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The awful truth about CDs, do they have the same shelve life as LP's ?

The answer is properly not. Recent studies have shown that the chemicals used in their manufacture of CDs have reduced their life expectancy to ten years, not all but many, as per Paul Mcgowans email. The suggestion was given that if you have suspect CD's they should be re-copied. But my question is how do you identify these? I can tell you that I have a great deal of LPs and I can play anyone of these with great success and some are 40 years old. This no doubt would give some audiophiles another good reason to hold onto their belief that LPs are the way to go.
phd
larryi
3,728 posts
 

I have ripped more than 4500 CDs to my NAS.  The ripper provides data, such as errors encountered in the ripping process.  Not one of the CDs had an error.  Some of the CDs date from back at the beginning of CD production. 

I believe that the concern raised about CDs came from the experience with laser discs, something that predates the CD.  Laser disc were subject to deterioration when air managed to get between layers of its sandwich construction causing the metalized reflective layer to oxidize.  I have seen this "laser rot" on laser discs.  But, CDs are made differently and are not as prone to problems with oxidation. 

As to the extremely long run, who knows?  Will the polycarbonate plastic in CDs begin to cloud or become fragile?  I don't have to worry because my CDs are ripped and then put on shelves as backup or for their cover art, booklet information, etc. 

bondmanp
1,789 posts
 

I think this was already touched on, but the durability issue applies mainly to CD-Rs.  These use a heat-reactive ink layer which allows a laser to burn the digital signal onto the disc.  This ink can fail over time.  I have a few CD-Rs I burned in 2001 that skipped enough to warrent a re-burning of them in the last year or two.


However, commercial CDs have the digital signal stamped into an aluminum layer that is sealed in plastic.  Unless that plastic seal is compromised, it should last many decades, if not indefinitely.  Deep scratches and high heat can warp or compromise the plastic layers, or prevent the laser from reading them properly, and are the most common reason commerically stamped CDs fail.  So, as common sense would dictate, proper care and storage of your CDs is a must.


If you have a server with all of your CDs on it, and backups for that server, you should be fine for the rest of your life.  When I have a CD-R go bad, I burn a fresh CD-R from my hard drive. (I use CDs in the car, and I get to every CD once in about three years, so I can flag any failing CD-Rs for replacment.)  Currently, I am paying about 22 cents apiece for Taiyo-Yuden CD-Rs.

ihor
88 posts
 
This was an issue back in the late 1980s/early1990s and dealt primarily with discs manufactured for Hyperion.  This was attributed to discs manufactured by a specific CD pressing company, and dealt with a lacquer coating that eventually allowed air to reach the aluminum 'data' layer and cause oxidation.  Most of the labels that used this particular manufacturer were classical in nature (e.g., Deutche Gramaphone, Archiv).

http://www.classical.net/music/guide/society/krs/excerpt3.php

Of my 2,000 cds, I have had only 2 discs become unplayable: both were HYperion label and both showed discoloration suggesting oxidation of the aluminum layer.  None of my other discs, including ones dating back to the mid-1980s, all still play with no problem.


gsm18439
895 posts
 
I have thousands of CDs (unfortunately, no joke) going back to the 1980s (I bought the first Meridian modded Phillips top loading CDP) and have had only a handful go "bad" - if that.
grateful's avatar
grateful
104 posts
 
I too read the PS Audio email talking about CD longevity issues...  Having a vested interest (like most of us) this is my experience and research.

30+ years ago, while in college I used the new miracle of word processing technology to write my papers, Word Perfect was the greatest then.  First saving my files to the standard 3 1/2" floppies (5" had just gone out of favor about 10 years earlier), then moving to ZIP drive, then to MO drive, then to CD rewrites, then to HD, then to servers - why so many???  Because as the years and decades clicked off, I found that each medium would fail, every last one, not a single one was 100% safe as archival.  The US Library of Congress has found the exact same thing.  Now having said that, there are several factors that contribute to archival failure - manufacturing, materials, radiation, heat, moisture, storage, handling, and so on...  Again, my research has only verified what the Library of Congress has researched, many universities has researched, and my own eyes of personal experience through the decades...  

So to cut to the chase - CD's and vinyl are definitely the best, hands down by a long shot, archival medium existing today as long as (here is the key) the initial manufacturing and materials were sound and they are handled and stored safely and protected from heat, UV, and moisture.  Both mediums, as such, should last for 100+ years.  Again the key is proper handling, storage, and protection...  Both mediums are fragile, vinyl a bit more than CD.

The argument in Paul's article was to copy/burn all your music to digital (not to mention Paul's great new products related to digital...hint hint).  Again, to cut to the chase; if you want luxurious convenience to scroll through and enjoy your music collection from the comfort of your armchair then by all means move your collections to digital BUT, be warned!!!!  Digital storage is significantly worst than old fashion parchment for archival storage!!!!  Google and the other data enterprises replace all their hard drives every 3 to 5 years for a reason and they use enterprise/industrial quality units too not cheapo retail drives.  Hard drives fail fast (in comparison) and the new solid state drives are no better and some worse than the spinning platter.  Data centers/cloud computing keeps data because that data is constantly recopied somewhere else...  but does this continuous recopying of files possibly introduce errors, of course.  I have several photo files that have been recopied numerous times and I have noticed pixel errors and even complete file corruptions.  

Again, I read Paul's article and again I had hopes of the future well up inside me but again after revisiting my sources I still do not see digital even close to gaining my trust of protecting my music or anything else for that matter.  
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