Best Practices For Audio Preservation
5.1 Preservation Overview
Long-term Preservation Storage
ong-term storage has been probably the thorniest issue in audio preservation for the past
ﬁfty years if not more. Particularly in the U.S., we have argued for decades about what,
if any, digital format is preservation-worthy or sufﬁciently robust to be worth the cost of
reformatting. Historically, sound archivists have focused on the importance of the carrier—
how long will it last? Can we predict when it will fail? A major paradigm shift was born around
1990 when international archivists began questioning the search for an eternal carrier.
change in strategy, now widely accepted, focuses on preserving the content, not the carrier.
Once content is digitized, this new strategy relies upon regular migration from one carrier
to another in the digital domain. It therefore must take into account the need for a feasible
migration path in the near- to medium-term—otherwise, resources are ill-used and retrieval
costs are high. Based on a growing corpus of research, IASA-TC 04 recommends the use
of digital mass storage systems for the carriers of preserved content, preferably managed
storage—that is, digital storage where the characteristics and condition of ﬁles are carefully
monitored—and experience internationally supports this approach. While “no target format
is a permanent solution,”
digital mass storage offers the option of automated routines
including migrating outdated formats forward in an automated fashion along with regular
data-integrity checks of the contents. This greatly reduces both the opportunities for error and
the resources required in the performance of these tasks.
Digital mass storage systems form essential components of preservation and access programs
at the National Library of Australia, at many European national radio archives, and at archives
such as the Swiss Memoriav.
In the U.S. and Canada, major universities such as Harvard,
Indiana, and the University of California; the Library of Congress with its new National Audio-
Visual Conservation Center in Culpeper, Virginia and others are building and maintaining
such systems as the consensus grows that this storage approach will work for the future. An
important ongoing initiative spearheaded by OCLC’s RLG Programs, the National Archives
and Records Administration, and the Center for Research Libraries has worked to deﬁne
the characteristics of a reliable digital repository and develop the means to certify such a
The terms “preservation repository” and “trusted digital repository” refer to these
types of storage solutions that provide preservation services beyond bit-level storage.
Both IASA-TC 03 and TC 04 outline core principles of digital storage.
were produced for the audio preservation community but the same principles are found in
various digital library publications. The recommendations in our report are based on these
works and on our experience implementing preservation repositories and using digital mass
83 Dietrich Schüller, “Preserving the Facts for the Future: Principles and Practices for the Transfer of Analog Audio
Documents in the Digital Domain,” AES Journal 49, no. 7/8 (July/August 2001), 618.
84 IASA, Technical Committee, IASA-TC 04, 3.
85 The experiences and decisions of a number of institutions who have been using digital mass storage since 1992
appear in: IASA, Technical Committee, IASA-TC 04, 49-51.
86 Center for Research Libraries and Online Computer Library Center, “Trustworthy Repositories Audit &
Certiﬁcation (TRAC): Criteria and Checklist” (3 September 2007),
87 IASA, Technical Committee, IASA-TC 03, 9; IASA, Technical Committee, IASA-TC 04, 51-52.