Preservation of Obsolete Media: The Need for Managed Digital Storage Bruce Whisler Director of Music Technology Clemson University
Issue n Countless historical items in a variety of formats are endangered. n n n Tape Film Wax Cylinders Records Printed Materials
Potential Loss n Recorded sound n n n Is a unique form of historical documentation Has existed for a little over a century Can transport us back in time
Endangered Audio Formats n Wax Cylinders n n Early Records (shellac 78 s) n n Subject to oxidation Magnetic Tapes (including digital tapes) n n Subject to delamination, warping, cracking Magnetic Wires n n Subject to mold and chemical degradation CDs n Subject to delamination and physical damage
Endangered Formats, cont. n Greatest threats facing all formats: n n Obsolescence of playback equipment Lack of experienced engineers
Audio Preservation Strategy n Optimal playback of original item n n Item prepped, equipment calibrated Digitally capture analog signal n n 96 k. Hz sampling rate 24 bit word size n For a stereo audio stream this calculates to slightly over 30 MB per minute
Storage of Digital Audio Files n Unsatisfactory: CD-R/DVD-R n n n Burned vs. stamped (commercial CDs) Subject to failure modes Subject to obsolescence All CDs have errors Data format of audio CDs is not a true digital audio format n n CDs are multiplexed and interleaved Broadcast Wave File (. bwf) is the preferred archival format
Digital Storage, cont. n Better: Redundant hard drives in two geographically separate locations n n n Drives can fail – routine monitoring essential Wide geographic separation desirable Cool, dry storage desirable
Digital Storage, cont. n Best: Digital Mass Storage System n n n Automated/Self-Checking Redundant Migrated as necessary
Storage Requirements n n 350 PB World Wide 50 PB for all audio in USA?
Challenge n n The NEH is awarding funds for digitization projects Land-Grant and other major universities need to help provide the storage n Harvard and Indiana - Sound Directions Project
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