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From: gray@moose.unidyn.com ()
Subject: Re: Acoustic echo cancellation
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Date: Mon, 1 May 1995 23:12:45 GMT
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Jim Stratman (JAStratman@koaspc1a.delcoelect.com) wrote:

: SigTech out of Cambridge, MA makes a unit that does echo cancellation.  It works quite
: well as long as your head is in a vise.  I also hear that Snell has a unit that works with one of their
: speakers.

The earliest versions of SigTech's system, which I did at Acoustic
Research (AR), would work best if your head was in a vise, but I don't
think the current one requires this.  Have you tried it?  The trick is 
not to try to produce phase-coherent echo cancelling when the wavelengths 
are smaller than your head.  I haven't heard the system in a couple of 
years, now, but it's in use in many professional studios, including Abbey 
Road.

I hear that Snell once demoed their system, but, since their hardware
wasn't ready, they used SigTech's, hidden under the table. 

You can reach SigTech at 617-491-8890.
--

Gray Abbott (gabbott@tpoint.net)	    "Everything's real here.  Many
Sofgry Systems				      people are surprised."
Scientific & Engineering Software           Mr. Edwards, The Sword in the Stone
