for cheap, tough good, hydrophones look at www.cetaceanresearch.com. Ask to
Joe Olson if you need tips about building simple hydrophones.
stridulation is the typical sounds produced by some insects that use to rub
a "plectrum" on a "pars stridens", that is a surface covered with thin
ridges, to make sound. Often the plectrum moves back and forth on the pars
stridens. In such a case the sound is a double chirp with pulses having
opposite phases, according to the movement of the plectrum.
In some cases the contact in only during one movement and this produces
chirps that have pulses with the same phase, separated by longer gaps to
allow the plectrum move without producing sound.
On http://www.unipv.it/cibra/insec.html you can see spectrograms just about
this topic (ants and beetles).
I'll add sound samples.
Gianni
At 22.24 21/06/2004, you wrote:
>--- In Gianni Pavan <>
>wrote:
> > Hi Rich,
> > I don't understand what is your goal. Just to have a
>sensor to
> > detect their movements or are you interested in their communicative
>sounds ?
> >
> > In the past I recorded many species able to stridulate.
>
>My goal was actually to understand piezo pickups more than I
>currently do. I am on the road to building a decent hydrophone which
>I can not afford so need to read and experiment. So after wiring a
>piezo direct to a mic input that Rob gave me from his junk box I just
>walked around listening to everything from car engines to
>refrigerators.
>
>I am interested in ant communicative sounds but was just surprised to
>detect what I can not hear. And the word "stridulate" is actually
>new to me as well. I have some reading to do for sure. Thanks for
>the offer and may take you up on it when I get the basics behind me.
>
>My condensor mics don't seem to be able to pick this ant up and I
>stoped at a 22,000 sample rate because I figured I would need a small
>mp3 or no one would bother.
>
>I have not posted to the equipment list of members here either
>because all I would have to say is I own an extensive junkbox in
>which "stuff" has either been modified or is about to be. So I guess
>my equipment list would be mere stridulations.
>
>Rich
>
>
>
>
>"Microphones are not ears,
>Loudspeakers are not birds,
>A listening room is not nature."
>Klas Strandberg
>Yahoo! Groups Links
>
>
>
>
--------------------------------------------------------------
Gianni Pavan
Email
Centro Interdisciplinare di Bioacustica e Ricerche Ambientali
Universita' degli Studi di Pavia
Via Taramelli 24, 27100 PAVIA, ITALIA
Tel +39-0382-507874
Fax +39-02-700-32921
Web http://www.unipv.it/cibra
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