Sound made visible. Three journeys, every station an instrument you can play.

Foundations: what sound is and how we hear it, for anyone starting out: frequency and level, phase, timbre, the ear, and on through digital audio, levels, rooms, dynamics, microphones, space and meters.

Ratio: eight stations on interval, resonance and the ear, from the Lissajous figure to the vibrating plate. Every figure is computed from the tones actually sounding.

Synthesis: nine stations on timbre, the subtractive voice, envelopes and LFOs, FM, wavetable, additive, granular, physical modeling and processing. Play them from the screen, the computer keyboard, or a MIDI controller.

Headphones help.

Sound starts when you press begin. Arrow keys move between stations. In Synthesis, Z to M and Q to P play notes, minus and equals shift the octave.