information:classification, structural:scholar_edition
Invention

Cristofori's great success was designing a stringed keyboard instrument in which the notes are struck by a hammer. The hammer must strike the string but not remain in contact with it, because continued contact would damp the sound and stop the string from vibrating and making sound. This means that after striking the string, the hammer must quickly fall from (or rebound from) the strings. Moreover, the hammer must return to its rest position without bouncing violently (thus preventing notes from being re-played by accidental rebound), and it must return to a position in which it is ready to play again almost immediately after its key is depressed, so the player can repeat the same note rapidly when desired. Cristofori's piano action was a model for the many approaches to piano actions that followed in the next century.