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Subject: Hot patch

From: "Dave Bradley" <daveb@...>
Date: 2000-02-29

I snipped this from AH yesterday and tried it last night. Large amusement,
although I'm not sure it is in fact technically a Sheppard function!

Dave Bradley

You can also make "shepard sequences" with (2) LFOs modulating one (or more
Use one positive-going sawtooth LFO and one negative-going sawtooth LFO.
Set the LFO rate for both of these to approx 3Hz or higher (as close to the
same rate for both LFOs as you can, but don't sync them - you want them to
slowly beat against each other).
Route both of these (as modulation sources) into an oscillator - making sure
that you can carefully adjust the modulation depth from each LFO
Now, while adjusting the relative depths of mod from the LFOs - you will
eventually reach a point (a balance point) where the modulated audio
oscillator sounds like it is changing in pitch in discrete steps (rather
the "whoop - whooop" you normally get with sawtooth modulation).
This is the "sweet spot."
Now - detuning one of the LFOs will cause the shepard sequence to
cycle upward or downward (depending on whether its frequency is sharp or
relative to the other LFO).
Note that changing the rate of one of the LFOs requires that you reset its
relative modulation depth to get back to the stepped-modulation.
You can get a ton of different "sequencer sounding" patches this way.

Have fun!