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Re: I can't see the distortion for all the harmonics .....

Hi Duke,

Well, not just emitter follower linearity. More trying to get
data to support why certain circuits sound better than others.

Current thinking (at least mine) is to greatly limit how much 7th,
11th, 13th, and higher harmonics are being produced. Don't care so
much about lower harmonics as long as they aren't out of control.
Another criteria is masking. If an odd harmonic is hi in level, then
want to see the next lower even harmonic that will cover it. For
reasons why to all of these criteria, you'd have to look at past
threads.

The use of different types of emitter followers is to search for
some data that might show distortion problems as the culprit. For
single tone tests, this turned out *not* to be the case. The only
clue that turned up was by doing frequency sweeps and seeing
instability at higher frequencies in the Sziklai, and a small amount
in the Darlington. So far, a tube cathode follower has the best
residual distortion of any of the followers (although to be fair,
it isn't capable of the same hi power).

So wanted to get a test that could translate into a measurement
and produce some meaningful results as far as distortion goes.
I received JC's paper on TIM measurement and it turns out to be
quite clever. It is a test that is designed to expose a circuit to
TIM effects unlike two tone, and large signal tests. It turns out
that you can actually seperate the static IM from the dynamic IM
(TIM) by flipping the square wave to a triangle wave. This is very
easy to do. So I think this test might have some resolving power that
will be interesting to see what happens. All of this is in simulation
of course.

Mike

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