The Ondes Martenot, a monophonic electronic instrument invented in 1928 by Maurice Martenot, has been used by composers including Honegger, Schmitt, Ibert and, perhaps most famously, Messiaen. Honneger even thought it might replace the contrabassoon in an orchestra, saying, ‘The instrument has power, a speed of utterance, which is not to be compared with those gloomy stove-pipes looming up in orchestras.’
The Ondes Marteno is made up of two units: the main section is made up of a keyboard and pull-wire operated by a ribbon controller for the index finger. The keys are capable of slightly shifting, which has the effect of moving the pitch. Sliding the ribbon with the index finger creates glissando sweeps and expressive portamentos.
The left-hand uses the other unit of the instrument, which has controls accessed from a pull-out drawer that adapt articulation, dynamics and tone.
Modern-day fans of the instrument include Radiohead’s Jonny Greenwood, who often tours with an Ondes Martenot, and Daft Punk, who have used the instrument in many of their tracks.
Its mysterious sound has been compared to the human voice, and in some instances it can sound like a soothing string quartet and in others it is eerie and ominous.
Cynthia Millar explaining the nature of the Ondes Martenot, and its role and significance in Messiaen’s Turangalîla Symphony: