LRAD is basically a focused beam of sound. Originally, it was designed to emit a very loud sound. Anyone whose head was touched by this beam, heard a painfully loud sound. Anyone standing next to them heard nothing. But those hit by the beam promptly fled, or fell to the ground in pain.
Our technicians also figured out a way to use it to communicate:
LRAD can also broadcast speech for up to 300 meters. The navy planned to use LRAD to warn ships to get out of the way. This was needed in places like the crowded coastal waters of the northern Persian Gulf, where the navy patrols. Many small fishing and cargo boats ply these waters, and it's often hard to get the attention of the crews. With LRAD, you just aim it at a member of the crew, and have an interpreter "speak" to the sailor.
And in Iraq, our troops have figured a way to mess with our enemies:
It appears that some of the troops in Iraq are using "spoken" (as opposed to "screeching") LRAD to mess with enemy fighters. Islamic terrorists tend to be superstitious and, of course, very religious. LRAD can put the "word of God" into their heads. If God, in the form of a voice that only you can hear, tells you to surrender, or run away, what are you gonna do?
This is hilarious. How about a little voice telling one terrorist that the guy next to him is really an infidel and must be killed immediately?