Police Use Acoustic Warfare To Disperse Crowds -- Myway/AP
PITTSBURGH (AP) - Police ordered protesters to disperse at the Group of 20 summit last week with a device that can beam earsplitting alarm tones and verbal instructions that the manufacturer likens to a "spotlight of sound," but that legal groups called potentially dangerous.
The device, called a Long Range Acoustic Device, concentrates voice commands and a car alarm-like sound in a 30- or 60-degree cone that can be heard nearly two miles away. It is about two feet square and mounted on a swivel such that one person can point it where it's needed. The volume measures 140-150 decibels three feet away - louder than a jet engine - but dissipates with distance.
Read more ....
More News on the Long Range Acoustic Device
DHS helps local police buy military-style sonic devices -- Washington Times
Sonic Warfare Erupts in Pittsburgh, Honduras -- The Danger Room
Robocops Employ Scary Crowd-Stopping Technology at Pittsburgh Protests -- Alertnet
Sound volume comparisons -- AP