Wave Wraper

[Thierry Rochebois]

>1.  There was a "valve distortion" effect in E&MM magazine that
>     used a 13600 and a sidechain to reduce the instantaneous
>     gain of the signal with increasing level.  The sidechain was taken
>     from before the 13600, so it was possible by incorrect setting of
>     threshold and sidechain gain to make the waveform fold back
>     on itself.


That's a good Idea. The peak level of the signal would be smaller and it can
be post compensated.

>2.   Elektor did a guitar FX unit which did wave folding.

That's the right stuff ! I think it is possible to chain many units to
obtain what I want.
Thanks very much !

>A further thought - althought the overall signal level will be
>reduced with wave folding, the actual rate of change of
>voltage will remain the same - so maybe the perceived
>loudness will remain constant.  I hope that's right - my
>own waveshaper design causes a loss of signal level with
>increased processing too.

I own a Clavia micromodular synth which includes this kind of
effect. As it is digital and as this effect adds bunches of harmonics,
it aliases !
As far as I know the result is very similar to Frequency modulation :
You obtain timbre variations and you loose the amplitude variations
(sort of compression). Thus, one can detect the original enveloppe
and applies it back to the processed sound.

Kind regards and thanks a lot,

Thierry Rochebois