The Black Hole......

Chester,
Even if this SE amp sounded just as good as a well designed SS amp, it would be a reason to be surprised given the huge THD.
I can’t imagine in case the SE amp had sounded bad, that positive reviews could have been published.
One shouldn’t be naive, but not even considering that there may be some truth in this could also be a prejudice.

Hans
 
e has made a point with the SE tube amp with horrible THD figures but excellent IMD results and very positive reviews in audio magazines.
IMO reason enough to give it some thoughts.

Hans

it does come close to agreeing with what some professional high end audio designers believe..


Now the problem is that, if you look at plenty of reviews and interviews you will find pretty much any topology has a 'professional high end audio designer' (whatever that is) who believes in it and a reviewer who will give it top marks.


But I will agree that there is more love for SET amplifiers than one might imagine given the generally horrendous efficiency and awful measurements that is at least intriguing to investigate.
 
I think what we need first is convincing evidence that at least some people,
You mean relevant evidence. Because if it's non-relevant evidence to the claim, it won't be convincing no matter how solid that evidence is.
Even if this SE amp sounded just as good as a well designed SS amp, it would be a reason to be surprised given the huge THD.
Sounding good is in the ears of the beholder. In self-fi world, anything goes. It doesn't even need any standards.
 
Who posted such statement?

The SICRAP comparison graphs for example.

They clearly show the evolution of the audio reproduction along the last 50 years (old poor quality at the left against superb contemporary quality at the right.).
 

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the basement isn’t as dark as you thought.
These days measurement tools are affordable. Comparing how people like a particular sound relates more to the acoustic THD. It is confusing to compare how different amp THD sounds when the speakers being used are different. What I suspect is that high THD SE amps will not sound good on more commonly available low THD speakers and vice versa.
 
I think he has made a point with the SE tube amp with horrible THD figures but excellent IMD results and very positive reviews in audio magazines.
IMO reason enough to give it some thoughts.

Hans

To have horrible THD and excellent IMD is impossible by nature. THD or IMD are only different means how to have a look at the same nonlinearity. Plus frequency dependence of this nonlinearity.
 
@PMA
True for time-invariant nonlinearity (or stationary one), not necessarily true for systems that are changing linearity dynamically (like some tube circuits and or some class-D).

So you would be saying that the burst non-linearity function with a sine or a twin-tone in "some tube circuits" would considerably differ, right? Any proof here? Anyway any normal SS power amp will have the nonlinearity in orders lower than the power tube amp. Usual junk.
 
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To have horrible THD and excellent IMD is impossible by nature. THD or IMD are only different means how to have a look at the same nonlinearity. Plus frequency dependence of this nonlinearity.

Pavel, For amps with substantial amounts of feedback I fully agree.
But in case of having none feedback at all I have no idea, that's why I will attempt to do some LTSpice sims, maybe leading to get a better feeling.

And at the same time, when you are right for this special case , the Uni of New Hampshire has agreed on the publication of a 86 pages paper with completely wrong conclusions based on completely wrong measurements and assumptions.
How likely is that, would be bad for their reputation.

Maybe someone like Syn08 could shine his light on this, one of the few whose knowledge I trust.

Hans