COOL :: the Circular Optical Object Locator, by David Merrill and Tim Hankins, is a collaborative music-making device for people who don’t have much musical skills.

The transparent disc can be rotated by hand above an array of six colored lights which represent sounds or instruments. Performers place opaque squares on the table as it spins. The opaque squares obstruct the light shining from below and their position determines the pitch of the note. Hanging above the table is a computer video camera which converts the images into sound.

For example, objects placed near the center might be interpreted as high notes, and as pieces are placed further away from the center the pitch might fall.

Besides, the “mode” of the instrument can be changed by using two control panels made up of three light dimmers, and three mode buttons.
Pressing one of the six mode buttons modifies the key in which the instrument is playing but also the instrument or sound associated with each of the lights. For example, Mode 1 might result in piano and harpsichord and violin sounds being used, whereas Mode 2 might result in electronic and synthesized sounds.

Thanks, Chris.