The high-performance piezoelectric underwater speakers developed, patented and manufactured by Lubell Labs of Columbus Ohio. The LL964H continue to set the world record for having the widest frequency response and output level of any commercial underwater speaker made, at a price that is both reasonable and affordable. Because of its rugged die-cast aluminum housing with 150mil PVC overmold, the LL964H may be used in rivers, lakes, and ocean without worry of corrosion. Because of the higher impedance of the LL964H, long cable lengths with minimal insertion loss are possible using standard SO cable. For instance, four LL964H underwater speakers each having a 1.5km long 14/2AWG cable may be connected in parallel (14ohms) to an amplifier rated at 200 watts at 8ohms (40Vrms) resulting in a sound pressure level of 177dB/uPa/m at each transducer.