Ghost of a flea: The rest is silence

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December 20, 2008

The rest is silence

Lest anyone doubt the inventiveness of the young, I bring news to set your mind at ease. Or, if you are in a teaching profession, to fill you with an incalculable dread/rage/foreboding. I have only just got used to the idea my lectures will be second guessed live by the top ten Google search results (which is pretty cool, if I'm honest).

Now this latest horror: The Mosquito Tone.

Now for those of you who don't follow pop culture and web trends, et. al, a "mosquito tone" is simply a 17KHz sine wave that geeky youngsters have been known to use on their cell phone to alert them when they've got a text message so the teachers can't hear it. See, studies say that most of us old folks (I'm over 30 now) can't hear much above the 13-14KHz range.

Plastic Mind hosts sample tones for the more sceptical Flea-readership. I can just hear 16KHz... do remember to turn down your speakers...

Posted by Ghost of a flea at December 20, 2008 11:23 AM

Comments

Yeah, I'm 30 and cannot hear the 17 khz. The 16 I can hear if I crank my headphones to full blast, but couldn't hear it on medium sound.

Stupid test anyways! :-0

Posted by: Temujin at December 20, 2008 01:36 PM

Fascinating. 17 and 18 are out-of-band for me. Others come in 5x5.

Posted by: Chris Taylor at December 20, 2008 02:34 PM

I played one of those tones without warning my officemates, one of which was 24 at the time. I heard absolutely nothing (at mid-30s) and wasn't even sure I'd actually played the file. Then, from behind me, the 24-year-old:

"What's that high-pitched noise?"

Posted by: JohnAnnArbor at December 20, 2008 07:38 PM

I read about this a few months ago. I told one of the older guys at work about it and we hooked up an old HP signal generator to a set of speakers and tried it out. Sure enough I heard it and he didn't. I'm close to 40 and he's in his mid 50's. I heard the 18 kHz as well.

Posted by: dpatten at December 20, 2008 09:25 PM

The potential offensive uses of this phenomenon had not occurred to me until now... heh...

Posted by: Ghost of a flea at December 21, 2008 01:01 AM

I'm a decrepit 48 and everything is audible _except_ the 16 kHz.

Posted by: Nicholas at December 22, 2008 12:08 PM