What is the life of a CD ?

[ted]

It seems a simple question but I have never seen any discussion about it. Perhaps nobody can tell as yet because they are too recent a medium. Tape recordings tend to get a bit fuzzy after about twenty-five years, or so I have found. Mind you, neither the tapes nor the recording equipment were very good, so that might be just me.

I have heard that commercially pressed CDs might last longer than ones made on recording equipment but is this really so I wonder ? Does anybody know as yet how durable CD recordings are ?

What then would be the correct strategy to preserve recordings indefinitely in some form ? In the absence of any solid information I have decided to keep multiple copies of tapes, audio CDs and CDs of mp3s, and make new copies of the latter two every few years.

Is this reasonable ? You see, I don't want to reach, in twenty years time, a point I did with my tapes, where I want to listen to something I recorded now and suddenly find annoying deterioration has occurred or, worse still, the medium is unplayable.

[thalbergmad]

Very interesting question Ted.

My Dire Straits CD (1986 I think) is still going fine the last time I checked and it has seen a bit of use. On the other hand, tapes of a similar age have not fared so well.

I am no expert, but i think that the reading of a CD does not actually cause any damage, whereas eventually the data held on a tape will wear off.

I too am going to store my tapes on a CD, as i do not want to lose years of collecting.

Some of my old 78's sound great after 70 years, especially with a bamboo needle.

When my Auntie died, she left me a huge collection, of 78's, a couple of which are old Waller recordings. Can't wait to give them a spin.

[bearzinthehood]

However, certain burned media starts to peel after a certain amount of time.  Pressed CDs don't seem to have that problem, although I've seen a few shatter as a result of being pulled out of a jewel case.

[Waldszenen]

I've never had this happen to me before, but apparently all CDs (burnt or pressed) become more brittle over time and if the case you're using happens to be one of those tight-click ones (like the double-case ones they use for DG), you might end up warping the disc altogether.

Also, burnt CDs will probably have a shorter lifespan than pressed CDs due to something happening to the dyes over time.

[timothy42b]

This is a really good question.

You have the problem of degradation of the information caused by playing.  LPs can only be played a maximum of 30 times before the wear from the mechanical contact causes the quality to be unacceptable.  Tape rubs across rollers and capstans, etc., and loses the oxide coating over time, though the expensive metal tapes seem to be better.  CD should in theory not degrade at all as the only contact is the laser.

But CDs are apparently susceptible to that bacterial growth problem, and of course they get scratched and warped and start to skip. 

You have the problem of information access.  How many of us can still read an 8 inch floppy?  A 5.25 inch?  even a 3.5 inch?  How many can still read a Harvard Graphics 1.0 format file?  Or something in vi?  What about a beta VHS tape of our favorite performance?  Nobody knows what the future brings but it is changing fast.  For that matter, a lot of us no longer have a turntable. 

Recently I made a CD for music for a church service.  After I burned .wav files to it, I verified I had done it correctly.  I also got to church early, set up, and played each piece to check it again.  During the service, some files did not play - this CD had already self destructed.  I don't have any idea what caused that or how to prevent it.  My kids think I left it on Pause for too long instead of Stop. 

[Bob]

No storage medium last forever.  CDs will break down in time.  You have to keep transferring media in order to keep it.  Nothing will last forever, but if it's more than your lifetime do you really care?

I looked into awhile ago.  It has something to do with the dye used in the CD.  I forget the exact times, but I think the cheap CDs break down in maybe 5-10 years.  Maybe it was 20-30?  I know the ones that aren't those amazingly great sales can last for 100-200 years.  That's good enough for me.

Maybe someone will come in with more expert opinions or maybe I'll find my old notes sometime.

You generally get what you pay for.  Those $0.10 CDs will break down faster.  There's a reason they are cheaper.


I vaguely remember something about this topic.  I think there may be an old thread on here about it.

[Bob]

I see I was referring to CD-R's.    I googled "cd life dye" and found what I was looking for...

https://www.cdmediaworld.com/hardware/cdrom/cd_dye.shtml
https://en.wikipedia.org/wiki/CD-R

The Wiki one is better I think.

I couldn't find my notes.  Oh well.



This one looks decent too.
https://www.amazon.com/exec/obidos/tg/guides/guide-display/-/17MPF9BC6G14P/102-7545004-5252915

[Bob]

I think Ted has some good ideas about backing things up.


Here are some more...

Backup to several types of media -- CD, hard disk, even tape, media by different manufacturers, etc.

Make at least three copies of each backup (on each type of media if possible).  Assume that something has a flaw.

If you really want it to last, go for quality.  They know what is better now.

Expect to have to transfer data in years to come.  (every 5 years?)

Store backups in multiple locations.  It's no good if they all are lost when disaster occurs.  There are places on the internet to back things up now.  Not to mention the amount of space email accounts are providing now.

Paper technology has been around for a long time.

There are probably services out there that will do your backing up for you.

Consider encrypting your files.

Consider how you will destroy the information.  What do you do with all the old backups?

[Tash]

yeah i'm paranoid my burned cd's are going to die one day, thus i keep it on my computer (and hope it doesn't crash or get stolen or then i'm really screwed!). i thought one had died, with monteverdi's l'orfeo on it that i'd only burned the year before, except i don't think it was a successful burn to begin with now that i think about it....but i except they'll die eventually, maybe in like 10 years time or something, hopefully when i can afford to buy an actual cd

[rc]

Wow Tash, you are poor! I will be very proud of you if, in ten years, you are able to buy an actual CD. It must be a milestone.

You know I'm kidding though. But I do win. I can't help it... So we all win, but some are cuter. It's not my fault!

[ted]

Bob:

Thanks for the ideas and the urls. Yes, I shall make fresh copies every few years and multiple locations certainly provide extra insurance. I shan't destroy anything though; other people can have whatever they want as I am not in the music business.

After making a few test mp3s I find their quality, even at high settings, too inferior to audio recordings to regard mp3s as permanent backups; wave files perhaps. I am sure professional services exist but a master of some sort still has to reside somewhere.

In a sense I do care about after I have died, not because I think recordings will set the world on fire, i.e. posthumous fame or anything silly like that, but because someone may get some enjoyment out of them. My teacher, a wonderful improviser, made hardly any recordings. It is a pity that nobody now, except the few alive who actually heard him play, can really benefit from hearing what was a very individual piano voice.

[gorbee natcase]

If you are me as little as a few days/ I have no respect what so ever