A speaker membrane is fitted behind each of the 24 shutters, playing a single sound contribution (mono) by a sound artists. By opening a shutter, the sound behind it becomes louder and thus more distinctive. The volume is regulated by light sensors. At most three shutters (one per vertical row) may be opened at any time. These combination possibilities allow for 728 different sounds/sound mixes. When all shutters are closed, the soft collective sound of the automat can be heard.