The Teenager Audio Test

February 24, 2010 8:29 PM

The Teenager Audio Test "Clicking the play button below will produce a tone that is generally only heard by people under the age of 25. It has been used as a deterrent device to keep teenagers from loitering in malls and shops, and sounds similar to a buzzing mosquito. The elderly and people with hearing damage often cannot hear the sound." SLTO (Single Link The Oatmeal post)

This is the tone used by The Mosquito, a device marketed to solve "loitering problems" in Europe and elsewhere.

posted by sid (201 comments total)

FWIW, I'm in my late 20s and I can hear the tone. I guess I haven't joined the ranks of "the elderly" quite yet.
posted by sid at 8:31 PM on February 24, 2010

I'm thirty. Ouch.
posted by koeselitz at 8:32 PM on February 24, 2010 [1 favorite]

Previously.


/29, can hear it.
posted by furiousxgeorge at 8:33 PM on February 24, 2010

Yeah, it must depend to some degree. I have pretty bad hearing, but I can hear it fine (along with the high-pitched whine of televisions and electronics.) And I have at least two friends who can never hear the one planted in a nearby apartment complex.
posted by Solon and Thanks at 8:33 PM on February 24, 2010

Many years and at least one Hüsker Dü album too late.
posted by Joe Beese at 8:36 PM on February 24, 2010 [3 favorites]

I can hear it. It's telling me to kill.
posted by turgid dahlia at 8:36 PM on February 24, 2010 [45 favorites]

I'm 37 and I can hear it. Does that mean I have to stop loitering?
posted by swift at 8:37 PM on February 24, 2010 [3 favorites]

I have awful hearing, but I tend to have more trouble with lower ranges. Any kind of throaty muttering completely defeats me, and all I hear is a sort of muffled growl. Ditto anything with background noise, especially background noise with lots of bass. (This is one of many reasons I don't go to clubs.)

High pitched things, on the other hand, I can hear just find, and thank you so much for reminding me of that annoying sound televisions often make that people tell me doesn't exist.
posted by Scattercat at 8:38 PM on February 24, 2010 [10 favorites]

43 here. Heard it clear as a bell.
posted by Toecutter at 8:38 PM on February 24, 2010

I'm in my fourth decade and if you'll fetch me my loafers and my walker I'll happily get off your lawn to get that damned buzzing sound out of my hairy ears.
posted by Balonious Assault at 8:39 PM on February 24, 2010 [2 favorites]

I can hear it. It's telling me to chill.
posted by Kattullus at 8:40 PM on February 24, 2010 [4 favorites]

Can't hear it. Oh god my youth is really over, isn't it??
posted by contessa at 8:40 PM on February 24, 2010 [4 favorites]

30, and I can hear it. I also know exactly what that TV noise Scattercat referred to is; for the longest time I wondered how it was I could tell instinctively if a TV was on near me even if the sound was off, and sound turned out to be the answer.
posted by wanderingmind at 8:42 PM on February 24, 2010 [9 favorites]

31 and oh god I can hear it!!!
posted by yeloson at 8:42 PM on February 24, 2010

Eeek, loud! Also, Single Link Oatmeal Post should be SLOP ... which I think is a feature of the genre. Oh snap!
posted by Devika at 8:42 PM on February 24, 2010 [1 favorite]

I can hear it with my non-deaf ear. 35.

(scared the *shit* outta the cat, tho!)
posted by notsnot at 8:44 PM on February 24, 2010 [2 favorites]

I am nearly 42 and dont have great hearing and I can hear that tone just fine, even after a day of very loud Nine Inch Nails :D
posted by supermedusa at 8:44 PM on February 24, 2010

55. Seriously, are they even trying?
posted by SPrintF at 8:45 PM on February 24, 2010 [1 favorite]

Here are two pages with links to sound files of specific frequencies, along with the age cutoffs.
posted by sid at 8:46 PM on February 24, 2010 [12 favorites]

I'm two score plus one, and can hear it. However, it's pretty much the same tone and cycle as my tinnitus so it took me a moment to realize it was the tone and not just the ringing in my ears.
posted by jazon at 8:47 PM on February 24, 2010 [4 favorites]

35. No problem hearing it, and I'm a live musician.
posted by emelenjr at 8:48 PM on February 24, 2010

I can hear it, and I not only am 56 years old, but also mis-spent large swathes of my youth at overamplified rock concerts. (I can also be driven nuts by the hum of certain fluorescent lighting fixtures, like at a nearby supermarket. Talk about deterrent devices...)
posted by Kat Allison at 8:50 PM on February 24, 2010

34 and I can hear it. Perhaps the question is whether all us old fogies could hear it if there were ambient noise about.
posted by If only I had a penguin... at 8:53 PM on February 24, 2010

I doubt can most computer & laptop speakers can reproduce 17-20 kHz tones worth a damn. There's probably more about speaker & headphone worksmanship here than age.
posted by crapmatic at 8:54 PM on February 24, 2010 [5 favorites]

33. Have seen Merzbow, The Haters, Alice In Chains, Korn, Rage Against the Machine, among many others, live from the front rows with no hearing protection. And I can hear that sound just fine.
posted by idiopath at 8:54 PM on February 24, 2010

Uhm, interesting. I can hear the whine of a television set that turns on in another room (CRT of course, not LCD) but I can't hear this. I wonder if it's because I'm on a laptop with crappy speakers, or if it's because I'm 39 and old and it's the fucking end of the world aaaaaaaaaaaaaaaaaaaaaaaaaaaaaah!
posted by davejay at 8:55 PM on February 24, 2010 [1 favorite]

I can really hear it for a few seconds, and then it's as if it switches to a less audible version...is anyone else getting that?
posted by redsparkler at 8:57 PM on February 24, 2010

38, can't hear it. Thank you very much, Keiji Haino, Steve Albini and Stefan Jaworzyn for burning out my eardrums.
posted by porn in the woods at 8:57 PM on February 24, 2010

This is not the Mosquito Tone. It's much lower than that. I'll look at it in Audacity in a few minutes, but I don't think MP3 files can go anywhere near high enough to reproduce it.

By ear, I'd guess it's about 14Khz.
posted by Malor at 8:57 PM on February 24, 2010

30, can hear it, wish I couldn't.
posted by Ruki at 8:57 PM on February 24, 2010

I can hear it and I've been to an Acid Mothers Temple show with no earplugs.

Actually, I think I have a better version of this tune on a compilation CD of early 20th century electronic music.
posted by fuq at 8:58 PM on February 24, 2010

I'll be 42 soon and I can hear it fine. Does this mean I can date teenagers now, or is that still creepy?
posted by MegoSteve at 8:58 PM on February 24, 2010 [3 favorites]

43. I can hear it. I have hearing damage in my right ear from a q-tip incident while riding a bus, so high tones are cut. This site is probably just playing a normal tone while it installs a virus.
posted by mecran01 at 8:59 PM on February 24, 2010

Did they say what frequency it is?

There's also the matter of your speakers: cheap speakers are often not so good above 12 kHz (I can hear it on my cheap laptop, at 29).
posted by Monday, stony Monday at 9:00 PM on February 24, 2010

Late 40s and half deaf in my right ear. And yet I can hear it.

So you damn kids can hang out on my lawn for a little while longer it seems...
posted by Windopaene at 9:00 PM on February 24, 2010 [1 favorite]

41. ow ow ow. shit like this is the reason I don't go in posh electronics/department stores.

TV-wise, I once noticed that our color TV did it but the B/W one didn't. anyone else hear that?
posted by toodleydoodley at 9:00 PM on February 24, 2010

Oy, jesus god. This 36 year-old ex-punk rocker and still bassist can hear it fine.
posted by freshwater_pr0n at 9:00 PM on February 24, 2010

28, can hear it and JESUS CHRIST I HATE IT. That would definitely make me stop loitering in whatever the place was that was producing it.
posted by penduluum at 9:01 PM on February 24, 2010

31, and if you want really annoying ultrasonics (assuming they haven't changed the security system), go to the Smart Museum near Uchicago. When I visited that place I almost threw up.
posted by oonh at 9:05 PM on February 24, 2010

32, can hear this fine. Sounds like an mp3 player crashed to desktop with a split-second snippet of audio left looping constantly. Which is a bit surprising, because I expected the sound to be the mythical lightbulb whine that some of my more.... shall we say special snowflake-ish co-workers complain about.

That's not to say I've survived this long without damaged hearing: I have a hearing problem that keeps me from being able to discern individual sound sources within some noisy environments - I have all kinds of trouble holding conversations in pubs after they make the transition each evening from bars to nightclubs.
posted by MarchHare at 9:07 PM on February 24, 2010

Late 40's here. I could not hear it at normal sound levels on my pc, but when I jacked it up, I could hear it. I have diagnosed hearing loss for those sort of ranges too.
posted by JohnnyGunn at 9:08 PM on February 24, 2010

It's about 14,250Khz, much lower than the Mosquito Tone, which is about 17.5Khz. I'm surprised the MT is that low, actually, I was expecting it to be close to 20. Many kids can hear over 20Khz... I could hear to 28 when I first tested it, around 14. (it dropped off sharply in my 20s). My siblings were similar, although I don't think they ever explicitly tested themselves. All of us could tell if one of the 1970s-era TVs were on inside a house, even if the normal volume didn't reach the door, because we could hear them ringing in some ridiculously high register.

Most MP3 encoders have a cutoff at 16Khz, so while the format might technically be capable of going that high, I don't think you can actually generate such a file easily. You need WAV or a lossless codec.

So, if you can't hear the linked tone, if you're under 50, that likely means you have substantial hearing damage. 14Khz really isn't very high.
posted by Malor at 9:12 PM on February 24, 2010 [6 favorites]

42, heard it easily even without the two cats sitting on the couch next to me and my laptop going "wtf mom?"
posted by immlass at 9:12 PM on February 24, 2010

I'm 19, but I can only hear it if I turn the sound on my computer all the way up.
posted by mollywas at 9:13 PM on February 24, 2010

41, I can't hear it.

My 37-year-old wife wants me to make "that fucking hellish noise stop."
posted by Cool Papa Bell at 9:14 PM on February 24, 2010

This is not the Mosquito Tone. It's much lower than that. I'll look at it in Audacity in a few minutes, but I don't think MP3 files can go anywhere near high enough to reproduce it.

By ear, I'd guess it's about 14Khz.

My girlfriend recorded it in Praat. It's about 15kHz.
posted by HumuloneRanger at 9:14 PM on February 24, 2010

35. I can hear it.

I guess you are only as young as the teenage deterrent device you can feel in your ear canal!
posted by crossoverman at 9:15 PM on February 24, 2010

This seems bogus. I'm (sob) over 50 and I can hear it just fine. I know, however, that my hearing has deteriorated from my youth, and I think this tone is not a particularly high frequency.

If I listen to a frequency-based test, I find that I'm not able to hear anything about 12Khz, so the fact I can hear that tone makes me think the frequency is noticeably lower than that.
posted by CheeseDigestsAll at 9:16 PM on February 24, 2010 [1 favorite]

Um, 29 and neither my wife or I can hear the 14Khz. She can't even hear the 12Khz. Should we see a doctor?
posted by leotrotsky at 9:20 PM on February 24, 2010

On review, I see that it's been measured at 14KHz or so. Did anyone look at it with an oscilloscope? Different wave forms will include harmonics, I wonder if that's why I can hear this sound at 14K but not the one at noiseaddicts.
posted by CheeseDigestsAll at 9:20 PM on February 24, 2010

53 and can hear it over my screaming tinnitus.
posted by threadbare at 9:22 PM on February 24, 2010

I'm 56, deaf as a post according to my wife, have tinnitus, and I can hear it. Not a very satisfactory test, IMO.
posted by pjern at 9:22 PM on February 24, 2010

OOOOOOOWWWWWWWWWWWWWWWWWW!

I've always been able to hear these things, and they hurt a lot. I'm actually a little annoyed that people play things like this. Smacking people isn't okay, so why are they allowing a tiny man to smack me in the ear drum with a hammer?
posted by Phalene at 9:23 PM on February 24, 2010

I'm starting to think that this may be a joke, what with it being on a humor website and all.
posted by Kattullus at 9:24 PM on February 24, 2010

Not only can I hear it, I am now aware of the whine of my other electronics. Damn you oatmeal!!!
posted by psycho-alchemy at 9:24 PM on February 24, 2010

Also my mildly deaf boyfriend just yelled at me.
posted by Phalene at 9:24 PM on February 24, 2010 [1 favorite]

Katullus: nope, my cats can hear it for sure.
posted by leotrotsky at 9:25 PM on February 24, 2010

I'm 40 and have tinnitus, and the tone actualy made me wince. But I can also hear the hum of a television anywhere in a house.
posted by ten pounds of inedita at 9:26 PM on February 24, 2010

Mollywas: I can hear that lower tone too when I turn up the speakers. I don't think that's the tone they're talking about.
posted by leotrotsky at 9:27 PM on February 24, 2010

Haha, some guys in the office next to mine were experimenting with this noise a few weeks ago to see if they could hear it, which I guess they couldn't. Meanwhile, all of us in my office were going "Oh my god, make that noise stop!! What the hell is that?!" as it kept getting louder and louder because they were turning up their speakers to see if it just wasn't loud enough.
posted by crinklebat at 9:29 PM on February 24, 2010

Got freaked out for a second when I couldn't hear this (26), but then I could hear all the way up to 20k on the other sites--I suspect it's some sort of browser issue.
posted by PhoBWanKenobi at 9:30 PM on February 24, 2010

leotrotsky: nope, my cats can hear it for sure

I meant that the joke was that everyone could hear it.
posted by Kattullus at 9:33 PM on February 24, 2010

I think The Oatmeal are fucking with us.

I downloaded an app for the iPhone called "Dog Whistle", and it lets you select the frequency of the sound and it plays it. I have found that undergrads and young grad students (e.g., under 25) scream BLOODY MURDER when I play it. Other folks do not.

And that is why when I want to have a decent conversation, I make sure to use that app.
posted by barnacles at 9:34 PM on February 24, 2010

I should mention: 32, and I can definitely hear it. The Dog Whistle app I mentioned? I can't hear the stuff that drives the under-25s crazy, but man, it TOTALLY drives them crazy.
posted by barnacles at 9:35 PM on February 24, 2010

41. Can hear it.

Whoo hoo! I'm still cool!
posted by Astro Zombie at 9:36 PM on February 24, 2010

I don't know if it's my headphones or the sound file itself but there a lot of subharmonics present that pretty much anyone would be able to hear.
posted by delmoi at 9:40 PM on February 24, 2010 [1 favorite]

I'm 39 again^*, and the sound made me recoil. Son of a gun. Or maybe it's a lower frequency setting delivered in the online test. 'The Mosquito' system has such an option: The newest version of the device, launched late in 2008, has two frequency settings, one of approximately 17.4 kHz that can generally be heard only by young people, and another at 8 kHz that can be heard by most people.
posted by Kronos_to_Earth at 9:41 PM on February 24, 2010

I'm 22 but can't hear it--I have a moderate hearing loss in both ears.

My cat is 12 and looked at me funny when I played it for her.

If it's a high frequency noise that is obnoxious enough to actually repel teenagers, I'm kind of glad I can't hear it.
posted by autoclavicle at 9:44 PM on February 24, 2010

Another problem is that most computer speakers use 44khz sample rates, so frequences at 22khz are perfectly represented, while slightly lower or higher frequencies won't be reproduced properly.
posted by delmoi at 9:47 PM on February 24, 2010

33, have permanent ringing in my ears from a youth of playing in and going to see rock bands. I can hear it, and it makes me want to stop loitering in my own room. Awful sound.
posted by Saxon Kane at 9:50 PM on February 24, 2010

I want to purchase this in sonic gun format so I can clear teenagers out of the theater when I go to see movies.
posted by Saxon Kane at 9:56 PM on February 24, 2010

Another problem is that most computer speakers use 44khz sample rates

Speakers are analog devices, and don't use sample rates.

Most PC sound hardware, OTOH, uses 48Khz sampling, and that will put a hard limit of 24Khz on its reproduction. Typically, you have to explicitly change things to get 44.1Khz sampling. Many current-gen soundcards and motherboards can go as high as 192Khz, but again you usually have to explicitly ask for it.
posted by Malor at 10:04 PM on February 24, 2010

wat
posted by maortiz at 10:04 PM on February 24, 2010

Ow. My rabbit and I both hate that. She even stomped her foot at me. I've always thought that I heard this kind of noise around Sunset and Gardner in LA but my Googling has failed to confirm that that's what it is. I've even thought about doing an AskMe about it. Anybody know?
posted by Thin Lizzy at 10:05 PM on February 24, 2010

It's about 14,250Khz

Well, that was a stupid thing to say. It's either 14.250Khz, or 14,250Hz. 14,250Khz would be impressive.
posted by Malor at 10:06 PM on February 24, 2010

You know what's hilarious? Clicking on PLAY, not hearing a thing, then eventually realizing that I have the sound turned off on my speakers. THAT'S what makes me old.
posted by Ron Thanagar at 10:09 PM on February 24, 2010 [8 favorites]

Sounds like a 14k tone, yeah.

The Fletcher-Munson Curve is an equal loudness map of human hearing. Pretty much means we hear things around 7k (and multiples thereof, to an extent) as louder. Also, 7k is known to feel "piercing" to the human ear. This is why you frequently will find them on Emergency Broadcast Systems and big ass trucks backing up. Really gets the attention.


Also, human hearing degrades at the edges first, barring substantial damage that rips the hairs right out. So things sub 800hz and above 13k ish are the first to go. So it sounds like their thinking is to take a piercing frequency (14k being a direct multiple of the 7k classic piercing tone) but put it on a higher range so its more likely that young people with fresher ears will hear it more than older folks.

It's not terrible reasoning, but in practice I don't think it has the consistency to work.
posted by lazaruslong at 10:10 PM on February 24, 2010

HI EVERYBODY. WHAT ARE YOU GUYS TALKING ABOUT?
WHAT?
WHAT?
WHAT?
posted by Kraftmatic Adjustable Cheese at 10:12 PM on February 24, 2010 [2 favorites]

27, I can hear it even after loud machinery/concert damage. I had to turn it up to hear it over my low-level tinnitus.

Hearing it does make me feel like a teenager, though, because it makes me HATE THE WORLD.
posted by sleeping bear at 10:13 PM on February 24, 2010 [1 favorite]

For an easy example of this, check out this page that side linked above:

sid: "Here are two pages with links to sound files of specific frequencies, along with the age cutoffs."

On the pages link, click 8k. Yeah, it's high, but it doesn't really pierce. Same for 10 and 12k. Now click on 14k. Ouch.

Being 26, as well as an audio engineering grad (so I sorta know what to listen for / how to "feel" extremely high and low frequencies), I can't hear anything above 18k on computer speakers. I can get 18 on headphones or nice monitors with a clean high end range, but that's about it.
posted by lazaruslong at 10:14 PM on February 24, 2010

41 and can hear it fine.
posted by HP LaserJet P10006 at 10:24 PM on February 24, 2010

I've just turned 40, I've ruptured my eardrums a total of 5 times (maybe 6) in my life, and I heard that sound just fine.

Annoying, but fine.
posted by Dipsomaniac at 10:24 PM on February 24, 2010

I'm 14. a/s/l?

What the hell is going on in this thread?
posted by allen.spaulding at 10:31 PM on February 24, 2010 [2 favorites]

sid: "Here are two pages with links to sound files of specific frequencies, along with the age cutoffs."

I topped out at 16k. if I cranked it i could hear 17k, but i was worried that the cat might try and kill me
posted by joelf at 10:31 PM on February 24, 2010

IF ITS TOO INAUDIBLE YOU'RE TOO OLD MAN!!

30 and still with it, daddy-o!
posted by Alvy Ampersand at 10:38 PM on February 24, 2010

OK, I went to one of the pages that sid links and can hear about half of them...IN NO SPECIFIC ORDER. Are random dropouts in hearing common or is the technical issue here not made of meat?
posted by Kid Charlemagne at 10:47 PM on February 24, 2010

IF ITS TOO INAUDIBLE YOU'RE TOO OLD MAN!!

In all seriousness, if this tone is inaudible to you, you have substantial hearing loss and should see an audiologist.
posted by Malor at 10:49 PM on February 24, 2010

Judging from the reaction here and a few other peoples' comments, I hereby dub this the Make Your Cat Lose Its Shit Noise.
posted by Dormant Gorilla at 10:50 PM on February 24, 2010 [3 favorites]

I thought I couldn't hear it ... turns out I had unplugged my earphones. Heh.
posted by eritain at 10:50 PM on February 24, 2010

Well, okay, you might also have completely shit computer speakers. If you know gear is crap, don't panic.
posted by Malor at 10:51 PM on February 24, 2010 [1 favorite]

On the frequency pages, I could hear up 14 clearly, 17, 17.4 and 19 faintly (and at clearly the wrong tones), and none of the others. On the other hand, I was on a ferry crossing today with a bus load of junior-high-girl basketball players running around, so those frequencies may simply be exhausted.

Or my headphones suck. Or I'm old.
posted by maxwelton at 10:52 PM on February 24, 2010

Either I'm a freak of nature, or there's something wrong (or right?) with my computer speakers, because I can hear everything on those tone pages I linked to above, and I'm 27.
posted by sid at 11:08 PM on February 24, 2010

49, not a hint of the sound. Perhaps because I've played bass in R&R bands all my life?
posted by wsg at 11:11 PM on February 24, 2010

Too bad the brown note is around 9 Hz. Though setting it up as your friend's ring tone would be sorta funny.
posted by kurumi at 11:12 PM on February 24, 2010

39, and I think I can just barely make out the difference between playing and not playing. I guess I can't so much "hear" it, as notice when it changes. (It does stop after several seconds, right? Or am I imagining the whole thing?)
posted by ctmf at 11:13 PM on February 24, 2010

I can hear it, but then, my hearing is so acute that I had to hook up a pair of these to my speakers just to properly enjoy my CDs.
posted by Miss Otis' Egrets at 11:24 PM on February 24, 2010

BAM! Heard it on my 34th birthday. I'll hear you next year, fucker.
posted by jewzilla at 11:26 PM on February 24, 2010

OH FUCK THE PAIN MAKE IT STOP ICEPICKS IN MY EARS NOW CATS ATTACKING MY FACE WHY
posted by loquacious at 11:33 PM on February 24, 2010 [6 favorites]

40, and I heard it just fine. No hearing damage that I can think of, aside from some Auditory Processing Disorder stuff that goes with my ADHD.
posted by spinifex23 at 11:38 PM on February 24, 2010

Yargh, I can still hear to 20-21 kHz. No wonder I hate CRTs, TVs and ultrasonic pest repellers.

That or I'm some kind of overgrown rodent. BRB, gnawing things.
posted by loquacious at 11:40 PM on February 24, 2010 [1 favorite]

NO LOITERING ON THE INTERNET
posted by aubilenon at 11:49 PM on February 24, 2010 [1 favorite]

I can hear it, but I can also still hear the whine from some electronics. I can hear slightly higher frequencies than most people, in addition to my other superpowers of procrastination and disappointment.
posted by DecemberBoy at 11:49 PM on February 24, 2010

Oh, they compressed the tone to an MP3? Well shit, that's why everyone can hear it. MP3 is a lossy compression format, and the loss is mostly in the upper frequency range. That makes the test totally useless.
posted by DecemberBoy at 11:52 PM on February 24, 2010

When I was a kid I could hear the sonar sensors that started appearing at traffic lights to measure the flow of traffic at the intersection. Ued to drive me nuts if we were the first car when the light turned red, it was almost painful. Over the years I've lost that sensitivity. Now I can't hear this sound either.
posted by scalefree at 12:00 AM on February 25, 2010

Fifty and I heard it. Does this mean I must now cease loitering?
posted by philip-random at 12:21 AM on February 25, 2010

I'm 27 and can't hear anything.

I spent my teenage years playing in punk bands and enjoy my radio show in part because the in-studio monitors are capable of producing bass that I can feel, and that may very well be why.

That said, I think playing an apparently unpleasant tone like this as a way of getting teenagers to not loiter is a fucking asshole thing to do, and much prefer a method I read about a few years back: playing 60's pop hits.
posted by Pope Guilty at 12:45 AM on February 25, 2010 [1 favorite]

I could hear up to 17.4kHz using speakers connected to my laptop's headphone jack. Also got some funky artifacts a couple of times from the USB monitor speakers. I downloaded the WAV files off one of the links from sid's post. Not sure if I could hear 18kHz as I always get a click at the start and end of the clip, which is distracting.
posted by Soupisgoodfood at 12:48 AM on February 25, 2010

On this website I can hear the 8, 10, and 12 KHz sounds perfectly, but the 14 simply isn't there for me. This is actually kind of distressing; I can hear in my mind how it should sound based on the ascension of the tones, but when I actually play it it's like I'm deaf. That's very distressing on a deep level and I can't tell why.
posted by Pope Guilty at 12:49 AM on February 25, 2010 [2 favorites]

I'm going to get my hearing tested -- I cut out at 12KHz. Too many years too close to the speakers. But that means that the music I hear from other people's iPods on the metro must be incredibly loud. I think I'll print something out to give to them -- "if I can hear that you'll end up not hearing anything" or such.
posted by bwonder2 at 1:05 AM on February 25, 2010

delmoi: Another problem is that most computer speakers use 44khz sample rates, so frequences at 22khz are perfectly represented, while slightly lower or higher frequencies won't be reproduced properly.

Err, no that's not how it works...

Nyquist basically tells us that 1/2 the sample rate is the maximum that can can be *relatively* accurately reproduced (not "accurately", but "accurately enough"). Think what happens when you sample a sine-wave at f/2 - you get two points, one somewhere on the +ve 1/2 cycle, one at the equivalent spot on the corresponding -ve 1/2 cycle. Try to reproduce that from the samples without filtering, and you get a triangle / sawtooth wave. Even with filtering to restore the sine wave shape, you'll only get a truly accurate representation if you sample at the peak of each half cycle - otherwise you get the same frequency, but at reduced amplitude.

At frequencies above f/2 you get aliasing; correspondingly, the further below f/2 your signal, the more accurate the representation. This is precisely why higher sample rates are better - not because you can represent higher frequencies, but because the higher frequencies in the audible range are reproduced more accurately.

That said, I'd bet that if you're old and can hear it, what you're actually hearing is sub-harmonics introduced by the signal processing (.mp3 is actually pretty crap with pure tones) or your own speakers.
posted by Pinback at 1:10 AM on February 25, 2010 [1 favorite]

I couldn't hear the tone but it made my ears hurt just a tiny bit when I played it.
posted by stinkycheese at 1:20 AM on February 25, 2010

That said, I'd bet that if you're old and can hear it, what you're actually hearing is sub-harmonics introduced by the signal processing (.mp3 is actually pretty crap with pure tones) or your own speakers.

Is anyone listening? This is just a 14Khz tone. Anyone that can't hear this sound has either something wrong with their computer speakers, or significant hearing loss.
posted by Malor at 1:45 AM on February 25, 2010

I've always thought that I heard this kind of noise around Sunset and Gardner in LA but my Googling has failed to confirm that that's what it is.

Look for a pole with a double snorkel on the top of it, sort of like ET's eyes, focused on the first spot in line at the corner. If you see it that's a sonar sensor monitoring the flow of cars across the intersection. They use them to adjust the timing of the red & green lights.
posted by scalefree at 2:04 AM on February 25, 2010 [1 favorite]

Curiously, I can hear the tones all the way up to 21kHz but I can't hear the tone at the original link. I'm not sure what that means.
posted by scalefree at 2:05 AM on February 25, 2010

I bet Angus Young can't hear that buzz to save his life.
posted by ersatz at 2:11 AM on February 25, 2010

I can't hear it.

But I'm consoled by the fact that those of us who cannot hear it probably make more money than the ones who can.
posted by vacapinta at 2:34 AM on February 25, 2010

Hmmmm. How can I overthink this?

Me too!
posted by bam at 2:58 AM on February 25, 2010

Here;s something I prepared earlier. A range of frequencies to see where your hearing stops.
posted by Sparx at 3:19 AM on February 25, 2010 [1 favorite]

Oh stink. The link to the page worked but those sound links don't work anymore. Let me see if I can find replacements....
posted by Sparx at 3:22 AM on February 25, 2010

Here we go - now in flash.
posted by Sparx at 3:23 AM on February 25, 2010 [1 favorite]

hooray, i can hear a 20khz tone, i am supertwentysomething
posted by tehloki at 3:30 AM on February 25, 2010 [1 favorite]

jewzilla, same here. I also turn 34 today and can hear it just fine :)
posted by fonso at 3:36 AM on February 25, 2010

Crikey - using that flash app I cant hear past 15k. I am 38. ish
posted by Sparx at 3:38 AM on February 25, 2010

37 and can't hear a thing.
posted by zardoz at 3:44 AM on February 25, 2010

I can hear 15KHz (left ear only) but nothing higher. Would be more disappointed if I listened to anything other than doom metal.
posted by nowonmai at 3:48 AM on February 25, 2010

Whew, years of DJ-ing have me scared that my hearing is doomed, especially in my right ear, but I hear it. Early 30s.

happy birthday fonso
posted by spikeleemajortomdickandharryconnickjrmints at 4:34 AM on February 25, 2010

YMMV. Playing on my iBook's speakers, it sounds like a Dalek attack to me; on my computer's USB headphones, all but subliminal. With the better tests on the two pages sid linked to further down, I can hear the 15 khz test in both cases, which bullseye's me demographically. Considering I lived in NYC for a decade and always listen to portable music whenever I'm out of doors, I'll have to be content with that.
posted by Doktor Zed at 4:35 AM on February 25, 2010

Malor: Is anyone listening? This is just a 14Khz tone. Anyone that can't hear this sound has either something wrong with their computer speakers, or significant hearing loss,

Based on the flash version sparx linked to, it is not 14 Khz. I can hear 14 Khz just fine. 17, not so much, 18 not at all.
posted by Decimask at 4:36 AM on February 25, 2010 [1 favorite]

Ugh. Like a nano-dental drill.

I'm 40 and have to stand near the drummer and I can still hear this, so yay earplugs.
posted by ChuqD at 4:38 AM on February 25, 2010

I am in my late 60s, & heard it, but then I have to wear earplugs at concerts.
There is also a high b-flat playing.
posted by hexatron at 4:49 AM on February 25, 2010

Mid-30s and can hear it, but it doesn't really bother me. I wonder if I were younger I'd be able to hear it louder, somehow, and that it would be infuriating? This would seem to be germane to whether it "works" (ie, helps mall owners and others perpetrate a really obnoxious form of age discrimination that ought to be illegal)
posted by game warden to the events rhino at 4:56 AM on February 25, 2010

41 with constant ringing in my ears but I heard it loud and clear.
posted by rahnefan at 4:57 AM on February 25, 2010

Heh, we are assholes. This is actually the "How Old are the Mefites?" thread.
posted by rahnefan at 4:58 AM on February 25, 2010 [3 favorites]

45, long-time rock musician who spent years playing in front of very large amps and PAs turned up way too high.

I hear it just fine. I'm guessing 22KHz?
posted by fourcheesemac at 4:58 AM on February 25, 2010

39, I can hear it, but OHMYGOD!THE TVTONE!MAKE ITSTOP!MAKEITSTOP!MAKEITSTOP! So glad to know that I'm NOT nuts because I complain about that noise. Damn you, cable television! I miss the days when your TV turned "off" when you pressed "off," instead of just cutting off the cable feed.
posted by KingEdRa at 5:05 AM on February 25, 2010

34. Can hear it, goes well with the tinnitus.
posted by Blazecock Pileon at 5:09 AM on February 25, 2010

Yeah, their site needs another qualifier. "If you can't hear this, you are elderly, have hearing damage, or your speakers aren't on." I was a little worried for a second there.
posted by k8lin at 5:14 AM on February 25, 2010

a tone that is generally only heard by people under the age of 25

The elderly. . . often cannot hear the sound

Are they trying to say that 25 and up is classified as elderly?
posted by JanetLand at 5:18 AM on February 25, 2010

Am I the only one who doesn't mind the tone?
posted by Lucinda at 5:19 AM on February 25, 2010

I actually don't mind the tone for a short time. It sounds like high pitched radio background noise, definitely not irritating enough to make me get off The Oatmeal's lawn.
posted by edbles at 5:22 AM on February 25, 2010

32, can totally hear that shit. 33 year old musician boyfriend had his back to me when I clicked the play button and he was all "SWEET MERCIFUL CRAP BABY MAKE IT STOP" so I guess he can hear it too.

either that or it's time for an awkward relationshipfilter askme.
posted by palomar at 5:23 AM on February 25, 2010 [1 favorite]

Three years and many concerts, open cockpits and unmuffled engines later, yup. I can still hear it.

You're only as old as the frequencies you can hear. Not quite the same happy ring of "only as old as you feel," but I'll take it.
posted by 1f2frfbf at 5:43 AM on February 25, 2010

Very faint in my headphones with the sound at a reasonable level (calibrated to Andrew Bird's latest album). It doesn't really annoy me that much; kind of like a jacked-up TV test tone.
posted by Shepherd at 5:49 AM on February 25, 2010

Able to hear it once I remembered to turn up my speakers.
posted by StephenF at 5:49 AM on February 25, 2010

it makes my ears hurt, but i don't really hear anything.

it feels like i'm hearing something really piercing but i don't actually hear anything.

same thing happened when i tried the "mosquito" tone on the cell i used to have.
posted by sio42 at 5:50 AM on February 25, 2010

Me (31): This is stupid there is no sound being played.
Wife (29 and standing clear across the room): "Ugh.. What is that horrible noise"
Daughter (7 and in the other end of the house): "Hey what is that noise? I like it!"
posted by jlowen at 5:53 AM on February 25, 2010 [2 favorites]

I'm 51 and my husband is 52. We both heard it. And yes, it's obnoxious.
posted by St. Alia of the Bunnies at 5:55 AM on February 25, 2010

Couldn't hear a damn thing, with headphones on. Thought I had decent hearing. Interesting.
posted by sandraregina at 6:10 AM on February 25, 2010

If you can't hear it, good news! You can save hard drive space by downgrading all of your music files to 30 KHz.
posted by qxntpqbbbqxl at 6:14 AM on February 25, 2010 [2 favorites]

46, and I could hear the sound just fine. Now my problem is my desire to join the other meat units in service to our robotic masters.
posted by GenjiandProust at 6:15 AM on February 25, 2010

I have a funny feeling that many people here that can't hear it just don't have permissions set for their browsers to play music, or something akin to that.
posted by Theta States at 6:20 AM on February 25, 2010

It should be mentioned somewhere that if you have to jack up the volume, then you have problems hearing it. The sound itself is not weak in amplitude.
posted by tybeet at 6:23 AM on February 25, 2010

I'm 43. Checked out the flash page, and could hear all the sounds.

Husband (also 43), in the next room, yelled, "What is that NOISE?!"

Black cat (5 years old) came over and meowed pathetically until I comforted her.

Demon cat (2 years old) started kneading at my feet, but he's usually contrary, so that's no big surprise.
posted by misha at 6:34 AM on February 25, 2010

If I turn the volume up on my computer more than half-way, I can hear it faintly. I'm 59. Interestingly, when I played it at the louder volume my dog's ears perked up.
posted by Guy_Inamonkeysuit at 6:45 AM on February 25, 2010

I hear it only on my left ear (36).
posted by zeikka at 6:50 AM on February 25, 2010

I can hear it annoyingly loud and clear, and I'm in my mid 30's. I can hear it quite a bit less in one ear - but I already expected that, as that ear suffered noticeable hearing loss after an accidental metal-on-metal (well, okay, pot-lids) loud-noise incident several years ago. I can still hear it though.

Sounds like the "TV Sound" i've heard all my life, until we got rid of all the CRTs.....
posted by TravellingDen at 6:53 AM on February 25, 2010

I'm 27 and heard it clear as a bell. Incidentally, I hit play and my 2 year old son came running into the room with his hands on his ears.
posted by tylerfulltilt at 6:58 AM on February 25, 2010

It should be mentioned somewhere that if you have to jack up the volume, then you have problems hearing it. The sound itself is not weak in amplitude.

Interesting. Can you explain this? I had assumed frequency and volume were independent, but I don't really understand acoustics or anything.
posted by game warden to the events rhino at 6:59 AM on February 25, 2010

It triggered my tinitus. Great.
posted by sourwookie at 7:10 AM on February 25, 2010

I can listen to music just fine. And podcasts. And other things, through the headphones. I hit 'play' on that site, and get nothing. *shrug*
posted by sandraregina at 7:16 AM on February 25, 2010

51. Hear it. Don't like it much. Now back to my new mp3, "Dentist Drills and Chalk Board Fingernails"

Aaaaaahhhhh!
posted by Splunge at 7:25 AM on February 25, 2010 [2 favorites]

Yeah. I'm the type of person who can walk into a room and instantly know if an electronic device is present like a computer, tv, or radio is on even if it's not making any noise and even if I don't see it. It's especially true if a cd player is left on but nothing is actually playing in it.

I can hear this tone without any problems. I can also hear most of the ones here, though they get a little fuzzier after 17.4 khz.
posted by zizzle at 7:27 AM on February 25, 2010 [1 favorite]

I can hear it. I'm 56 worked on a web-offset printing press (110dB) in the era before OSHA mandated ear protection, went to a lot of rock shows (just saw Patti Smith last Friday, YAY). So what's the deal? I recommended the Mosquito to my community board as a way to keep the Yutes from congregating on the b-ball court after 10 pm. Now I don't know if we should bother spending the money. We don't NEED to keep 56 year-olds off the courts at night. WE pretty much always stay off the lawn.
posted by beelzbubba at 7:48 AM on February 25, 2010 [1 favorite]

cranked my speakers to maximum volume. dead silence. I'm 30.
posted by 256 at 7:51 AM on February 25, 2010

52 and tone comes in loud and excrutiatingly cringeworthy. Reminds me of why I spend very little time in certain stores.
posted by kinnakeet at 7:56 AM on February 25, 2010

I'm nearly 40 and heard it so loud on my headphones I twitched!
posted by agent of bad karma at 8:10 AM on February 25, 2010

It should be mentioned somewhere that if you have to jack up the volume, then you have problems hearing it. The sound itself is not weak in amplitude.

Interesting. Can you explain this? I had assumed frequency and volume were independent, but I don't really understand acoustics or anything.

IANAE but I've been reading an introductory textbook for my grad studies on psychoacoustics and hearing so this jumped out at me.

First, you have to understand that the human ear is optimized to hear frequencies between 1-5kHz. Second, many experiments testing a person's threshold of hearing will allow them to increase the level of the test sounds (which are at different frequencies) until they can hear it. A person with optimal hearing can hear a 1000Hz sound at levels of 1-3dB. Sounds at higher and lower frequencies are more difficult to detect. They do, however, become easier to detect with increasing sound level because a higher level means more energy is present in the sound which means more excitation of the hairs in the cochlea (up to around 100dB this is true) which means more potential for neurons to fire and therefore perception of the sound.

This is a chart between dB and frequency necessary for detection. This is a chart showing actual data from thresholds for persons between 20 and 60 years old (granted it's only 1-6kHz, you can see and reasonably extrapolate to higher frequencies which will require higher and higher sound levels for detection). Here's another using averages and going up to 90 years.

Someone aged 60 may not be able to detect a sound at 10kHz at 30dB, but crank it up to 60dB and they can hear it just fine. A sound at 14kHz may be undetectable at 60dB, but 100dB and it can now be detected. A 17kHz sound will be undetectable even beyond 100dB because our auditory system wasn't designed for that, and besides the hairs are so physically damaged at this area that chances are nothing will get them moving.

So my main point was that cranking up the sound on this may still indicate hearing loss, but the sound level is just being used to compensate for it. There should have been a referent sound used at another frequency, and done in 2 steps:

1) Adjust this 1000Hz tone until it is at the level you would hold a conversation.
2) Now play this 17kHz tone, can you hear it? If not, you're probably over 25 years old.

The other downfall of this test in the FPP, of course is that the tone in the first link is not actually 17kHz, it's closer to 14kHz and so it's no wonder most people over 25 can hear it!
posted by tybeet at 8:12 AM on February 25, 2010 [3 favorites]

*A 17kHz sound will be undetectable even beyond 100dB (for someone over, say, 60 years) because our auditory system wasn't designed for levels exceeding ~100-120dB... in fact volumes over 120 are usually experienced as pain.
posted by tybeet at 8:15 AM on February 25, 2010

Yep, checked it out in with Audacity, and it's 15.1 khz, and totally audible to my 41-year old ears
posted by pellucid at 8:29 AM on February 25, 2010

Not getting it, to my despair. I'm 37 and have had my share of live-sound blasts (many of them self-generated), but I've also done a lot of recording/mixing, and know I can hear changes in EQ up to the high teens at least. So either my work computer speakers are to blame, or I lost a lot of hearing since last week while strumming acoustic guitar around the house.... I really hope it's the speakers.
posted by Erroneous at 8:42 AM on February 25, 2010

39, can hear it, and say "Ha!" to the woman who got mad at me for wearing earplugs at a Girl Trouble show. Bet you can't hear it, unidentified woman! Who's cool now, huh? Not me, that's for sure.
posted by The corpse in the library at 8:54 AM on February 25, 2010

Apparently my 36-year-old ears cut off at 18khz. I can hear a 17khz tone, but when I hit 18 all I hear is the pop of static when the tone starts and stops.

My wife (8 months older than me) can't hear anything above 14-15 khz I think.
posted by caution live frogs at 8:55 AM on February 25, 2010

I've noticed a few symptoms of age-related hearing loss recently (I'm 58.3), and I heard it. Maybe the whine my furnace blower has developed lately isn't, as my daughter claims, entirely imaginary.
posted by cookie-k at 9:02 AM on February 25, 2010

Not sure if it's the food poisoning I have or if this is the "brown sound".

Great.
posted by stormpooper at 9:07 AM on February 25, 2010 [1 favorite]

I'm 45. I heard it and hated it.
Nobody has made a decent high-frequency tone since 1979.
posted by rocket88 at 9:18 AM on February 25, 2010

Huh. 17khz is the hardest for me to hear, but I can hear the ones above and below it better...? Yay ears!
posted by yeloson at 9:20 AM on February 25, 2010

NOTE to others: take computer off MUTE setting before panicking about impending hearing loss.
posted by whatzit at 9:27 AM on February 25, 2010

40. Heard it. Hated it. Want it off my lawn.
posted by jscalzi at 9:40 AM on February 25, 2010

This thread is just a ploy to get us to tell you our ages.
posted by desjardins at 9:43 AM on February 25, 2010 [1 favorite]

My girlfriend recorded it in Praat. It's about 15kHz.

That was going to be my guess once I listened, typically 15kHz is the frequency quoted when people talk about this kind of thing. When this first became popular, I made a sound file that jumped by 5000Hz increments from 14k up to about 19k, and played it for my coworkers, most people couldn't hear it at all, but those of us that could typically dropped off between 16k and 17k. For whatever reason, I can go up to almost 18 before it fades out.

It makes me crazy that I can still hear in this range, at 38 it doesn't really serve me any useful purpose to be able to hear non-tuned TVs and bats finding their way at night. And at my local grocery store, there is a conveyor belt in one of the checkout aisles that perfectly hits it every rotation, and it almost cripples me every time. We were standing there, and my wife and the person checking us out were completely oblivious, but the kid bagging the groceries and I were just writhing every time the thing went around.

Disc brakes on cars that are starting to wear hit in this range too, so driving in summer with the windows down is always fun.

And I swear, people look at you like you're insane, you suddenly start twitching and dodging going "Argh, make it stop!" and almost no one around you has a clue what you're going on about.
posted by quin at 9:46 AM on February 25, 2010 [2 favorites]

I actually took the sound file and used Audacity to do a frequency analysis, and it's almost all at about 14,250Hz.
posted by Malor at 9:49 AM on February 25, 2010

Well, if I zoom in on the graph, it's about 14,750.
posted by Malor at 9:50 AM on February 25, 2010

45 and heard it OK.
posted by Gridlock Joe at 9:54 AM on February 25, 2010

Okay, I went to that mosquito ringtones site, and I can't hear anything over 12 khz. Very interesting. My cousin is an audiologist, I will have to tell her.
posted by sandraregina at 10:02 AM on February 25, 2010

That said, I think playing an apparently unpleasant tone like this as a way of getting teenagers to not loiter is a fucking asshole thing to do, and much prefer a method I read about a few years back: playing 60's pop hits.

Or better yet, just play really good current music; that would clear out assholes of all ages.
posted by philip-random at 10:14 AM on February 25, 2010

I am 51 and on the mosquito ringtone site I can just barely perceive the 15Khz tone. It wavers in and out of perceptibility depending on how my ears are oriented to the speakers and feels almost as a pressure rather than a sound. The 14kHz tone is really obvious.
posted by bz at 10:14 AM on February 25, 2010

In Seattle at the base of a high-rise condo building (3rd and Lenora street-view) that has a lot of cover from the weather and is a natural loitering spot in a neighborhood where there's a lot of loitering (Belltown). Embedded in the ceilings over thew sidewalks is an extensive sound system with lots of speakers that plays straight opera--like, arias only-- 'round the clock.

Guess what?

No loiterers, ever.
posted by bz at 10:21 AM on February 25, 2010

32, I can definitely hear it. My cat, approximately 7, can also hear it (and doesn't care for it at all).
posted by sluggo at 10:24 AM on February 25, 2010

Now if only there was a well payed profession for a guy in his 30's who can walk into a room and tell if the TV is on before seeing it.
posted by Lokisbane at 11:23 AM on February 25, 2010

I will turn 38 this summer. Of late I've had trouble hearing and understanding my young children, but this came through perfectly. I am glad to hear that my hearing functions unimpaired -- and positively delighted that my limbic system is acting to protect me from whining about Bakugan, flute practice, and chores.
posted by wenestvedt at 11:39 AM on February 25, 2010

Pushing 40 and I could hear it (oh my god, I'm pushing 40!). It doesn't bother me the way it did when I was younger, though, so maybe I'm losing the range a little. I remember being a teenager and not being able to enter some jewelry stores because of the annoying high whine. When I asked, I was told "oh, that's the alarm system," which I assumed was why it was generally only expensive stores that had it. That was in the 80's before (as far as I can tell) anyone was using it as a deliberate teenager repellent, but the store clerks clearly knew what I was complaining about, and that most people couldn't hear it.
posted by Karmakaze at 11:54 AM on February 25, 2010

43 and can I hear it.
I wonder how much they turn it up because this would be annoying. I'm guessing most people can actually hear it if only the elderly or those with hearing damage cannot. Which means teens might just hear it a little louder than adults do.
posted by Rashomon at 1:26 PM on February 25, 2010

39, can hear it. That' ultra high pitch noise some TVs and whiteware make is also really annoying to me.

Does this 'only teenagers can hear it' thing have any validity at all?
posted by Sebmojo at 2:19 PM on February 25, 2010

Yeah that shit's awful, it's making me not want to loiter around the computer!
posted by Mister_A at 2:23 PM on February 25, 2010

Does this 'only teenagers can hear it' thing have any validity at all?

No, it's just that people's ability to hear high-pitched sounds falls off over the years and a high enough pitch is unlikely to be heard by anyone who isn't still young.
posted by Pope Guilty at 2:55 PM on February 25, 2010

I've still got it. I'm 31, and it felt like someone was trying to burrow into my brain.
posted by reenum at 2:58 PM on February 25, 2010

I used an audio test tool on my Macbook Pro, and either my laptop speakers drop off at 13,400K, or my ears do. Good to know, I guess.
posted by davejay at 3:54 PM on February 25, 2010

I remember a few years ago asking how many of my friends or co-workers could "hear" the whine of a CRT TV. Most of them said no, except the aspy-type nerdy ones. Most said they didn't even know what I was talking about.

I can generally tell if a CRT TV is on from several rooms away in the house... I always thought everyone could do this (hearing damage aside) - but apparently it's not the case.

Thank goodness for flat-panel TVs.
posted by TravellingDen at 6:44 AM on February 26, 2010 [1 favorite]

Nothing. My elderly dog, who is famously deaf and cannot hear her name, the sound of the can opener, or the word NO, completely started freaking out.
posted by mochapickle at 8:38 AM on February 26, 2010 [2 favorites]

TravellingDen: "I always thought everyone could do this (hearing damage aside)"

You are right. Hearing damage is so common as to be nearly ubiquitous, and is practically inevitable.
posted by idiopath at 8:50 AM on February 26, 2010

Another nearly-40 who can hear it just fine. JUST FREAKING FINE!

ow.
posted by batmonkey at 1:35 AM on February 27, 2010