Tonewheel organ synthesizer for an Arduino and a MidiVox shield
C Arduino
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roto is a sound synthesis program that mimics a tonewheel-based organ,
similar to a Hammond B series. It runs on an Arduino board with a
MidiVox shield:

It supports drawbar changes on MIDI CC# 110-118.

This is in an early stage of development. Drawbars have not been
tweaked to sound like an actual organ, and there is no vibrato,
percussion, or emulation of a rotating speaker cabinet.

There is a small glitch when notes are started.

Its performance degrades when many notes are played at the same time,
and no provision is made for limiting the number of notes in the
code. Play too many and you'll get unpleasant distortion.

This depends on the number of oscillators that are in use, which can
be controlled by the drawbars. Sticking to the classic 888000000
drawbar setting (roto's default) will leave you with a decent sound
and enough disabled oscillators (the 0's) to be able to play a few
notes at the same time.