Tom Henry Tunable Noise Source

Sean Costello costello at
Fri Nov 12 21:43:44 CET 1999

WeAreAs1 at wrote:
> The new noise source derives its noise from the standard reverse-biased
> transistor, but then uses this noise to modulate (FM) an LM566 VCO. 

Cool! Is there user-controllable filtering of the noise that is used to
modulate the VCO? If the noise is processed by a lowpass filter before
FMing the VCO, the cutoff frequency of the filter will control the
"width" of the noiseband, while the VCO frequency will control the
center pitch of the noiseband.

Has anyone tried a similar patch with a slewed S&H noise source? A S&H
module clocking a noise source, with the output "slewed," would be
essentially identical to the RANDI function which can be found in
various computer music languages.

Sean Costello

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