The history of vacuum tubes in synthesizers goes all the way back to 1939: the Hammond Novachord, one of the first polyphonic synths ever commercially manufactured, relied on an array of 163 vacuum ...

Eurorack has taken over the synthesizer community ... on a piece of paper glued to a stepper motor. The key bit of mechanism for this build is a stepper motor with 96 steps per rotation.

[Rich Bernett]’s Cassettone cassette player synth. The Cassettone works by substituting the trim pot that controls the speed of the tape player’s motor with a handful of potentiometers.