Durability of CD-Rs?

[DaveM]

Last night while digging through my CD collection, I came across some CD-Rs containing music compilations done for me by a friend in 1999-2000. On playing one for the first time in well over a year, I was astonished to discover that the sound was distorted and there was a lot of background noise. I could not help but recall the sound of a scratchy record.

This CD has been stored in the same area as the rest of my collection and is the same brand of media as any number of other disks that I have. I have yet to discover any others that have apparently "degraded" as this one has.

Has anyone else had any experience with CD-Rs "going bad"? And can it be prevented in any way? I've never expected them to be an archival-quality medium, but was nonetheless surprised to discover that this disk had lost so much of its sound quality.

[RedjackRyan]

I haven't noticed any appreciable degradation on any of my cd-r's (data) I have noticed that they are very easily scratched however. I did a quick google and found this article... It is a bit on the technical side so you might want to wrap your head in duct tape before reading, to prevent any exploding skulls.

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Exposure to radiation, inks, other chemicals, water, or pollutants can adversely affect CD-R quality. Although environmental degradation should be avoided, a major cause of deterioration is improper user handling based upon overconfidence in the robust construction and error correction of CD-R media. Handling or storage conditions may degrade good discs, especially if the thin, vulnerable protective coating on the label surface is flawed or damaged. In addition, high quality media that is recorded in poor writers may fail interchange standards. Such issues are outside the scope of this study that is focussed on the longevity of media that has been properly recorded and handled.

CD-R discs normally contain four layers consisting of a pre-grooved substrate, a dye layer, a metal layer, and a protective coating. All but the metal layer contain organic compounds that can degrade as a result of changes in their chemical structures or because of unstable defects that grow in size. Mechanical stress induced by rapid environmental changes may result in excessive differential expansion of the various layers and delamination or excessive birefringence. These and other ageing modes limit media longevity.

CD-R ageing processes can be accelerated by high temperature and humidity environments. Media manufacturers may estimate longevity by evaluating discs aged at elevated temperatures and humidities. Extrapolation to ambient conditions, typically 21 C-23 C and 15%-60% RH, then provide a lifetime for the product. Such methods are valid only when a proper end-of-life criteria is applied. BLER is commonly used for this purpose, although supporting evidence has not been published. Some vendors have used a maximum BLER of 50 per sec. to determine end-of-life. Standards ISO/IEC 10149, ANSI/NAPM IT9.21-1996, and others use a BLER limit of 220 per sec. Draft Standard ISO/DIS 12024 required zero E22 and E32 errors in addition to BLER limits.
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http://www.mscience.com/longev.html

Additional information at: http://www.clir.org/PUBS/reports/pub121/sec4.html

[DaveM]

Reaching for that duct tape now....along with my tin foil hat.

[Wildflower Fever]

DaveM, I don't think any CD-R's are infallable, but some brands seem to last longer than others. I generally have about 50 Mix CD's in my vehicle at all times, and burn discs regularily. Of course, our lovely MN weather as you know can really test the durability of these discs. They get abused, and are always in my vehicle, and I've noticed a few things, although unscientific, about certain brands/styles. This is only an observation, of course, but I prefer TDK after trying them along with Maxell, Fuji, and many others. Also, oddly enough, discs with a color (white, yellow, blue or any) seem to last longer than the ones that appear silver or translucent. THis may also be because I write on them with a sharpie. The net result is that many of the TDK's (white surface with up to 48x sampling) are still sounding great after up to 5 years, and the silver ones (mostly maxell and fuji) tend to scratch easier, and sound degrades sometimes in as little as a few weeks. Again, I'm not qualified in any other way than being a "busy CD customer", and I know what brands/styles i'm going to stick with. Hope this helped a little.