Patent ID: 6195440
Filing Date: 2001-02-27
Classification: H04R

Abstract:
A signal reproducing device comprising(a) a transducer system for imparting motion to a sound radiating diaphragm having a certain mechanical impedance comprising:a piezoelectric element subject to displacement by applied electric potential and having a top side, an under side and an outer perimeter;a substrate for imparting motion from said piezoelectric element to a sound radiating diaphragm, said substrate having an upper and lower side, with the upper side of the substrate being joined to the underside of the piezoelectric element, said substrate having a larger surface area than the piezoelectric element and having substantially the same rigidity as the piezoelectric element but a greater rigidity than a diaphragm to which the lower side of the substrate will be attached, herein the transducer system has a mechanical impedance that is matched to the echanical impedance of the sound radiating diaphragm; andb) a signal input device used to drive the transducer.