How common is CD "rot?"

Rob Babcock · « **on:** 13 May 2003, 09:18 pm »

Has anyone gone thru their CD collection to see how many discs are exibiting "pinholing" or rot? (I guess rot and the formation of holes in the reflective layer aren't exactly the same phenomenon).

I just noticed last nite that my Chris Issak "Heart Shaped World" CD is developing small pinhole sized holes in the reflective layer. Of course, this would have to be one of my favorite discs, too. I was gonna buy a new one today but I forgot while I was at BB for NRT. The disc still plays fine, but in my experience, the holes will continue to grow over time, and the process seems to accelerate as time goes by. I think I bought the disc shortly after it's release, so about '86-87 if I recall.

Now, I've only noticed this on one or two of my own discs, although about a half dozen of my brothers discs have this problem. It's unknown to me whether this is an issue that arises from a specific manufacturing defect or how many discs are affected.

How many discs have you guys noticed this on?

Sa-dono · « **Reply #1 on:** 13 May 2003, 09:50 pm »

None that I've noticed so far. I'm going to go through my collection soon to weed out the cr*ppy recordings soon..so I guess I'll find out soon enough.

I have noticed a lot of DVDs these days having little air bubbles from the dual layer.

dogberry · « **Reply #2 on:** 13 May 2003, 10:35 pm »

Oxidation of the aluminum? I dunno. I did a search for "cd rot" on Google and found dozens of hits. I've never seen it myself.

Thump553 · « **Reply #3 on:** 15 May 2003, 08:38 pm »

Between the CDs I've burnt (I'm an avid concert trader) and the ones I've bought, I have well over 1,000 audio cds. My collection dates back to sometime in the mid-80s. I've never experienced any CD rot at all. How big do these pinholes become? Are you sure no one else in your household mishandled the CDs? The coating is very thin and the aluminium film is pretty fragile. Some poor quality CDRs (but I presume not commercial CDs) appear to be not coated at all.

I once had to totally destroy some CDRs. It took vigorous brushing with a steel wire brush to penetrate the coating and film, but once its penetrated it comes off very easily.

Rob Babcock · « **Reply #4 on:** 16 May 2003, 01:58 am »

I can say with about 95% certainty that the pinholing isn't a result of mishandling, although damage to the top will kill a disc faster than damage to the bottom. Curiously, though, I have an AC/DC cd I bought from a buddy in '86. He'd written his name on top w/a Sharpie, so I used nail polish remover to take off the writing. Worked like a charm on a dozen other discs I tried it on, but this time I wasn't quick enough and took the plastic off the top!

But amazingly, even after 16 years of bare aluminum the thing still plays perfectly.

As to the size of the pinholes, my brother has a Frehleys Comet CD with BB sized holes in the reflective layer. My CI disc literally has only small pinholes.

Again, I've seen this very rarely, but I think I can safely attribute it to a defect rather than bad handling.

I hope others will post with their experiences. With the boys all going gaga over their precious 'vinyl' right now, I don't think anyone stops in here anymore!

CELT · « **Reply #5 on:** 21 May 2003, 01:51 pm »

My disc library dates back to 1983. This thread got me looking at my oldest discs. Other than some light oxidation of the outer edge of two; I didn't see anything out of the ordinary. Let me say that I always have stored my CD's in their jewel boxes or whatever they were originally packaged in. All are stored on shelves, upright and away from heat and direct sunlight (the two worst enemies of the CD). Now as far as pinholes, this is something I always look for whenever opening up a newly purchased disc. I started this practice back in '87 when Crapitol started manufacturing poorly made Beatles discs. They were prone to have pinholes and other anomalies. In my experience the American EMI and WEA have the worst pressings. Many are manufactured with pinholes, rough edges, lightly warped or eccentric. It amazes me the laser servo mechanism can keep up with the mess that is going on with these discs, not to mention the error correction that is going on. The imported Japanese discs are much better in this regard.

Rob Babcock · « **Reply #6 on:** 21 May 2003, 07:06 pm »

I wish I had a wayback machine to monitor my CDs from the day I bought em! Like I said, it's a possibility that the discs were mishandled by someone other than me, but I don't think so. And the pinhole seems well contained by the plastic; ie there's no hole in the top or bottom of discs.

Luckily the number of pinholed discs I have is very low, and thankfully none of them are out of print.

MaxCast · « **Reply #7 on:** 21 May 2003, 07:29 pm »

I have many rotten CD's if that helps.....wana buy em?

CELT · « **Reply #8 on:** 21 May 2003, 08:50 pm »

Rob: The "pinholes" are the deterioration of the aluminum reflective surface inside the disc. CD's are stamped like vinyl records, a reflective surface is added and then a protective coating is applied to the label side. There will not be any holes develop that go all the way through. However, no has mentioned that this phenomenon is the very reason that DCC, MCA, Sony and MoFi all offered "gold" discs at one time or another. The gold layer does not tarnish nor will it deteriorate.

Rob Babcock · « **Reply #9 on:** 22 May 2003, 02:07 am »

That's true; my I only meant that if the pinholing was caused by mishandling instead of oxidation or defect then there'd probably be damage to the top or bottom of the disc.

It's also true I've never experienced this with gold discs, but then I have very few of those.

nathanm · « **Reply #10 on:** 29 May 2003, 06:01 am »

Interesting phenomenon. That may have been what I saw on a disc I recently threw away. I thought it got stepped on and grit\dirt from the floor gouged the disc, but now that I think of it, the tiny holes were on both sides. Oh well, the CD sucked anyway. (Meliah Rage) Not much you could do about this problem though, unfortunately.

Tom Bombadil · « **Reply #11 on:** 11 Jun 2003, 04:12 am »

I've had a couple of instances of laserdisc rot, where there was visible deterioration. However out of my 600-700 CD collection, I've never noticed anything nor heard any popping or dropouts. That's not to say that there could be some minor pitting in there somewhere.

As far as the gold discs go, that was much more of a marketing ploy than anything else. They sounded better (usually) and didn't deteriorate because they were mastered and manufactured better. A properly made aluminum CD should last for decades, and there is no reason why it can't sound every bit as good as a gold CD, which is obvious as most of the finest sounding CDs are on aluminum discs - note all of JVC XRCD, Reference Recordings, Mapleshade, all of the SACDs, DVD-As, etc..

Rob Babcock · « **Reply #12 on:** 11 Jun 2003, 05:13 am »

Most of the pinholed discs I've seen play fine, but a couple have audible dropouts.

The gold discs were mostly marketing, but gold is the only metal that cannot oxidize. Sure looks cool too!