Piezoelectric audible sound generator

A piezoelectric audible sound generator comprising:

• a self oscillator including a piezoelectric transducer which includes inherent equivalent capacitance between first and second electrodes thereof, amplifier means connected to said first and second electrodes for driving said piezoelectric transducer to oscillate at a predetermined frequency and in a predetermined phase, said amplifier means including inherent bias resistance therein which when combined with said inherent capacitance, produces a phase shift between the driving frequency of said amplifier and the frequency of oscillation of said transducer, and a feedback circuit for transferring a feedback signal from a third electrode of said piezoelectric transducer to said amplifier means, and
• phase compensator means interposed between said third electrode and said feedback circuit for adjusting the phase shift such that said feedback signal from said third electrode is 170.degree.-190.degree. out of phase relative to a signal from said driving electrode.