Abstract: A percussive action silent electronic keyboard provides electrical input signals for electronic music synthesis equipment. The keyboard includes a housing, and a keyboard array of a plurality of depressable pivoted playing keys adjacently arranged as a musical keyboard. Each key communicates with a pivoted silent hammer in a cam and follower arrangement. A stop is provided for stopping the momentum of each silent hammer which is caused to move about its pivot by following a camming surface of its corresponding key resulting from depressing of the key during playing action. An electrical switch provided for each key, and the switch is responsive to the playing action of the key for generating and supplying electrical signals indicative of the action to the electronic music synthesis equipment with which said keyboard may be used to generate music.

Abstract: In the herein illustrated embodiment the harp or tone generator assembly of the piano is supported pivotally at one end so as to pivot in a substantially horizontal plane on its support, and a mechanism manipulated by the player shifts the movable end of the harp thereby to shift the position of the tone generators in the harp relatively to the percussion hammers, so that while the keys of the piano are depressed for playing, the player can selectively change the tone at will; an amplifying circuit compensates for the loss of volume due to the shifting and to the resultant change of the striking line.