[AV Media Matters] Really long-term preservation of audio recordings

[scott campbell <ScottCampbell@adidam.org>]

	I am not a trained audio technician, but have studied and read a bit
in the field for the last few years to help me manage my organization's
archival audio collection. In our archives, we have over 12,000 hours
(and growing by a 1000 every year) of original audio cassette
recordings. Some date back to 1971. We consider these recordings to be
priceless, as well as irreplaceble. I am charged with preserving them
for perpetuity--literally.
	In 1993, we began making DAT copies of our oldest tapes in the hopes
of creating an archival back-up, but halted that process in early 1994
based on the recommendations of the LOC--mainly the lack of standards
in DAT at the time.
	We then began making 1/4" analog R2R compilation tapes (again,
recommended by LOC). We stopped this process at one point for financial
and administrative reasons and have not resumed. In the meantime, I
have been doing a lot of thinking about how to best preserve our sound
archive for the really long term. Some of my main concerns:
	1. Durability of archival medium (tape is 50 years at best, CD is
really unknown/unproven though claimed for 100+ years, double ditto for
DVD);
	2. Method of "inscribing" the sound on the medium (magnetic is very
vulnerable, optical not so vulnerable, but both optical and magnetic
require availability of hardware, software, and powergrid
infrastructure to ensure ability to play back);
	3. Ability to replay under the most minimally available techological
conditions (perpetuity means being able to survive a great variety of
societal, climactic, and technological change).
	Trying to take all of that into account, I have been thinking of
transferring our recordings to some type of analog master metal record,
such as is created in the process of stamping LPs.
	Depending on the composition of the metal, such a disk would be far
more durable than tape. The inscription would be physical and not
subject to loss the way magnetic is, except if it was played many many
times--which is not something that would be permitted for an archival
recording. And the abilty to replay in the distant future would require
no more than a mechanical device, if more sophisticated technological
means are not possible or available.
	(Lest you all think I am just some Luddite survivalist, in the more
immediate term, we are planning this summer to begin transferring our
oldest recordings to CD as 96kHZ/24bit WAV files, for back-up and to
create accessibility without having to go to the aging original analog
cassettes.)
	My question is, is the idea of transferring to a metal master LP disk
feasible? Does anyone have any experience with this or know of anyone
who has?
	Thanks.

	Scott Campbell
	Director of Archives
	Eleutherian Pan-Communion