Abstract: The specification discloses a pneumatic player piano which utilizes an electric motor roll drive. The roll drive is actuated by a mechanical switching arrangement which responds to the system vacuum so as to simulate the operation of a conventional air motor. The pneumatic stack is constructed to permit the pouch board and valve boxes of an entire level to be fabricated in a single molding operation. The valves themselves are formed of silicone rubber - and require neither backing, facing nor position adjustment.