I have long been a fan of tape-based instruments and was (still am) fairly obsessed with optical playback keyboards like the Optigan, Orchestron and Talentmaker. There's no real emulation of the Optigan other than using VST software (none of which work quite right).
An Optigan disc contains 20 musical loops that correspond to 26 physical buttons. These buttons, when pressed, allow light to pass through the disc and into an optical eye. This is like a reverse mute. I am achieveing this reverse mute using SysEx commands.
My first design attempted to run all 20 loops at once. Unfortunately, the MS-1 only allows 14 simultaneous loops playing at once. I can only get Midi Designer to play 8 notes at once, for an unknown reason.
Here's what I have so far:
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