Live music, Tone and Presence: What most systems get wrong

[KeithR]

What does correlate with sound quality is the harmonic structure of the distortion that is generated...the order of the harmonics and their relative and absolute levels. This has been known at some level since the 1930s but was largely ignored once negative feedback pushed all naysayers away into a THD arms race.

Nelson Pass thinks different - his anecdotal studies have a third of folks preferring 3rd harmonic. These are probably the same folks like Frantz that find an unnatural "beauty" on many SET amps. I have to admit my last two SET demos had me thinking similarly.

http://www.firstwatt.com/pdf/art_dist_fdbk.pdf

I'm not saying there is a right or wrong way - but I don't think its as simple as you think. I also don't think there is a THD arms race in 2016. Many high end amps use little to no negative feedback as well.

I also *strongly* believe in amp/speaker synergy and an amp that may sound great on one speaker, doesn't work on another. Luxman Class A, for instance, sounded like cream on my Zus - but works very well for Vivid speakers.

 

[853guy]

But you can go to the very pinnacle of loudspeakers and not get realistic sound of any kind with mediocre electronics. That is because distortions from electronics are wholly unnatural and outside our evolutionary experience. Speakers are largely mechanical things that makes distortions that our evolutionary experience can still relate to and accept more easily. Therefore, getting that right, is both harder and more important, IMO, than the speaker choice. To get to a very high level requires both of course.

Speakers have crossovers that are not mechanical things and introduce distortions, e.g., phase shifts, that our evolutionary experience also cannot relate to.

I agree with Al M.

Semantics, maybe, but speakers are electro-mechanical devices that interact with the amp driving them. As such, it makes more sense to think of the speaker and amp as an electro-mechanical entity in itself, creating an interdependent, non-linear and asymmetrical relationship.

 

[microstrip]

Speakers have crossovers that are not mechanical things and introduce distortions, e.g., phase shifts, that our evolutionary experience also cannot relate to.

IMHO our evolutionary experience have been dealing with phase shifts since its beginning ...

 

[Al M.]

IMHO our evolutionary experience have been dealing with phase shifts since its beginning ...

Hehe.

 

[bonzo75]

I agree with Al M.

Semantics, maybe, but speakers are electro-mechanical devices that interact with the amp driving them. As such, it makes more sense to think of the speaker and amp as an electro-mechanical entity in itself, creating an interdependent, non-linear and asymmetrical relationship.

As long as the amp is a SET. Any car as long as it's black

 

[853guy]

As long as the amp is a SET. Any car as long as it's black

Is this humour at my expense? Some in-joke from a film I haven't seen?

I'm fine with it being either or both, but I don't really get it. Or is the point that you're making that I don't get it?

Love and hugs, etc...

 

[bonzo75]

Is this humour at my expense? Some in-joke from a film I haven't seen?

I'm fine with it being either or both, but I don't really get it. Or is the point that you're making that I don't get it?

Love and hugs, etc...

Not at your expense.

 

[853guy]

Not at your expense.

Oh, yes, I see what you did there.

 

[bonzo75]

Oh, yes, I see what you did there.

The car as long as it's black is a Henry Ford dialogue.

Just thought some people want the same color in any case, sometimes at the cost of performance

 

[853guy]

The car as long as it's black is a Henry Ford dialogue.

Just thought some people want the same color in any case, sometimes at the cost of performance

Actually, if I had taken some time to think it through before posting so hastily, I probably could have put it together. I blame it on the pizza (goats cheese and prosciutto, if you must know).

 

[bonzo75]

Actually, if I had taken some time to think it through before posting so hastily, I probably could have put it together. I blame it on the pizza (goats cheese and prosciutto, if you must know).

Brad, please stop eating pizza and you might put it together.

 

[853guy]

Brad, please stop eating pizza and you might put it together.

About to be followed up by Häagen-Dazs. (It's cheat night, so I've gone all in.)

 

[morricab]

Nelson Pass thinks different - his anecdotal studies have a third of folks preferring 3rd harmonic. These are probably the same folks like Frantz that find an unnatural "beauty" on many SET amps. I have to admit my last two SET demos had me thinking similarly.

http://www.firstwatt.com/pdf/art_dist_fdbk.pdf

I'm not saying there is a right or wrong way - but I don't think its as simple as you think. I also don't think there is a THD arms race in 2016. Many high end amps use little to no negative feedback as well.

I also *strongly* believe in amp/speaker synergy and an amp that may sound great on one speaker, doesn't work on another. Luxman Class A, for instance, sounded like cream on my Zus - but works very well for Vivid speakers.

The key word in your opening sentence is "anecdotal". Most of his first watt stuff is making more 2nd harmonic anyway...especially the vaunted SIT amp, which is a single transistor per channel.

The whole point of my OP was that this unnatural "beauty", as you call it, was what I heard at the concert sitting less than 3 meters away from two cellos sawing away. It didn't remind me of ANY system I have heard that had a SS amp. Not one. Not Luxman Class A for sure...not Pass Class A, not Vitus...not.

Many top high end amps use a lot of feedback still: Soulution for one. The Class D mola mola for another.

Amp/speaker synergy does matter...especially if the amp has a lot of negative feedback and the speaker produces a lot of back EMF. That is probably more important than impedance per se or sensitivity.

 

[morricab]

I agree with Al M.

Semantics, maybe, but speakers are electro-mechanical devices that interact with the amp driving them. As such, it makes more sense to think of the speaker and amp as an electro-mechanical entity in itself, creating an interdependent, non-linear and asymmetrical relationship.

This is especially true of an amp with negative feedback where back EMF can be injected into the feedback loop and then that distorted signal gets amplified along with the original signal. Matti Otala did a paper on this in the 80s, I think. An amp without negative feedback, at least around the output stage, is far less susceptible to what the speaker is doing because there is no path for the back EMF to interfere with the forward coming signal. In a transistor amp though the back EMF can be severe enough to overheat the output stage (electrostatic speakers send close to 100% of the signal back to the output stage thus forcing it to dissipate much more energy than originally designed).

 

[morricab]

Brad, please stop eating pizza and you might put it together.

So you have nothing meaningful to say and you resort to attempting some snide back handed humor? If you will stop and think, you might realize that I am the one advocating more color to your listening instead of lean and mean. So, your Ford analogy falls flat...probably like your sound system!

 

[the sound of Tao]

We are a bit caught in a loop on this and it would be great to find some new ground here. The original premise promised that but now we seem to be just going over exactly the same territory as in so many threads that have tackled the unveiling of the magic in SET and for some also the potential compromises with SET.

You just can't fairly evaluate the qualities of an amp out of context with its speaker pairing. I don't believe that SET used in a less than ideal speaker partnership is likely to result in anything but a lovely but still less than ideal sound. It seems to me harder to undo the underlying musicality by putting SET into a less than ideal speaker pairing than it is to damage the overall sonic integrity of the presentation. That is to say SET is for me largely inherently musical but also not necessarily life like in all parameters of its presentation of sound. It is more obviously less life like on larger full range ribbons than it is on horns, or on other high efficiency boxes, or even on hybrid panels or panels run with subs.

It doesn't tend to smear the sound in the core of its range but this can often also be somewhat less convincing at the extremes. In an ideal pairing like with horns this is hardly noticeable because what it is doing right is just so right. Horns don't tend to show you the last fragment of minutiae. They give you the big picture and so much of it that you don't notice details nor feel compelled to look for them. Both horns and SET don't trip over when caught up in the flow of the music. They get out of the way of the music and just let it into the room.

Put the same amp on a set of ribbons and sure, the mid range is still wonderous (and sometimes a tad too wonderous given how it then highlights the slightly less wonderous extremes). Not only can that coherence issue be highlighted by the greater linearity and resolution of ribbons it will also be exacerbated by the traditionally more demanding load charactertics and considerably lower sensitivity of this type of speaker. Also, it's in the nature of full range ribbons to not just show you what is there but also to them remind you of what is so clearly perceived as missing.

What was a lesser constraint with horns becomes a much more obvious constraint on the ribbons. Not too say some very specific higher wattage SET with large iron can't do better at this but then for me the shift of valve types to get this also involves other compromises. In the end while it can be undeniably pretty it fails to make the partnering ribbons do what I feel they do best... coherency and wholeness throughout their range with a broad versatility in being fairly wonderful at playing many types of music.

Given that there are a couple of breeds of speakers that are fairly ideal for SET then enjoying the best qualities of this amp type isn't a problem. Like others here, I feel that SET and horns is the happiest of SET marriages and is so very easy to get engaging presence with some of the more natural and beautiful tonality possible. But I also feel that this marriage has other other very salient issues. Mainly that this combination in its purest iterations can then also tend to limit us to the types of music that will work best with them. A happy marriage in a very lovely musical niche.

 

[bonzo75]

Which Luxman class A did you listen to, Brad, and on what speakers?

 

[morricab]

Which Luxman class A did you listen to, Brad, and on what speakers?

L550ax on a pair of Tannoy Keningtons and a pair of bridged m-800as on the Vivid Giya G1.

 

[bonzo75]

L550ax on a pair of Tannoy Keningtons and a pair of bridged m-800as on the Vivid Giya G1.

And what did you compare the 800 with?

 

[FrantzM]

The key word in your opening sentence is "anecdotal". Most of his first watt stuff is making more 2nd harmonic anyway...especially the vaunted SIT amp, which is a single transistor per channel.

The whole point of my OP was that this unnatural "beauty", as you call it, was what I heard at the concert sitting less than 3 meters away from two cellos sawing away. It didn't remind me of ANY system I have heard that had a SS amp. Not one. Not Luxman Class A for sure...not Pass Class A, not Vitus...not.

Many top high end amps use a lot of feedback still: Soulution for one. The Class D mola mola for another.

Amp/speaker synergy does matter...especially if the amp has a lot of negative feedback and the speaker produces a lot of back EMF. That is probably more important than impedance per se or sensitivity.

morricab

Your recollection is also "anecdotal" there is no fact to it. It could be sincere but is is not factual. A point of view that I can only admit as being sincere. I remains nonetheless an opinion