Switch mechanism of piano with built-in electronic musical instrument

A piano with an electronic musical instrument built therein comprising:

• a plurality of hammering mechanisms for striking a plurality of strings in response to operation of a keyboard;
• at least one pedal for controlling string striking sound produced by said hammering mechanisms,
• an electronic musical instrument provided with an electronic sound source controlled according to the operation of said keyboard;
• an inhibition means for inhibiting said hammering mechanisms from producing the string striking sound during the performance of said electronic musical instrument;
• a changeover switch for changing between the performance mode of said electronic musical instrument and the performance mode of said hammering mechanisms, in response to one of a plurality of operations of said at least one pedal;
• a movement condition detection means for detecting the movement of said at least one pedal when the performance mode of said electronic musical instrument is set by said changeover switch;
• and
• at least one electronic sound adjustment means for adjusting the electronic sound produced by said electronic musical instrument corresponding to the movement of said at least one pedal detected by said movement condition detection means.