Heads Up on CDR Degradation - New Results

[dubbmann]

Hi all,

Those of us who are old enough will recall the conjecture that "CD creep" will cause the eventual degradation and unreadability of CDRs recording digital data. This obviously proved untrue or at least premature.

Here's a new article saying that the demise of CDRs recording 15-25 years ago may be at hand.

https://www.howtogeek.com/682807/the-cd ... eed-to-do/

I don't vouch for the article but thought I'd share it for SoSers to take under advisement. FWIW, I have noticed some of my CDRs are beginning to show problems where before they were completely playable

Cheers,
d

[muzines]

I pulled out most of my optical media a few years back and backed the contents up to HD, and even then, I was starting to get problems reading disks, so I'm wary of anything on optical media if it's been around a while.

If it's your only copy of data, I'd be very sure to get take copies of the data onto another format rather than trust that you can pull out the optical media 10 years from now and expect to be able to read it...

[James Perrett]

I'm regularly picking out old CD-R's from 20 or more years ago and not seeing any problems apart from the one bad batch that went bad very shortly after being recorded. My discs are kept in the dark in a normal room at a fairly even temperature. There have been plenty of these articles but they just don't tie in with my personal experience.

Yes, it is always safest to have more than one backup but I'm not going to be throwing out my CD-R's just yet.

[cyrano.mac]

It depends on the quality of the media used.

The one plant that made quality media, ended with the Fukushima disaster.

Like James, my CDr archive goes back nearly 25 years and doesn't show any problem. The one set that went bad 'till now, was made on an early version of OSX. I must've been wary, cause I also burnt a set under OS9 and that one's still fine.

Mind you, I no longer use CDr or DVDr for archival. HD's are cheaper.

[Martin Walker]

I was given a box of Verbatim CD-R disks that seemed to burn perfectly, but gave up the ghost with excessive gapping within a week

I still burn at 8x for audio CDs using Wavelab 8, which works perfectly with most media. Not sure why these object to my burns.

Martin

[Eddy Deegan]

Burnable media does seem to be a bit of a minefield. I was transferring the contents of 30 or so (Hi-Space and Verbatim) backup CDs and DVDs (burned between 10 and 15 years ago) to an external SSE drive earlier this week and found that about a third of them had some unreadable files, although others on the same disc were OK.

[Hugh Robjohns]

The die layer is an organic compound (several different types were used) and it naturally decays over time. Some claimed a reliable life of over 100 years, others less, but storage conditions make a big difference -- especially light exposure, temperature and humidity.

Some of the CD-Rs I made in the early 90s are still fine... and some aren't! (But they were all transferred to NAS boxes with a good backup strategy decades ago, along with my DAT tapes...)

H

[muzines]

The bottom line is, regardless of what media you used, or how well you stored them, there's no way to know* they've gone bad until you try to read them.
Not the most reliable of storage for important data, which I why I don't trust it at all any more...

* In the worst cases, there's often visible degradation happening, but stuff can become unreadable *way* before that happens

[ken long]

I think the bigger issue here isn't the CD-Rs which, as others have pointed out, can last quite long if stored in the right conditions. The issue is the diminishing availability of drives and really we're talking about drives that can report errors accurately.

[ef37a]

Put it on Music cassette!
I have recently played some I made over 40 years ago and they are still fine.

Dave.

[Hugh Robjohns]

It's even worse if CD-Rs are recorded as (red book) audio CDs rather than as (orange book) CD-ROMs because the former format has a MUCH weaker error-protection/correction system which intentionally relies on concealment by interpolation when error rates rise too high, whereas the CD-ROM format has a far more sophisticated error-protection/correction system and can cope with a lot worse and still deliver bit perfect results...

But every system has its limits and recordable CD-ROMs fail too, of course... Magneto-Optical formats are more reliable... but still not 'for ever'

[Hugh Robjohns]

Put it on Music cassette!

They tried that with the DCC format... never did live up to the hype...

[ef37a]

Put it on Music cassette!

They tried that with the DCC format... never did live up to the hype...

Got one! It worked brilliantly several years ago but now borks and says "clean heads".

Actually I really like Mini Disk and I understand there is now some software that can do fast transfer with certain machines? Got two of those, a Sony and a Grundig by crickey!

Although I was never bothered by the compression used for MD I would gladly trade the 90 minutes run time for say 60mins (or less, got a SHED load of discs!) of linear .wav.

Dave.

[ken long]

Put it on Music cassette!

Actually I really like Mini Disk and I understand there is now some software that can do fast transfer with certain machines?

The last (or one of the last) Sony devices the MZ-1 will do this. The software is called Sonic Stage (you'll need to run a virtual XP).

https://www.sony.com/electronics/suppor ... s/00024289

[ef37a]

Put it on Music cassette!

Actually I really like Mini Disk and I understand there is now some software that can do fast transfer with certain machines?

The last (or one of the last) Sony devices the MZ-1 will do this. The software is called Sonic Stage (you'll need to run a virtual XP).

https://www.sony.com/electronics/suppor ... s/00024289

Oh well that's buggered that then Ken! I am not nearly THAT computer smart!

Dave.

[Hugh Robjohns]

Actually I really like Mini Disk...

It was an elegant design, intended to serve as a more compact and practical 'walkman' format than the 'CD Discman'.

And they learned from the mistakes of the CD, in so far as the main cause its replay problems was surface damage and contamination, so encasing the disc in a sealed cassette made it far more reliable and immune to 'rough' handling. And the user-recordable discs used a magneto-optical principle that makes them far more robust than CD-Rs.

Although I was never bothered by the compression used for MD I would gladly trade the 90 minutes run time for say 60mins (or less, got a SHED load of discs!) of linear .wav.

It would have been a lot less. Sony's ATRAC was a 5:1 data-reduction system.

Amusingly, After Sony had launched the MD with ATRAC, some legal representatives of Dolby Labs went knocking on Mr Sony's door with copies of Dolby AC3 (Dolby Digital) worldwide patents pointing out where Sony had accidentally and unknowingly infringed upon them... A settlement was eventually reached and I believe Sony pays royalties to Dolby on its ATRAC-based systems.

[CS70]

The bottom line is, regardless of what media you used, or how well you stored them, there's no way to know* they've gone bad until you try to read them.

Schrodinger would have had a laugh

[Martin Walker]

...as would his cat (if it was alive)

[Hugh Robjohns]

...as would his cat (if it was alive)

Hang on a minute, I'll go and have a look to see....

Oh... Wait...

[ef37a]

Waaay ago son was building tracks, part on PC and part Tascam A 3440 and would burn stuff to disc....after disc....after disc playing them on my hi fi system. Got a bit expensive so dad had the bright idea of buying 10 CDRW so he could check it on the hi fi, scrub and do again.

Unless you handled the discs with cotton gloves and in dust free conditions we were lucky to get 4 cycles from each disc and after a month they were all buggered. Cheaper to buy 100 CDR and stand the coasters!

Dave.

[Tim Gillett]

Put it on Music cassette!
I have recently played some I made over 40 years ago and they are still fine.

Dave.

I believe that for critical data, digital magnetic tape backup is still very much used in government and industry. Its just that most of us don't see it, and nowadays tape as a storage medium is often regarded as not sexy enough.

[CS70]

Dave.

I believe that for critical data, digital magnetic tape backup is still very much used in government and industry. Its just that most of us don't see it, and nowadays tape as a storage medium is often regarded as not sexy enough.

Well it depends on what government (and branch) and industry of course but western governments at least for new data, nowadays usually store permanent data in replicated clusters of hard disks in physically separate locations. The key to longevity is automatic periodic replication, existing concurrently in separate media.

There are sure vaults of old tapes somewhere - given the procurement cycles typical of governments, many different technologies coexist for a very long time.

[muzines]

There are sure vaults of old tapes somewhere - given the procurement cycles typical of governments, many different technologies coexist for a very long time.

Indeed. Vaults of tapes like, oh those record companies, that kept single unbackedup master tapes of all their artists' recordings in a single warehouse... that went up in flames...

[Tim Gillett]

Dave.

I believe that for critical data, digital magnetic tape backup is still very much used in government and industry. Its just that most of us don't see it, and nowadays tape as a storage medium is often regarded as not sexy enough.

Well it depends on what government (and branch) and industry of course but western governments at least for new data, nowadays usually store permanent data in replicated clusters of hard disks in physically separate locations. The key to longevity is automatic periodic replication, existing concurrently in separate media.

There are sure vaults of old tapes somewhere - given the procurement cycles typical of governments, many different technologies coexist for a very long time.

Tape continues to hold advantages in terms of cost per terabyte, much longer than hard drive reliability, air gap protection, and especially for massive amounts of data where access is infrequent.

[Tim Gillett]

There are sure vaults of old tapes somewhere - given the procurement cycles typical of governments, many different technologies coexist for a very long time.

Indeed. Vaults of tapes like, oh those record companies, that kept single unbackedup master tapes of all their artists' recordings in a single warehouse... that went up in flames...

Well yes but in the same fire would HDDs have fared any better? And these days tape's lower cost per terabyte also makes duplicate copies in different locations more viable. In addition the cost of now storing say the contents of one 10.5" 2" reel of multi track audio on modern digital data tape compared to the original analog format is miniscule. We're talking around 200 terabytes per tape unit.