Electric harpsichord

The clavecin électrique (or clavessin électrique) was a musical instrument invented in 1759 by Jean-Baptiste Thillaie Delaborde, a French Jesuit priest. It is the earliest surviving electric-powered musical instrument, pre-dated only by the Denis d'or, which is only known from written accounts.

Delaborde described the instrument in his 1761 publication, Le clavessin électrique. The mechanism was based on a contemporary warning-bell device, and the instrument is essentially an electric carillon. A number of bells, two for each pitch, hang from iron bars along with their clappers (one for each pair). A globe generator charges the prime conductor and the iron bars. The musician presses a key and one of the bells of the corresponding pair is grounded, cut off from the charge source. The clapper then oscillates between the grounded and the charged bells, producing the desired tone.

The somewhat inappropriate choice of the instrument's name was defended by Delaborde, who claimed that it was far superior to a carillon. He also mentioned that during a performance in a dark room the listener's "eyes are agreeably surprised by the brilliant sparks" that were produced by the instrument. The press and the public admired the innovative machine, but it wasn't developed further. The model Delaborde himself built survives and is kept at the Bibliothèque nationale de France in Paris.

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