[SpaceMonkey]

A few of my commerical audio CDs are showing the early signs of some decay, and exhibiting errors in playback. So right now I'm looking at archiving them to high quality CD-Rs, likely the gold or silver kind with Phthalocyanine dye. Several sources have pointed me to MAM-A (http://www.mam-a.com/Default.htm) discs as having good recording quality and durability (hypothetically, as there just aren't any very good tests for longeivity). I was just wondering if anyone here had any experience with this brand, or had other suggestions I should look into. I would be doing the burning on my 466 MHz ("Digital Audio") G4 Tower with an add-on LG G33-4320B DVD/CD-RW combo drive.

Also, the actual decay of my CDs kind of mystifies me. I'm usually pretty paranoid about handling them, and these aren't the early ones from the '80s that tended to come apart prematurely. Is it possible that fingerprints on the label side can lead to corrosion? I know the label side is pretty thin, but I would figure that the actual label wouldn't let much in the way of finger oils through, much less the adhesive laquer layer below. I usually try to handle the CD as close to the center and edges as possible, but sometimes I'm lazy when putting them back in their cases, and there's some fingerprint build-up from that.

Ah well, no medium is perfect.

EDIT: Just remembered something else. MAM-A sells something they brand as "digital audio CD-Rs," which are based on their Silver CD-Rs, but "designed specifically for use in home audio systems." They don't go into much more detail than that. Does anyone here know more specifically how they're different?

[PacHead]

I haven't tried the brand you're mentioning, and I don't really use CD-R's anymore, but the term archival quality CD-Rs seems like a contradiction, since many of the old ones I have are starting to fall apart (various brands from cheap to expensive), and I'm sure I'm not the only one who has experienced failing CD-Rs. They're literally falling apart.

I wouldn't trust backing up anything to CD-R, if you're planning to store something for a long time, least of all for important archiving.

If the stuff is really important, I'd think of a different system perhaps.

my 2 cents

I've been burning a few DVD's lately, and I wonder how they're going to hold up in 10-15 years time.

[SpaceMonkey]

Originally posted by PacHead:
I haven't tried the brand you're mentioning, and I don't really use CD-R's anymore, but the term archival quality CD-Rs seems like a contradiction, since many of the old ones I have are starting to fall apart (various brands from cheap to expensive), and I'm sure I'm not the only one who has experienced failing CD-Rs. They're literally falling apart.

I wouldn't trust backing up anything to CD-R, if you're planning to store something for a long time, least of all for important archiving.

If the stuff is really important, I'd think of a different system perhaps.

my 2 cents

I've been burning a few DVD's lately, and I wonder how they're going to hold up in 10-15 years time.

Many brands use discs that come out of the same few factories, and so build quality even among name-brands tends to stay pretty low, not much better than the cheapest discs. From what I've read though, there are a few brands around that operate with their own factories and have higher quality tolerances. Different dyes and reflective layers, chemically at least, are more "stable" than others and should theoretically be less vulnerable to decay. Gold reflective layers in particular are supposed to be much less susceptible to corrosion.

I'm not looking for something that will last indefinitely, because nothing is indefinite. For me, at least, backing up a slightly damaged disc from time to time is just the most convenient way. I should clarify that the discs I'm talking about are two or three out of a collection of about 200, so it's not like it's a big crisis.

[Spheric Harlot]

I've had a Superdrive since March last year, and the first DVD-Rs are coming up with read errors now.

**** optical media for archiving.

If you're looking for an archiving method: Get yourself a swappable hard drive chassis, blow a hard drive full, remove it, and put it on the shelf. Multiple mirrors as per your requirements.

That is the best backup/archiving method I currently know of, bar none.

-s*

[SpaceMonkey]

Originally posted by Spheric Harlot:
I've had a Superdrive since March last year, and the first DVD-Rs are coming up with read errors now.

**** optical media for archiving.

If you're looking for an archiving method: Get yourself a swappable hard drive chassis, blow a hard drive full, remove it, and put it on the shelf. Multiple mirrors as per your requirements.

That is the best backup/archiving method I currently know of, bar none.

-s*

I'm not sure subjecting an unplugged hard drive to potential static or humidity is any more durable than some optical media. But anyway, my thread title was probably a little misleading. I'm not really wanting to archive large amounts of data. I just want to back up a CD once in a while onto another disc, and want to to it on discs that will be as reliable and durable as possible.

[Spheric Harlot]

Yep.

And "durable" and "optical" at present do not mix in any meaningful way, IME.

Hence the hard drive suggestion.

Of course, an external Firewire drive would be a viable solution, as well, if you're not talking about large amounts of data.

At least that ****er won't simply deteriorate by daylight.

[SpaceMonkey]

Originally posted by Spheric Harlot:
Yep.

And "durable" and "optical" at present do not mix in any meaningful way, IME.

Hence the hard drive suggestion.

Of course, an external Firewire drive would be a viable solution, as well, if you're not talking about large amounts of data.

At least that ****er won't simply deteriorate by daylight.

Out of curiousity, what brand of CD-R or DVD-R do you normally use?

[Spheric Harlot]

Originally posted by SpaceMonkey:
Out of curiousity, what brand of CD-R or DVD-R do you normally use?

I've started seeing problems with Apple-branded DVD-Rs, as well. Though my regular brand now is TDK.

But a half-hour of direct sunlight will kill any DVD-R disk, regardless of brand.

[tooki]

There are many factors at work:

1. Gold vs. silver reflective layer. Only MAM-A still makes real gold discs (all the other "gold" discs you see are silver with yellow paint). Silver readily oxidizes, reducing reflectivity.

2. Dye formulation. Some dyes are more stable than others.

3. Light exposure. All dyes will break down in light. Heat does the same thing.

4. Drive compatibility. Some drives read discs with a certain dye formulation better than others.

5. Storage quality. How's the disc been stored? This makes a huge difference.



So here's something to throw into the mix: all the big manufacturers sell special "medical" discs, which meet medical archival requirements. They cost more, but are designed for longevity.

I have been meaning to get some MAM-A gold discs for my archival stuff.

tooki

P.S. Verbatim makes medical archival DVD-R discs.

[srgprod]

First, for archival discs, assuming your recording music, I would buy Taiyo Uden discs. Taiyo Uden is the company, (owned by Sony) that first manufactured the CD. Their discs are first rate, best quality. They're hard to find but worth it.

Next, also for archival purposes, use a dedicated pro-quality standalone CD Burner hooked up to a quality CD player via coaxial digital in/out. Marantz, Sony, Tascam, HHB, Denon make the best ones. I wouldn't trust using a computer drive at multi-write speeds to give you stable error-corrected copies. Some of theses burners only read CD-Music discs but a computer drive will read all formats.

Hope this is helpful.

[tooki]

Taiyo Yuden (it has a Y) doesn't make gold blank media any more.

Without gold, the reflective layer will eventually oxidize and lose reflectivity.

No doubt Taiyo Yuden's discs are of high quality, but for archival purposes I would choose only a real-gold disc.

tooki

[srgprod]

For archiving any data music or otherwise. The best solution is to archive to flash drives. They are more expensive but will maintain you music files indefinitely (i.e. 100+ years). No moving parts , indestructable w/ absolute data integrity. There's a company, M-Systems, out of Israel that makes the best of these drives.

Theye can be hooked up to a standalone pro CD burner or CPU.

[tooki]

Flash drives most decidedly do not provide "absolute" data integrity.

For one thing, they're sensitive to static discharge, and they can also lose data due to physical impact. They are also sensitive to moisture.

Besides, flash is not practical for most purposes because of its extremely high cost. At about 10¢ per megabyte, flash is vastly more expensive than optical or magnetic media.


Besides, right now, the most stable known data archiving medium is magneto-optical. Because it requires the combination of both light and magnetics to make changes to the media, it's impervious to either one alone. It's immune to magnetic fields. Immune to light. Immune to heat. Waterproof. In a shell so it doesn't get scratched. The biggest downside is that MO drives aren't terribly fast.

For most people, regular backups onto properly-stored optical media, combined with backups to hard disk, provide a solid, reliable and practical way to back up data.

tooki

[srgprod]

Tell this to NASA, US, German, Russian and Israeli military. That's what they use for data storage, ie Space launchs, Aircraft and Tank data storage. Flash drives are almost indestructible. Yes, they are costly gb/$$ basis, but for achival purposes, its the most effective storage there is.


"Flash drives most decidedly do not provide "absolute" data integrity.
For one thing, they're sensitive to static discharge, and they can also lose data due to physical impact. They are also sensitive to moisture." Not true!

[tooki]

You get it wet and it may fail. That's the nature of electronics, if they haven't been specifically designed to be waterproof.

Flash memory is sensitive to static discharge, like any other memory chip. People have lost data to this.

There have been stories of flash media failing from physical impact. Yes, they can handle a lot more than a hard disk can, but they are not indestructible.

Flash memory also has a finite number of write cycles, after which it begins to become unreliable.

Do you think the military is going out and buying flash drives like a consumer would get? Of course not! And even so, the military's not using them for archival purposes. They're using them as on-line storage, as replacements for hard disks, which are of course sensitive to all sorts of things.

Don't get me wrong, I love flash media, and I do think it's one of the most reliable media out there. But using it for archival purposes is absurd.

By the way, when I was disputing your assertion that flash memory gives absolute data integrity, I should have added that NO media provides absolute integrity. All the media we have invented can be damaged or destroyed in some way or another. There is no absolute.

tooki

[srgprod]

My last word on this...

The data storage used by NASA on every retrievable and non-retrievable mission utilize flash drives. These drives sink to the bottom of the ocean, are drilled into the earth for 50-100 feet upon immense impact, they withstand tremendous radiation and massive doses static electrical orbital and sub-orbital charges, freezing (-1500C) and + 500C degree temperature variations and no data loss. I don't know what you're referring to but these are the facts.

I've designed and built these systems for more than 20 years, I'm just giving you my experience.

A CD will turn into a unreadable coaster if dropped and scratched. I've even had them crack when being taken out of a jewel case.