The Scalatron was an unusual microtonal electronic instrument developed in the early 1970s by Motorola as a new venture into the instrument market. Promoted as the ‘first instant-performance instrument that plays in the cracks’ the Scalatron was aimed squarely at a more experimental, microtonal market – if such a market existed. The instrument itself was a rather basic synthesiser consisting of 240 square wave oscillators (one for each key) built into a wooden home-organ casing.
The instrument was controlled in early models by a dual manual and later using a multi-coloured ‘Bosanquet generalized keyboard’ designed by the Chicago microtonal composer George Secor. The Secor keyboard consisted of 240 tuneable oval multicolored keys and allowed the user to create complex tunings
“Earlier that year (1974) I had attended a demonstration of the Scalatron (digitally retunable electronic organ) prototype, and recognizing that conventional keyboards were not the best way to perform music with more than 12 tones in the octave, I unwittingly proceeded to re-invent the Bosanquet generalized keyboard and subsequently approached the Motorola Scalatron company with the proposal of employing it on their instrument.”… “Around that time several members of the xenharmonic movement had gotten in touch with Scalatron president Richard Harasek and sent him copies of the first two issues of Xenharmonikôn, which he passed on to me and which I promptly read. The second issue included Erv Wilson’s diagrams of a modification of Bosanquet’s keyboard, with hexagonal keys, at which point it became clear that my keyboard proposal was not new… For the remainder of the year I was heavily involved in the generalized (Bosanquet) keyboard Scalatron project and, after that, in using it to explore new tunings. In effect, the keyboard that I had discovered was destined to be overshadowed by the one that I had rediscovered.”
Costing around $6000-$10,000, the Scalatron was an expensive and unusual instrument. Less than 20 Scalatrons were ever made (including only 2 Secor versions). The Scalatron came with a black and white monitor to adjust each key’s pitch (using Motorola’s TV tuning technology) – a split screen showed horizontal bars representing true pitch on the left side and the instruments variable pitch on the right side, and, for an additional $1000 a cassette interface was added with a number of tuning ‘programmes’. George Secor toured with the instrument playing works by Harry Partch (who also used the instrument towards the end of his life) and Ben Johnston. The Scalatron is still much in favour – though very hard to find – by microtonal composers and was used on several albums by Jon Hassell, most notably ‘Vernal Equinox’.
“Finally they invented what I needed–forty years too late.”
Harry Partch via Kenneth Gaburo