> I have recorded a bat with a standard mic, so it's not as good as
> you would get with a ultrasound mic or a bat detector of some kind.
Wanna bet? The mics in affordable bat detectors are no great shakes
either. They are often Knowles capsules or similar which still have a
response at bat frequencies but by the time they are HF boosted, they
get quite hissy. Many electret mics have a useful extended HF
response.
> What is the best way to work with the file in post?
Any suggestions?
Fork out two zeroes for a specialist bat analysis program or use free
Audacity which gives you all you want. Parameters are:
Call start frequency
Call end frequency
Repetition rate and pattern - regular or irregular
Shape of call - FM (sweep) or CF (constant frequency)
or a combination - a "hockey stick" call
On Audacity you look at:
Overall call pattern waveform with timing
Normalise the call or part and display the sonogram <spectrum>
Select a single call and display the power spectrum
<Analyse - Plot Spectrum>
That's about all that a commercial bat package does. The rest is info
and a library of bat species calls.
See Wiki "Bat detector" and Wiki "Bat species identification" I
expanded the types of bat detector and put some sample displays on the
second one.
David
David Brinicombe
North Devon, UK
Cogito cogito ergo cogito sum - Ambrose Bierce
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