Two physicists have discovered a way to digitally map old, archived audio recordings and reconstruct the sound.

Two physicists have discovered a way to digitally map old, archived audio recordings and reconstruct the sound.

Four years after hearing a radio report on the challenge of preserving aging audio recordings, particle physicist Carl Haber's newfound method of rescuing the classics is music to archivists' ears.

Haber and a fellow physicist at the Lawrence Berkeley National Laboratory, Vitaliy Fadeyev, have found a way to digitally map the grooves in warped or damaged shellac records and wax cylinders, and play them back using a sort of virtual needle.

To do so, they use the same optical scanning method -- powered by a microscope and computer technology -- that physicists employ for measuring the journeys of subatomic particles.

The technique detects and filters any scratches, as well as clicks and pops from dust. It works with vinyl, too, though such records aren't fragile enough to need it.

Roughly 2.5 million music and spoken-word recordings are stored in the Library of Congress -- the project's sponsor -- but some are more than a century old and very delicate. Archivists risk further damage if they use a real stylus to play and re-record them.

"This marks a whole new direction for sound archiving," said Mark Roosa, the library's director for preservation. "They're reconstructing sound as we had never imagined would be possible, even if there are cracks in the cylinder."

The physicists hope their research will ultimately lead to a machine to preserve and enhance public access to sounds of history.

"Archivists want tools that will allow them to copy recordings with as little intervention as possible," Haber said. "It's starting to almost look like there could be a Xerox machine for recordings."


AP LogoCopyright 2004 Associated Press. All rights reserved. This material may not be published, broadcast, rewritten or redistributed.