Got CD Rot? You'd Best Check Your Collection

by , 9:00 AM EDT, May 6th, 2004

Vinyl produces a warm sound, but CDs are immortal, or so we were led to believe: Barring fire, teething babies, and aunts who mistake you favorite CD for a newfangled hot pad, CDs are suppose to last a lifetime with minimum care as compared to vinyl records.

Movies have benefitted from the technology behind CDs as well; not only are movies now packed with extra feature extra features to give any Gene Shallot wannabe a lifetime of happiness, DVDs take up far less room on your bookshelf.

What if someone told you that your prized music or movie collection was subject to a malady that produces the same affects in your digital discs as those unfortunate oldsters with Alzheimer's Disease? After investing hundreds, maybe even thousands of dollars on music or videos, you'd be a bit concerned.

eWeek is reporting that you may have reason to start nail-biting; some CDs and DVD are vulnerable to what is being called "CD Rot" by some experts. According to the article, the rot occurs when air manages to penetrate the thin layer on the top (label) side of a CD or DVD that is supposed to protect the aluminum on which the digital data is actually stored. The air causes the aluminum to oxidize, and you lose data. From the article:Here's a excerpt from the eWeek article, CDs and DVDs Not So Immortal After All

"We were all told that CDs were well-nigh indestructible when they were introduced in the mid '80s," (Dan) Koster says. "Companies used that in part to justify the higher price of CDs as well."

He went through his collection and found that 15 percent to 20 percent of the discs, most of which were produced in the '80s, were "rotted" to some extent.

The rotting can be due to poor manufacturing, according to Jerry Hartke, who runs Media Sciences Inc., a Marlborough, Mass., laboratory that tests CDs.

The aluminum layer that reflects the light of the player's laser is separated from the CD label by a thin layer of lacquer. If the manufacturer applied the lacquer improperly, air can penetrate to oxidize the aluminum, eating it up much like iron rusts in air.

But in Hartke's view, it's more common that discs are rendered unreadable by poor handling by the owner.

"If people treat these discs rather harshly, or stack them, or allow them to rub against each other, this very fragile protective layer can be disturbed, allowing the atmosphere to interact with that aluminum," he says.

There's much more information in the full, and rather interesting article, at eWeek.

The Mac Observer Spin:

Makes you wonder if vinyl was so bad after all; at least with vinyl you knew that your music was vulnerable to everything from dust to gravity. You knew what you were getting into and treated your music collection accordingly. CDs, on the other hand, were billed as being nearly as indestructible as the cockroach: An exaggeration, perhaps, but you get the idea.

What a surprise to learn that CDs has its Kryptonite.

Now that we know, will we take better care of our music collection? A few will, but most probably won't, not when you can just buy another CD, or download the music you want from virtual places like the iTunes Music Store. Still, it's good information to know once you've discovered that the Fleetwood Mac CD you bought 15 years ago starts getting the jitters.

CDs and DVDs Not So Immortal After All