Note: I’ve been informed that if you’re not careful and have your volume up too high, this could damage your speakers. Consider yourself warned!
My friend Karen got me intrigued by a recent blog post in which she describes hearing KFC’s strategically placed “mosquito tone” in one of their recent ads.
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. (See the full chart of who can hear what.)
Of course, when someone says most people can’t do [x], everyone tries it. Sort of like when I read the Snapple cap that said no one can lick their elbow. Now that’s a conversation starter. Anyhow, I fired up Audacity and generated a 17kHz tone, and wouldn’t you know–I couldn’t hear it. So I bumped it down to 14kHz and heard it. At 15kHz, I could hear it so long as I didn’t tilt my head funny. At 16kHz, I could still hear it, but it was really faint. Then I actually decided that I could only hear it if I knew it was playing, but I haven’t been able to test that until I have someone else press play.
My wife just walked in for her middle-of-the-night stroll and screwed her face up funny when I played the 18KHz sound. Show off.
Here are the sounds for you to test yourself with (Ren suggests headphones for best results). They’re all 5-second long .mp3 files:
12 KHz
13 KHz
14 KHz
15 KHz
16 KHz
17 KHz
18 KHz
Done messing with your ears? Check out SymbolAssist a little tool I built for adding characters (like this ✌ and this ♬) to your Twitter and Facebook conversations. (¡ʍʇɟ ‘ʇsıssɐןoqɯʎs)
Or if you’re on Twitter, follow along? I’m usually posting all sorts of interesting things.