The following is a guest post by Carl Fleischhauer, a Digital Initiatives Project Manager in the Office of Strategic Initiatives.
During the first week of October, Kate Murray and I participated in the annual conference of the International Association of Sound and Audiovisual Archives in Cape Town, South Africa. Kate’s blog describes the conference. This blog summarizes a special presentation by two digital pioneers in the audio field, who looked back at a quarter century of significant change in audio preservation, change that they had both witnessed and helped lead.
The main speaker was Dietrich Schüller, who served as the director of the Phonogrammarchiv of the Austrian Academy of Sciences (the world’s first sound archive, founded in 1899) from 1972-2008. He was a member of the Executive Board of IASA from 1975 to 1987, and is a member of the Audio Engineering Society. He has served as UNESCO Vice-President of the Information for All Programme. In this presentation, Schüller was joined by his colleague Albrecht Häfner (recently retired from the German public broadcaster Südwestrundfunk).
Schüller came to the field in the 1970s. For many years, he said, the prevailing paradigm had a focus on the medium, i.e., on the tape as much as on the sound on the tape. This approach was more or less modeled on object conservation as practiced in museums, where copies are made to serve certain needs, e.g., reproductions of paintings for books or posters. But the copies of museum objects are not intended to replace the original.
For sound archives, however, there is an additional problem: the limited life expectancy of the original carriers. Magnetic tapes, for example, may deteriorate over time, or the devices that play the tape may become obsolete and unavailable. Therefore, sound archives must make replacement copies that will carry the content forward, extending the museum paradigm to embrace the replacement copy. But in years past, there was a catch: copies were made on analog audio tape and suffered what is called generation loss, an inevitable reduction in signal quality each time a copy is made.
As a sidebar, Schüller noted that, before the 1980s, the scientific understanding of the properties of audio and video carriers was not as well developed as, say, what was known about film. The first relevant citation that Schüller could find, as it happens, came from the Library of Congress: A.G. Pickett and M.M. Lemcoe’s 1959 publication, Preservation and Storage of Sound Recordings.
The 1980s brought change. There was increased interest in the chemistry of audio carriers, looking at the decay of lacquer discs and brittle acetate tapes, and the study of what is called “sticky shed syndrome,” a condition created by the deterioration of the binders in a magnetic tape. As the 1980s ended and the 1990s began, conferences began to focus on the degradation of the materials that carry recorded sound. Nevertheless, many archivists still sought a permanent medium–the paradigm remained.
The year 1982 saw digital audio arrive in the form of the compact disk. Some mistakenly expected that this medium would be stable for the long term. In the late 1980s, consumer products like DAT digital tapes (developed to replace the compact cassette) entered the professional world, even used by some broadcasters for archiving (not a good idea). In that same period, the Audio Engineering Society formed the Preservation and Restoration of Audio Recording committee, which brought together archivists and manufacturers of equipment and tape. This was, Schüller said, “the first attempt to explain that archives are a market.”
An important turning point occurred in 1989, the date of a UNESCO-related meeting in Vienna associated with the 90th anniversary of the Phonogrammarchiv. The meeting brought together the manufacturers of technical equipment for audiovisual archives and, Schüller said, was the first time that the idea of a self-checking, self-generating sound archive was discussed. This–what we might call a digital repository today–was a design concept that featured automated copying (after initial digitization) to support long-term content management.
The findings that emerged from the 1989 UNESCO meeting included some guiding principles:
- Sooner or later all carriers will decay beyond retrievability
- All types of players (playback devices) will cease being operable, partly due to lack of parts
- Long-term preservation can be accomplished in the digital realm by subsequent lossless copying of the bits
To over-simplify, the gist was “forget about the original carriers, copy and recopy the content.” For calendar comparison, the term migration and related digital-preservation concepts reached many of us in the United States a few years later, with the 1996 publication of Donald Waters and John Garrett’s important work Preserving Digital Information: Report of the Task Force on Archiving of Digital Information.
The years that followed the UNESCO conference saw slow and grudging acceptance of these findings by audio preservation specialists. A meeting in Ottawa in 1990 was marked by debate, Schüller said, with some archivists skeptical of the new concepts (“this is merely utopian”) and others arguing that the concepts were a betrayal of archival principles (“the original is the original, a copy is only a copy”).
The year 1992 brought a distraction as lossy audio compression came on the scene, with MP3 soon becoming the most prominent format. This led the IASA Technical Committee, meeting in Canberra, to declare that lossy data reduction was incompatible with archival principles (“data reduction is audio destruction”). By the mid-1990s, however, lower data storage costs removed some of the motivation to use lossy compression for archiving.
As these new ideas were being digested, it became clear to specialists in the field that digital preservation management would require automated systems that operated at scale. And here is where Albrecht Häfner added his recollections to the talk. He said that he had become the head of the Südwestrundfunk radio archive in 1984, just as digital production for radio was starting. He saw that digitizing the older holdings would be a good idea, supporting the broadcasters’ need to repurpose old sounds in new programs.
At about that same time, a trade show on satellite communication gave Häfner “a lucky chance.” The show featured systems for the storage of big quantities of digital data, including the SONY DIR-1000 Digital Instrumentation Recorder. Häfner said that this system had been developed for satellite-based systems such as interferometry used in cosmic radio research or earth observation imaging, and was marketed to customers with very extensive data, like insurance companies or financial institutions. “My instant idea,” Häfner said, “was that digital audiovisual data produced by an A/D converter and digital image data delivered from a satellite are both streams of binary signals: why shouldn’t this system work in a sound archive?” He added, “This trade fair was really the event of crucial importance that determined my future activities as to sound archiving.”
By the early 1990s, Südwestrundfunk and IBM were working together on a pilot project system with a high storage capacity, low error rate, and managed lossless copying. But when Häfner first reported on the system to IASA, he found that few colleagues embraced the idea. Some specialists, he said, “looked upon us rather incredulously, because they considered digitization to be under-developed and had their doubts about its functionality. Rather they preferred the traditional analog technique. At the annual IASA conference 1995 in Washington, there was slide show about the preservation of the holdings of the Library of Congress and I never heard the word digital once!”
Today, attitudes are quite different. Schüller closed the session by returning to the title the men had used for their talk, a slogan that spotlights the completion of the paradigm shift. We have moved, he said, “from eternal carrier to eternal file.” That’s a great bumper sticker for audio archivists!