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Re: P.S.

I have test measurements from an independent Dutch magazine that shows that the smaller brother of the amp I am using has at 1 watt only to 5th harmonic above the -125 db level. The 4th and 5th are at -95 db and -105 db the 3rd at -75 db and the 2nd harmonic at -50db.

At 10 watts this amp has more harmonics above the -130db level.
2nd -40db
3rd -55db
4th -70db
5th -85db
6th -90db
7th -105db
8th -110db
9th -115db
10th -110db
11th -115db
12th -120db

As you can see the results are not bad at all for any amp of its power rating and most SS amps have higher levels of higher order harmonics at this power (and more damning at lower powers where my amp gets more and more linear...crossover distortion...its a bitch). Also, above 4th harmonic the levels are still very low even at 10 watts (a lot for a typical SET and plenty for most music listening with reasonably sensitive speakers).

Again, bandwidth is 80khz (-3 db) and damping factor is about 5.5 (fine for all but crazy impedance curves). Distortion vs. frequency is nearly flat.

You are right about one thing, Push pull tube amps with negative feedback do indeed often more give higher order harmonics. They also often give predominantly odd order harmonics like most SS amps (due to even order cancellation from being push pull). Also, tube amps with poorly designed output transformers will have high distortion in the bass usually. This is not endemic to the design but indicative of a poor output transformer choice. Finally, a poor driver stage can generate a lot of distortion as well. It is true that a no feedback amp is more sensitive to these things but with careful design and execution the problem is largely solved not doctored with feedback that really doesn't solve the problem of inherent non-linearity.

Just like you would say that most SS amps are likely poorly designed, so too are many tube and hybrid amps. That doesn't mean the whole class of amp is damned it just takes talent to make it work correctly. IMO, the result sounds better because it makes less offensive distortions...and I think this is largely due to the relative absence of negative feedback.

"that most audio perverts like yourself, call "musical" "

I never call muddy sound musical, Dan. I call muddy sound muddy, and grainy sound grainy etc. In fact I believe there are two types of distortion, the kind you can hear and the kind you can't. If you can hear it then it degrades the sound...period. If you can't hear it then its like it isn't there at all. Doesn't matter if it is 0.00001% or 10%, if you hear it you hear it and if you don't then who cares if its there? If a tube amp sounds muddy then it is clearly making audible distortion. I don't abide by this because I know what real instruments should sound like, period. If an SS amp sounds sterile or grainy in the highs then I don't abide by it because that too is distortion. The question then is which type of distortion is less annoying. The amp I have now, at reasonable levels, has to my ears nothing in the way of distortion. It is one of the only ones i have heard this clean without being etched or sterile.

Actually the fact that such amps are on the rise should give you pause to wonder why people are preferring the sound. After all, according to your design philosophy, we have had perfect amps for at least 25 years. Some have thought about this and come up with better sounding designs. Fossils like you are not flexible enough to question your own philosophy so it is no wonder you rage against the wind, which has shifted direction away from your philosophy. There is a backlash for a reason and its not because we are all degenerates and you are somehow the perfect rational human. Rather it is probably the reverse.

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