me.

Anyway, that is my rant for now.

Cheers and thanks for thinking of me Doug. I do appreciate your thoughtfulness.

steve

Offline steve

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Re: I think my System is finally finished
« Reply #47 on: August 28, 2020, 02:36:07 PM »
hi steve,

i suspect this is the midwoofer that coincident uses in its top speakers:
https://www.madisoundspeakerstore.com/approx-6-midrange/accuton-c173-6-090-6.5-ceramic-cone-midrange/
its fs is 57hz, and it's crossed over to subwoofers at 100hz in the coincidents; it's not the fs of 581hz like the one you linked.  and no large frequency peak at higher frequencies like the one you linked.

and the point scotty made re: distortion, the midrange driver i linked has ~1.5% 2nd order distortion between 5-6khz, (no 3rd order to speak of); accuton says this about it:
"Anti-resonant cutout fills in the ceramic dome provide for damping of the 6 kHz dome resonance."

and this is the tweeter:
https://www.madisoundspeakerstore.com/hard-dome-tweeter/accuton-c30-6-024-1.2-ceramic-dome-tweeter-neodymium-magnet/

and, its 1st order crossover implementation is minimal - 1 cap and 1 inductor on the mid/tweet. and 1 inductor on the mid/subwoofers.

coincident may have some custom work done for its drivers by accuton, but as-is, the driver's frequency plots seem to indicate they could blend well, with appropriate cabinetry and crossover design.  and that audio nerd arthur salvatore, who has interesting things to say about all things audio, [http://www.high-endaudio.com/], thinks the top coincident model is the best speaker period, regardless of price.  personally, i'd love to hear these speakers.  there's a pair of the next model down - same drivers, but one box - f/s used at a great price, and i'm sorely tempted.  too bad i'm on furlough at present.  or maybe, it's a good thing!  ;)

doug s.

Don't get me wrong Doug, I really appreciate the suggestions and thoughtfulness. I think I have heard of Accuton, but never
checked them out.

It is just that I am extremely picky when it comes to drivers, and I almost always go with the flattest response. Yes, there are other parameters such as cone material, the ts and Xmax values etc that I also take into account.

Past this point is more for newbies, not at Doug.

For instance, Qts is all important for me when it comes to woofers for my test speaker. An Fs of 20hz with a Qts of .2 is not what I am looking for when I want response to 20hz. I want accurate and tight response even with a tube amp.

Interestingly, two amplifiers can have a damping factor of 10, yet one will "sound" tight bass while the other will have flabby bass.

I went with the old tried and tested big box because it just sounds better than all these new concept types using
the above parameters (Fs 20 and Qts of .2). One of the comments I receive is how in the world did I get such taut and
natural sounding bass (both electric and double bass). Proper speaker design and proper amplifier design.
I realize that many folks do not like large 4.5 cubic foot cabinets. But I find it yields the best bass response. (Even with a 12"
woofer, the Xmas, cone movement, limits the spl of deep bass.)

I don't know which midrange or tweeter is used in a particular design.
But here is the response of a 2" Accuton Cell C51-6-286 2" Ceramic Dome Midrangemidrange driver.

https://www.madisoundspeakerstore.com/approx-2-midrange/accuton-cell-c51-6-286-2-ceramic-dome-midrange/

Below is the FR plot. Using a 1st order, 6db/octave crossover at 4khz is begging for problems. There is
going to be a problem due to the rise above 10khz. My system would easily expose the problem.
A special low pass filter is needed above 10khz or so. But that is more parts which will also influence the purity.
One could also use a 4th order, but again too many parts for me.

Anyway, that is my rant for now.

Cheers and thanks for thinking of me Doug. I do appreciate your thoughtfulness.

steve

Hi Doug,

Yes, he picked some of the better drivers which is good. There are still some questions I would ask myself though.

The tweeter looks pretty good, although I would like to check out the off axis response. Does it beam? I take it he minimized that
effect. If I had a choice, and gobs of money etc I would go for the Heils air motion transformers, maybe even the ionized helium, requiring tanks. Nah, the tanks are too much bother.
But so far so good.

The midrange is another matter between 2-4khz, within the most sensitive portion of the ear. I still don't like the 5khz and above
either as there is not a gentle, linear downward slope from 1.8khz to 8khz. That 5db "roughness in response" is going to show an unevenness when combined with the tweeters overlaping response. The worst part is the dip covers a whole octave, well above
the 1/3 octave width Rane claims is the minimum width necessary for being perceivable. Less than 1/3 octave is generally not perceivable.

Forgot to mention DB spikes and dips are directly added. For instance, if we have a spike of 5db, then the overlap will show the
5db spike. If we have a dip of 5db, then the overlap will dip 5db.

Not to worry Doug, I have had the same problem whenever I look at any 3 way design. Overlapping always occurs, worse with lower order crossover designs. That is why I went with a two way design, just one overlap to deal with, and at a much lower frequency.

Cheers

steve
« Last Edit: August 29, 2020, 05:59:06 PM by steve »
Steve Sammet (retired, owner, SAS Audio Labs)
"V" Very Low Capacitance ICs, 40pf 1 meter
SAS Audio Labs Test Phono Stage
SAS Audio 11A Tube Reference Preamplifier
SAS Audio Labs 25 W Triode Reference Monoblocks
2 way test Spkrs, 28 - 20khz  -3db (28hz)

Offline steve

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Re: I think my System is finally finished
« Reply #48 on: September 12, 2020, 07:34:40 PM »
Well, I made two more adjustments to the system. I went back to ten 18 gauge wires on both legs of my speaker cables.
This necessitated the lessening of the inductance by ~1 inch of one turn. These adjustments affect mainly the
upper bass/lower midrange output, which affects the perception across the entire audio band.

Going to check over many selections to see if any other touch ups might be necessary.

This is one minute adjustment, yet still made a positive sonic difference in the "lab".

cheers

steve
« Last Edit: September 12, 2020, 07:40:18 PM by steve »
Steve Sammet (retired, owner, SAS Audio Labs)
"V" Very Low Capacitance ICs, 40pf 1 meter
SAS Audio Labs Test Phono Stage
SAS Audio 11A Tube Reference Preamplifier
SAS Audio Labs 25 W Triode Reference Monoblocks
2 way test Spkrs, 28 - 20khz  -3db (28hz)

Online doug s.

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Re: I think my System is finally finished
« Reply #49 on: September 12, 2020, 07:59:39 PM »
 re: the accutons; well, while not having heard mr blume's top creations, all i can say is i've never heard anyone who has, say anything less than they're one of the best speakers they've ever heard.

interesting you should mention the heil amt's.  their largest driver - 6" tall -  is rated 800hz to 20khz and 96db efficient.  i've always wondered how a stack (8, 9 or 12 drivers per side) would sound.  retail for 24 of them would be $4800 - not chump change, but within the realm of affordability.  ( and if you wanted to buy 24, i suspect the mfr might provide a bit of a price break.)  i wonder how low you could cross them, if running that many.  12 drivers would be something like ~106-107db efficient; i bet you could cross them over quite a bit lower and be successful, w/eq...

best,

doug s.

Hi Doug,

Yes, he picked some of the better drivers which is good. There are still some questions I would ask myself though.

The tweeter looks pretty good, although I would like to check out the off axis response. Does it beam? I take it he minimized that
effect. If I had a choice, and gobs of money etc I would go for the Heils air motion transformers, maybe even the ionized helium, requiring tanks. Nah, the tanks are too much bother.
But so far so good.

The midrange is another matter between 2-4khz, within the most sensitive portion of the ear. I still don't like the 5khz and above
either as there is not a gentle, linear downward slope from 1.8khz to 8khz. That 5db "roughness in response" is going to show an unevenness when combined with the tweeters overlaping response. The worst part is the dip covers a whole octave, well above
the 1/3 octave width Rane claims is the minimum width necessary for being perceivable. Less than 1/3 octave is generally not perceivable.

Forgot to mention DB spikes and dips are directly added. For instance, if we have a spike of 5db, then the overlap will show the
5db spike. If we have a dip of 5db, then the overlap will dip 5db.

Not to worry Doug, I have had the same problem whenever I look at any 3 way design. Overlapping always occurs, worse with lower order crossover designs. That is why I went with a two way design, just one overlap to deal with, and at a much lower frequency.

Cheers

steve

Offline steve

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Re: I think my System is finally finished
« Reply #50 on: September 13, 2020, 06:17:35 PM »
Could be good, but I am not everyone. I use specs, but even more, sophisticated/proprietary listening tests, that no one else uses. I have also "worked" with some exemplary individuals if I may.

Jneutron and I communicated and posted together some years ago. Jneutron worked at FermiLab, then Cern when they were designing and building it, last I heard J is at Brookhaven National Laboratory. He has "professored" other scientists in the classroom, and been an audiophile/music lover for some two decades now.

Decades ago, when fussing over parts quality, I spent some time conversing with Jenalabs. Michael worked as a sub-contractor on the probes that ventured outside our solar system and Jennifer worked on some "minor" government research projects. They gave me clues which parts were the most accurate, thus saving me valuable time.
By the way, I personally checked out their suggestions for myself.

I ran the lab in college, then my own lab for some decades. I have had students and professors consult me, not often, concerning audio projects etc.

One of the flags I look for when checking out a speaker is what electronic components are used to evaluate said speaker design. Using DHT is yesterdays news, and indicates what their "reference" is. DHTs have inherent limitations/flaws that limit the musical quality. Everything follows laws, whether it is room acoustics, parts quality, the design, or listening tests, in otherwards true Physics, not personal theories.

One of the major barriers that is occurring is that NOS tubes are fleeting, prices are rising; so the challenge is to produce a component that is superior without them. It Can be done.

That is where the 10A and 11A preamplifiers come in. Both preamplifiers are designed around new production tubes.
Both models consistently beat the competition, which use expensive NOS tubes, regardless of price.

That is why you won't find a used 11A for sale. The question is, who will continue the legacy when I am gone?

Sorry for the rant but my string has the goal of informing what is possible in audio vs what others are preaching dooms day with newly manufactured tubes.

I like the Heils, but the crossover point dictates a three way system imo. I would not use one with a xover at 800hz or lower as one would have to address Mr. Doppler, which degrades the sound. I would also not like one higher, say 1.6-2khz either.

I hope you can see my goal more clearly, I have been in uncharted territory for well over 20 years.

cheers

steve



 

re: the accutons; well, while not having heard mr blume's top creations, all i can say is i've never heard anyone who has, say anything less than they're one of the best speakers they've ever heard.

interesting you should mention the heil amt's.  their largest driver - 6" tall -  is rated 800hz to 20khz and 96db efficient.  i've always wondered how a stack (8, 9 or 12 drivers per side) would sound.  retail for 24 of them would be $4800 - not chump change, but within the realm of affordability.  ( and if you wanted to buy 24, i suspect the mfr might provide a bit of a price break.)  i wonder how low you could cross them, if running that many.  12 drivers would be something like ~106-107db efficient; i bet you could cross them over quite a bit lower and be successful, w/eq...

best,

doug s.

Hi Doug,

Yes, he picked some of the better drivers which is good. There are still some questions I would ask myself though.

The tweeter looks pretty good, although I would like to check out the off axis response. Does it beam? I take it he minimized that
effect. If I had a choice, and gobs of money etc I would go for the Heils air motion transformers, maybe even the ionized helium, requiring tanks. Nah, the tanks are too much bother.
But so far so good.

The midrange is another matter between 2-4khz, within the most sensitive portion of the ear. I still don't like the 5khz and above
either as there is not a gentle, linear downward slope from 1.8khz to 8khz. That 5db "roughness in response" is going to show an unevenness when combined with the tweeters overlaping response. The worst part is the dip covers a whole octave, well above
the 1/3 octave width Rane claims is the minimum width necessary for being perceivable. Less than 1/3 octave is generally not perceivable.

Forgot to mention DB spikes and dips are directly added. For instance, if we have a spike of 5db, then the overlap will show the
5db spike. If we have a dip of 5db, then the overlap will dip 5db.

Not to worry Doug, I have had the same problem whenever I look at any 3 way design. Overlapping always occurs, worse with lower order crossover designs. That is why I went with a two way design, just one overlap to deal with, and at a much lower frequency.

Cheers

steve
« Last Edit: December 28, 2020, 02:14:45 PM by steve »
Steve Sammet (retired, owner, SAS Audio Labs)
"V" Very Low Capacitance ICs, 40pf 1 meter
SAS Audio Labs Test Phono Stage
SAS Audio 11A Tube Reference Preamplifier
SAS Audio Labs 25 W Triode Reference Monoblocks
2 way test Spkrs, 28 - 20khz  -3db (28hz)

Offline steve

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Re: I think my System is finally finished
« Reply #51 on: October 22, 2020, 02:13:25 PM »
One more improvement I made, for musical stability purposes, is to exchange a couple of typical single turn potentiometers with 15 turn potentiometers. Too much shaft play in a typical pot for stability, and I need to adjust down to 1/16th turn on the 15 turn pot. Imagine trying that with a single turn pot.

cheers

steve
« Last Edit: December 28, 2020, 02:15:22 PM by steve »
Steve Sammet (retired, owner, SAS Audio Labs)
"V" Very Low Capacitance ICs, 40pf 1 meter
SAS Audio Labs Test Phono Stage
SAS Audio 11A Tube Reference Preamplifier
SAS Audio Labs 25 W Triode Reference Monoblocks
2 way test Spkrs, 28 - 20khz  -3db (28hz)

Offline steve

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Re: I think my System is finally finished
« Reply #52 on: December 17, 2020, 04:58:50 PM »
Some may be wondering why I started this string. For a few reasons.

The first is that as NOS tubes evaporate, there eventually will be none left. It is true that
just about every manufacturer designs around NOS but installs newly manufactured tubes.
So either one settles for second rate sound due to lack of funds for NOS tubes, or at some
future point NOS will become unavailable and all will have to settle for second rate musicality
anyway.

Being futuristic in nature and understanding the developing problem, I decided over 30 years
ago to design specifically around newly manufactured tubes. Those who know me understand
I am a perfectionist and will not stand for second rate musical reproduction. Read the string for
the lengths I will go to obtain the best musical reproduction.

https://www.audionervosa.com/index.php?topic=6954.0

The first area I started with was the line preamplifier. I developed the 11A Line
Preamplifier which is so accurate to the source that one can only match its performance, not
usurp it.

What is amazing is that the 11A, with new tubes, was consistently judged better than
those preamplifiers using NOS tubes, whether indirectly heated or directly heated triodes.
I also did the same with my monoblock triode amplifiers (Ultra-Linear switchable).

Every stage of the preamplifier and monoblock amplifiers utilize a separate power transformer
for each DC plus and for each minus power supply voltage to eliminate musical interactions between
active stages. From the link above, one can see the fanatical attention to every fine detail.

Another example is the 11A uses 6 filter stages and eliminates up front/ac artifacts, isolates the power transformer and recdtifier, as well as an adjustment for differences in amplifier input impedance which affects the bass response.
 
The overall point in my strings is that it is possible to reproduce the very very best musical
quality by using new tubes and other newer parts vs NOS. It was a tough R&D process, but it
can and has been done. Don’t let anyone claim it cannot be done.

I have some reviews if anyone is interested. I will post a couple.

“SAS 10A Tube preamp. (Jon L)

"I must thank Steve once again for giving us the opportunity to audition this wonderful preamp.
My experience closely reflects what's been said in Bound For Sound and Eric, so I will be brief and just emphasize a couple of impressions.

THE strength of this preamp IMO is its sheer ability to communicate music in a way that makes you not even care about how it's doing it.

Let me explain. From pure audiophile point of view and in direct comparison to my EVS Ultimate Nude attenuators, I can nitpick and point out that the upper-midrange is a tad softened compared to dead neutral. The very low bass does not quite have the sheer granite slam of some humongous SS preamps. I'm talking about subtle degrees here, nothing that stands out.

What IS amazing is the fact the treble is just as extended, pure, grainless, and detailed as my EVS. This is an extremely difficult thing for any active preamp to achieve at any price, let alone a tubed preamp. What is even more amazing is that even though EVS does seem to pass more information, I actually enjoyed music more through 10A despite that knowledge. This is a feat that even a Bent silver TVC couldn't achieve against my EVS.

My sense is that there are very limited number of tube preamps out there that actually achieve what a "good tube preamp should do," which is to lend a sense of harmonic completeness, bloom, dimensionality, and plain musicality while NOT sacrificing objectionable amount of detail, extension, neutrality, bass definition/slam. You'd be surprised how many pricey, perhaps even famous, tube preamps do not meet the above definition. SAS 10A IS a "good tube preamp" in all its glory.

There's one thing I must complain about, however, which is the lack of IEC inlet to allow power cord swapping. (I include the jack now.) I am an admitted power cord junkie, and I can think of a few power cords that will minimize the upper midrange softness and add kick to low bass. For example, VH Audio cords will do exactly that for little investment. If I owned the 10A, I would definitely either DIY an IEC inlet, or hardwire a VH cord into the preamp. This combo will be scary good without question.

If I didn't have a system that was purpose-built around passive preamp (EVS), with whopping digital output voltage and 95dB sensitive speakers, I would own the 10A (with VH cord). It's just so musically engaging that this tube-rolling junkie didn't even try to roll any different tubes. FYI, That has not happened for any other tubed equipment that I've used ever..."

NOTE: All my preamplifiers now incorporate an AC IEC Jack, Standard. This allows for rolling power cords. My 10A also has an active stage of gain.

Second quick reviewer, (Earlmarc)

"First up, the SAS 11A preamplifer. Personally, I didn't think it was possible to better the 10A's performance. The 11A took it to another level. The degree of improvement is not in my opinion dramatic but is apparent. All the things I said in previous post about the 10A apply to the 11A, only the 11A increased the real factor to as close to live music as I have ever heard. Everything was more indentifiable and believable. The 11A is truly a reference preamplifier that I believe will stand toe to toe with the best of the best.

Second, the SAS Push/Pull KT88 mono amplifiers. Wow, what can I say. The best sounding amplifiers I've heard, especially when it comes to midrange magic. The palpability of images, the liviliness of voices, the air between notes, etc. I could go on and on about how shockingly real these amps sounded...."

I hope all continue to strive for excellence, as it can be obtained, so don't give up.

Caveat: I have been retired for some 8 years. I may start selling my “V” non shielded interconnects with 6n copper wire and gold plated, all copper RCA plugs again.

Please feel free to reply with questions.

Cheers

steve
« Last Edit: January 12, 2021, 09:58:54 PM by steve »
Steve Sammet (retired, owner, SAS Audio Labs)
"V" Very Low Capacitance ICs, 40pf 1 meter
SAS Audio Labs Test Phono Stage
SAS Audio 11A Tube Reference Preamplifier
SAS Audio Labs 25 W Triode Reference Monoblocks
2 way test Spkrs, 28 - 20khz  -3db (28hz)

Offline Nick B

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Re: I think my System is finally finished
« Reply #53 on: December 17, 2020, 11:01:37 PM »
Some may be wondering why I started this string. For a few reasons.

The first is that as NOS tubes evaporate, there eventually will be none left. It is true that
just about every manufacturer designs around NOS but installs newly manufactured tubes.
So either one settles for second rate sound due to lack of funds for NOS tubes, or at some
future point NOS will become unavailable and all will have to settle for second rate musicality
anyway.

Being futuristic in nature and understanding the developing problem, I decided over 30 years
ago to design specifically around newly manufactured tubes. Those who know me understand
I am a perfectionist and will not stand for second rate musical reproduction. Read the string for
the lengths I will go to obtain the best musical reproduction.

https://www.audionervosa.com/index.php?topic=6954.0

The first area I started with with the line preamplifier. I developed the 11A Line
Preamplifier which is so accurate to the source that one can only match its performance, not
usurp it. What is amazing is that the 11A, with new tubes, was consistently judged better than
those preamplifiers using NOS tubes, whether indirectly heated or directly heated triodes.
Thus I have obtained my perfectionist goal long sought after. I also did the same with my
monoblock triode amplifiers (Ultra-Linear switchable).

Every stage of the preamplifier and monoblock amplifiers utilize a separate power transformer
for each DC plus and minus power supply voltage to eliminate musical interactions between
active stages. From the link above, one can see the fanatical attention to every fine detail.
Another example is the 11A uses 6 filter stages and eliminates up front/ac artifacts.
 
My overall point in my strings is that it is possible to reproduce the very very best musical
quality by using new tubes and other newer parts vs NOS. It was a tough R&D process, but it
can be done. Don’t let anyone claim it cannot be done.

I have some reviews if anyone is interested. I will post a couple.

“SAS 10A Tube preamp. (Jon L)

"I must thank Steve once again for giving us the opportunity to audition this wonderful preamp.
My experience closely reflects what's been said in Bound For Sound and Eric, so I will be brief and just emphasize a couple of impressions.

THE strength of this preamp IMO is its sheer ability to communicate music in a way that makes you not even care about how it's doing it.

Let me explain. From pure audiophile point of view and in direct comparison to my EVS Ultimate Nude attenuators, I can nitpick and point out that the upper-midrange is a tad softened compared to dead neutral. The very low bass does not quite have the sheer granite slam of some humongous SS preamps. I'm talking about subtle degrees here, nothing that stands out.

What IS amazing is the fact the treble is just as extended, pure, grainless, and detailed as my EVS. This is an extremely difficult thing for any active preamp to achieve at any price, let alone a tubed preamp. What is even more amazing is that even though EVS does seem to pass more information, I actually enjoyed music more through 10A despite that knowledge. This is a feat that even a Bent silver TVC couldn't achieve against my EVS.

My sense is that there are very limited number of tube preamps out there that actually achieve what a "good tube preamp should do," which is to lend a sense of harmonic completeness, bloom, dimensionality, and plain musicality while NOT sacrificing objectionable amount of detail, extension, neutrality, bass definition/slam. You'd be surprised how many pricey, perhaps even famous, tube preamps do not meet the above definition. SAS 10A IS a "good tube preamp" in all its glory.

There's one thing I must complain about, however, which is the lack of IEC inlet to allow power cord swapping. (I include the jack now.) I am an admitted power cord junkie, and I can think of a few power cords that will minimize the upper midrange softness and add kick to low bass. For example, VH Audio cords will do exactly that for little investment. If I owned the 10A, I would definitely either DIY an IEC inlet, or hardwire a VH cord into the preamp. This combo will be scary good without question.

If I didn't have a system that was purpose-built around passive preamp (EVS), with whopping digital output voltage and 95dB sensitive speakers, I would own the 10A (with VH cord). It's just so musically engaging that this tube-rolling junkie didn't even try to roll any different tubes. FYI, That has not happened for any other tubed equipment that I've used ever..."

NOTE: All my preamplifiers now incorporate an AC IEC Jack, Standard. This allows for rolling power cords. My 10A also has an active stage of gain.

Second quick reviewer, (Earlmarc)

"First up, the SAS 11A preamplifer. Personally, I didn't think it was possible to better the 10A's performance. The 11A took it to another level. The degree of improvement is not in my opinion dramatic but is apparent. All the things I said in previous post about the 10A apply to the 11A, only the 11A increased the real factor to as close to live music as I have ever heard. Everything was more indentifiable and believable. The 11A is truly a reference preamplifier that I believe will stand toe to toe with the best of the best.

Second, the SAS Push/Pull KT88 mono amplifiers. Wow, what can I say. The best sounding amplifiers I've heard, especially when it comes to midrange magic. The palpability of images, the liviliness of voices, the air between notes, etc. I could go on and on about how shockingly real these amps sounded...."

I hope all continue to strive for excellence, as it can be obtained, so don't give up.

Caveat: I have been retired for some 8 years. I may start selling my “V” non shielded interconnects with 6n copper wire and gold plated, all copper RCA plugs again.

Please feel free to reply with questions.

Cheers

steve

Steve,
The mention of your amps made me wonder if Marty DeWulf or Richard Weiner ever reviewed them. I looked for your website, but it doesn’t appear to be active. If you have any pics or literature on the amps, maybe you could post.
Thanks,
Nick
Van Alstine SET 120 Control Amp
Audio Hungary APR 204 preamp
Fritz Carrera 7 BE speakers
Border Patrol SEi dac
Auralic Aries Mini & Mojo Audio lps
Audio Envy cables
Roon, Tidal, Qobuz
PI Audio UberBUSS

Online doug s.

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Re: I think my System is finally finished
« Reply #54 on: December 18, 2020, 08:52:09 AM »
steve, you shouldn't tease us like this, and then remind us you're retired.  you need to start making these again.

doug s.

Offline steve

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Re: I think my System is finally finished
« Reply #55 on: December 19, 2020, 07:35:31 PM »
My goal has been realized; that it is possible to design components with new stock tubes that can blow out NOS tube upgrades or NOS tube designs.

Referring to Dr. Weiner's list of preamplifiers (and more not mentioned), I think it is interesting to note that when Dr. Weiner first auditioned my 10A, it was the first time he had ever heard the recording studio wall reflections in a particular violin recording. He even asked his wife to confirm such.

That is true inner detail, revealing the backround of the venue, not harmonic distortion masking as inner detail.

I found a review from Earlmarc. Here is a portion concerning the 10A, 11A Line Preamplifiers, and 25PPT 2 stage monoblock amps.

"First up, the SAS 11A preamplifer. Personally, I didn't think it was possible to better the 10A's performance. The 11A took it to another level. The degree of improvement is not in my opinion dramatic but is apparent. All the things I said in previous post about the 10A apply to the 11A, only the 11A increased the real factor to as close to live music as I have ever heard. Everything was more indentifiable and believable...."

Second, the SAS Push/Pull KT88 mono amplifiers. Wow, what can I say. The best sounding amplifiers I've heard, especially when it comes to midrange magic. The palpability of images, the liveliness of voices, the air between notes, etc. I could go on and on about how shockingly real these amps sounded....."

More from my old 11A webpage. My website is down as my server has retired, but I might bring it back.

"Graham: "I took the B11a into a shop in Auckland. I know the owner fairly well, and we agree that Shindo make some wonderful pieces of kit. (I wasn't looking for a change!) Almost immediately we started listening, he said "That's really fast!" We also agreed that the B11a was much clearer, making the Shindo Aurieges sound slow, muddy, and coloured."

Terence: "I have been using the 11A since I received it but I didn't want to be premature in my assassment, although my initial assessments were favourable. Now, I must say that the 11A is certainly the best preamp I have ever owned, and the best I have ever heard-ss or tube. Thank you for a wonderful product, Steve."

Charles Phd, does musical reviews for PBS, Florida: "I just saw this post and you know I have to chime in here. After three years of preamp auditions I just pulled the trigger on the SAS 11A preamp. It was an unknown product to me but Marty Dewulf over at BFS (and who knows whats going on there these days, by that I mean it seems that Marty has slipped into retirement - forgive me Marty if I am wrong) Anyway he always said wonderful things about the preamp! So having no mind of my own I bought the preamp from Steve at SAS audio. The reason I bought the preamp is that I did not want to do the crazy audiophile thing of always upgrading. Buying the SAS preamp was the best thing I could have done. It's wonderful! Clear, fast musical and very truthful to the source. And more importantly it works well with both tube and solid state amps (i.e. Pass 30.5 & Audio-space 300b mono-blocks).

Bernie: "I have also tested the 11A in terms of comparing the sound from my excellent cd source directly to amps versus inserting the 11A pre between. I could detect no difference whatsoever.... So, my two cents: the SAS preamps are stellar – with my 11A I hear no compression or any other alteration of the originating signal."

George: "Steve,, this pre is "top shelf",, I currently have it thru odyssey mono se's to a pair of Carver Amazings,,, it's gonna be difficult for me to box it up and ship it on to Weez,,, organic, man,, organic,,, as soon as I receive the address, I'll ship it on,, I've got it "dialed in",,, it's so good,,it's scary---thanks for the opportunity to let me/us audition such a fine piece of gear---- george (George tested the 11A on tour.)

Charlie: "Steve,The overwhelming Majority of comments regarding the 11A during the tour have been very favorable. Everyone at Woodsyi's with the exception of Doug S who seemed to have prior issues with you because of you refusing to offer the 10A with a remote volume thought that the 11A was by far the best sounding pre of the bunch. DaveG sat there with Scotty and myself and fully agreed that the 11A was clearly the superior preamplifier out of the group."

Rich (Audio Circle): "I've been listening to a lot of preamps this week and even with the problems, it is evident to me that the 11A is in a different league. I'm glad I heard it first, because it set a high mark for the others to follow. The only other pre that sounds naturally musical so far is the Minimax with vintage 12AU7s. They are just too tubey though. But at least the sound is natural and tone is not all screwed up.....

Thanks Steve.
Rich"

Ray: "your prees are somewhat legendary in their reviews."

Jack: "My 10A is going to the grave with me, it's my favorite piece of audio gear. The 11A is better but they rarely come up for sale." (Jack auditioned the 11A at his venue.)

Bob: "Hey guys. . .if anyone's interested, I'm selling my Tram 2 preamp since my SAS B11A is so awesome...." (Tram 2 uses 45, 2A3s)"


My goal has been realized; that it is possible to design components with new stock tubes that can blow out NOS tube upgrades or stock designs.

Cheers

steve

« Last Edit: May 05, 2021, 07:30:37 PM by steve »
Steve Sammet (retired, owner, SAS Audio Labs)
"V" Very Low Capacitance ICs, 40pf 1 meter
SAS Audio Labs Test Phono Stage
SAS Audio 11A Tube Reference Preamplifier
SAS Audio Labs 25 W Triode Reference Monoblocks
2 way test Spkrs, 28 - 20khz  -3db (28hz)

Offline steve

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Re: I think my System is finally finished
« Reply #56 on: February 11, 2021, 01:01:02 PM »
steve, you shouldn't tease us like this, and then remind us you're retired.  you need to start making these again.

doug s.


It has crossed my mind Doug, but not strongly. I am currently testing one manufacturers capacitors. I could use
the 10A black chassis, but it is not the best, but it would keep the price down some.

How to label the knobs in front as my silk screener is retired. Of course there are only the selector, two volume controls, and the power switch. But no lettering in front or back, including warnings of shock inside?

The 11A would be the design I would wish to start again if I decided to.

cheers

steve

ps. I just compared two upgraded DACs and player to a Monarchy 24 tube DAC.

https://www.audionervosa.com/index.php?topic=8173.msg100860#msg100860
« Last Edit: May 05, 2021, 07:34:03 PM by steve »
Steve Sammet (retired, owner, SAS Audio Labs)
"V" Very Low Capacitance ICs, 40pf 1 meter
SAS Audio Labs Test Phono Stage
SAS Audio 11A Tube Reference Preamplifier
SAS Audio Labs 25 W Triode Reference Monoblocks
2 way test Spkrs, 28 - 20khz  -3db (28hz)