A keyboard musical instrument is equipped with solenoid-operated key actuators for guiding a player in fingering on the keyboard, and the solenoid-operated key actuators stop the keys at terminative positions on the way to the end positions, wherein key sensors supplies detecting signal representative of the keys reaching the terminative positions to a controller so that the controller removes the driving signals from the solenoid-operated key actuators immediately before the escape of jacks from the hammers.
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