Phason is an audio object using rotating, perforated discs to create cyclical triggers (sequencer). The controlling agent in this piece is the light which is passing from the console panel through fibre-optic light guides. Passing through the perforation, light hits the photo sensors, triggering the synthesizer.
The object may be used as an instrument or an autonomous sound installation. To interact with it, one may use a built-in flashlight on a flexible holder, or any other small light sources (for example, a phone flashlight).
The idea of the object is predicated to a large extent on Soviet experiments with optical sound, and also the automatic music boxes and caskets at the turn of the 19th-20th centuries, when disks were frequently used to encode sound and rhythms.