Bimorphic piezoelectric pickup device for stringed musical instruments

Abstract

A pickup is disclosed for a stringed musical instrument having a plurality of strings. The pickup includes a bridge member having a surface which supports the strings at predefined positions along the surface, a plurality of bimorphic piezoelectric elements embedded in the bridge member at locations corresponding to the predefined positions along the surface of the bridge member, and connection wires for conveying the electric signals generated by said bimorphic piezoelectric element. Each bimorphic piezoelectric element has two oppositely polarized piezoelectric layers, separated by a metallic layer. The bimorphic piezoelectric elements are embedded in the bridge member so that the principal direction of vibrations of the corresponding string is normal to the metallic layer which separates the two piezoelectric layers of the bimorphic element. As a result, the vibrations of each string bend the corresponding bimorphic element imbedded in the bridge, so that the pickup is directly responsive to vibrations of the strings of the musical instrument. In the preferred embodiment, the bridge includes separate support beams, separated by notches or slots, for each string so as to isolate each bimorphic element from the vibrations of the other strings, thereby providing distinct electrical signals corresponding to the vibrations of each string.