Patent ID: 7732691

Claim:
A keyboard percussion instrument comprising: at least one tone bar disposed over at least one resonator tube having a first opening; a tube cover which is configured to cover at least a portion of the first opening, the cover being moveable between a first position and a second position in which a greater or lesser portion of the first opening is covered than when the tube cover is in the first position, and a plurality of positions between the first and the second positions; and an actuator mechanism adapted to allow a user to manually control movement of the tube cover through intermediate positions between the first position and the second position such that changes in position of the tube cover correspond in real-time to changes in position of a body part of the user actuating the actuator mechanism, wherein, in the first position, the tube cover is laterally offset from an axis of the resonator tube such that the first opening is completely exposed to the tone bar and, in the second position, the tube cover is interposed between the tone bar and the resonator tube such that the tube cover covers at least a portion of the first opening.