Optigan Disc Singing Rhythm
Condition Excellent Sleeve & Disc
Vocal group to accompnay the melodies of your choice.
Rhythm 4/4
Left Hand: Vocal group with vibraphone, piano, bass, guitar & drum accompaniment.
Right Hand: Organ

The Optigan is an electronic keyboard instrument designed for the consumer market back in the 70's. The name stems from the instrument's reliance on pre-recorded optical soundtracks to reproduce sound.

The Optigan's playback system functioned much like the storage and reading of an optical soundtrack as was used in motion pictures, using a light bulb to energize a row of photodiodes on the opposite side of spinning, 12" diameter clear plastic film discs (officially referred to as "Program Discs") encoded with fifty-seven concentric optical tracks. The system then translated the analog waveforms on the disc to an audio signal.