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Re: [Bulk] [Nature Recordists] Re: The lowest frequency sound know f

Subject: Re: [Bulk] [Nature Recordists] Re: The lowest frequency sound know f
From: "Dan Dugan" dandugan_1999
Date: Wed May 15, 2013 7:53 pm ((PDT))
> Forget about using a parabola to record these birds properly: the lower t=
he
> 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 -

It needs to be that big to directionally amplify 20Hz, but that doesn't mea=
n it can't capture 20Hz.

> instead use a decent
> open mic and place it close up - takes many hours of fieldcraft but the
> results stand the test of time.

I agree, an omni mic close to the source can't be beat. But then, lower fre=
quencies travel extraordinary distances, as utilized by elephants, for exam=
ple, so detecting low frequency sounds doesn't require a close microphone.

-Dan








"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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