Adding more indepth data to David's technical contribution, audio and video tape (aka magnetic media) most assuredly do suffer chemical deterioration with time, regardless of usage (or non).  Both the binder resins and backings used in manufacturing not only affect the audio quality, noise level, head contact and friction, they are also contributing factors to the aging properties.  While they've improved over the years - different base acetates,  the incorporation  of the polymers (mylar) backings,  chromium dioxide binders (known to most of you as tapes with the Cr02 label), better oxides (less shedding ) etc - it remains an undisputed fact that tape itself is a flawed archival medium.  Even with the longer shelf lives today, you still have the inherent generation loss with each copy you make - and you still must make a duplicate of the original before it bites the dust.

Digital media does not suffer the same fate.  Cloning anomolies, while still under intense debate to date, is minimal when compared to those of tape to tape.  As far as playback availability.  Not as large an issue as you think.  Evolving architectures (i.e. the software used for creating, storing and displaying a digitized  file) are generally supported in new products, either by compatibility or by file conversion software built in.  It would be death to any business to ignore current and older formats.  You still see turntables around for your stereo, yes?

At worst case scenerio, you make a common player copy on a CD-ROM, DVD, or magneto optical disk (MO's) and record a new digitized version in your new system software.  It is highly unlikely these formats will disappear and ignore compatibility in the foreseeable future.

Terri



David Haberstich wrote:

>
>I think several different preservation problems are being conflated here.
>The problems of the film industry were due to deteriorating nitrate film
>base, deteriorating acetate film base, and fading color dyes, in addition to
>such physical damage as wear and tear through usage, broken splices, etc.
>Magnetic media such as audiotape and videotape deteriorate through normal
>usage and poor storage conditions even when the tape remains in good
>condition, and both analog and digital records can suffer the same fate.  In
>addition, digital media are only as permanent as the availability of
>equipment for access and playback.

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