12 stepper motors rotate panes of glass. The vibrations of the motor resonate in the glass, which acts as a mechanical amplifier, producing a ringing tone. The pitch of varies with motor speed and can be precisely controlled.

Skylight mounted solar panels feed power to the motors and an MMMSE. The motors sing according to available light. At rest, the silent motors eat light and store energy. Upon full charge, they commence singing. As the stored voltage dies, pitch and volume slowly drop. After several minutes they must stop and rest again.

When starting to sing, the motors gradually glissando up to the particular home note to which they are tuned. Each motor's note is part of a major chord. Because the motors are independent, working according to relaxed parameters, they start and stop at different times. While not random, the overall effect is difficult to predict and varies with sunlight, cloud patterns, time of day and so forth. Richly resonant in changing dissonances and harmonics, a complex drone that never repeats itself is created.