The normal human hearing range is between about 12 and 20 kHz, but beginning around age 8 this range begins to shrink, and adults can no longer hear sounds above a certain frequency level.
www.ask.com/youtube?q=Sound Adults Can't Hear&v=RG0O478CQ-E
Oct 5, 2008 ... This is a high-pitched sound that people over the age of 25 shouldn't hear. The
sound seems to work better in a higher quality.
www.ask.com/youtube?q=Sound Adults Can't Hear&v=VoFGKwZxT_o
Nov 21, 2009 ... This is the sound adults over 30 cannot hear.(some may not qualify)Enjoy!plz
comment,rate and subscribe!
www.ask.com/youtube?q=Sound Adults Can't Hear&v=Tcs4QJWO7QY
Apr 12, 2014 ... Sadly as you get older your ears do to, so test your ears and see if you can still
make out this high pitched noise. Teens, check if your parents ...
Mar 2, 2015 ... Apparently, there's a noise that only people under 25 can hear. ... As you get
older, the hearing process (sound waves travel into your ear, hit your eardrum,
and vibrate three tiny bones, ... No, I can't ... PHOTO: Adult Swim.
Mar 3, 2015 ... On the flip side, teens are striking back by employing these pitches as ringtones,
so they can get calls that their parents and teachers can't hear.
... and sounds similar to a buzzing mosquito. The elderly and people with hearing
damage often cannot hear the sound. Can you hear this sound? Click to play.
Teens are effectively driven away, but many adults can't hear this sound at all!
Things got even more interesting when some kids realized they could turn this ...
These contain high-pitched sounds that Teenager Repellent "Mosquito" emits.
Will cause discomfort in certain people. In spite whether you can or can't hear, ...
This means that they can only be heard by kids and generally can't be heard by
adults over the age over 20 or so. See this article at the BBC to find out more.