Yeah I can hear some CRT's and amps and things like that - the iphone app doesn't mimic electric whining noises - it goes to much higher frequencies, well above what anyone would use for a normal ringtone.

 

I can hear the ultrasonic mouse deturrent thingy's. They give me a headach. I have lost some hearing in other frequencies. I built car subs for 10 years.

 

Another overall test for audio ranges that we were playing with at my office

http://www.phys.unsw.edu.au/jw/hearing.html

 

I can hear as high of a frequency as a bat can.

 

I like how you all are treating this 2006 article as new news , I think I saw this on the news back 3 years ago.

 

'Cause you're sooooo cutting edge

 

are they for real?

 

Ya this is an old topic, I remember people first started doing it when i was in highschool 4-5 years ago. Really interesting idea though, there is an app for the iphone that lets you test the frequency you can hear up to.

People used to call it "The Mosquito ringer"

 

Couldn't they all just use the vibrate setting on their phone for in class messaging?

 

Once I get home i can get my good headphones out