From jerry Mon Aug  8 10:19:03 1994
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Date: Mon, 8 Aug 1994 10:19:02 -0400
From: Jerry <jerry>
Message-Id: <199408081419.KAA26719@nick.csh.rit.edu>
To: pat, jerry
Subject: Decoding Center CHannel
Status: O

  
  I think I figured it out...

let A be the encoded  Left channel  (L+C)
Let B be the encoded Right channel  (R+C)

sum the 2 together,,

A+B = (L+R+2C)

now subtract the 2
  A-B
(L+C)-(R+C)
L+C-R-C
 L-R

then subtract the two..

L+R+2C-(L-R)
L+R+2C-L+R
  2R+2C


nevermind


From pat Mon Aug  8 11:28:10 1994
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To: Jerry <jerry@nick.csh.rit.edu>
Subject: Re: Decoding Center CHannel 
In-reply-to: Your message of "Mon, 08 Aug 1994 10:19:02 EDT."             <199408081419.KAA26719@nick.csh.rit.edu> 
Reply-To: pat@mail.csh.rit.edu
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Date: Mon, 08 Aug 1994 11:28:05 -0400
From: Pat Fleckenstein <pat@nick.csh.rit.edu>
Status: O

    You said the center channel was at -3db from the Real Center
	c == center encoded
	C == center actual

	-3 db = 10 * log c/C
	-3/10 = log c/C
	10 ** (-3/10) = c/C
	1 / 2 ~= c/C
	C ~= 2c

In <199408081419.KAA26719@nick.csh.rit.edu>, you mailed me to say:
>let A be the encoded  Left channel  (L+C)
>Let B be the encoded Right channel  (R+C)

    So these assumptions should be....

	A = L+c = L + C/2
	B = R+c = R + C/2
    
    This still doesn't get you anywhere... it's still three unknowns
    and only two equations.

    As an interesting point... the definition of decibels is...
    10 * log of the ratio of two powers.  So... the fact that your
    amp goes from -40db to 0db means that it goes from a ratio of
    10 ** -4 to a ratio of 1.  Now... I don't have any clue what
    these numbers would be.  Since 0db is louder than -40db on your
    stereo... I would say that it must be the ratio of current output
    to maximum output.  Odd to say the least.  It would be simpler
    to number from 1 to 10.  8^).  If I were measuring decibels on
    a stereo... I'd go for the ratio of output to input... in which
    case, -40db would be real-damn faint.

    alter,
    pat