Abstract: Improved low frequency electro-acoustic transducer apparatus of the type employing two piezoelectrically driven flexure discs mounted at the ends of a short cylindrical housing containing an acoustic mismatch fluid, is provided. The piezoelectrically driven flexure discs are constructed as assemblies having a plurality of concentric piezoelectric laminar sandwich units to excite the flexure discs. By individually electrically exciting the concentric sandwich structures through band-pass filters and a selective interconnection network, the flexure discs function with a plurality of resonant frequencies of flexing to provide broad band and efficient operation.