Thanks, Jason!
The pirate repellent/crowd control device works on a very different principle. As I understand it, the device uses a carrier wave of about 200 KHz, although I know of no reason it couldn't be higher. The "noise" is superimposed on this carrier wave, which can be much more directional than the normal 20 Hz - 15 KHz range of human hearing. The noise more or less "falls out" of the carrier wave when the wave hits something, like your head, or your attack boat. Earplugs and headphones do not work. And the decibels can be cranked up to "deafen them permanently and render them unconscious levels".
There is a second device that gives people in its field an intense burning feeling without actually burning them. I've seen it mounted on a Humvee and its pretty big (for the Humvee). Descriptions from test subjects say it is impossible to stay in its field. I believe the agony that either device can cause has led to uncertainty about the legality of their use under international law--they could be considered torture devices.
We normally associate high levels of noise with large speakers and lots of power. Hence, N scale is not really a player for earth-shaking bass. This technique seems to partially contradict those associations. While it is not accurate, I would call it laser noise.
I believe it might be possible to use the first technique to achieve very realistic sound on any scale layout, at much lower power levels. But it might be very expensive.
Yeah, it's weird. But who would ever believe most of our high-definition images of earth are produced by synthetic aperture radars (SARs), not optical cameras. That's Google's secret, btw.