The Le Caine Instruments
A Disappearing technology
The Le Caine instruments: an excellent source for a listing of all Le Caine instruments is the well researched book by Gayle Young, The Sackbut Blues (published in 1989 by the Museum of Science and Technology, Ottawa).
A complete listing is given on page 167 of the above mentioned book. The machines relevant to the nature of today’s presentation are:
- Oscillator Bank (OB) (1957-59), the unit at our EMS (built in 1961) consisted of 24 wave generators (sine, square, pulse and sawtooth waves) controlled by a touch sensitive keyboard. Since each key could control one generator (or group of generators) the instrument had the potential of producing 24-note chords. Le Caine’s initial OB had 16 generators (1957). However, two years later he created a machine with 108 generators (controllable also by the Spectrogram – see below).
- Tone Mixture Generator (TMG): this very special unit consisted of 13 sine tone generators, each equipped with pitch and amplitude controls. It produced sine clusters of extreme complexity, and had a voltage-controlled system able to transpose the structure as a whole above or below its two octave range, providing esoteric glissandi at the same time.
- Filter Bank (FB): octave filters, six of them on a panel, designated as A, B, C, etc. These filters could be used in series or in parallel. They were all identical and covered the same range, but the type and parameters for the desired filtering situation could be set for each one. Each had eight adjustable band-pass filters. In all, they covered eight octaves and had a total of forty-eight level controls. The individual or multiple outputs could then go to the Serial Structured Sound Generator (SSSG), or the Multi-Track Tape Recorder (MTTR) for further treatment.
- Voltage Controlled Filter (VCF): built in 1957 (an improved version was produced in 1962) had a HI-Pass, LO-Pass filter, controllable by voltage. More advanced versions of these filters became part of the Polyphone (Poly).
- Multi-Track Tape Recorder (MTTR) was also known as “Special Purpose Tape Recorder for Montreal”. The initial machine (1957) had six stereo tape recorder heads. Since a tape loop or a complete reel of tape could be ‘read’ by each head, the user could control a mix of 12 different recorded sound sources. The unit at McGill had ten stereo heads, hence a potential for 20 different channels of recorded information. A keyboard controller was attached to the unit,but solely for speed variation control. The unit could be set at 7 1/2 ips or 15 ips, with the range for speed variation one octave below or above the set speed. The MTTR had a built in mixer, and also stereo spring reverb of a very high quality. It was the six head machine that LeCaine used for the creation of his well known piece, “Dripsody” (1955).
- Serial Sound Structure Generator (SSSG): Based on the ‘serial switch’ concept used in early automatic telephone switchboards. Separate modules stored sequences applied to four musical aspects of sound events: duration, pitch, envelope and timbre. All sequences were stored and coordinated by ‘timers’. 1[1. (Le Caine developed his ‘timers’ years before our present hardware or software based sequencers were invented)] The timers moved the series from one term to the next, forward or backwards. At the same time, a series of time values was stored in the duration module. The 13 selector switches with 12 positions then would sequence the steps through pitch, envelope and timbre modules. An additional switch provided a choice of a set of 12 ‘tempi’, controlling the overall duration of the sequence. External controls: there was the possibility of by-passing the timer and using external sources like random pulse generators or control tapes to achieve more sophisticated effects. This sophisticated unit could also play the sequences in reverse mode, inversion and retrograde inversion. The number of terms or steps programmed for each module – from 4 to 13 – could be assigned individually. The result was that the sequences would loop, but not in a synchronized number of steps if so programmed, so each pitch value was heard with a different envelope and/or duration for each cycle until the ‘overall’ (multi)sequence returned to the original position.
Voltage control could be applied to pitch, to harmonic content (i.e. controlling a wave rich in harmonics, say a square wave), or to the production of glides from one pitch to the next. The SSSG could interact with other Le Caine units, like the TMG, the VCF and also the Multi-Track. All operations of the SSSG were based on variable voltage control. Le Caine wrote “One is tempted to describe it in the vocabulary of computer science. In a sense, it might be described as a small computer or apparatus which employs elementary logic circuits to carry out serial compositions”. (Le Caine, Science and Music, 1967. Quoted in The Sackbut Blues, p. 215).
- Polyphone: this unit was developed by Le Caine at the suggestion of Paul Pedersen, to become part of the McGill EMS. The prototype – and only unit built – was delivered to the EMS in 1970. It was always referred to as ‘the Poly’ (it is unclear if this was ‘Pauli’ – from Paul Pedersen, or ‘Poly’ from Polyphonic). In essence, it was a polyphonic analogue synthesizer, utilizing voltage controllable sources and procedures, and operated by a keyboard with touch-sensitive keys. In addition there were a half-dozen foot pedals, actually pressure-sensitive foot pedals operating photocell switches. These graduated light-sensitive controls introduced changes in ‘amplitude’, ‘modulations’, ‘filterings’, or ‘pre-sets’. As far as anyone can tell, the Poly was the first analogue, voltage controlled, polyphonic synthesizer in the world, pre-dating the Moog and Buchla by almost a decade.
Each of the 36 keys (in a 37 keys keyboard, one being a ‘zero’ setting, a reference control) had its own oscillators with waveform controls, so both pitch and timbre could be adjusted separately for each key. Each oscillator was able to cover the complete audio range. Additionally, on the upper panel, there were five tunable low-frequency generators, mostly used as signals or controls to the keyed oscillators. The synthesizer was completed with separate envelope generators with manual controls for attack and decays, and four independently adjustable filters covering the whole range.
All functions of the Poly were voltage controlled.
Conclusion: the contribution of Dr. Le Caine to the establishment of McGill’s first EMS is very important. When the first McGill EMS opened in 1964 (directed by Istvan Anhalt), the studio was integrated almost entirely by Le Caine’s inventions: the Multi-Track (with ten stereo heads), Spectrogram, Oscillator Bank (24 oscillators), Filter Bank (six filters), the SSSG with 3 of the 13 stages timers. Additionally Le Caine prepared for the EMS a modified Ampex tape recorder (with speeds of 15, 7 1/2, 3 3/4 and 1 7/8 i.p.s, all switchable speeds); Envelope Generators, Ring Modulators and Speed Control devices for tape recorders. At the McGill EMS, the so called ‘Main Studio’ was, as ideated by Le Caine, “a splice-less electronic music studio”.
In the 1980’s, at the initiative of the Hugh Le Caine Project, an effort was made to bring together all surviving Le Caine creations under one roof: the Museum of Science and Technology in Ottawa. In September 1987, the McGill EMS donated all the Le Caine units housed at McGill to that Museum’s collection. Today, the Le Caine machines are kept in the Museum’s warehouse, and can be seen by the public only on special request. On occasion, although, some of the units are re-exhibited as part of the regular Museum displays. Also, for particular shows, some of the units have been exhibited again in Montreal.
- aMEGdotario: articles, analysis, essays by alcides lanza (personal folder in his computer)
- Gayle Young: The Sackbut Blues (Museum of Science and Technology, 1867 St. Laurent Boul., Ottawa) phone: 613 991 2983.
- Musicworks: Issue #83, Summer 2002, pages 42-51)
- Electronic Music Festival, the EMS 25 anniversary (December 7&8, 1990) (McGill University, EMS souvenir program)
- Hugh LeCaine (compact disc): Compositions/Demonstrations 1946-19174 (JWD Music – 146 Ridge Rd West, Grimsby, ON L3M 4E7 – Canada email@example.com
- Also: www.hughlecaine.com