‘Dr Kent’s Electronic Music Box’, Dr Earle Kent, USA, 1951

Dr Earle Kent's Music Box
Earle Kent and his ‘Music Box’ circa 1951

The Electronic Music Box was a synthesis and composition device designed and built as a personal project by Dr Earle.L.Kent while employed at the C.G.Conn Ltd Company, USA, to design electric organ circuits.1Margaret Downie Banks, Dynamic Research: Earle L. Kent and Conn’s Research Department, National Music Museum,The University of South Dakota. The Music Box was an analogue ‘beat frequency’ vacuum tube based synthesiser controlled by a punched paper strip device as used previously in the 1930’s by instruments such as Coupleaux’s Givelet and later, the RCA mkII and Siemens Synthesiser amongst others. The punch paper strip was a system similar to a ‘pianola’ paper reader and allowed the composer to produce musical sequences that were beyond the manual dexterity of the performer:

“The goals established for the music Box involved wider flexibility of performance than is possible in any conventional musical instrument. It was felt that it should not be confined to the usual limitations of manual keying. It should be capable of grater speed and wider combinations than are possible by manual or pedal dexterity, and it should not be limited to the equally tempered scales as are most keyed instruments. It was recognised that virtually any speed or combination could be obtained by keying with a perforated paper roll with the loss of some of the vital control usually exercised by a musician while making music and also with the loss of its conventional acceptance as a musical instrument. However, it was felt that a musician usually “records” his manual manipulation rather precisely in his brain before a concert by repetitive rehearsal and that the losses by recording this operation on paper would be exceeded by the gains”
Dr Earle.L.Kent
Dr Earle Kent
Dr Earle Kent at the C.G.Conn Ltd CompanyLabs c 1950

Although based on the established ‘beat frequency’/heterodyning principle, Kent’s instrument employed a more complex system of frequency changers to create a more interesting range of timbre and control over the shape of the note. The Music Box was designed to allow control off the ‘slurring’ of the note, formant filtering control and control of volume and depth and rate of tremolo. The Electronic Music Box was influential on the development of electronic musical instruments, Dr Kent was visited by Harry Olson who later adapted features of his RCA synthesiser to incorporate functions of the Music Box, but the Conn company chose not to exploit the commercial possibilities of the instrument.

Percy Grainger (L) and Earle Kent (R) with and ‘Dr Kent’s Electronic Music Box’ at Kent’s Research Engineering Department for the Conn Company, Elkhart, USA. image: Grainger Museum Archive, 99.6700.1

The Australian ‘Free Music’ composer Percy Grainger contacted Earle Kent shortly after Kent had completed his PhD at the University of Michigan. Grainger was looking for an instrument that would be suitable for his concept of free music:

“Play any pitch of any size, half, quarter or eighth tones, within the range of 7 voices, to be able to pass from pitch to pitch by way of a controlled glide as well as by leap, to play precisely controlled, complex irregular rhythms past the scope of human execution.”

Grainger visited Kent’s research department at the Conn Musical Instrument Company in Ekhart USA in 1951 to witness the Electronic Music Box which shared many features of Grainger’s somewhat crude constructions. However for undisclosed reasons, Grainger was unsatisfied with the Music Box and returned to his own Free Music experiments in Australia.2Grainger Museum Archive. https://omeka.cloud.unimelb.edu.au/grainger/


  • 1
    Margaret Downie Banks, Dynamic Research: Earle L. Kent and Conn’s Research Department, National Music Museum,The University of South Dakota.
  • 2
    Grainger Museum Archive. https://omeka.cloud.unimelb.edu.au/grainger/


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