
The Occupy movement has become of the longest large-scale protests in US history, and all that protesting had pitted the activists against police departments and their crowd-control weapons. One of the more controversial of those is the LRAD Sound Cannon. So what’s the harm in a little noise? Well, a lot, actually.
The LRAD Sound Cannon is an acoustic weapon and communication device…
Developed by the LRAD corporation to broadcast messages and pain-inducing “deterrent” tones over long distances, LRAD devices come in various iterations that produce varying degrees of sound. They can be mounted to a vehicle or handheld. The device produces a sound that can be directed in a beam up to 30-degree wide, and the military-grade LRAD 2000X can transmit voice commands at up to 162dB up to 9km away.
…that blasts “non-lethal” sound waves…
The LRAD corporation says that anyone within a 100m of the device’s sound path will experience extreme pain. The version generally utilised by police department (the LRAD 500X) is designed to communicate at up to 2000m during ideal conditions. In a typical outdoor environment, the device can be heard for 650m. The 500x is also capable of short bursts of directed sound that cause severe headaches in anyone within a 300m range. Anyone within 15m of the device’s audio path can experience permanent hearing loss. LARD clams the device is not a weapon, but a “directed-sound communication device”.
…and keep birds from hitting planes…
LRAD systems are deployed at airports to sonically deter birds from residing in the paths of aircrafts. The bio-acoustic deterrent helps minimise bird strikes like the one that caused the ditching of Flight 1549 in the Hudson river. In this context, the LRAD broadcasts tones and predator calls that frighten birds away.
…but has also been used against activists…
The LRAD device has been used on several occasions against activists in the US. The first documented use was in Pittsburgh during the G20 summit in 2009. The Pittsburgh police used it again following the Superbowl in 2011. The LRAD has reportedly been used against Occupy protestors in Oakland and recently against Occupy Wall Street protestors in Zuccotti Park.
…and has potentially long-term side effects.
Use of the device has come under fire because of the potential for permanent hearing loss. Human discomfort starts when a sound hits 120dB, well below the LRAD’s threshold. Permanent hearing loss begins at 130dB, and if the device is turned up to 140dB, anyone within its path would not only suffer hearing loss, they could potentially lose their balance and be unable to move out of the path of the audio. The device is also entirely operator dependent, which could lead to serious ramifications if the officer in charge doesn’t have sufficient training.
If you’ve encountered the LRAD Sound Cannon, please drop your experience in the comments below.



















Leonard Low
Friday, November 18, 2011 at 9:24 AMThe LRAD has been used by the Japanese whaling factory Nisshin Maru against several Sea Shepherd whaling protest ships; most notably, the Ady Gil moments before ramming and sinking that vessel. There’s a plethora of video documentation: https://www.google.com/search?client=flock&channel=fds&q=lrad+sea+shepherd&ie=utf-8&oe=utf-8&aq=t
Abe
Friday, November 18, 2011 at 12:14 PMWoah this is crazy!!
dave
Friday, November 18, 2011 at 12:53 PMland of the free…
Maniacal
Friday, November 18, 2011 at 1:03 PMand home of the deaf
Brizeycon
Friday, November 18, 2011 at 5:52 PM+1
DarthDVD
Friday, November 18, 2011 at 2:58 PMok ban it… the police will be sued.
Justin
Sunday, November 20, 2011 at 4:51 PMBet they use Rebecca Blacks songs, or are they classified as lethal?
Matt
Friday, December 23, 2011 at 11:20 AMThe NSW police have been using it to harass, incite fear, disorientate and make the victim seem less credible. As use of transmitted voice over a distance to the victim will mimic many neural disorders.