tube amps and electrostatics

Some cannot see the forest for the trees.

Martin Logan ESL Montise sterophile review, driven by Audioplax 80w tube monoblocks, also by ProLogue tube Premiums, and then by Simaudio Moon Evo 7's solid state.

Quote from the measurements by JA:
"The shape of the impedance trace will result in the Montis's top octaves shelving down when the speaker is driven by a tube amplifier having a high source impedance. This is why Robert Deutsch found that his Audiopax amplifier sounded too soft and lacking in definition."

Quote from the Robert Deutch review:
"The other tube amp I had on hand was the Audiopax Model 88 Mk.II. The Audiopax driving the Avantgarde Uno speakers is a "magical" combination: detailed and transparent to the source while minimizing the "electronic" artifacts of the reproduction process. The Audiopax-Montis marriage was not a happy one. Although the Model 88 Mk.II's rated output is 30Wpc—not that much less than the ProLogue Premium's 40Wpc—the Audiopax was dynamically on the subdued side even at moderate levels, and the sweetness and liquidity that had been so appealing with the Avantgardes now came across as too soft and lacking definition.
Next up was the Simaudio Moon Evolution W-7, a 150Wpc solid-state amp. The sound of the Montis driven by the Moon W-7 was vastly different from its sound with the PrimaLuna or the Audiopax. It now had dynamics in spades, evident as an ability to play much louder without strain, as well as more clearly present the ebb and flow of music at moderate levels. Bass was more extended and better controlled; the double-bass passages in Sylvia McNair's Sure Thing: The Jerome Kern Songbook (CD, Philips 442 129-2) were more distinct."

I have asked Roger Sanders to come to this disscusion he has cred both in ESL's and amplifiers to drive them with, so I hope he will respond. It's was posted here that he of course is biased towards his own S/S amps for esl's, but that was quickly edited out, why was that????

Cheers George

Ralph- Save your keystrokes.

I'll stand on my position that technical specs never tell the
whole story, and any given reasonable combo of gear, even with
electrostats, can win on any given day. Too many other
factors come into play. no substitute for listening and
hearing. Tube sound lovers will probably still like the tube
amp sound for the usual reasons and vice versa. Neither will
likely hold all the cards always. Like usual. Good sound is
shades of grey usually, not black and white.

George, I happen to enjoy reading many of your posts in other threads. But I feel compelled to politely suggest that Ralph Karsten (Atmasphere) and Al (Almarg) are among the most respected A'gon members. Both are EE techies. And Ralph is the gent behind Atmasphere as in the "designer" and maybe the owner too.

In short, you're taking on some pretty heavy-duty guys. I suggest you back down and carefully re-read what Ralph and Al posted. I happened to think that what they wrote makes sense.

Ralph and Al, the discussion begs the question of how can one know whether an ESL was voiced to be driven by a tube versus SS amp. Obviously Sound Lab ESLs were designed to be tube friendly, ergo Ralph's comment that his amps have been coupled with Sound Lab ESLs for years. Is it the same old answer -- call the manufacturer and ask?? Or try to determine the type of amp that was used by the manufacturer to display the ESLs at shows??

Seems to me that what gets a bit dicey is the case where the ESL is coupled with a cone/dynamic speaker to cover LFs. Then we're back in the soup with "rock and roll" impedance curves.

Folks, let's try to remember this is a just a cool hobby and we're all friends.

Cheers,

Bruce

Al, I don't mind; and, thanks. I think your comment "Which of those two kinds of amplifier/speaker interactions results in the most correct acoustic output from the speaker is a separate question, however." is particularly valuable and relates to another issue that you bring up, perspective.

As I said previously I tend to let those more technically astute explain these interactions, but after a lot of years in this hobby I am convinced that part of the reason that some of us "are at loggerheads" (besides ego and stubbornness) is that there are still aspects of sound and music and the perception of those that the technical doesn't fully explain. I would like to offer some thoughts about this from my perspective.

In my experience, and almost without exception, systems assembled with the stated goal of "linearity" don't sound the way that live music sounds. More times than not the result is sound that is tipped up in the highs and lean through the midrange compared to the sound of acoustic instruments. The argument that there is too much variability in the sound of live to establish a benchmark is nonsense; there is much more that is consistent than there is that is different. Most of music takes place in the midrange and most audiophile systems sound too lean in this range without enough fullness and image density particularly in the lower midrange. I can't remember how often I have heard comments about a system lacking bass when there really was no true bass content in the music and what the listener was missing was the appropriate fullness in the lower midrange and, perhaps, upper bass that gives music much of its power. "Linear" highs will often result in upper partial information that is not well integrated with the fundamental frequency and add excessive "presence" to the highs.

"Brightness" is an interesting descriptive term in that it is often confused with "texture". I have heard many systems (or recordings) that are described as "bright" which I would describe as harsh or grainy but definitely not bright. In fact I have heard systems that are dark and harsh (usually ss based) and others that are bright and overly smooth (usually tube based). Incorrect texture is what I hear oftentimes with ss amps driving electrostats and not necessarily excessive brightness (even when the sound is too lean, giving the illusion of brightness), and that is the main reason that tubes driving electrostats usually sound more natural to me: the fullness and image density of the midrange and the proper integration of harmonics with their fundamentals creating a texture and clarity that is much closer to the sound of live acoustic instruments even if, in absolute terms, the sound does not measure as "linear"; whatever that is.