I've been borrowing a lot of CD's and DVD's from the library lately, including many thru the
system-wide reserve and hold system. Some have been very heavily used, and some are lent and moved
around in damaged or flimsy packaging. Others are just plain old -- original-vintage CD's from the
mid and late 1980's. Surprisingly, I have not had any errors or misplays. I've also analyzed a few
of the CD's using the Plextor tools, to see how they scan despite numerous scratches. All have been
within acceptable error rates.
Now, one precaution I take is to clean each disc with isopropynol and a lens cloth, wiping in
circles very gently. There are numerous fingerprints on them and we have discussed that in many
cases, fingerprints stymie error-correction that can "see" through numerous scratches.
I have not had such good luck with dye-burned CD media. I have found it's OK with a few scratches
but heat, like what's in a car, just won't do over time. One summer usually does in a CDR. Since
they cost next to nothing, I don't care. But they are certainly not hearty like stamped/manufactured
The big surprise was how well DVD's hold up. The invariably get mauled, for some reason -- I'm
thinking the average DVD user is just not atuned to being as careful as a music fan (and they seem
to have super-grubby fingers).
All in all, this laser technology turns out to be pretty robust -- which is self-evident since it's
lasted all these years.
I'm not suggesting people be less careful, or make fewer backups, or have a looser backup strategy.
I'm just saying that CD's and DVD's are surprisingly non-fragile. And, it sure is a relief to get a
CD with scratches that still plays well and sounds just fine, vs a scratched-to-hell LP that might
have had just a few spins on a lousy setup.
Alas, my librarian told me that the county-wide system is studying an online music model that would
be essentially a mass subscription to something like Yahoo or Real's "broadcast" streaming MO.
Great -- a CD can be 20 years old and scratched and STILL sound far better than a digi-swishy
compressed crapola streaming format. Plus, the CD's have the booklets, no small matter to those of
us who actually might want to know some details (ie want some information, the business of a
library). I'm hoping economics dictate a status quo for the foreseeable.
-- Tom Fine