"Trevor Wilson" wrote in
message

"Andre Jute" wrote in message
oups.com...

True. A great advantage, much more pleasant than the odd
harmonics of PP even when the latter is at a much lower
absolute level.

One might try to compare SET and PP by comparing two amplifiers, one a SET
and the other a PP amp built up by running two SETs identical to the first,
in PP.

Now let's compare these two amps that differ only in that one is PP and the
other is SET. Let's further stipulate that listening levels will be kept
low, so that any power advantage of the PP amp is nullified.

We find that the SET puts out its usual mixture of even and odd-order
distortion. The PP setup will internally cancel out the even order
distortion, leaving only the same odd order distortion that the SET
produced. From the stand point of production of odd order distortion, the
two amps are identical. The SET differs in that it also produces even order
distortion.

The SET amplifier therefore provides no meaningful advantage from the
standpoint of reduction of odd-order distortion. It simply produces more
even-order distortion.

It is well known that amplifier nonlinearity whether odd or even order does
not produce only harmonic distortion. Amplifier nonlinearity produces IM
distortion. Even order nonlinearity is an especially effective means for
producing intermodulation products. IM distortion is almost guaranteed to be
non-harmonic and therefore very irritating to listen to.

In addition to producing less over-all distortion, the PP amplifier will
also produce less IM distortion than the SET amplifier.


**Huh? In which universe do you imagine that higher
levels of distortion will lead to greater fidelity?

The universe of SET hysteria, of course! ;-)