Some basic glossary terms snatched from this.

Acoustic Beam . High power, very low frequency beam emitted from weaponry under development. Envisioned to be a piston-driven or detonation-driven pulser which forces compressed air into tubes to generate a low frequency wave [543,546].

Acoustic, Blast Wave, Projector. Energy generation from a pulsed laser that will project a hot, high pressure plasma in the air in front of a target. It creates a blast wave with variable but controlled effects on hardware and troops [543].

Acoustic Bullets . High power, very low frequency waves emitted from one to two meter antenna dishes. Results in blunt object trauma from waves generated in front of the target. Effects range from discomfort to death. A Russian device that can propel a 10-hertz sonic bullet the size of a baseball hundreds of yards is thought to exist. Proposed fixed site defense [16,113,212,543]. Also known as sonic bullets.

Acoustic, Curdler Unit . A device which is plugged into an HPS-1 sound system to produce a shrill shrieking, blatting noise. It is used to irritate and disperse rioters and had a decibel range just below that of the danger level to the human ear. It is used in night operations to produce a “voodoo” effect and effectively breaks up chanting, singing and clapping [2:279- 280,82:184,84,529].

Acoustic, Deference Tones . Devices which can project a voice or other sound to a particular location. The resulting sound can only be heard at that location [176:86].

Acoustic, Doppler Effect Alarm . Any movement in the area between a transmitter and a receiver causes a slight variation in the sound pattern received. By measuring this variation an alarm system can be made to be activated [23:204].

Acoustic, High Intensity Sound . Loud music was used by American forces to drive Manual Norriega from the Vatican Embassy in Panama in 1990. Also known as polysound [354:45].

Acoustic, HPS-1 Sound System . A 350 watt sound system with an audible voice range of 2 1/2 miles. Used by the military in Indo-China and then supplied to law enforcement. First used by police forces at San Francisco State College and at Berkeley in the 1960s [2:277-279,82,84]. See also Acoustic, Curdler Unit.

Acoustic, Infrasound . Very low- frequency sound which can travel long distances and easily penetrate most buildings and vehicles. Transmission of long wavelength sound creates biophysical effects; nausea, loss of bowels, disorientation, vomiting, potential internal organ damage or death may occur. Superior to ultrasound because it is “in band” meaning that its does not lose its properties when it changes mediums such as from air to tissue. By 1972 an infrasound generator had been built in France which generated waves at 7 hertz. When activated it made the people in range sick for hours [23,302,546].

Acoustic, Squawk Box . Crowd dispersal weapon field tested by the British Army in Ireland in 1973. This directional device emits two ultrasonic frequencies which when mixed in the human ear become intolerable. It produces giddiness, nausea or fainting. The beam is so small that is can be directed at specific individuals in a riot situation [451,452,504].

Acoustic, Teleshot . Cartridge projecting a powerful sonic device delivered by a 12-gauge shotgun. Experimental use in 1972 [529].

Acoustic, Ultrasound. A very high frequency sound whose wavelength is “out of band” making it less effective than infrasound because it losses its properties when it changes mediums. Example, from air to human tissue. Like infrasound a lot of power is required to generate these waves which create biophysical effects. See also Acoustic, Infrasound.