The ‘Keyboard Theremin’ Leon Termen, USA, 1930.

Leon Termen's 'Keyboard Theremin' 1932
Leon Termen’s ‘Keyboard Theremin’ 1932


Leon Termen, the creator of one of the first widely used and mass produced electronic instruments the eponymous ‘Theremin’ developed a keyboard version of the instrument during his stay in New York. The Keyboard Theremin used the same heterodyning technique to generate a monophonic tone but this time controlled by a five octave 61 key manual instead of the Theremin’s difficult to master hand gestures. The ex-cellist Termen also added a fingerboard continuous controller so that the player could switch between keyboard and string like playing. The instrument had two foot pedal to shape the sound and add vibrato and a series of organ-like stops to emulate the timbres of conventional instruments such as the organ, Piano, brass, woddwind as well as percussive timpani effects. The amplified output of 100 watts was fed into a bank of six twelve inch speakers.(1)

The 'Theremin Electric Symphony Orchestra' c1932. The Keyboard Theremin is on the right with a Theremin Harmonium on the left and several Theremin Cellos in the centre.
The ‘Theremin Electric Symphony Orchestra’ c1932. The Keyboard Theremin is on the right with a Theremin Harmonium on the left and several Theremin Cellos in the centre.

The Theremin Keyboard was premiered at a concert at the Carnegie Hall in 1932 by the ‘Theremin Electrical Symphony Orchestra’; a ten player ensemble (Termen originally wanted forty musicians) all playing fingerboard and keyboard theremins, each instrument tuned to take the part of an orchestral instrument and performing a ‘conventional’ classical repertoire including J.S.Bach’s ‘Fantasia in G’ and ‘Ave Maria’. Impressed by it’s range and portability, the composer Leopold Stokowski used the Keyboard Theremin at orchestral concerts in Philadelphia, New York and Washington.

'The Theremin Electro Ensemble' later called 'The Electrio' in 1932. (Left)Playing the RCA theremin is Leon Theremin's assistant, Julius Goldberg (with customised "lightning bolt" art deco, brass nickel chrome antennas). (Centre) playing the "Theremin Cello" is the Leonid Bolotine and (Right) Pianist Gleb Yellin is playing a Theremin Keyboard. In 1932, the ensemble could be heard on the radio every Monday afternoon at 2:15 over the Columbia Network, KMBC. (2)
‘The Theremin Electro Ensemble’ later called ‘The Electrio’ in 1932. (Left)Playing the RCA theremin is Leon Theremin’s assistant, Julius Goldberg (with customised “lightning bolt” art deco, brass nickel chrome antennas). (Centre) playing the “Theremin Cello” is the Leonid Bolotine and (Right) Pianist Gleb Yellin is playing a Theremin Keyboard. In 1932, the ensemble could be heard on the radio every Monday afternoon at 2:15 over the Columbia Network, KMBC. (2)


(1)’ Theremin: Ether Music and Espionage’ By Albert Glinsky. p145


‘Music From Electrons’ Radio News. August 1972 P76. Irving J. Saxl. Phd


















Theremin Orchestra, Carnegie Hall. C1930
Theremin Orchestra, Carnegie Hall. C1930


Images of the Theremin

Promotional brochure for the RCA Theremin


Biographical Information: Leon Sergeivitch Termen. 1896 – 1993


Lev Termen and Theremin virtuoso Clara Rockmore
Lev Termen and Theremin virtuoso Clara Rockmore




Termen's American born second wife, the dancer Lavinia Willaims
Termen’s American born second wife, the dancer Lavinia Willaims



Leon Termen interview By Olivia Mattis and Robert Moog 1992








The ‘Rhythmicon’ Henry Cowell & Leon Termen. USA, 1930

Henry Cowell and the Rhythmicon
Henry Cowell and the Rhythmicon

In 1916 the American Avant-Garde composer Henry Cowell was working with ideas of controlling cross rhythms and tonal sequences with a keyboard, he wrote several quartet type pieces that used combinations of rhythms and overtones that were not possible to play apart from using some kind of mechanical control- “un-performable by any known human agency and I thought of them as purely fanciful”.(Henry Cowell) In 1930 Cowell introduced his idea to Leon Termen, the inventor of the Theremin, and commissioned him to build him a machine capable of transforming harmonic data into rhythmic data and vice versa.

“My part in its invention was to invent the idea that such a rhythmic instrument was a necessity to further rhythmic development, which has reached a limit more or less, in performance by hand, an needed the application of mechanical aid. The which the instrument was to accomplish and what rhythms it should do and the pitch it should have and the relation between the pitch and rhythms are my ideas. I also conceived that the principle of broken up light playing on a photo-electric cell would be the best means of making it practical. With this idea I went to Theremin who did the rest – he invented the method by which the light would be cut, did the electrical calculations and built the instrument.”

Henry Cowell

“The rhythmic control possible in playing and imparting exactitudes in cross rhythms are bewildering to contemplate and the potentialities of the instrument should be multifarious… Mr. Cowell used his rythmicon to accompany a set of violin movements which he had written for the occasion…. The accompaniment was a strange complexity of rhythmical interweavings and cross currents of a cunning and precision as never before fell on the ears of man and the sound pattern was as uncanny as the motion… The write believes that the pure genius of Henry Cowell has put forward a principle which will strongly influence the face of all future music.”
Homer Henly, May 20, 1932

The eventual machine was christened the “Rythmicon” or “Polyrhythmophone” and was the first electronic rhythm machine. The 17 key polyphonic keyboard produced a single note repeated in periodic rhythm for as long as it was held down, the rhythmic content being generated from rotating disks interrupting light beams that triggered photo-electric cells. The 17th key of the keyboard added an extra beat in the middle of each bar. The transposable keyboard was tuned to an unusual pitch based on the rhythmic speed of the sequences and the basic pitch and tempo could be adjusted by means of levers.Cowell wrote two works for the Rythmicon “Rythmicana” and “Music for Violin and Rythmicon” (a computer simulation of this work was reproduced in 1972). Cowell lost interest in the machine, transferring his interest to ethnic music and the machine was mothballed.

Rhythmicon Discs
Rhythmicon Discs
After Cowell, the machines were used for psychological research and one example (non working) of the machine survives at the Smithsonian Institute. The Rhythmicon was re-discoverd twenty-five years after its creation by the producer Joe Meek (creator of the innovative hit single ‘Telstar’, 1961) apparently discovered abandoned in a New York pawnbrokers. Meek brought it back to his home studio in London where it was used on several recordings. This Rhythmicon was used to provide music and sound effects for various movies in the Fifties and Sixties, including: ‘The Rains of Ranchipur’; ‘Battle Beneath the Earth’; Powell and Pressburgers’ ‘They’re a Weird Mob’; ‘Dr Strangelove’, and the sixties animated TV series ‘Torchy, The Battery Boy’.The Rhythmicon was also rumoured to have been used on several sixties and seventies records, including: ‘Atom Heart Mother’ by Pink Floyd; ‘The Crazy World of Arthur Brown’ by Arthur Brown, and ‘Robot’ by the Tornadoes. Tangerine Dream also used some sequences from the Rhythmicon on their album ‘Rubicon’.
Rhythmicon Discs
Rhythmicon Discs


“Henry Cowell: A record of his activities” Compiled June 1934 by Olive Thompson Cowell.

The ‘Terpsitone’ Leon Termen, USA & Russia,1932

Termen's Terpsitone 1936
Termen’s Terpsitone 1936











