This video, via wildchurch, demonstrates a DIY recreation of the very rare Kawai School Rhythmer, an educational rhythm machine from the 1960s.

The Kawai School Rhythmer lets you create custom rhythms using pegs inserted into a matrix, representing the steps of a beat. It features five percussion sounds, Triangle, Japanese Woodblock, Cymbal, Small Taiko & Big Taiko.

This DIY version is based on the circuitry of a 1970s DIY drum machine kit produced by the Japanese company, Elekit. The remaining circuitry is built around 4017 chips and a 555 timer for the internal clock.

The peg matrix involves microswitches, such that, when a peg is inserted, the signal passes through, triggering a drum sound on that particular step. While this DIY version has a retro futuristic vibe, the original, below, was more minimalistic.

Here’s an original School Rhythmer in action:

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