iOptigan

What it does

A recreation of the Optigan, an organ released in 1971 by Optigan Corporation, a subsidiary of the toy maker Mattel, which read 12 inch clear plastic optical discs as audio. The left hand triggers backing parts and chords off the spinning disc while the right hand plays a keyboard, as on the hardware. 25 discs come with the purchase and a further 15 are an in-app purchase, each carrying its own keyboard sound plus five switchable backing parts. Discs can spin upside down to play backwards. Settings cover a stereo option against the original mono, radio mode so controls latch, external MIDI, tempo and reverb.

In the demo

Jade plays it from an Arturia KeyStep 37, works through a long run of disc demos from banjo sing along to circus music, moves a chord button through major, minor and diminished, flips a disc to play backwards, and opens it beside Digitalism in AUM.

Worth knowing

It is inter app audio rather than AUv3, and some discs sound rough because the originals had to be tracked down and transferred. Jade points it at lo-fi parts and drones rather than everyday keyboard work.