Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Posting-Version: version B 2.10.1 6/24/83; site brl-tgr.ARPA Path: utzoo!watmath!clyde!burl!ulysses!mhuxj!ihnp4!zehntel!hplabs!intelca!qantel!dual!amd!decwrl!decvax!genrad!wjh12!harvard!seismo!brl-tgr!wmartin From: wmartin@brl-tgr.ARPA (Will Martin ) Newsgroups: net.audio Subject: Re: Vinyl vs. CD recordings Message-ID: <4758@brl-tgr.ARPA> Date: Thu, 20-Sep-84 11:45:27 EDT Article-I.D.: brl-tgr.4758 Posted: Thu Sep 20 11:45:27 1984 Date-Received: Wed, 26-Sep-84 05:49:07 EDT References: <3050@watcgl.UUCP> <61@unc.UUCP>, <829@opus.UUCP> Organization: Ballistics Research Lab Lines: 36 With regard to the continuing CD vs. analog vinyl discussion: Is it so inconceivable that a purely analog yet non-contact laser playback system could be devised for existing vinyl LP (and maybe other) discs? Of course it isn't a trivial problem, but, then, neither was color TV or integrated circuits. It's essentially an engineering problem -- detect the reflections from a groove of laser light, while tracking the spiral, ignoring spurious signals from random reflections or dirt and dust, etc. I would think that this could be done in a totally analog manner (whether it WOULD be so done is another question, though -- it would probably be easier/cheaper to do it by digital conversion, and all the engineers are digital-mad these days; you can hardly find an analog design article in the magazines anymore). If it was done in pure analog, though, all the anti-digital arguments are overcome, while all the reasons for digital are also achieved (except for the minor one of the size of the storage medium; LPs are still bigger than CDs). However, this gives you the best of both worlds. The existing worldwide inventory becomes playable on the new equipment, yet doesn't wear as it is played. I would think that a sophisticated design would let the user "tune" the position of the groove walls that is being "played" (independently, too -- infinite channel separation) to track the undamaged (or least-damaged) section. Media granularity could be "tuned out" -- we could hear old 78's with no suface noise, yet capture whatever acoustic signal that the shellac still holds, etc. At first, such equipment would be expensive, of course, and would be used for making tape copies of older recordings; it should drift down in price like everything else, though, so that it would eventually be something an individual could afford. So let's see some engineers get into this -- people at various installations on the net that read this: post this on your engineers' bulletin boards. Let's get an "AD" system built ("Analog Disc")! Will Martin