Abstract: This invention relates to musical instruments, more particularly the invention has reference to stringed instruments, primarily the amplified guitar. The main object of this invention is to provide an instrument of the character described, which will permit a musician to play bass and guitar simultaneously, by operation of an upright lever device. It is a object of the invention in this regard to so design the instrument, so that while both hands are occupied, either by strumming or plucking while chording, he is able to pull the lever with his arm to achieve a tone as described in the instructions of operation of the arm operated musical string tensing device, hereinafter referred to as the Pace Bace.