On Fri, 09 Feb 2007 01:20:02 GMT, "Ed" <ed@[EMAIL PROTECTED]
>
wrote:
>Has anyone ever performed an experiment measuring sounds normally unheard
by
>humans
>such as higher frequencies which can be heard by dogs and lower
frequencies
>?
>I imagine the sounds could then be transcribed to lower frequencies.
>
in europe and many parts of the USA listening to the frequencies above
" human " hearing is a BIG thing .... and even on ebay the devices to
do that are popular.
http://www.econvergence.net/batdet.htm
http://www.magenta2000.co.uk/kits/861.htm
http://www.batbox.com/Page3.htm
it's called " bat detectors " as a hobby and thousands of people
( mostly in europe ) listen in to the sounds above human hearing.
the point being that thousands of people are listening but NOT
hearing anything related to ghosts or the paranormal. just bats,
fish and insects. anything at all unusual would stick out like a
sore thumb and nothing unusual ( like ghosts or paranormal stuff )
is " EVER " observed.
listening to sounds below the range of human hearing is called
" infrasonics " . to hear infrasonics a person must convert the lower
sounds UP to higher sounds ( not a practical thing because
a 2 hz wide , 10 hz infrasonic sound represents too little
information to be heard by a person's ear ) infrasonics are mostly
observed on FFT spectrum display programs like the freeware
Spectrum Lab and many others. it is also observed using a
cheap dataq ( $25 ) a/ d converter and a PC or laptop.
a home made infrasonic detector ( or microphone ) can be made from
air conditioning duct parts as shown on this site .......
http://www.belljar.net/microbar.htm
also see
http://www.gi.alaska.edu/infrasound/Infrasound25.htm
the government has 24 / 7 infrasonic listening stations
all around the world and many people , world wide ,
like to eavesdrop on infrasonics as well . events attributable
to ghost whispers , paranormal or even unexplained
infrasounds sounds are NEVER experienced or recorded ,
world wide.
you can easily do any of this yourself using the links or google the
topics mentioned above .
just fyi .......
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