... beam at range to 250 meter , and max noise level to 150dB . The LRAD drive device also named High Power Directed ... of Operate:Long Range Acoustic Device work principle like Antenna array, arrange multi acoustic unit which can generate high power acoustic on ... @134dB(rms) CompositionAcoustic base array ,Signal Source, Amplifier, Controller, Power Supply Long Range Acoustic Device For Pirate Defense