Abstract: A fluid pulsed generator system including an elongated tubular member of uniform elastic parameters constructed for receiving fluid flow therein and abruptly terminating said flow to create an acoustic pulse containing most of its acoustic energy in the zero to 160 Hertz frequency spectrum. The system generates a directionally distinctive acoustic pulse. The system includes a fluid reservoir adapted for supplying a suitably high fluid pressure for driving a fluid through the elongated tubular member with sufficient velocity to generate an acoustic pulse basically of the classical water hammer variety The device is provided in a marine configuration comprising an elongated acoustic radiating conduit containing the water hammer generated pressure pulse adapted for trailing from a vessel beneath the surface of a body of water.