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Re: Miniature Pseudo-SASS Array

Subject: Re: Miniature Pseudo-SASS Array
From: "Avocet" madl74
Date: Sat Aug 11, 2012 6:15 am ((PDT))
> The recording I posted didn't show it, but the mini-SASS, as it is
> right now, exhibits some serious stereo imaging issues. It would
> take some effort to get those problems resolved

Curt,

There is some theory to think about with a redesign. The mini-SASS,
the SASS, the Jecklin and anything that separates two omni mics is
basically a dummy head, and as such will give its best results with
binaural listening. The standard SASS is a dummy head with a big nose,
and if it works, use it.

A point to ponder on any "dummy head" design is the time difference it
produces between the mics for sounds at an angle. These don't have to
match our own heads if you want a different image angle for a given
object angle. It's like using different camera lenses.

Next point, with low frequencies, you won't get a good stereo
resolution when the wavelength is greater than the mic rig dimensions.
As a reference, 100Hz has a wavelength of 340mm or about a foot. To
get comparable results to sounds at 200Hz as against sources at
1000Hz, you would need dimensions five times greater in theory.

Now someone tell me how you can hear the direction of a 200Hz sound,
with wavelength 1.7met, with your ears at 170mm apart, and you will 
know how our own ears hear stereo. :-)

David

David Brinicombe
North Devon, UK
Cogito cogito ergo cogito sum - Ambrose Bierce







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