Rhythmicon

The Rhythmicon—also known as the Polyrhythmophone—was an electro-mechanical musical instrument designed and built by Leon Theremin for composer Henry Cowell, intended to reveal connections between rhythms, pitches and the harmonic series.

[1][2] In 1930, the avant-garde American composer and musical theorist Henry Cowell collaborated with Russian inventor Léon Theremin in designing and building the remarkably innovative Rhythmicon.

The instrument produces its percussion-like sound using a system, proposed by Cowell, that involves light being passed through radially indexed holes in a series of spinning "cogwheel" disks before arriving at electric photoreceptors.

In October 1931, in a letter to Ives from Berlin, he said, "I have been composing and have finished the second movement of my work for the Rhythmicon with orchestra for Nicolas to use in Paris in February.

The Rhythmicon was publicly premiered January 19, 1932 by Cowell and fellow music educator and theorist Joseph Schillinger at the New School for Social Research in New York.

[8] On May 15, 1932, a New Music Society concert in San Francisco[9] included – along with the premiere of Xanadu, a new work by Mildred Couper – a demonstration of Cowell's new instrument.

One of the original instruments built by Theremin wound up at Stanford University; the other stayed with Slonimsky, from whom it later passed to Schillinger and then the Smithsonian Institution.

More recently, composer Nick Didkovsky designed and programmed a virtual Rhythmicon using Java Music Specification Language and JSyn.

The performance featured a reconstruction of the Rhythmicon played, designed and built by Mike Buffington for multi-instrumentalist and composer Wally de Backer.

Joseph Schillinger and the Rhythmicon (1932)
The third Rhythmicon constructed by Theremin