An inventor in Wales has created a sonic annoyance weapon that targets teenagers (mostly).

The device, called the Mosquito (“It’s small and annoying,” Stapleton said), emits a high-frequency pulsing sound that, he said, can be heard by most people younger than 20 and almost no one older than 30. The sound is designed to so irritate young people that after several minutes, they cannot stand it and go away.

So far, the Mosquito has been road-tested in only one place, at the entrance to the Spar convenience store in this town in South Wales. Like birds perched on telephone wires, surly teenagers used to plant themselves on the railings just outside the door, smoking, drinking, shouting rude words at customers and making regular disruptive forays inside.

“On the low end of the scale, it would be intimidating for customers,” said Robert Gough, who, with his parents, owns the store. “On the high end, they’d be in the shop fighting, stealing and assaulting the staff.”

Gough (pronounced GUFF) planned to install a sound system that would blast classical music into the parking lot, another method known to horrify hang-out youths into dispersing, but never got around to it. But last month, Stapleton gave him a Mosquito for a free trial. The results were almost instantaneous. It was as if someone had used anti-teenager spray around the entrance, the way you might spray your sofas to keep pets off. Where disaffected youths used to congregate, now there is no one.

I wonder if I’d still be able to hear something like this?  While I have some notches in lower frequency ranges (due to gunfire and drums), my high frequency ranges used to be quite sensitive.  I don’t doubt that I’ve lost some as I’ve gotten older, but I often still hear things that others don’t (then again, maybe it’s just me   ).

I recall that we used to have trouble with a dog that would chase cars.  In an attempt to deter her we bought one of those sonic devices that only dogs are supposed to hear.  It had two tones, each one with a button.  One tone would be a warning and the other for stopping the bad behavior.  It never really did work on the dog, but I know that if I was close enough to it I could hear the tones, which were nerve-jarring enough to make you slightly nauseous.  I learned this because my sister snuck up behind me one day and hit the button to see what would happen (I think she may have been surprised when I reacted to the sound…).

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