The Mosquito Tone

[boston bean]

The Mosquito or Mosquito alarm (marketed as the Beethoven in France, the Swiss-Mosquito in Switzerland and SonicScreen in the US and Canada) is an electronic device, used to deter loitering by young people, which emits a sound with a very high frequency. The newest version of the device, launched late in 2008, has two frequency settings, one of approximately 17.4 kHz[1] that can generally be heard only by young people, and another at 8 kHz that can be heard by most people. The maximum potential output sound pressure level is stated by the manufacturer to be 108 decibels (dB).[2] The sound can typically only be heard by people below 25 years of age, as the ability to hear high frequencies deteriorates in humans with age (a phenomenon known as presbycusis).

The device is marketed as a safety and security tool for preventing youths from congregating in specific areas. As such, it is promoted to reduce anti-social behaviour such as loitering, graffiti, vandalism, drug use, drug distribution, and violence. In the UK, over 3,000 have been sold, mainly for use outside shops and near transport hubs.[3] The device is also sold in Australia, France, Denmark, Italy, Spain, Germany, Switzerland, Canada and the USA.[4]

The Mosquito has attracted controversy on the basis of human rights. Critics say that it discriminates against young people and infringes their human rights, while supporters argue that making the Mosquito illegal would infringe the human rights of shopkeepers who suffer business losses when "unruly teenagers" drive away their customers.[5] Mosquito distributors have said that they keep standards to ensure that the device is not abused, and Howard Stapleton who invented the device has asked European governments to legislate guidelines governing its use.[4]

http://en.wikipedia.org/wiki/The_Mosquito

I had never heard of this before, no pun intended.....

Here is a link to test if you can hear the mosquito tone. Be careful when listening and follow the directions at the link, by making sure your speakers are not turned up all the way.

http://journal.plasticmind.com/ears/mosquito-tone-or-how-to-tell-youre-a-youngun/

[Warpy]

1. OK, that's weird

I could hear 11kHz, 14kHz, and 18kHz but none of the others. I'm OLD, too.

My ears have always tested out much better than my age would suggest and I can always hear the tone when a CRT warms up.

As long as the mosquito is singing at one of the frequencies I can't hear (tinnitus probably interferes), I'll be fine.

[Confusious]

6. Could be your speakers

A lot of cheap speakers don't do higher ranges very well.

Even cheaper might not be able to handle certain frequencies.

I got sick of it myself, so I built my own.

[Warpy]

10. I've got AR speakers hooked to this box

and they're certainly not bad ones. I did hear the 18K.

[canoeist52]

7. With ya on the tinitus. Couldnt hear 12 or 16

wonder if they're the same frequency as the high hissing in my head.

[psychmommy]

2. I could not hear any of them.

Dang I am an old timer.

[Indpndnt]

3. I could hear the first two easily and then up to 16, but only if I cranked up my speakers.

That's when one of the dogs left the room. And I couldn't hear 17 or 18, at all.

Well over 30 here, btw.

[Confusious]

8. Could be your speakers

Cheap sets don't do higher ranges very well.

After about 3 or 4 times of spending $50 to $100 a pop I got sick of it and built my own.

[Indpndnt]

9. Laptop speakers, so, no surprise there!

[Confusious]

4. 43, I could hear them all

I think he has them backwards though,

The 18khz was a lot deeper then the 11khz, and the 11khz was a lot more annoying.

Ps. I also have a kick ass pair of speakers which I built myself, so that might have something to do with it.

Maybe I wouldn't hear them depending on amplitude?

[Quantess]

5. Interesting.

[DainBramaged]

11. I may be old and deaf in one ear but I heard 15K perfectly

[HiPointDem]

12. over 55, i could faintly hear the higher frequencies but the lower ones not at all. i hope it's my

speakers.

and if i play two at the same time, i hear them all -- very loudly.

weird.