| 摘要 |
An automatic player piano in which solenoid-operated key actuator units are provided respectively in association with the individual keyboard keys and are energized normally with signals effective to produce sounds with dynamic levels within a predetermined, selectable operable range of the player piano, wherein when it is desired that the player piano be used as a background music player, the key actuator units are energized with signals effective to produce sounds with dynamic levels within another range at least partially lower than the predetermined operable range of the player piano. |
