You could use that to project sound into someone’s head from miles away.
Simply fire two signals of inaudible sound where the difference is the frequency of the sound you want to project.
Two frequencies will not be heard, but the third (the difference) will appear to come out of nowhere... like a psychotic episode.
This has military applications... you can fire a sound that is the threshhold of pain at people and they will not know the origin.
You can also drive someone mad.
Another possible application would be a sonic-scalpel... perhaps also useful in eye-reshaping (think lasik w/o the cutting of the flap) or disruption of gall-/kidney-stones.
This has military applications... you can fire a sound that is the threshhold of pain at people and they will not know the origin.
Baah, we had DI’s at PI that could do that.
That’s why I wear my tinfoil hat, to stop those govm’nt people from tryng to control me with the voices they put into my head.
Reminds me of one of the sonic devices in Heinlein's Sixth Column.
The Pan Asians had taken over the US. The "Good Guys" (former military intelligence type) set up a fake religion, then used the sonic device and other higher tech goodies to get rid of the Bad Guys, who could be selectively disintegrated, leaving the local civilians untouched.
But that device didn't use sound waves, it used a gravitic-electromagnetic force.