Here we have a rare vintage Yamaha DX7 Optical Volume Expression Pedal. This accessory is designed for use with electronic keyboards and allows for dynamic control of the volume and expression of the sound. Although untested, this pedal is a sought-after item for musicians and collectors of Yamaha equipment. Its unique design and potential functionality make it a valuable addition to any music studio or collection. Pedal is unmarked brand wise so have base my listing on info found on net. See last 2 pics
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