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From: "[log in to unmask]" <[log in to unmask]>
> One last comment from the peanut gallery dealing with a preservation issue
> concerning analog tape. We do a lot of disaster recovery work at our lab
> and ferric oxide analog audio tape stands up to disaster exposure very
> If we receive the tape within a few days of exposure, better than 95% of
> ferric oxide analog tapes can be restored to playable condition. Of the
> balance, more than 95% can be partially restored so the content, if not
> full quality can be recovered. This means less than 1/4 of 1% is lost.
> don't expect to get those sorts of results with digital recordings that
> been submerged. Of course, the best preservation strategy is redundancy
> geographically separated sites- but- if you only have one copy and
> happens, I'd place my bet on recovering the recording from analog tape
> before digital tapes or hard drives.
The interesting thing is that shellac-based phonorecords appear to have a
survival rate than most post-WWII media! I recently acquired a bunch of old
which had been considered detritus for at least a decade or two, and thus
stored or handled under ideal conditions. They date back to at least 1910 in
some cases. Yet, in spite of the mishandling, most of the damage (insofar as
there is any) appears to be "original" (i.e. played too often, or with worn
needles on early hardware) rather than gradual age-based deterioration.
If shellac discs have a "best before" date, I don't think anybody has any
rational idea what that might be! Mine go back to 1896...