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Path: utzoo!decvax!ittatc!dcdwest!sdcsvax!bmcg!bprice
From: bprice@bmcg.UUCP (Bill Price)
Newsgroups: net.audio
Subject: Re: Print-thru: Magnetic or Mechanical (stereo recording)
Message-ID: <2011@bmcg.UUCP>
Date: Tue, 26-Nov-85 16:51:14 EST
Article-I.D.: bmcg.2011
Posted: Tue Nov 26 16:51:14 1985
Date-Received: Wed, 27-Nov-85 22:18:36 EST
References: <937@cvl.UUCP> <2860@wateng.UUCP> <428@nicmad.UUCP> <2869@wateng.UUCP>
Reply-To: bprice@bmcg.UUCP (Bill Price)
Distribution: na
Organization: Burroughs Corp. ASG, San Diego, CA.
Lines: 34

gtward@wateng.UUCP (Greg Ward) stands himself corrected, but...:
>> >                                                       In fact, how the
>> >two channels are multiplexed in the groove is that one channel is
>> >recorded in the side to side variations of the groove, and the other is
>> >recorded in the up and down variations.
>> 
>> Sorry, but the gentleman you are referring to was correct.  On record,
>> each wall DOES pertain to a certain channel.
>> Mr. Video   {seismo!uwvax|decvax|ihnp4}!nicmad!brown
>However I would like to defend myself by saying that I did not make up
>my version of how the two channels are recorded in the groove, I read
>it somewhere. This was a number of years ago, and I cannot remember where
>I read it, so I haven't been able to look it up.
>                         Greg Ward

Greg, it's quite likely that you did read it somewhere, long ago.  In the
very early days of stereo, both techniques were used: the
horizontal/vertical modulation was done first (i think), but it wasn't
compatible with the prior art--monophonic.  Then, someone came up with
"Compatible Stereo", wherein the horizontal modulation was L+R (=mono), and
the vertical was L-R.  Doing the arithmetic, you'll discover that this
"Compatible Stereo" scheme is exactly equivalent to (what was then called)
"45/45 [degree]" modulation, or diagonal encoding.

I don't have any records (any more) of the H/V encoding, but some of my
mid-50 oldies are labelled "COMPATIBLE STEREO".

Ain't it funny, how the L+R/L-R mono-compatibility trick gets around?
LP's, FM, AM, TV, ...

--Bill Price
-- 
--Bill Price  uucp:  {Most Anybody}!sdcsvax!bmcg!bprice
              arpa:? sdcsvax!bmcg!bprice@nosc