"Last week, the L.A. Sheriff's Department tested out an acoustic transmitter that makes earlier models look like "childrens' toys" in comparison. We put the magnetic acoustic device (I'm not sure it has a name yet, so this one will have to do for now) to the test on one of our ranges. Using a variety of sounds from human voice to music to sound effects (screams, shouts, gunfire, sirens, and the like), we succeeded in listening to the sounds from the transmitter located one statue mile in the distance. The edge of the energy path was clearly discernible and you could easily detect when you were standing in it and not, even at one mile. In fact, near the end of the test a wind gusting up to 20 knots blew across our line of sight and we had to adjust for the wind to remain in the energy path."
--Defence Tech via Boing Boing
Mind Control: HyperSonic Sound