I believe that it is a bush-cricket species. Unfortunately, I'm not an
expert in North American insects. However, there are similar species
here in Europe. For instance Roesel's bush-cricket (Metrioptera roeselii):
http://www.avisoft.com/sounds/metr_roe_.wav
(original speed, re-sampled at 44.1 kHz)
http://www.avisoft.com/sounds/metr_roe.wav
(slowed down version)
In order to make the HF sounds better audible, the original sample
rate of 220.5 kHz has been set to 22.05 kHz in the above file, which
provides a time expansion factor of 10.
Spectrogram with the original time and frequency scale:
http://www.avisoft.com/sounds/metr_roe.gif
Regards,
Raimund
--- In David Ellsworth
<> wrote:
>
> Doug,
>
> I measure 120.02 pulses/sec! There's a pattern which never deviates,
> in which every "even" pulse has a low amplitude and ever "odd" pulse
> has a high amplitude ("even" and "odd" are arbitrary of course). This
> means the actual period of the sound is 60.01 Hz, which really
> strongly suggests to me that this is an electrical disturbance from a
> power line. I'm going to write a program to measure the
> moment-to-moment deviation in the pulse rate; perhaps this can shed
> more light on whether it is too regular to come from a living creature.
>
> Have you found any pattern to the circumstances under which this
> pulse shows up in your recordings? It would be nice if you could
> record this at a higher sample rate. At 44.1 kHz, its spectrogram is
> cut off sharply, so we're not hearing the complete sound when it's
slowed down.
>
> BTW, I had to struggle to find a program that could open
> insect_hi_freq1.wav... turns out it is 32-bit floating point.
>
> At 2007-06-07 11:49, Doug Von Gausig wrote:
>
> >Every once in a while I notice these very HF insects in recordings -
> >they're often at 20,000 Hz and higher. When I resample them down to my
> >range and increase the volume, they sound like regular tree crickets.
> >They're often diurnal.
> >
> >I've posted an example at
>
><http://www.naturesongs.com/recordists/insect_hi_freq1.wav>http://www.natu=
resongs.com/recordists/insect_hi_freq1.wav
> >( or
> ><http://tinyurl.com/nd3y6>http://tinyurl.com/nd3y6). In this
> >example, recorded in central Arizona
> >today at 11 am (86 deg.F), the first 3 sec. are "raw" - you can see the
> >sound up around 21,000 Hz, the next 3 sec are resampled 4X, and the
final 3
> >sec are the resampled portion boosted 20dB, so I can hear it.
> >
> >The individual pulse rate is about 120 pulses/sec, so he's really
humming!
> >
> >What are these guys?
> >
> >Doug
>
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