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From: jlg@lanl.ARPA
Newsgroups: net.audio
Subject: Re: Floating Point CD's
Message-ID: <15637@lanl.ARPA>
Date: Tue, 6-Nov-84 17:05:32 EST
Article-I.D.: lanl.15637
Posted: Tue Nov  6 17:05:32 1984
Date-Received: Thu, 8-Nov-84 19:15:39 EST
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> There is a floating point format known as FOCUS developed by a grad student
> at the University of Oklahoma. It was designed for electronic sampling
> instrumentation, and avoids the "hole around zero" problem with normal
> floating point representations. Perhaps this would be a better choice than
> either a normal floating point or integer representation?
> 
> I don't have the article anywhere near me, but will gladly dig it out for
> anyone sending mail asking about it.
> 
> 	<mike

If I remember to FOCUS design correctly, it used a scheme for varying the 
size of the exponent field to prevent underflow (or overflow for that matter).
Unfortunately, this required the use of more exponent bits to begin with, 
thus making the significand smaller.  The 'hole around zero' is not much
of a problem for audio purposes since a signal that small would be
120 to 150 DB below the maximum representable signal (maybe more, depending
on which floating point format you chose to use).  This would probably
be below the threshold of hearing for any reasonable volume level.