Patent ID: 8072843
Filing Date: 2011-12-06
Classification: H04R

Abstract:
1. An electro-mechanical transduction apparatus comprising: a first electrically active transduction driver section having moving ends and which supports acoustic waves; a tail section coupled to one end of the first electrically active transduction driver section; a second electrically active transduction driver section having moving ends and which also supports acoustic waves; a load coupled to one end of the second electrically active transduction driver section; means for acoustically inter-coupling the first and second electrically active transduction driver sections; and a source for exciting said transduction driver sections to cause the excitation of at least two multiple resonant frequencies including, at least one symmetrically driven odd numbered mode and one anti-symmetrically driven even numbered mode, with constructive positive addition and enhancement thereof between the multiple resonant frequencies and reduced cancellation below the lowest resonant frequency, providing enhanced output below and in the vicinity of the fundamental resonance and an extended wideband null free response from below the first resonance to at least above the second resonance.