Optigan is DSP Bricks' software recreation of the Optigan, the optical-disc home organ Mattel sold from 1971. Rather than sample a handful of notes, it models the whole instrument: the lead keys, the chord and rhythm buttons printed on each disc, and the tempo, reverb and balance controls of the original panel.
The library is the draw. The plugin ships with all 40 program discs that were released for the hardware, three unofficial prototype discs, and multiple revisions for fifteen of them, so the character shifts completely from one disc to the next. It keeps the original quirk where playback speed also moves pitch, then adds a Flex option to break that link, DAW sync so the rhythms stay in time, and chord detection that fires the accompaniment buttons from the notes you play.
It runs as a Standalone app plus VST3, AU and AAX on macOS and Windows, and it is Apple Silicon native. A spring-reverb emulation, computer-keyboard control and full MIDI round it out. Set against vintage-flavour instruments such as M-Tron, Arcade and the free Spitfire LABS, Optigan wins when you specifically want that warbly, slightly broken optical-organ sound. The full write-up is in our Optigan feature.