How reliable are home-grown CD recordings?
Short answer - not very!
Some important questions have been raised recently on https://thesession.org/recordings/2551/ concerning the longevity, or otherwise, of CD recordings, specifically “home-grown” CD recordings which may be available commercially. It’s useful to have these things aired in the Discussions forum.
The home-grown CD is usually burned by the process we use on home computers – a dye structure within the CD is modified by a laser beam to give the recording. A commercial CD from a reputable source (as most are) will be pressed, in an analogous manner to the pressing of vinyl LPs, so as to give billions of ultra-microscopic indentations in the surface of the CD which can then be read by a laser beam. The pressed CD is inherently more reliable than the dye-based article.
The thing to do with a "home-grown" CD, if its one you want to keep, is to back it up immediately to a computer hard disk. In fact, it’s not a bad idea to keep an external hard drive specifically for archiving audio and video, and nothing else. If that’s all you’re going to use it for, you’ll be switching it on comparatively rarely, and the rest of the time you can safely keep it in a cupboard. A hard drive that is looked after like that and is little-used can be expected to last a very long time, much longer than a home-grown CD.
If you have acquired a home-grown CD that has a stuck-on label - perhaps any label - then that is Baaaad News! The chemicals in the label will attack the dyes in the home-grown CD and it will fail within a couple of years, or less. I know, I had it happen to me some years ago.
Another point about home-grown CDs: There is no guarantee that the CD recording will have been verified (i.e. compared digitally with the original) after it has been burned. (In fact, if I were a betting man I’d take bets that such verifications are rare events!) If it hasn’t been verified then there is an excellent chance that a track may have bit-level errors that will cause drop-outs or even a complete failure of the track.
Moral: if you burn your own CDs or DVDs, always instruct the program that does the burning to do a verification – it will take a few minutes longer, but it’s worth it. Make sure the contents of the CD/DVD are backed up on your computer. Store your home-grown CDs and DVDs in a cool, dark, dry place, and periodically check them for digital integrity. If a CD starts to deteriorate (as it surely will in time) then of course you’ll have a backup available on a hard drive, won’t you? 🙂
On the occasions when someone gives me a home-grown CD I check it out first with software. I use the free-licence “CDCheck” program for this. This saves the CD onto my computer during the check , and if there are any bit-level errors, will try to mend them on the hard drive as the CD is being saved.
Oh, and don’t use re-writable CDs for stuff you want to keep – use the best quality single-write CDs you can lay your hands on (they’re usually made by well-known and established manufacturers.) I’d avoid the cheap anonymous stuff sold in non-specialist stores. Buy from someone who has a reputation to lose.