Jordan:
I just read the first 4 papers listed on this
link: http://www.ars.usda.gov/pandp/docs.htm?docid=3D11072
My comments were based on those papers and my personal experiences with
geophones. Bear in mind that Mankin and his colleagues are not going to tel=
l you
every detail of what their technique is; follow the outline in the papers f=
or
the methodology & gear list, then look up the gear and read the data sheets=
&
application notes for them from the manufacturers. Remember that all transd=
ucers
must 'work' into the proper type of preamp with the right input impedance,=
filtering/integration, etc. or you will have bad results. The manufacturers=
will
tell you what to do in that regard.
Here is Richard Mankin's main
page: http://www.ars.usda.gov/pandp/people/people.htm?personid=3D3559
I'm sure you could drop him a line and he would be happy to help you out.
I should also mention that David Dunn has worked with recording insects wit=
hin
trees and also other creatures that have utterances in the ultrasonic range=
. If
you scour the web you can find a paper he wrote about constructing various=
inexpensive mics, insertion/contact transducers and a hydrophone. I'm afrai=
d
that I don't have the exact references handy to pass on. Bernie Krause has =
also
done some 'non-conventional' [not necessarily using mics] sound recording w=
ith
hydrophones, etc. Perhaps he can shed some light on this area. But in my
experience, no matter how much info you get from people you will still have=
details to work out on site in the field and constant practice is the only =
way
to get good results.
The biggest issues that I have encountered during insect recordings are win=
d,
ambient noise and the self-noise of the recording gear when you have the ga=
in
cranked up. Keep these 'big 3' in mind when you are formulating your method=
ology
and when you are putting together your equipment list. If you have a partic=
ular
question about a piece of gear that you can't get answered from the
manufacturer, contact me off-list and I will try as well as I can to help y=
ou
out.
Good luck with your quest! Please keep us informed of your work.
-Greg
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