A response to the query about the lifetime of CDs. Yes,
there are some CDs that have deteriorated in a short time, and in
fact Polygram is a prime culprit. This has gone so far as to have
programs to replace certain CDs and CD sets that have gone west.
On the other hand, most CDs (if handled reasonably) are very sturdy.
I attended the Association of Recorded Sound Archives meeting here in
Nashville about two months ago and there was a session on media
suitable for archiving. Included in the discussion were remastering
gurus and professional sound librarians (from Library of Congress,
Edison site, Sony/Columbia etc). The following opinions were
expressed:
(1) Tapes are fragile. Ironically, the medium used most for
commercial mastering of CDs, 3/4" U-matic, is the most fragile. At
present Sony/Columbia is redubbing their material from the 80's
_first_ because it is going sour so quickly. DATs are also fragile.
Any flaw in the tape tends to ruin the entire tape. The best digital
tape medium for archiving is the NAGRA format and a SONY-developed
proprietary format. Analog tapes can have a life of 30 years or so,
but proper storage is very tricky. The analog tapes of recent
manufacture can shed oxide within five years.
(2) The consensus was that writable CD-rom was the best compromise
for archiving information at a reasonable level of quality. Industry
estimates of its effective lifetime run about 50 years.
(3) Some of the attendees at the meeting commented on the reasonable
reproduction quality of shellac 78 rpm records, many of which are
reaching their century. We were also privileged to listen to a
(recently made) tape of a Handel oratorio taken from a brown wax
cylinder recorded in the Royal Albert Hall in 1886. This is thought
to be the first music recording ever made. Kinda scratchy, but it's
all there....
A. B. Bonds
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