Axehole

Interesting article about the use of sound as a weapon:

It is possible to produce extremely strong infrasound and ultrasound at volumes high enough to cause damage, but, Altmann argued, producing the sounds alone is not enough to create an actual sonic weapon. The main difficulty lies in propagating the sound waves over distance to their intended target, a possibility hampered by the tendency of low-frequency waves to expand in all directions, thus losing focused power, and of high-frequency waves to enter a “shocked state” where energy is lost to the air.

So sonic weapons, even those employing ultrasound and infrasound, would only work over very short distances and, rather than resulting in the kinds of psychological or physical effects claimed by conspiracy-heads or military nuts, would probably just cause serious and permanent
hearing damage. Altmann had found no evidence that human targets would be rendered incapable of action by being severely spooked or losing physical control: “I have found no hard evidence for vomiting or uncontrolled defecation, even at levels of 170 dB or more.”