[Petronski]

Thanks for the ping.

Can anyone help me out on the science on this: I seem to recall a crowd-control device that involved super-low frequencies...something about a certain sub-20hz frequency that induced in the human nervous system (through the spinal column IIRC) a palpable sense of panic and fear.

I either saw a fascinating documentary on the topic, or I am hallucinating badly and need to be sedated. You decide. ;O)

[Petronski]

I think you will like this story.

[MD_Willington_1976]

Human body resonates around 7Hz apparently...with enough power at that frequency you could make someone fall apart...

Fun stuff...

[steplock]

This is the same techology, albeit a bit louder, as the directed audio advertising they now have in many stores.

You stand in front of a display or product and ONLY you can hear the sales pitch that is focused only on you.

What you were thinking of is the device - now hidden from public knowledge - that was published back around 1985-1990 or thereabouts in Popular Science or Science & Experiments magazine for a burglar alarm / Deterent that was low-freq sound based.

The closer a burglar or anyone came to the source, the worse they felt - the problem was, it was easy to figure that if you increased the amplitude of the waves, you greatly increased the effects.

Get too close to the amplified versions and you could have a boiled brain...or at least a bit scrambled.

It was supposed to only deter crime

[Eala]

Don't know about your devices (though I seem to recall something about optical devices around 13 Hz being disruptive), but I can tell you from personal experience that continuous very high-volume sound has the potential to bring on unconsciousness in a few seconds (I didn't actually lose consciousness during my ~6 seconds of exposure but I don't think I was far from it).

[WestTexasWend]

"...something about a certain sub-20hz frequency that induced in the human nervous system (through the spinal column IIRC) a palpable sense of panic and fear."


Sounds like some of the symptoms Europeans are claiming to suffer from the "woosh" of wind farms. (They're wooshies.....sorry)

The LRAD is good thinking, though, and might help in tracking "persons of interest" ... who soon will be:
1) hard-of-hearing and easier to sneak up on, or
2) wearing ear protectors.

[grimalkin]

I could have sworn I saw an article posted here about that. The idea came from great cats... I recall tigers specifically. They make very low frequency sounds when confronting prey. It is said to stun them.

[eno_]

I've long wanted to have such a device mounted on my car so that the next time I'm stopped for revenue purposes I can make the cop soil his trousers before he reaches my car. Then I'll fiegn not being able to find my registration for a minute or two while it slides down his pants leg.

[Wumpus Hunter]

There was a South Park where Yoko Ono put together a world wide festival, and the boys amplified Kenny G or someone playing "The Brown Note". Everyone crapped their pants.

I guess you had to see it to appreciate it.