Audio preservation: Balancing the new with the tried and true
- By William Jackson
- Aug 21, 2008
Archivists at the Lyndon B. Johnson Presidential Library and Museum expect the entire collection of recorded phone calls made during Johnson's presidency to be publicly available by the end of this year. But how will they ensure that this historical resource remains available 20, 50 or 100 years from now?
'Media manufacturers are not thinking 100 years out,' said Allan Fisher, archivist at the library and museum.
The recordings originally were made on Dictabelts, which record grooves on a plastic belt that can be played much like a record. The recordings have been duplicated onto digital audio tape, which are used to produce CDs for release. But magnetic tape, whether analog or digital, is notoriously fickle over time. It must be carefully maintained so that the magnetic media does not flake off, and the tapes cannot be stored and ignored. They have to be wound and rewound to keep them supple and playable, though not wound too tightly to avoid magnetic bleed-through.
'All of that is unbelievably labor-intensive,' Fisher said.
What about CDs?
'The jury is still out on CDs,' he said. 'Rewritable, don't even think about it. Some of the read-only disks are better than others, but it's too early to know. Nobody can guarantee that CDs will be usable in 15 or 20 years.'
It turns out that, for now, the original medium might be the best.
'It seems like the belts are going to remain very stable,' Fisher said. 'That platform is going to outlast magnetic tape. They get a little brittle, but with good climate control, they can apparently last a good long while.'
The problem with the Dictabelts is that the Dictaphone playback machines are disappearing. 'That is the Achilles' heel, long term,' Fisher said. Ultimately, the medium will outlast the playback equipment.
Fifteen years ago, the library scoured the country for Dictaphone machines and now has three of them in workable condition.
Keeping them working is something of an art. The library uses Mr. Wizard's Electronics, which has been named Austin, Texas's best appliance and TV repair shop nine times since 1995.
'There seems to be a society of audio gnomes who have and maintain old audio equipment, and Mr. Wizard taps into them for replacement parts,' Fisher said. Mr. Wizard recently found a stash of old cartridges for the playback machines, some of which he had to rebuild to fit the library's models.
However, optical scanning will eventually be the only way to recover old groove recordings, Fisher said. And ultimately, archival recordings will need to be transferred to a digital format. 'The advantage of digital in terms of preservation is that with the proper format, the data is independent of the original media.'
William Jackson is freelance writer and the author of the CyberEye blog.