The Ondes Martenot is one of the most expressive and influential early electronic instruments, with a fascinating history. It was invented by Maurice Martenot, a French cellist and radio operator, and patented in 1928. Martenot wanted to create an electronic instrument with the expressivity of a cello but the timbral range of radio oscillators.
Like the Theremin, it uses heterodyne oscillators to produce sound. It is controlled by a keyboard (with lateral movement for vibrato) and a sliding ring on a wire (called the ruban) to create gliding pitches. Expression key (touche d’intensité): responds to pressure, shaping dynamics like a bowed string instrument. Its timbre is smoother and warmer than the Theremin, more suitable for lyrical and orchestral use.
Olivier Messiaen (Turangalîla-Symphonie, 1948), Darius Milhaud, André Jolivet, and others wrote extensively for it. It was used in French cinema and Hollywood (e.g., Maurice Jarre’s Lawrence of Arabia, 1962, and recent films by Radiohead’s Jonny Greenwood), and is still played by specialists such as Jeanne Loriod, who championed the instrument in the 20th century.
It is known for its haunting, expressive sound, somewhere between a human voice and string instrument.
It anticipated later synthesizers by combining pitch control, dynamic control, and timbral shaping. The Ondes Martenot was never mass-produced in large numbers, but it remains a beloved instrument among composers who value its unique voice.