Peter Shute [naturerecordists] writes:
> I listened to Ruffed Grouse on this recording:
> http://www.xeno-canto.org/153365
>
> I don't know how that recording compares to yours, but I can hear it ok on my
> PC speakers, which have cones about 5cm diameter, but much better on my
> MDR-7506 headphones, which have 4cm drivers.
Peter,
There weren't any details about how this was recorded, but the grouse stands
out distinct from the general soundscape, probably very close to the mics.
The spectrum peaks above the other sounds at +30 from 5Hz to 170Hz, well
into woofer range.
> On a side note, the Xeno Canto spectrogram doesn't really do the drumming
> justice, showing it as insignificant dots at the bottom of the scale, and
> doesn't even show the end of the sequence. I wish they'd show live
> spectrograms as you play the recordings.
The spectogram doesn't match up, full stop.
From the download, The waveform shows a single pulse with a half wavelength
of 8.6ms corresponding to a frequency of around 58Hz - not good on laptop
speakers. I would have expected to hear some reverb or harmonics. but it is
a single clean pulse. Is there any other bird which emits a single frequency
call without harmonics? On a power spectrum of the whole recording, the
frequency range of the LF call, 30dB higher than the peaks of all of the
rest of the power spectrum, spans 5Hz to 170Hz between the +30 peaks. At 300
Hz, it plunges to noise levels at 44dB below peak at 300Hz. This bird is
putting out an extremely "harmonically clean" call.
I'd love to hear Jennifer's recording.
David Brinicombe
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