But what do you call "normal scale"? If you zoom in a bit further you'll see
that the first note of each set of three is sometimes broken into two with a
sudden change in pitch. You can hear it more clearly if you slow it down.
What I find most useful about being able to see them as clear shapes instead of
blobs is that you can scan through a long recording and spot different species
calling without having to listen to it all several times over. Often you can
see them very faintly in an ambient recording where you might have missed them
when listening. The low frequency range is a very interesting place, often full
of soft hoots and coos and murmers. Sometimes a much more compressed time scale
is required to see a long drawn out call as a shape rather than just a line, so
there's no universal scale to use.
Just for interest, what program did you use to generate the spectrogram? And
what settings? This is where Audacity falls down a bit. You can't change the
FFT window overlap to sharpen it up at higher window sizes. I've asked them if
they can change this, but it seems to be hard coded in a way that they're not
interested in fixing.
Peter Shute
From: On
Behalf Of Jim Morgan
Sent: Sunday, 10 February 2013 6:00 AM
To:
Subject: Re: [Nature Recordists] Re: Sound spectrogram of a Eurasian
Collared-Dove (Streptopelia decaocto)
Hi Max,
I first looked at the spectrogram in the normal scale that displayed the
notes as thick dashes with little detail as to there real shape. Then I
looked at the spectra on an very expanded scale that revealed a huge amount
of detail. The surprise to me was the huge amount of detail.
I would be very interested in your spectra.
Best,
Jim
On Sat, Feb 9, 2013 at 11:46 AM, Max <> wrote:
> **
>
>
> Hi Jim,
> I'd be interested to know why you were surprised at the result? I have
> these birds in my garden all day long, but unfortunately live in a noisy
> situation close to a major trunk road. Once they get into full song again
> I'll make a recording and compare with your speccy.
> Cheers
> Max
>
>
> --- In Jim Morgan wrote:
> >
> > I expanded the scale of the Eurasian Collared-Dove recording so the
> > spectrogram would show the shape of the individual notes. I was
> > surprised at result and thought that some of you might be interested.
> >
> > Here is the recording that is the same as the previously posted
> > recording: http://soundcloud.com/fundador/557-eucdo
> >
> > And here is the spectrogram:
> >
> https://picasaweb.google.com/fundador.photos/EurasianCollaredDove#slideshow/5842974566215133938
> >
> > Jim Morgan
> > Prescott AZ
> >
>
>
>
------------------------------------
"While a picture is worth a thousand words, a
sound is worth a thousand pictures." R. Murray Schafer via Bernie Krause.
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