The Rocksichord is an electronic keyboard invented in the 1960s to approximate the sound of the harpsichord. As its name suggests, it was primarily used in rock music (in the 1960s and 1970s and notably by 1990s band Quasi), but it has also been used in jazz (by Call Cobbs, Jr. and Sun Ra) and contemporary classical music (in the work of Terry Riley).
The Rock-Si-Chord, as it was named by its manufacturer Rocky Mount Instruments (RMI), a division of Allen Organs Inc, was a solid-state instrument using one or two transistor oscillators per key, and was the first example of a type of instrument generally known as the electronic piano (contrast electric piano). Later RMI instruments also included piano sounds (via Wikipedia).
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