From: smee@bristol.ac.uk (Paul Smee)
Newsgroups: rec.audio
Subject: Re: Why switch to CD?
Date: 6 Oct 92 09:25:24 GMT
Reply-To: P.Smee@bristol.ac.uk (Paul Smee)
Organization: University of Bristol

In article <1992Oct6.064803.25275@news.cs.brandeis.edu> jacob@max.cc.brandeis.edu ( ) writes:
>just a piece of trivia: some mentioned the advantage the CD has over
>a the LP in term of durability. well, i read a few years ago
>in the boston phoenix quarterly (?) electronics supplement there existed
>a "laser turntable" that reads (only black) vinyl LPs with a laser beam.
>of course you can still melt your LPs in the oven if you wish but you can
>do pretty nasty things to you CDs also if you want. the point is a "laser
>turntable" doesn't put an LP to more wear than a CD player does a CD.
>also given that the "laser turntable" reads the depth of the groove optically,
>conceivably one could imagine a coating process whereby you could have your
>LPs layered with a transparent layer of something that would forever render
>them immune to dust as well. the only problem is, according to the boston
>phoenix, the laser turntable exists, its r&d is completed but it is not
>in production.

I'm led to believe that they can be bought, if you've got lotsa money
-- but I don't have a clue where.  The problem (which you allude to) is
that they can't tell the difference between a 'bump' caused by the fact
that the groove wall undulates (i.e. desireable sound) and a 'bump'
caused by a microscopic particle of dust in the groove, so that you
have got to have virtually a surgical (or micro-chip production)
quality clean room in order to use one successfully.  (Maybe your
'coating' idea would help keep the grooves themselves clean, but you
still have to keep dust from settling on the surface while the thing is
playing.)

Given both the cost, and the inconvenience, I'd just about bet that the
market will be restricted to companies trying to migrate really old
records (out of print and masters no longer exist) to more modern media.
And, if that's right, I'd just about bet they'll process them to remove
other noise artifacts, and so probably digitise them on the way through,
which sort of defeats the purpose of the whole thing.

There was another short article about LP lifetime in the papers here a
few weeks ago, but unfortunately I didn't manage to save it before the
paper got pitched, so can't recall details.  Keep expecting some hi-fi
mag to pick up on it, though.  Was to the effect that some institution
or another, which as part of its function keeps archives of recordings,
has found that after some (frighteningly small) number of years, all
the plasticisers vanish from 'modern' vinyl, and the stuff essentially
depolymerises itself and 'falls apart'.  (They are trying to develop
'heroic' storage and rescue methods to preserve their collection.  The
number of years was significantly smaller than a lifetime, but
unfortunately I can't remember it.)

If any UK reader wants to try to dig out the article, it was in one of 
the Guardian or the Observer, and between 27 August and 1 September
(inclusive), this year.  Probably the Observer on the Sunday in the
middle of that period.  I don't have time to do a library search myself.

-- 
Paul Smee, Computing Service, University of Bristol, Bristol BS8 1UD, UK
 P.Smee@bristol.ac.uk - ..!uunet!uknet!bsmail!p.smee - Tel +44 272 303132