Music CD mystery

[catgate]

I took out a CD yesterday that I had not played for a couple of years or so. Sadly, when I put it into a player, of any sort, it would not play.

I have several CD and DVD drives on computers, and a couple of other CD playing devices, and none of them can coax any music out of it.

It is not a home made copy of downloaded stuff, it is a CD given to me by a member of the band on the CD and it has played perfectly several times before.

As far as my computer drives are concerned they see it as a "Blank CD". Since it was last played it has lived in a CD rack on a shelf above one of the computers, along with other CDs.

I am rather puzzled about it and any useful suggestions would be more than appreciated.

It is of French origin.

[rong]

"It is of French origin." that's the problem then, they are messing you around again. trust the French to cause trouble

[-pops-]

There was a CD "disease" a few years ago called CD rot in which the lamination of the polymer layers failed slightly (possibly due to the stress conditions encountered during the stamping of the central hole). This allowed the ingress of damp air between the laminates and the metal film tended to oxidise. This "rot" was progressive as more oxidation caused increasing delamination such that the disk became unusable.

That was commercial stamped disks. A similar thing can happen with writable disks but there is the added problem with those in that the photosensitive dyes degrade with time such that some of the early CDR and CDRW disks had a very limited lifespan - especially cheaper brands.

I have a collection of (cheap) DVDRs about three years old and only about 10% are playable. I now use better quality disks.

[AlanHo]

Some CD's produced for minor bands which have only small sales volumes are not pressed - but are commercial CD-R's.

These can fail at any time after about 3 years - actual life being dependent on the quality of the CD, how well it was burned, it's storage condition, how often it has been played and the biggest factor of all - Sod's law.

Being French it could be the result of all the above factors.

[catgate]

Well, well, well.

Thank you chaps.

That seems to back up my theory about the modern methods of storage of important information.

If it had all been inscribed on stone with a chisel it would have lasted longer than 3 years....well.. it may be over 5 years since the CD was created.

[AlanHo]

Well, well, well.

Thank you chaps.

That seems to back up my theory about the modern methods of storage of important information.

If it had all been inscribed on stone with a chisel it would have lasted longer than 3 years....well.. it may be over 5 years since the CD was created.

It would need to be a round stone to fit on the player - hence the idea of the Rolling Stones was born..........................

[catgate]

Well, well, well.

Thank you chaps.

That seems to back up my theory about the modern methods of storage of important information.

If it had all been inscribed on stone with a chisel it would have lasted longer than 3 years....well.. it may be over 5 years since the CD was created.

It would need to be a round stone to fit on the player - hence the idea of the Rolling Stones was born..........................

I was never very carried away by rock and roll.

[-pops-]

Since my earlier comments in this thread, I have examined a number of old optical disks and found the corrosion phenomenon is quite widespread - CDs and DVDs, home-burned and commercial. There is visible deterioration on the majority of older (cheaper) disks. This shows itself as a loss of the bright metallised finish which is replaced by a dull grey/white powdery appearance which seems, in some cases, to radiate into the "working" area of the disk.

Remember that, unlike a gramophone record, a CD or DVD reads from the centre outwards so that damage or deterioration, possibly not easily visible, in this area - where the digital data for indexes etc. lie - will manifest itself immediately as a non-working disk.

[catgate]

Since my earlier comments in this thread, I have examined a number of old optical disks and found the corrosion phenomenon is quite widespread - CDs and DVDs, home-burned and commercial. There is visible deterioration on the majority of older (cheaper) disks. This shows itself as a loss of the bright metallised finish which is replaced by a dull grey/white powdery appearance which seems, in some cases, to radiate into the "working" area of the disk.

Remember that, unlike a gramophone record, a CD or DVD reads from the centre outwards so that damage or deterioration, possibly not easily visible, in this area - where the digital data for indexes etc. lie - will manifest itself immediately as a non-working disk.

That is interesting, pops.

I have had a look again at the "working side" of the disc in question and I can see nothing that looks anything other than "bright metallic". It has a wonderful prismatic effect, showing a most odd rainbow. One of the colour separations is most peculiar. It is the interface x in V I x G Y O R. There is no blue, and the transition is a sharp line.

I then looked at others and found most of them to be the same. Odd I thought, where has the blue gone?

So I switched on a tungstone lamp (we are on fluorescents apart from a couple of table lamps) and lo and behold the blue came back in the other "refraction" that was formed.

So, I have lost some delightful "Trad" and gained some more Knowledge.

I'm not sure if it was a fair swap.