Recently I discovered and bought The Noise Generator Cookbook by Thomas Henry, available at Lulu.com.  I recommend it!  Includes a great bibliography, too.  In addition to learning what white and pink noise really are, and reading all about noise generator circuits for synthesizers, this spurred me to spend some quality time with the noise generators in my own synthesizer.  I’ve got a MOTM-101 Sample and Hold with white, pink, and slow random outputs.  And a Blacet Improbability Drive with white and sampled white (‘digital’) outputs, plus a 12db lowpass/bandpass filtered (i.e. not pink noise) output.  I had also included a DIY white noise generator for internal sampling use with my CGS Infinite Melody.  The Modcan VCDO has a wave bank dedicated to pseudo-random voltages.   All of these noise source sound different to the ears and look different on the ‘scope.  For instance, the MOTM white noise has a lot more high frequency components than the Blacet white noise.  (The MOTM and Blacet white noise circuits are proprietary variants of two different circuits described in Thomas Henry’s book.)

The VCDO noise bank is especially interesting.  First, it’s a voltage-controlled noise generator that goes from a pink-sounding noise at the highest frequency of the oscillator all the way down to slow meandering voltages in LFO mode.  Second, the internal FM capability of the VCDO also affects the noise bank, affording even more varieties of noisy sound.  I was wondering how to apply this feature and hit on the idea of using it as a modulation source for the through-zero FM of the Teezer VCO.  Well, that’s the basic patch here.  VCDO out to Teezer linear FM in, AC coupled.  I used the triangle output of the Teezer into my MOTM-480 resonant filters.  This is the result.

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