[sdiy] Imperfect VCO

[Grant Richter]

> Anyway, with wave distortion or mangling you get static
> harmonic waves. Most of these will not make you jump and shout.

Static waveforms are pretty boring. To some extent you could say an entire
synth is really a waveform animator.

Producing waveform animation by the use of filters (which change the
waveform in the frequency domain) has been pretty well explored.

Producing waveform animation by the use of non-linearities (which are
computed in the time domain) has been explored much less.

But we know it can sound great, because of the Buchla Music Easel (3
reverses waveshaper) and Serge Wave Multiplier (4 reverses waveshaper).
Varying the amplitude of a sine (or tri) wave into these sounds very nice.

Also the Blacet VCO has a nice non-linear waveshaper with voltage control.
And Paul Schrieber has a math module which can be used as a non-linear
waveshaper.

Any other pure analog designs in commercial production?