Midnight Oil

[Powderworks] CD-R's dying

Maurice R. Kelly mkelly@deadheart.org.uk
Mon, 24 Feb 2003 10:09:31 +0000 (GMT)

On Feb 23, Jacques Cuneo wrote:

> Typical CDs and DVDs will *not* oxidize and die.  CD-Rs are a different
> animal because they use a dye of sorts to achieve the readable pattern.

I think it's a vegetable based dye - I presume it's organic nature is what
causes it to break down.

> Commercial CDs and DVDs are made using stamped aluminum.  All aluminum is
> already oxidized, per se.  Aluminum is one of those metals that actually
> oxidizes so quickly is forms a protective layer over itself (conversely,
> iron's problem is that is oxidizes slowly, allowing for oxygen to continue
> to get in).  Some early CDs had have some polymer problems or problems with
> adhesion of polymer to aluminum.  Those problems have long been solved.
> Unless you get unlucky and get a defective CD or DVD, those should last a
> lifetime.

I read a recent article (somehwere, can't bloody remember where now) which
suggested that 10% of DVDs will decompose. It cited a few specific DVDs
which people have reported as already decomposing.

That said, it's hard to know what to believe about these things any more.
They tell us that these things will outlive us if handled carefully. Who
knows really. Personally I've started making copies of all my CDs. It's
also better for when I leave them in the car - at least thieves can only
steal a copy. Backing up all those Oils CDs is going to cost a bit though!

To make this a bit more Oilsy though, I should mention the fact that one
of my Oils discs is no longer playable. It was a Cd-single featuring The
Dead Heart (Extended Version) which I think I bought off Ebay. I have
played the disc about 3 or 4 times. Was recently going to make better MP3s
from it, and found it virtually unreadable. It won't play in a standard CD
player or a CD-ROM drive, and I could just about get MusicMatch Jukebox to
rip it at between 0.1x and 0.2x. Which took I think 40 minutes or so to
rip one song!

Inspecting the surface of the disc I see no problems. There are no
scratches, no fingerprints, and no dirt on the surface. The only anomaly
with this disc is that I can see through it. It is possible to read the
printed text on the label looking through the playing side. And I don't
mean by holding it up to a light! My theory is that the reflective surface
is too thin, and some of the laser light is actually passing through the
disc rather than reflecting off it.

It's a UK CBS release (if memory serves me correct.) Can anyone else
report something similar.

Maurice R. Kelly