http://articles.latimes.com/2011/dec/02/business/la-fi-sound-cannon-20111202
Now, the power of loud noise is being harnessed by police departments.
A device known as the sound cannon is joining Tasers, rubber bullets and pepper spray in law enforcement's expanding arsenal of nonlethal weapons.
It's officially called the Long Range Acoustical Device, or LRAD, and it has two primary uses. One is as a high-tech megaphone that generates a beam of sound that can cut through the din of a noisy protest far better than conventional public-address systems.
It also functions as a tactical weapon — projecting a high-pitch chirping sound that makes people cover their ears and run away. And with a maximum volume of 149 decibels, the LRAD can get about as loud as a jetliner on takeoff.
Pittsburgh police used LRADs mounted on an armored vehicle to break up demonstrations jamming the city's downtown during the G20 international economic conference in 2009. More recently, New York police officers used small, hand-held LRADs to bark orders as they ousted the Occupy Wall Street protest from Zuccotti Park.
The Los Angeles Police Department has an undisclosed number of LRADs, but they are larger devices fixed to vehicles, which they say might have been helpful in breaking up the Occupy Los Angeles encampment at City Hall this week. Police did not have hand-held units.
LAPD Cmdr. Bob Green said orders to disperse made with bullhorns went largely unheard because of the din of crowd chants and helicopters hovering overhead. The police had to use pickup trucks with massive speakers to get the orders across.
Now, the power of loud noise is being harnessed by police departments.
A device known as the sound cannon is joining Tasers, rubber bullets and pepper spray in law enforcement's expanding arsenal of nonlethal weapons.
It's officially called the Long Range Acoustical Device, or LRAD, and it has two primary uses. One is as a high-tech megaphone that generates a beam of sound that can cut through the din of a noisy protest far better than conventional public-address systems.
It also functions as a tactical weapon — projecting a high-pitch chirping sound that makes people cover their ears and run away. And with a maximum volume of 149 decibels, the LRAD can get about as loud as a jetliner on takeoff.
Pittsburgh police used LRADs mounted on an armored vehicle to break up demonstrations jamming the city's downtown during the G20 international economic conference in 2009. More recently, New York police officers used small, hand-held LRADs to bark orders as they ousted the Occupy Wall Street protest from Zuccotti Park.
The Los Angeles Police Department has an undisclosed number of LRADs, but they are larger devices fixed to vehicles, which they say might have been helpful in breaking up the Occupy Los Angeles encampment at City Hall this week. Police did not have hand-held units.
LAPD Cmdr. Bob Green said orders to disperse made with bullhorns went largely unheard because of the din of crowd chants and helicopters hovering overhead. The police had to use pickup trucks with massive speakers to get the orders across.
