Keyboard musical instrument allowing player to perform ensemble together with electronic sound system

A keyboard musical instrument comprising:

• an acoustic keyboard instrument including
• a keyboard having a plurality of keys assigned notes of a scale and respectively rotated when forces are exerted thereon,
• a plurality of key action mechanisms respectively connected to said plurality of keys so as to transfer said forces therethrough,
• a plurality of hammer assemblies respectively associated with said plurality of key action mechanisms, and driven for rotation by said plurality of key action mechanisms transferring said forces thereto, and
• a plurality of vibrative means respectively struck by said plurality of hammer assemblies driven by said plurality of key action mechanisms for generating acoustic sounds having said notes;
• and
• an electric system including
• a plurality of actuators respectively provided for said plurality of keys and responsive to driving signals for exerting said forces on said plurality of keys,
• an electronic sound generating means responsive to music data codes for generating electronic sounds, and
• a controlling means responsive to an instruction supplied from the outside of said keyboard musical instrument so as to selectively enter into an electronic sound mode and an acoustic sound mode, said controlling means supplying said music data codes to said electronic sound generating means in said electronic sound mode, said controlling means generating said driving signals from said music data codes so as to supply said driving signals to said plurality of actuators.