The celluloid discs were sold as a collection for Optigan owners and were mainly sustained organ sounds, as the continually spinning loops had no beginning or end it was impossible to create an attack or decay. The Optigan Music Maker. The most revolutionary musical instrument ever. And every combination. You've never heard anything like it because there's never been anything like it.
Organs try to mimic or imitate different musical sounds.
The sounds are on the Programs. Banjo Sing-Along to Nashville Country to Rock and Roll. It all depends on the Program and there's a Program for every musical taste. An unsuccessful 'professional' version of the machine was later marketed by a company called Vako under the name 'Orchestron', only about 50 were built and the company soon folded.