Gooday birders
On the subject of enhancing sound for the hard of hearing. I made
inquiries years ago re a sound enhancing device that would allow me to
hear barely audible sounds at night. I was going to use it to listen for
and to owls and possums etc especially those that may be calling far off
and that I may not have otherwise heard. It would be interesting to
listen to sounds between possums etc and rustling in the leaves that we
may otherwise not hear with normal hearing. I have often wondered
whether dogs hear insect bats zipping about the place. We can hear a few
but the call frequency of most bats is above human hearing. Anyway, for
explanations sake we use binoculars to see details in distant objects or
to see close objects better. Why do we not have some sort of hearing
device, for folk with otherwise good hearing, that allows us to hear
faint sounds of a night or in quiet locations, so that rather than
cupping our hands to our ears and straining to listen we can put the ear
plugs in and point the device in whatever direction and hear clearly
sounds that we would not hear. I was told that if we did use such a
device and a sudden loud noise occurred we could be deafened. But the
same goes with binoculars when accidentally pointed at the sun or when
reflections on water are viewed. I hope you understand what I am talking
about. Has anyone heard of such a device and are they already available
at a reasonable price. I am sure the police and military already use
something like this.
Greg
-----Original Message-----
From:
On Behalf Of michael norris
Sent: Sunday, 10 December 2006 2:34 PM
To: Tim Murphy; Birding-aus
Cc:
Subject: Songfinder question
Bat detectors shift frequencies into the audible range with the cheapest
being about 100 Aussie dollars.
You can find the circuitry on the web.
There's an opportunity here for an entrepreneur to modify them to shift
bird
song to lower frequencies.
Michael Norris
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