How long will CD-R's & DVD-R's last?

Several days ago a thread was posted, in which the discussion was about how to copy tapes to cd. One of the responders, in a passing comment, mentioned that cd-r's would only last 10 years. This got me to wondering, is this scientific fact, or "audio wives's tales"? I'd be interested to hear about the longevity of recordable media from folks who are in the know on this subject.
They do deteriorate. It also applies to regular CDs as well as the recordable CDs. It is my understanding that deterioration is primarily due to poor quality construction of the CD itself. Some will last longer than others depending upon how well it was made and what materials were used. If you search the archives, you'll find some previous threads on this topic.
I've heard the same finite longevity theories, but have yet to hear of a confirmed failure. That does not mean it's not true. I'm a commercial photographer and I do store much of my work on CD and DVD media, so the issue does concern me.

On a related note there is some interesting data about DVD media quality. Most of the big manufacturers that you buy at OfficeMax/Depot/Staples, etc. are rebranding, or rather buying cheap media out of Taiwan. It is particularly annoying with some DVD-R/RW media that consistently fail to burn. There is some good information about locating quality media here, which will refer you to a link to download freeware that will help identify the media you are using. I won't go further as the site can explain it far better than I.

FWIW, I've heard that the Library of Congress still archives recorded material on good old analog vinyl!
I have read in one report that claims DVD+/-R will only last as short as 2~3 years. when I told my friends and we are all engineers and one of them used to work for a lazer diode company that read/write DVD, no one believed me. but it got me worried and I did archive more often now since media is so cheap.
There are archival quality CD-R's and DVD-R's.

These discs from Mitsui have a life expectancy claim of 100 years because of the 24K gold reflective surface. Even if they are wrong by 50%, 50 years should be enough for most things.

Regards, Rich
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I just hold in my hands HP 650MB CD-R that I burned in early 1998. It is almost 9 years old and sounds fabulous. I also have many DVD+R disks burned more than 3-4 years back. Every disk is like new.
These are the Disc made in Japan. Maxell and Sony made by Taiyo Yuden.

You can no longer be certain that media from Maxell and Sony is genuine Taiyo Yuden media (definitely an excelent manufacturer). I've bought Sony DVD media that I discovered was of the worst quality manufacturing and was made in Taiwan. More than half of them would not burn and ended up in the circular file (pun intended). I think more and more the larger manufacturers are shopping for the best price and not necessarily the best media. I've recently started buying media from Supermedia Store where you can buy unbranded Taiyo Yuden media, as well as having other good media selection.

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Marco I was hoping you would address my comment on demagnetizing a CD-R audio disk after recording on it. Why would spinning it in my Bedini Clarifier degrade the sound? Any thoughts....

I've never thought to even try that. I stopped using my Bedini a while ago when I moved and put it in storage. I'll see if I can find it and give it a try. Interesting observation though. No idea what's going on except to say that the recordable media is different from the factory media. Perhaps the explanation for your results lie in that difference. Is it only true right after you burn the CD, or does it hold true to any CD-R/RW at any time after it has been burned?

I have had them fail.. This was not due to just useage or age, but Burned discs will make it about 2 years if in environmental conditions.. I had several in the car, from 2 winters and 2 summers, they will become very problematic, regardless of what media.. Standard CD from the store have sat in the car 10 years without failure, now of course I am sure any direct sunlight could quickly change that, but its pretty much a guarantee it will occur on CDR just from temp changes and moisture I belive. Something happens either they de-laminate, or All of a sudden posses increased amounts of Jitter and or Warp in the disc itself, they will develop skips, and sometimes not even read after a while even if protected from direct sunlight I have experienced, but for 20 cents a disc, I could care less than having a 20 dollar cd get tossed around and scuffed up in the car. However I can not comment on kept in a environment controled area like the home, they might be okay.
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I was a poster in the original thread refered to by the creator of this thread. I did point out that commercially produced CDs use a stamped foil layer where CD-R/RWs use an ink layer. That is why commercially duplicated CDs outlast CD-R/RWs. Supermediastore is a great source for blank media and accessiories. I had horrible results with Maxell CD-Rs, and have had to burn copies of all of them onto other brands of CD-Rs in order to get my CD players to read them properly. My best results, both with a computer burner and a stand alone recorder, have been with CD-Rs from Taiyo Yuden, Fuji and Phillips. Oddly, Mitsui CD-Rs worked perfectly on my computer and on a Pioneer CD recorder, but had a roughly 30% failure rate on my Marantz CDR-632 recorder. I will again recommend that either the analog source be retained, or that you copy to a fresh CD-R every few years. It takes a few minutes and costs 20 - 50 cents, depending on the media. Remember to date your CD-Rs!