Ever played with HSS "Hypersound" speaker?

[wbeaty]

Has anyone here had a chance to mess around with those weird ultrasound loudspeakers? "HSS" or "Hypersonic." Still priced a bit steep for just being a weird toy.

But then how much would you pay for the ability to make mysterious voices appear inside someone's head?



I keep seeing the things on various sites, sometimes below $200, but I won't be tempted unless I can find a used one for way less.

Am I missing out? Are they far cooler than I suspect?

Here's a guy who tried building his own: http://zao.jp/radio/parametric/index_e.php
I suspect that it sounds like crap unless you have the secret preprocessing algorithm to cancel out the nonlinearities.

[Pano]

Your last sentence is key. It's not easy to do.

[CLS]

Makes me think of these:
Digital Sound Projector - Home Theater Systems - Audio & Visual - Products - Yamaha United States

[wbeaty]

Originally Posted by Pano

Your last sentence is key. It's not easy to do.

But perhaps it's not hard to beam electronic greeting-card music into distant brains? Set up hoaxes where the CIA harasses people with mind-control rays transmitting video game music from 1979?

A hobbyist DIY LRAD weapon.



The closeups of the HSS devices look like aluminized mylar ESLs. They give 50KHz as operating freq (quarter inch wavelength, no?) From their description the basic signal appears to be something like a double sideband DSB modulation, where air nonlinearity causes freq pairs to mix back down to audible.

But also they say that it only starts working above a certain sound pressure threshold.

LRAD Corporation

USA Today


PS
I've always wondered what would happen if I connected a desktop Tesla coil to a simple basic ESL. A half kilowatt at 200KHz. Probably destroy my own hearing by accident. Perhaps char distant surfaces or set fire to sound-absorbing objects. Hmmmm! BOWL-SHAPED ESL! Oooooo. Don't stick your finger in the focus. I've also heard that at certain high (ultra)sound pressure levels, the pressure excursions become so large that you can see little silver mirages appearing at the standing wave antinodes...

[Andersonix]

Bill,
Can we assume you enjoy listening at home to ESLs of your own design?