The Polyphone is a performance-oriented musical instrument designed by Canadian physicist Hugh Le Caine and built in the National Research Council of Canada’s (NRC) Electronic Music (ELMUS) Lab in Ottawa, Canada. It is the world’s first known keyboard-based electronic synthesizer that allowed for multiple notes to be played at once. Its name, Polyphone, is derived from this polyphonic capacity. It permitted musicians, for the first time, to play a synthesizer as they would a piano or organ: with two-hand accompaniment and multi-note chords.

The Special Purpose Tape Recorder (or Multi-track) was the first studio-oriented instrument designed by Canadian physicist Hugh Le Caine and built in the National Research Council of Canada’s (NRC) Electronic Music (ELMUS) Lab in Ottawa, Canada. It was created to afford composers the opportunity to alter and recombine pre-recorded sounds into a single musical output. This prototype version of the instrument used a three-octave keyboard to control the speeds of six tapes simultaneously, and then mix them down into a single recording.

The Electronic Sackbut, designed by Canadian physicist Hugh Le Caine, is the world’s first known voltage-controlled synthesizer. It employed various techniques in electronic signal processing – among them the generating, dividing, filtering, modulating, and blending of electronically-produced waveforms – to permit new ways of creating and controlling musical sound.