Saturday, February 16, 2008

The Mosquito and High Frequency Hearing and Ringtones

Wiki
The Mosquito or Mosquito alarm is an electronic device which emits loud high-frequency tones (approximately 17.4 kHz at 85dB). Because the ability to hear high frequencies deteriorates in humans with age (a phenomenon known as presbycusis), the noise is mostly commonly audible to animals, babies, younger children and teenagers.

The device is marketed for use as a sonic weapon for preventing teenagers from remaining in the vicinity of the device. It is very popular in the UK, with some 3500 in use, mostly by shopkeepers and police authorities. It is currently legal for private citizens to use, even in public areas.
This device has also been installed in The Netherlands in a couple of places to prevent youths from gathering. How the hell is something like this possible in our free country? What about children who want to play outside?

On this ringtone site you can test your hearing of high frequency sounds (if your speakers can produce them). I hear all the way up to the 22kHz range.

Why a ringtone site?
NPR
The war between teens and authority figures has a new — or old — front: ears. British shopkeepers tired of teenage loiterers have turned to the Mosquito teen repellent, which emits a high-pitch frequency that most teenagers can hear — but not most adults.

But now teens have struck back against the Mosquito: They are using the same sound to communicate without adults' knowledge.

At issue is a text-message ringtone that emits the same pitch as the Mosquito. Using it, students can learn about a new message while they're in class — where they're not supposed to be using their cellphones. Most of their teachers can't hear the alert.

Inventor Howard Stapleton, creator of the Mosquito teen repellent, says only a few people over age 30 can hear the Mosquito's sound. He and his 16-year-old daughter Isabel talk to Melissa Block about the sound, which has been dubbed "Teen Buzz."

5 comments:

Douchebag said...

It's weird I can't hear the 16khz tone. But I can hear 17 and 17.4 and all the way up to 19 khz. But when I hit the twenties, instead of a monotone tone......I hear a flutter of the same tone.

Kamiel said...

maybe the sperm i sneaky putted in youre ears when you where sleeping. got something to do with that douchebag.

its the first time i tryed to digg so hope it worked.

cybrbeast said...

it worked, very good.
Douche before the sample starts you hear a slight sound anomaly, after that the tone starts.

annom said...

Its a fun device to play with, but weird that they actually use it to prevent public youth gatherings etc. Ridiculous!

I can't hear tones above 19kHz. Not sure if my speakers can actually produce the tones.

Anonymous said...

i could hear all of them but for 20,21, and 22 i had to listen very clostly