ger
Date: Sun Aug 15, 2010 3:56 am ((PDT))
A sound spectrogram (sonogram or sonagram) can certainly reveal finer detai=
ls within a phonatome (a sound element of a calling or singing animal, a sy=
llable) than the human ear is capable of discerning. As an illustration I w=
as comparing recordings of Gryllus veletis at 48kHz sampling rate vs 96kHz =
sampling rate. There was a distinctly audible different in the recordings w=
ith the 96kHz having a cleaner, clearer sound. However, there was no way th=
at I could say why that was the case. Looking at the sonograms I could see =
a lot more fine detail within the chirps at 96kHz. Since the recorder was s=
ampling the sound at twice the temporal resolution the sonogram was clearer=
and I could discern an audible difference. However, my ears could not begi=
n to hear all the fine details within the chirps that I could see in the so=
nogram.
Bioacoustic technicians use the sonogram to differential the nocturnal call=
s of migrating birds with greater precision than the human ear can discern =
all in an effort to automate the tallying of species reordered during a nig=
ht of migration. There are also some North American tree crickets that are =
hard to tell apart with just the ear. Using a recording and looking at the =
sonogram it is easy to identify the species observed.
Wil Hershberger
Nature Images and Sounds, LLC
Hedgesville, WV
The Songs of Insects
My Blog
On Aug 15, 2010, at 4:56 AM, Raimund wrote:
> I think that it all depends on which property of the sound you are intere=
sted in.
>
> For instance, a spectrogram or spectrum can provide (depending on its set=
tings) more precise frequency measurements than the human ear. It can also =
provide a better temporal resolution.
>
> But I would agree that a common spectrogram is not very well suited for v=
isually comparing sound amplitudes. Nevertheless, some spectrogram applicat=
ions also allow to measure amplitudes (magnitudes) precisely by using cross=
-hair cursors.
>
> Regards,
> Raimund
>
>
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