Created in 1928 by Maurice Martenot, the ondes Martenot was the first practical electric instrument. On principle it works the same as the theremin but in practice, they are quite different, mostly because the ondes Martenot requires physical contact in order to be played. Except for the addition of a keyboard two or three years after its invention, the ondes Martenot design has not been changed in 80 years.
Martenot was a cellist and was keen to create an instrument that could reproduce vibrato. To accommodate this, Martenot created a keyboard that could move enough to allow a vibration of nearly a half tone on either side of the pitch being played. To modern ears, the large glisses and double-wide vibrato bring to mind sci-fi films from the 60s and 70s. In the hands of a skilled player, however, the machine is capable of startling degrees of sensitivity and delicacy. Volume and articulation are controlled with the left hand via glass push button. The further and more forcefully the button is depressed, the louder and sharper the sound.
Olivier Messiaen first wrote for the instrument in 1937 and quickly became one of its biggest proponents. Prominent parts were given to it in Trois petites liturgies de la présence divine (1943&4) as well as Turangalîla-Symphonie. In Turangalîla, Messiaen chose the ondes Martenot as a way to mimic a goddess figure without being restricted by the range and volume of the human voice.
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