David Ellsworth wrote
> My filtered versions are from a properly decoded version of the file.
OK, I initially did not fully understand the filtering procedure that
you applied (I now understand that you applied some kind of amplitude
demodulation).
> I do not think Doug's recording is of an insect;
> I think it is electrical interference from a
> power line. It's just too much of a coincidence
> for it to be so close to 120 Hz (60 Hz really,
> with that alternating amplitude). Listen to
I agree, this is obviously a amazing coincidence.
>
http://ad2004.hku.nl/naturesound/David_Ellsworth/insect_hi_freq1.filtered2.=
wav
> =97 I don't think a cricket could maintain such a perfect pattern.
Such "perfect" patterns are quite common in insects. They often sound
artificial or mechanic to the human ear:
Great Green Bush-cricket:
http://www.avisoft.com/sounds/tett_vir.wav (slowed-down)
Eastern Green Bush-cricket:
http://www.avisoft.com/sounds/tett_cau.wav (slowed-down)
More samples can be fount at:
http://www.avisoft.com/sounds.htm#insects
Raimund
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