PDA

View Full Version : What's the life span of the average compact disc?



K.Mandla
March 19th, 2006, 10:27 PM
My dad showed be a news blurb he clipped from a magazine (I don't know what magazine) that suggested the average, nonprofessional compact disc will degrade after two to five years.

It went on to say that magnetic tape (?!!) was a proven format, with a lifespan of 30 years without error. But that the best and most reliable method was on a 7200rpm hard drive.

FUD alarms went off for me. I laugh at the suggestion of using magnetic tape, unless the medium is that much more reliable than it was circa 1970s, which is the only experience I have with that equipment. And why 7200rpm?

Can anyone set me straight? In the mean time, I'll see if I can track down the source of that article.

Zeroangel
March 19th, 2006, 10:29 PM
Yeah, depends on the media. Memorex CD-Rs disintegrate almost right out of the package.

K.Mandla
March 19th, 2006, 10:33 PM
:D I was wondering if I would spark some partisanship with that one.

I think the article was looking at any nonprofessional media, such as what you might get at your local Target store (or equivalent department-grade vendor, for those not trapped in the U.S. :) )

Bandit
March 19th, 2006, 11:18 PM
I read somewhere the life span of a un-abused CD left out in the light was 10 years.
Now I have many well kept generic CDs that are over 8 years old now that are perfectly OK and do not have any issues.
As long as the foil on top of the disc isnt scratched and the plastic on the bottum isnt badly scratched all should be good for a very very long time.
IMHO, it really depends on the wear and tear of the disc and how much it is used/abused... If you take very good care of them and keep them away from heat and light they should last forever or until they are obsulete and you throw them away :)
Cheers,
Bandit

Kvark
March 19th, 2006, 11:29 PM
They are made of plastic so they do decay sooner or later. The article is correct in saying that there is a risk for cheap CD-Rs to decay enough to cause data corruption in only 2-5 years. It happend with several disks for me and the disks had been used very rarely so it wasn't due to abuse. A couple cheap DVD-Rs have even decayed on me in less then a year. I think the higher data density of the DVDs means smaller decay changes are needed before it corrupts the data. In the other direction tapes have very low data density which should mean they tolerate far larger changes then CDs before the data gets corrupted. But the low data density is also the reason we don't use tapes anymore, just get high quality disks for important backups or re-burn to fresh disks every couple years.

JAwuku
March 19th, 2006, 11:51 PM
I find CD-RW's seem to degrade much more quickly than CD-R's.

Unbranded CD's seem to be of low quality, I only use them for trying out the latest live-CD's from Distrowatch! :D

Also, is it true that industrial-pressed CD-ROM's last longer than home-burned CD-R's?

benplaut
March 19th, 2006, 11:59 PM
7200rpm? wth?

i think flash actually lasts the longest.

imagine
March 20th, 2006, 12:02 AM
The article is correct in stating that CDs and DVDs (except DVD-RAM maybe) aren't a very reliable medium. The most important thing when designing such a disk is that it has to be as cheap as possible.
In a professional environment sometimes MODs [1] are chosen to backup important data. They look similar but work completly different.

[1] http://en.wikipedia.org/wiki/Magneto-optical_drive

rfruth
March 20th, 2006, 12:03 AM
Yes pressed CDs seem better than the CDs us end users create on our $ 49.95 burners ... as for how long media will last Murphy seems to have a lot to do with it http://www.murphys-laws.com/murphy/murphy-laws.html