Richard,
with respect to Roger Boughtons recording, which I am sure is a
million times better than mine, I will point out that after making my
recording in 1988, I asked "everyone" that I met about this low freq.
sound (I wouldn't be surprised if I asked you too...) but no one had
ever heard of it, or recorded it. This is very surprising, indeed, as
the Capercaillie is one of the "cult" birds in Sweden, which every
nature recordist should record at least once a year, to be
"somebody". Still, nobody would step forward and tell that he knew
about any low freq. sound.
How many times have I seen Capercaillie on TV? Many times. Not once
with the "burr"!
So I did my best to tell everybody and spread my "finding," just to
get funny looks. Now, it seems, at least a few birders know about it.
With respect to Roger Boughtons recording, I would say that there
ought to be at least hundreds of Swedish recordings of Capercaillie,
much better than mine and probably better than Roger's too.
But, as far as I knew, until now, not one of them have any low freq.
material! So, I was kind of proud about my recording! Even though it
is a poor recording, as a whole, it does have the "burr"!
I am soooo sorry that you fantastic guys at the Royal Fancy British
Library has known about this low freq. sound all the time and have
the most fantastic recording of it already.
Sorry to bother you.
Klas.
At 01:10 2013-05-16, you wrote:
>Hi Chris, I'm afraid I don't have access to a PDF - the article is in
>copyright to Wiley and can be purchased from here:
>INFRASONIC COMPONENTS IN THE SONG OF THE CAPERCAILLIE TETRAO UROGALLUS
>http://onlinelibrary.wiley.com/doi/10.1111/j.1474-919X.1979.tb05021.x/abst=
ract
>Ibis Volume 121, Issue 1, pages 95-97, January 1979
>
>However, from memory, this bird emits true infrasound, i.e. components bel=
ow
>20Hz, well below the cassowary example (although maybe this is just a case
>of needing better gear - the cassowary is a bigger beast and might be able
>to produce lower frequencies). The sound spreads into the audible range,
>above 20Hz, which is what we humans hear. The best recordings of
>Capercaillie I've ever heard were made by Roger Boughton in Scotland, usin=
g
>a Sennheiser MKH105 or MK110, a 'military' spec mike that can capture just=
a
>few Hz. With all respect to Klas, his recording just does not compare.
>Forget about using a parabola to record these birds properly: the lower th=
e
>frequency, the longer the wavelength, and by the simple physics of
>diffraction and reflection you can calculate that to capture 20Hz, the
>reflector needs to be at least 56 feet in diameter - instead use a decent
>open mic and place it close up - takes many hours of fieldcraft but the
>results stand the test of time.
>
>Richard Ranft
>The British Library
>London
>
>
>
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