Particle physics and antique recordings may seem to have little in common. But at Lawrence Berkeley National Laboratory, a U.S. Department of Energy (USDOE) lab doing unclassified research in northern California, there's a definite connection. Scientists there have been harnessing the tools of their trade to recapture and preserve historic sounds on old disks and cylinders too fragile or damaged to play any other way.
Lawrence Berkeley scientists Carl Haber and Russian-born Vitaliy Fadeyev usually build and analyze precision equipment designed to detect quarks and other subatomic particles. But recently, they've been turning their high tech tools to more low-tech ends. They've been experimenting with ways to salvage recordings like this badly scratched Edison cylinder from 1912.
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Using what looks like a high power microscope hooked up to sophisticated computer equipment, they've been able to make that scratchy recording sound like this.
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The problem facing Mr. Haber and Mr. Fadeyev is that many early recordings were not necessarily meant to last. Many of the wax cylinders from a century ago are already in an advanced state of decay. Acetate transcription disks used to record early radio programs, were never meant to stand up to repeated play. And even mass-produced records, old 78s, through the wear and tear of many decades have become scratched, brittle or even cracked and broken.
The Library of Congress in Washington D.C., has one of the world's largest collections of recorded sound, overseen by Sam Brylawski. He says many of those recordings are currently unplayable and no one knows what's on them. Mr. Brylawski says the new technology developed at the Lawrence Berkeley lab has the potential for revealing one-of-a-kind recordings of significant historical value.
"There are some famous recordings that were made that are now lost and I don't think they're at the Library of Congress but we hope they are somewhere. Mark Twain is reputed to have made a couple of cylinders, but no one's ever heard them."
The possibility of hearing one of 19th century America's best-known authors and other lost treasures is so compelling that the Library of Congress is now funding some of the research.
At the Lawrence Berkeley Lab, Mr. Haber demonstrates a Smart Scope - the precision scanner the scientists use to take high-resolution pictures of the grooves in the records.
"...So this is a table and it moves under the control of a computer and the computer knows where the table is because it's got encoders. And this is a camera and some optics. So it can then capture an image of whatever is on the table...."
After the images are scanned into the computer, the shape of the grooves is analyzed with software that can recreate the original sound waves etched into the record's grooves. For that to work, the researchers had to understand both the geometry of the grooves and the movement of the stylus that actually translates the impressions on the record into sound.
"We're not putting a needle on it anymore. It's a virtual needle. So we have to understand how to model the behavior of that needle as if it was a real needle."
In addition, the software can "smooth over" scratches and dirt, leaving audio just as it was in the original recording. By combining this technology with commercial sound shaping techniques, the old recordings come close to sounding as they might have sounded in the recording studio. As an example, the Lawrence Berkeley Laboratory researchers demonstrated their technology on a 1950 recording by the folk group, The Weavers.
In addition to the archeological thrill of restoring lost records that are decades, or even a century or more old - the Library of Congress also sees the technology as a way of fulfilling its mandate to make its collection of recordings more accessible to the public… from the beginnings of ragtime music, the history of jazz and blues to classical music, poetry and news broadcasts. Mr. Brylawski says there are also recordings made for the many ethnic groups coming to the United States during the early 20th century.
"Ethnic recordings of almost every ethnic group that was significantly represented in the United States. Those groups were recorded by commercial record companies - Victor, Columbia, etc. for sales back to those communities in the United States. Ukrainian recordings, Polish recordings, Jewish recordings, Irish recordings. Some of these materials are scarce, because they didn't sell a lot in the very first place. And those are the types I'd like to see the public given more access to."
The ultimate goal of the research underway at Lawrence Berkeley laboratory is to develop an automated device that would allow librarians and archivists, rather than physicists, to scan in their collections for easy public access. Vitaliy Fadeyev and Carl Haber expect to have the first version of that machine ready in about a year.
For our world, I am Peter Jon Shuler in Berkeley, California.
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