Feature

Preserving the Sounds of History

Maintaining the aural history of New Zealand involves
considerable time and effort.

By Vivienne Fisher

Preserving history is important. It gives people an insight into the society, attitudes and technology of the past. At the Radio New Zealand Sound Archives in Christchurch, archivists are helping preserve history in the form of sound recordings.

The archives have stock consisting of gramophone records, normal acetate records, open reel tape, cassettes, digital tape, photographs and documents, all connected with the radio industry in New Zealand. Operating since 1956, they are one of only two professional sound archives in the country.

At Kent House in Christchurch, where the Archives are now located, sound recordings are stored, copied, preserved and catalogued. This selection of history is stored in a temperature- and humidity-controlled environment. The temperature is maintained at approximately 18^o C, with the relative humidity set at 35%. In this environment the deterioration of the archival material is slowed down, although previous damage cannot be reversed.

Copying is done from the original medium onto either DAT (digital audio tape) or open reel tape. These media are used because they have greater longevity, although as yet there are still some doubts as to the life expectancy of DAT. Stephen Riley, the head archivist, states that "DAT is not the permanent archival solution." However DAT is used for bulk copying because of the cost advantage. It costs $15 for a two-hour DAT tape as opposed to $180 for two hours of quarter-inch open reel tape. Open reel tape is selectively used for archiving material, as it has a guaranteed life of 50 years.

Deterioration after this time varies depending upon factors such as storage of the tape and its manufacturer. As yet there is no medium for storage of sound recordings which can be considered "permanent" in the sense of having a guaranteed life of over 1,000 gears.

Archiving this material is therefore a never-ending cycle of copying onto the most reliable medium which technology has to offer at the time, while taking into consideration factors such as cost and track record. The obvious problem of copying material onto a new medium is the fact that the equipment used to play that disc, tape or record also has to be kept. Repairing such equipment in the future may become a problem as technology becomes more advanced and parts for outdated equipment are no longer available.

As well as directly copying material, the Sound Archives also use a conventional analog technique to remove noise from monogroove records. Removal of noise is necessary as there is often damage to the walls of the groove or dirt in the groove. This causes the characteristic clicking or crackling sounds often heard when older records are played. Often an individual match has to be made to the groove dimensions, as early records had no set standards. The technique cuts down on this noise, masking the clicks and crackles.

Another problem dealt with is the deterioration of the medium upon which the original material is stored. Sound archivists are struggling with this internationally, not helped by manufacturers who are secretive about the compositions they have used in tapes and acetate records.

Open reel tapes, especially those used during the 1960s and 1970s, are subject to a sort of hydrolysis, known to Riley as the Vinegar Syndrome. Water reacts with the tape's binder glue, causing it to leach through the tape surface. The increased friction causes oscillation when the tape is played, making the tape squeal. The most common short-term solution to this problem is to "bake" the tape. This temporarily dries it, removing the moisture which causes the problems. The Sound Archives are hunting for a controlled convection oven to carry out this baking.

With acetate discs, the problems involve cracking. This is due to delamination of the plasticiser used, because of contraction and stretching of the disc. As the discs age and become brittle, they become more vulnerable to cracking.

The monitored environment in which the Sound Archives store the tapes and records can help to slow these deterioration processes, but it can't stop them entirely or reverse damage already done. The only solution is to copy the material onto another medium, such as DAT.

For the archives to be useful, it is necessary for the archivists to be able to find what users are looking for. To keep track of all their sound recordings, they now use a computer cataloguing system, replacing the card index system used up until 1987. The new computer database is quicker and more efficient. Riley saw a noticeable increase in productivity in the first three weeks after its installation. Information stored on the database includes a text description, a set of key words, the medium of the recording, type of programme, duration, a technical description and copyright,

Material is made available to radio stations for use on programmes. Other users of the archives include museum audio-visual displays, film makers, writers and researchers. Subject to copyright provisions, it is also available to the general public for a fee.

Vivienne Fisher is a freelance writer.