[Scott Dorsey]

geoff wrote:

I have boxes of CD-Rs that no longer play reliably.

Azo ? Aluminium ? Or the better Cyanine or Phthalocyanine and gold
metalisation ?

For a long time I was buying the cheapest ones possible from Cassette House,
because they could be had for $16 each when the Mitsuis were $25. Once the
price of the Mitsuis dropped down to a couple bucks each I started using
those exclusively.

I have recently been using a lot of the Verbatim azo discs for high speed
duplication, but a lot of what I do is still using the 1X realtime CD recorders
which don't like those discs. So I am still using the last of my stock of
Mitsuis.

If your archive choice is optical best go with the latter, or better
still M-Disc.

M-Disc is cool and the idea is a good one, but it won't play in a CD player.

The thing with digital is you have many choices of media and
technologies. Even chisel-and-cave-walls if you want to go back to basics.

And if you decently digitally record your precious tape master, it can
be perfectly preserved with all it's, um, 'favourable aspects'. Duping
onto another tape will accumulate another generation of its flaws.

Yes, the good news about digital is that you get lossless duplication. The
bad news is that the effects of degradation are abrupt rather than gradual,
and that some of the existing media are known to have poor longevity.

Of course running a safety (with equal care and attention as the actual
master) when producing the original master tape will save that
generation loss.

But then you have a safety which is just as old as the original and likely
subject to similar degradation. Better than nothing, though.
--scott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."