The ‘Beauchamp Synthesiser’ or ‘Harmonic Tone Generator’ James Beauchamp, USA, 1964

Beauchamp Synthesiser or Harmonic Tone Generator at the Experimental Music Studio at the University of Illinois at Urbana-Champaign. USA

Beauchamp Synthesiser or Harmonic Tone Generator at the Experimental Music Studio at the University of Illinois at Urbana-Champaign. USA

James Beauchamp invented the Harmonic Tone Generator in 1964, one of the first additive electronic voltage-controlled synthesisers, under the direction of Lejaren Hiller at the Experimental Music Studio at the University of Illinois at Urbana-Champaign.

“The instrument synthesised six exact harmonics with variable fundamental frequency from 0 to 2000 Hz. The amplitudes of the six harmonics, the fundamental frequency, and the phase of the second harmonic were programmed by voltage control. The fundamental frequency (pitch) was controlled by an external keyboard or generators to provide vibrato and other effects. Control of amplitude was provided by special envelope generators or external generators or even by microphone or prerecorded sounds.

The harmonics were derived by generating pairs of ultrasonic frequencies which were nonlinearly mixed to produce audio difference frequencies. That is to say, one set of frequencies, 50 KHz, 100 KHz, …, 300 KHz, was fixed. Another set, 50-52 KHz, 100-104 KHz, …, 300-312 KHz, was variable. When 50 and 50-52 KHz, etc., was mixed, the sine tones 0-2 KHz, … was derived. Harmonics were generated by full-wave rectification (even harmonics) and square wave chopping (odd harmonics), followed by band pass filtering to separate the harmonics.

The envelope generators consisted of variable delays and attack/decay circuits. In response to a trigger signal from the keyboard, after a programmed delay, the envelope generator would either rise and then go into an immediate decay while the key is depressed or it would rise and decay after the key is depressed. Having the upper harmonics delayed with respect to the lower ones gave an interesting effect.

Because the amplitude controls were “bipolar” (i.e., either positive or negative controls were effective), the instrument could serve as a multi-frequency “ring modulator”, which was especially useful when the controls were derived from a voice or musical instrument. The frequency control was also bipolar and was capable of producing rich sound spectra when the control was taken from a sine generator operating at frequencies ranging from 20 Hz through several hundred Hz. This FM effect was very popular for producing sounds useful in electronic music compositions.”

James Beauchamp.

James Beauchamp working on the  Harmo

James Beauchamp working on the Harmonic Tone Generator c1964

Several electronic music compositions utilised the Harmonic Tone Generator as their main source of electronic sounds. Among them are:

Herbert Brun, “Futility, 1964″

Lejaren Hiller, “Machine Music” and “A Triptych for Hieronymus”

Salvatore Martirano, “Underworld”

Kenneth Gaburo, “Antiphonics III”, “Lemon Drops”, “Hydrogen Jukebox”, and “For Harry”


Hiller, Lejaren, and James Beauchamps, .Research in Music with Electronics., Science, New Series, Vol. 150, No. 3693 (Oct. 8, 1965): 161-169.


The ‘PIPER’ System James Gabura & Gustav Ciamaga, Canada, 1965

Charles Hamm, Lejaren Hiller, Salvatore Martirano, Herbert Braid, Kenneth  Gaburo at the EMS, Toronto, 1965

Charles Hamm, Lejaren Hiller, Salvatore Martirano, Herbert Braid, James Gaburo at the EMS, Toronto, 1965

PIPER was one of the earliest hybrid performance system allowing composers and musicians to write and edit music in real time using computers and analogue synthesisers. The system was developed by  James Gabura & Gustav Ciamaga Who also collaborated with Hugh Le Caine on the ‘Sonde’) at the University of Toronto (UTEMS) in 1965. With computing technology in 1965 being to weak to synthesise and control sounds in real-time a work-around was to leave the scoring and parameter control to the computer and the audio generation to an external analogue synthesiser. The PIPER system consisted two Moog oscillators and a custom built amplitude regulator to generate the sound and an IBM 6120 to store parameter input and to score the music. The computer would read and store the musicians input; keyboard notes, filter changes, note duration and so-on and allow the user to play this back and edit in real-time.

By the 1980′s such large hybrid analogue-digital performance systems like PIPER and Max Mathew’s GROOVE were obsolete due to the advent of affordable, microcomputers and analogue/digital sequencer technology.



Robb Wave Organ. Morse Robb. Canada. 1927


The Robb Wave Organ designed by Morse Robb in Belleville, Ontario was said to be  musically superior to the Hammond Organ. The instrument attempted to reproduce the sound of a cathedral pipe organ by amplifying sounds generated by a similar tone-wheel mechanism. Prototype models were created in 1927 and the production model came on the market in 1936 and remained available until 1941.


A newspaper article on  the organ-printed almost ten years before it became available-was headlined: “Young Canadian Invents Pipeless Ethereal Organ” (Toronto Star, 1927). The Robb Wave Organ was more expensive than other electronic organs, and sales suffered because of the Depression and World War II. With only thirteen units sold, the company ceased operation in 1941. The Museum has preserved prototype and final tone wheels and drums from Mr Robb’s workshop.

Michael J. Murphy professor RTA School of Media talks about the Robb Wave Organ



Canada Science and Technology Museum

The ‘Composer-tron’ Osmond Kendall. Canada, 1953

The Composer-tron

The Composer-tron

Developed during the early 1950′s by Osmond Kendall for the Canadian Marconi Company, the Composer-Tron was an analogue synthesis and composition instrument that utilised an innovative and unique control system. The Composer-Tron had a cathode ray tube input device that could ‘read’ patterns or shapes hand drawn on it’s surface with a grease pencil. The drawn shape could be defined as the timbre of the note or as the envelope shape of the sound, rhythmical sequences could be written by marking a cue sheet type strip of film.

The purpose of the Composer-Tron, like that of the ‘Hanert Electrical Orchestra‘, was to provide a synthesis and composition tool that closed the gap between composer and performer allowing the composer to define all the aspects of the music in one session:

“At present, the composer writes his mental symphonies as black symbols on white paper. He has no way of knowing wether they’re just what he had in mind. Months or years may pass before he hears them played by a symphony orchestra. Not uncommonly he never hears his best work……with Kendal’s grease pencil, the composer can, in effect, draw the grooves in the record. Working with a Composert-Tron….he can walk out of his study with his recorded composition under his arm.”


“The Art Of Electronic Music”, Darter,Tom. 1984 GPI Productions.