Somehow, I came across this group and after reading I thought I'd respond. I really like the idea of this device. It could really come in handy, especially if used on other humans. For several years, someone has been using such a device towards myself. With FM modulation, it is possible to project voice within this ultrasonic blast. I've heard it first hand, yeah you don't really hear thru your hearing, it's more like originating from the walls around you, sorta like feeling it, but can make out what is being said. I've pissed off someone nearby and they are harassing me on almost a 24/7 basis.