The general arrangement of the instrument (1) is with keys (11) corresponding to the notes of a scale, a number of activating mechanisms (16) connected with the keys for the transmitting the activation force. There are a number of hammer arrangements (18) associated with these mechanisms, rotated by the mechanisms, and a number of vibrating elements (13) struck by the hammers to produce acoustic sounds according to the notes. There is also an electrical system with a number of activating devices (4) for the keys responding to the drive signals.
