Class A, B, C? What do they mean?

Sean: In power amplifiers operating at radio frequencies distortion of the rf waveform is relatively unimportant.
RF amplifers usually operate with tuned circuits and the
selectivity of such circuits filter out the rf harmonics resulting from distortion. Of course, a wideband class C
amplifier has tremendous amount of distortion, because the
operation angle is less than 180 degrees. A push-pull
amplifier operating at pure class B is exactly 180 degrees
and you take the the two waveforms one from the push and
one from the pull and add to give a 360 degree waveform.
A class C amp since each side of a push-pull is less
than 180 degrees can never give a 360 degree waveform, thus
the huge amount of distortion. A Class A amplifiers since
by definition gives a 360 degree waveform,does not need
a push/pull to define a full waveform. You only need one
output tube for class A operation, two for class AB or B
operation

Using tuned "tank circuits" on tube gear and harmonic traps on SS gear will help to reduce THD, but that does nothing to get rid of IMD or "in-band splatter" when using a Class C amp. Class D will also suffer from this, but with slightly different results that would vary with design. All of these "problems" occur in audio amps using these design variations also. Sean
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Sean: Have you ever seen an AF Class C amplifier? I have not. RF amps, in particular, pulsed nuclear magnetic resonance instrumentation, I have seen many. Ham operators,many. Nada for audio.

No, i've never seen a Class C amp for audio. My main comments in my last post regarding audio amps pertained to Class D amps. Sean
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I think the new Rowland Amp 301 is a class D or H switching
amp. So how does an audio company who makes class D amps
get around these problems. I assume the faster you oversample the better, but how much I am not sure. I assume
you would have to decimate the data back into the audio
frequency, again I am not sure. Does anybody know????