--- In "tk7859" <> wrote:
> Looking a bit more closely at it in Raven Lite I see most of the calls occupy
> 44 to 48 kHz. There also seem to be some a little lower at 40 to 42 kHz.
>
> I definately saw the bats so I'm sure the LS-10 recorded them.
>
> Must try some other microphone/recorder combinations.
An update on the bat work with the LS-10.
A Naturercordists member, Ralph, contacted me off list and offered to analyse
the recording with SonoBat. Analysis was a little difficult because the calls
were upardly truncated at 48kHz; a function of the 96 kHz sampling rate used
(maximum on th LS-10).
However after spending a bit of time surfing the net for British bat sounds we
think it might be a Common Pipstrelle. The link below leads to a bit about
their echo location calls. It could well be that what the SonoBat analysis
showed was the bottom bit of one of their hunting calls which range from
54.7kHz down to 45.1kHz, with the maximum power of the call around 48kHz.
http://www.bio.bris.ac.uk/research/bats/britishbats/
Many thanks for your help Ralph. Thanks also to Richard for his off list
interest in the topic.
I had another go at recording on Sunday evening. This time I used the
lightweight, Panasonic WM61A equipped, head spaced barrier described in my
earlier post today. BTW this weighs 11 ounces (312 grams) inluding the long
handle and ear muffs.
I wanted to use the Panasonic capsules with the LS-10 because I had read posts
by another Richard (also a member of Natrerecordists) on the WSRS forum and the
Bat Conservation Trust Discussion Forum to the effect that the WM61A capsule
has an extended frequency response and would be useful as a poor man's bat
detection microphone. Using this mic would herefore be a good test to check
how the LS-10's built in mics performed.
Fewer bats were around but I got some useful snippets. This time I announced
when a bat passed. All the passes were from right to left and this is
noticable (i think) in the sonograms of the stereo recordings. The sonogram
patterns are almost the same as those made on Saturday with the LS-10's built
in mics. I am thereore reasonably satisfed that the LS-10 is capable of
recording bat sounds with its built in mic (provided they are below 48kHz of
course- pity the max sampling freuency is 96k per second).
Below are links to the stereo sonograms made in Audacity. The first two are of
the Panasonic capsule equipped barrier and the third is that made with the
built in mics
http://farm4.static.flickr.com/3581/3483666496_f230c721cd_o.jpg
http://farm4.static.flickr.com/3311/3483667002_9f8fe5c0f1_o.jpg
http://farm4.static.flickr.com/3315/3474514282_83a55735a4_o.jpg
Also available for download are the original 24/96 WAV fles which are shown in
the Panasonic sonograms. Although they are less than 10 seconds long the are
quite big - about 3.5MB.
m("btinternet.com/panbat1A.wav","//uk.geocities.com/g0sbw");">http:
m("btinternet.com/panbat4A.wav","//uk.geocities.com/g0sbw");">http:
Another feather in the cap for the ever useful LS-10.
Cheers
TomR
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