Korean Job Discussion Forums

mindmetoo · Joined: 02 Feb 2004

http://www.aubraux.com/mosquito-ringtone.php

I can just barely make out 15Khz. Anything higher, I'm Pete Townshend. Anyway, these tones are used by some merchants to keep kids from hanging out in parking lots. As you get older your ear bones harden and can't make out the higher Khz cycle. So they blast a parking lot with this tone. Teens flee. Adult customers are blissfully unaware.

Now it occurs to me, loop it in your Mp3 player, hook up your mp3 player to your class's PA (or some portable computer speakers on high). Kids don't settle down, blast 'em.

oldfatfarang · Joined: 19 May 2005 Location: On the road to somewhere.

Sounds pretty effective. However, using this method will definately jump up and bite you on the buttttt if you damage a kid's hearing.

I considered using a laser pointer to gain students attention (at tables that weren't listening). But, on reflection, the danger of damaging a kid's eye killed that idea.

Ultimately, a co-teacher that says "ATTENTION!" seems the most effective way of getting students to quiet down and listen (in public school anyway).

waltjocketty · Joined: 09 Oct 2006

How old do you have to be to not hear that? I can hear it and I'm in my late twenties.

kiwiliz · Joined: 20 Apr 2006 Location: New Zealand

Did the test..seems I am very normal...can only hear to 12kHz

Alyallen · Posted: Wed Sep 19, 2007 7:09 pm Post subject:

I can hear up to 17. I can hear 18 but it's really hard, so I think if it was played without my knowledge, I wouldn't notice it...

mrsquirrel · Joined: 13 Dec 2006

Asked the ss what they can hear.

Some of them can hear 18 a couple 19 none 20.

Optimus Prime · Joined: 05 Jul 2007

Sweet! I have the big language lab, just tested it, and immediately, had the 20 kids who play games for the 15 minutes before class clutch their ears and start yelling "Teacher!!!!! What???? Stop!!!!" I of course keep hitting the "PLAY" button.

Thank YOU!!!!!!!!!!!!!!!

iain77 · Joined: 12 Apr 2004 Location: here, now

ha. up to 15khz for me, which is shocking considering the amount of time i spend wearing headphones playing very loud music, and also years in bands. strange.

bassexpander · Joined: 13 Sep 2007 Location: Someplace you'd rather be.

Closin'-in on 40, and I can hear up to 17.

ED209 · Joined: 17 Oct 2006

You bastard, my kids are going to hate me tomorrow Twisted Evil

I can just make 20k out, not uncomfortable. I was also wearing head phones.
Am in me early 30's. The 15k is uncomfortable so I guess I can't hang out in the car park with my skater mates any more.
Sad

Alyallen · Posted: Thu Sep 20, 2007 1:18 am Post subject:

CasperTheFriendlyGhost · Joined: 28 Feb 2007

Many speakers today don't register frequencies that high. Some cheap speakers don't do up past 15 kHz. I've sen speakers rated as low as 12 kHz in dollar stores.

faster · Joined: 03 Sep 2006

normalcyispasse · Posted: Thu Sep 20, 2007 5:32 am Post subject:

18khz here. I think this could be fun if the external speaker on my hand-phone were capable of 19khz.

Sample the MP3, loop it for a couple minutes, surreptitiously turn it on during a noisy class. . .

bassexpander · Joined: 13 Sep 2007 Location: Someplace you'd rather be.

The speakers in my classroom actually were LOUDER at the highest Khz ranges. Some kind of funky distortion going on!