"Stewart Pinkerton" wrote in message
...
On Thu, 2 Mar 2006 20:17:00 -0000, "Keith G"
wrote:


Here's an interesting and well-written article that should have the
AntiSEpTics foaming at one or more of their body orifices:

http://www.stereophile.com/tubepoweramps/196wavelength/


This bit is particularly interesting:
"Then there's the interesting issue of distortion products. SETs include
even- and odd-order distortion products in their outputs (as in nature, so
to speak), while push-pull circuits cancel out even-order distortion by
design, leaving only the less musical odd-order products intact. Now
look...there's something to this. It's suggested that the sound of
single-ended triodes has much to do with their delivery-intact-of the full
spectrum of distortion products. "More distortion is better?" I hear you
ask. Well, it's less humorous than it sounds. Might "unnatural"
proportions
of odd-order distortion account for part of the sound of push-pull?
Something to think about."

... and should be read by those here who are continuing to confuse the
radically different terms 'realistic' and 'accurate'..

However, if you examine the distortion spectra of many good SS
amplifiers (carefully, because it's very small anyway), you frequently
find that the output distortion is dominated by the single-ended
voltage amplifier stage, so you have a decreasing low-order spectrum
dropping rapidly below the noise floor.

The difference with SETs is that you have a decreasing low-order
distortion spectrum which is well above the noise floor. This
nonlinearity also produces high levels of intermodulation distortion
which do nothing but muddy the sound.



There are any number of interesting sites that deal with distortion in
triodes like this one:

http://www.triodeel.com/ptnotes.htm

Who knows? One day I might even get round to reading some of them, but until
I know better I'll stick with a sound which is (IMO) anything *but*
muddy....