A 24 mm cell of water, under coloured lamps. Rings of needles at the rim play notes into it; the water answers with standing waves, and every lamp lights the slopes that tilt toward it. Play two flutes a hair apart and watch the pattern breathe with the beat.
Flute, clarinet and cello are measured from the University of Iowa Musical Instrument Samples.
Strobes are simulated, never flashed. A photosensitivity limiter keeps any large area from flickering faster than three times a second.