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THE ANALOG AUDIO TAPE REFORMATTING PROJECT :
A NEW LEASE ON LIFE FOR OLD RECORDINGS
Don Bourdon, Archives & Library, Whyte Museum of the Canadian Rockies
In the wide range of life expectancies of archival records, the magnetic media family tends toward death at a regrettably early age. For that reason, many archives have identified these records for reformatting. At the Archives and Library of the Whyte Museum of the Canadian Rockies, the bulk of these records are sound recordings on tape and have been at the top of our reformatting list for years. The recordings consist of unique interviews, First Nations events and music, and a host of chatty conversations, some now fifty-three years old.
With CCA Preservation Management grant assistance, coupled with institutional contributions, the Archives & Library undertook the Analog Audio Tape Recording Reformatting Project this past year. Approximately 700 open-reel, ¼ inch and compact cassette audiotapes were analysed with respect to properties and condition and were reformatted by duplicating them onto CD-R's. There was a sense of urgency about this project, as 25% of the recordings predated 1960 and a further 33% were created between 1960 and 1969. The balance predated 1990. As such, most of the reel-to-reel tapes were on acetate rather than polyester base.
Each analog audio recording was copied, converting the analog signal to digital in the process, and captured on CD-R target medium, creating a flat transfer record or "artifact" (eg. one CD per reel-to-reel tape or cassette side). The original tapes and CD preservation masters were then stored according to the highest attainable standards.
CD-R was the most accessible technology available to our Archives and Library situation in the absence of IT support and dedicated and controlled server access. The life span of high quality CD-R's is comparable to audiotape, without the threat of mechanical damage. Obviously, this format involves no contact in playback. It is a superior target choice over digital audiotape (DAT), which already has longevity challenges and limitations inherent with thin tape stock. Due to its huge consumer acceptance, CD-R is "backwards-compatible" with respect to future hardware availability. Straight transfer to new analog recording tape would have involved prohibitively expensive target material and, potentially, an immediate loss in quality. Once copied onto CD-R, subsequent identical copies can be made without loss of sound quality.
Discussions with the National Archives of Canada (December 2001) and study of International Association of Sound and Audiovisual Archives IASA-TC version 2: The Safeguarding of Audio Heritage: Ethics, Principles and Preservation Strategy (September 2001) confirmed the approach taken in this project. We were assured by the NAC that this was currently the best available method for an institution of our circumstances.
A policy of "flat transfer," that is exact copying without any enhancement, was followed ensuring that both primary and secondary information was preserved. This "warts and all" approach does not negate the possibility of users enhancing sound quality down the line but the policy ensures a faithful record of each recording at a set point in history.
Professional quality equipment was used, the key ingredient being a stand-alone HHB CDR-850 compact disc recorder. Operating this equipment is not unlike using the familiar dual cassette deck, so the procedure is not daunting and success is dependent mainly upon setting optimum recording levels each time a new tape is copied. HHB CDR74 Gold discs were used and 44.1khz / 24 bit A-D technology employed.
Five different tape recording speeds were encountered, as well as various head configurations for different types of mono and stereo recording. Professional reel-to-reel tape recorders handled the most familiar speeds: 15, 7 ½ and 3 ¾ inches per second (38cm, 19cm 9.5cm per second). For these speeds, two low-mileage Revox B-77 tape machines were used, as each one had only two of the three required speeds. An alternate recorder, which became the technician's favorite, was a borrowed Technics 2 track 1500. It was much more forgiving of one particular tape stock (Scotch 3M "Language Lab", ca.1969), that the Revox balked at playing. A vintage Uher portable recorder, the pride of journalists in the 1960s and 1970s, was required for slower speeds of 15/16 and 1 7/8 ips (2.4 and 4.8cm per second). We acquired this machine from the estate of Jon Whyte and it was perfect for playing the tapes he made on it thirty years ago. An identical back up machine was found at the Rundle Memorial United Church rummage sale. Scrupulous head cleaning and de-magnetization is essential to maintain copy quality and prevent further damage to the tape originals.
Longevity of the original tapes was enhanced through copying them onto a new carrier. In the process, a consistent "played state" wind was achieved for each of the reel-to-reel tapes. Fast-forwarding and rewinding the reel-to-reel tapes had left many with the very uneven tape tension that occurs at high speed, an undesirable state for long-term storage. By retiring the original tapes, future mechanical damage has been prevented. Happily, most of the tapes were reformatted at a point in their lifespan when significant signal quality could be preserved. In a few cases, where an especially notorious tape stock was involved (Scotch 3M Recording Tape, ca.1985), extreme cases of tape "squeal" were encountered during playback, so that only one playing was prudent in order to salvage the signal content.
A gratifying level of problem solving resulted when overcoming the challenges presented by over fifty years of tape technology, the peculiarities of tape head configurations, and variations in recording practices. This project was ably undertaken by D. L. Cameron, Project Technician. Once the reels were in motion, she was able to complete a number of other collections management tasks. Don Bourdon, Head Archivist, supervised the project and performed trouble-shooting services for various tape players, necessitated by a variety of tape recording configurations and speeds. Now that we have completed the project, we would be happy to share our knowledge with other institutions and provide copy service on a limited basis.
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