Air-raid sirens, Frank Sinatra songs and Muhammad Ali trash talk blared over the Southern California desert in a demonstration of new acoustic technology for crowd control and disaster communications.

In mid-90’s morning heat at Edwards Air Force Base, HPV Technologies and American Technology demonstrated prototypes of non-lethal sonic devices for a group of military and law enforcement guests, including representatives of the U.K. Home Office.



Representatives of both companies say that within days, they will ship some units of their respective products to areas hit by Hurricane Katrina, so authorities can use the tools for crowd control, aid distribution and rescue operations.



Costa Mesa, California-based HPV showed off three sizes of its Magnetic Acoustic Device, or MAD, a black square panel composed of multiple speakers. The units on display ranged from about 4 to 10 feet across.



The device uses magnets approximately 6 inches tall and 9.25 inches wide to convert electrical pulses into sound waves, and is capable of aiming sound precisely for thousands of feet — like the sonic equivalent of a laser, or spotlight.



Its path and reach can be affected by environmental factors such as nearby flat surfaces, hills, bodies of water or strong bursts of wind.



A series of test sounds beamed out by MAD, including gunfire, music and instructional commands, were audible and intelligible at distances of up to a mile.



When a subject is at close range in MAD’s sonic path, and it is set to high volume, the sound can be excruciating.



The ability to broadcast instructions or alerts at great distances with minimal distortion could be useful for authorities and rescue crews in areas where other communications systems are unavailable.



American Technology is donating four devices — three MRADs (medium-range acoustic devices) and one LRAD (long-range acoustic device). The four devices will be shipped out Friday to a Marine military police unit that is deploying to the Gulf States area for disaster-relief efforts.



“We are donating the use of one of our most powerful prototypes, LTPMS-2, for use in Mississippi as soon as possible, because the governor of that state said that the biggest problem they have right now is the fact that they have no communications infrastructure to get information or instructions out to people,” he said. “They can very easily put this on a truck and send sound out for a minimum of at least a mile in either direction.”



The Los Angeles Sheriff’s Department, which hosted the event as a guest of the Air Force base, is considering using MAD to replace conventional public address systems and as a non-lethal “area denial option” — a way to clear crowds in civil unrest without using chemical agents, rubber bullets or the like.



“You don’t appreciate how powerful this stuff is until you stand a mile away and can’t see the transmitter — but can hear every word in a Queen song,” said Cmdr. Sid Heal, who heads the Los Angeles Sheriff’s Department technology exploration program. “At a quarter mile, it sounds as clear as a car radio; at a half a mile, you have to raise your voice to talk to the guy next to you; at three quarters of a mile, laborers raking up leaves were putting in music requests.”



By Xeni Jardin



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