Sound Restoration Talk to Kick Off 'Year of Physics' Celebration

A Lawrence Berkeley National Laboratory physicist, who developed a way to digitally restore and preserve audio recordings using the same technology used to study subatomic particles, will be the opening speaker in a year-long public celebration of physics at Berkeley Lab.

Senior Scientist Carl Haber will talk about "Imaging the Voices of the Past: Using Physics to Restore Early Sound Recordings" on Wednesday, Feb. 16 from 5:30 to 7 p.m. in the Berkeley High School Library. The program, co-sponsored by the Berkeley Lab Friends of Science and the Berkeley High School Science Department, is free to the public.

His talk is the first of a series of events that will be staged by the Lab to commemorate World Year of Physics 2005, declared by the United Nations to celebrate the 100 th anniversary of physicist Albert Einstein's famous articles on fundamental physics principles - the theory of relativity, quantum theory, and the theory of Brownian motion. The U.N. and major scientific organizations will be sponsoring events throughout the year to raise worldwide public awareness of physics and honor Einstein's achievements.

Other dates in the Berkeley Lab series will be announced soon.

Haber and colleague Vitaliy Fadeyev developed a way to help restore and preserve the sounds of yesteryear by imaging the grooves in a recording much like measuring tracks in a particle detector. Their work could ultimately enable the Library of Congress to digitize the thousands of blues, classical, Dixie, jazz, and spoken word recordings in its archives. The mass digitization of these aging discs and cylinders will both preserve the nation's musical and oral history and make it accessible to a wide audience.

Haber's media preservation research takes advantage of Berkeley Lab's decades of experience developing ways to analyze the flood of data generated by high energy physics experiments. This work, conducted at accelerators throughout the world, requires the ability to image the tracks made by elementary particles as they hit detectors, and find these tracks amid a jumble of meaningless noise.

"We thought these methods, which demand pattern recognition and noise suppression, could also analyze the grooved shapes in mechanical recordings," says Haber. So he turned to a precision optical metrology system used by Berkeley Lab physicists to inspect silicon detectors destined for the upcoming ATLAS experiment in Europe, which will search for a theorized but never observed particle called the Higgs Boson. Instead of measuring silicon detectors, however, he programmed the system to map the undulating grooves etched in shellac phonograph discs. The images were then processed to remove scratches and blemishes, and modeled to determine how a stylus courses through the undulations. Lastly, the stylus motion was converted to a digital sound format.

The result is a digital reproduction of a mechanical recording, with each wiggle, bump and ridge in the recording's grooves faithfully captured, and each scratch ironed out. Examples of the work will be played for the audience as part of Haber's talk.

This work is considered an important new direction for preservation of collections of this type, which could be of benefit to libraries and archives everywhere. It will give the public greater access to thousands of old recordings, some so fragile that even the touch of a stylus could damage them.

The Berkeley High library, newly built and opened in 2004, is at the corner of Allston Way and Milvia Street.