SPWC

The short version:
"A tone outside the audible range of hearing for most people over the age of 30. This means that you can get phone calls and receive text messages in class or school without teachers hearing it..."

Store owners are also considering using these (maybe some have already started?) as a deterrent so younger people don't loiter outside their establishments since only they can hear the higher frequencies.

Test yourself here: http://www.freemosquitoringtones.org/

Anyone heard of these? What's the highest frequency you can hear?

i remember reading an article about these about two years ago and they never really became popular. i was able to hear down to 16khz

I was able to hear 20khz. I remember hearing about these a couple years ago.

I can hear up to 18khz. I heard about them a while back but there are debates going on now as to whether or not they want to implement them where I live. I picture myself running away from stores

17.4khz

.....I blame too many concerts and constant iPod use =x

I'm surprised I could hear up to 22, but then again I'm 18 but then again I have the worst hearing EVER.

I found this test very strange. I could hear just barely the 16 one, but could hear really well the 15. Geez I feel old! What I find interesting is I am kind of known for hearing things that most people don't. Maybe not dog frequency things but noises and far away stuff. This was an odd test! Makes me think I'm losing my hearing. Perhaps a few too many concerts!

That's pretty interesting. I can hear up to the 22khz. I was surprised!

it reminded me of those wierd hearing tests in elementary school

I can barely hear the 18khz. That makes me feel old.

very cool Kemmy -- I will plead the 5th on what I can hear

okay, now I really don't buy this "test". I tried it at home and got one result, tried it at work and got something completely different. Like you basically can only hear the top one at my desk computer.... Stupid test!

tones? what tones?