I heard this story on the NPR Story of the Day podcast a couple of weeks back and then a friend sent me an article from the NYTimes yesterday.
The gist is, in the UK, “inventor Howard Stapleton” discovered that teenagers can hear frequencies that many adults can’t and so he decided to turn those frequencies against them. Dubbed the “Mosquito teen repellent,” the frequency would be emitted at irregular intervals and would prove to be really irritating to teenagers and they would leave the premises.
The twist, however, is that teenagers have turned this invention on it’s head and are using it to send text messages undetected in class to one another. Most teachers can’t hear the tone and the virtual note passing is successful.
I thought I was done with the story until I ran across this while surfing tonight. Blogger Ochen K has the original mosquito sample as well as a series of test frequencies for your listening (ear shattering) pleasure.
For me it stops hurting at around 20,000Hz, whereas my wife is fitting in perfectly with our over-30 demographic.
What frequencies can you hear?