Building An Optigan-like Instrument

[Olli] sent in his writeup of a musical instrument he made called the Black Deck. [Olli]’s instrument was inspired [Jimi Tenor]’s photophone – a transparent disk attached to a fan and photocell.

A transparent disk is placed on the turntable [Olli] rescued during a dumpster diving expedition. A light shines though the optical disk and is picked up by phototransistors. After writing a program to generate an A minor scale onto a transparency, [Olli] connected his contraption to a stereo and heard his creation speak. To control the individual tracks (or notes) on the disk, [Olli] made a keyboard out of photoelectric switches that control which note is played.

Superficially, [Olli]’s instrument resembles an Optigan. While [Olli]’s instrument is capable of producing waveforms, the Optigan is able to reproduce sampled instruments. That being said, we think [Olli]’s Black Deck would feel comfortable next to the Optigans of Kraftwerk and Devo. Check out the YouTube demo of the Black Deck in action after the break:

Continue reading “Building An Optigan-like Instrument”

Resurrecting The Optigan Disc Format


The Optigan and Orchestron were a pair of electronic organs built by Mattel in the 1970s which used swappable optical discs to store instrument information. The discs can still be found today, but the organs are extremely scarce, much to [Gan’s] dismay. After researching the organs for a bit, he decided he could probably build his own MIDI-compatible interface for the audio discs.

The discs have audio waveform data printed on them, which can be read using an LED on one side of the disc and an optical transistor on another. After successfully prototyping a reader that could interpret one of the disc’s audio tracks, he constructed a device to read all of the tracks simultaneously, just like the original organs.

His makeshift turntable was constructed on top of an old record player using acrylic discs and toy car wheels to keep things steady. Once the disc is placed on the turntable, he sets his reader in place, and via some custom circuitry, he is able to play the discs using his much more modern keyboard. It sounds pretty decent as you can see in the video below, though he does admit he would like to tweak a few things to make it sound even better.

[thanks Bryan]

Continue reading “Resurrecting The Optigan Disc Format”