By Michael Hopkin
Particle physicists in California are swapping bosons for basslines in a bid to breathe fresh life into the earliest sound recordings. A technique developed at Lawrence Berkeley National Laboratory allows researchers to create digital copies of old records without damaging the fragile discs.
The technique uses a light sensor, originally designed to track the paths of subatomic particles such as bosons, to capture images of the record's groove. A computer then uses these to reconstruct the recording, filtering out any background noise to produce a blemish-free digital version.
The researchers have already created a copy of Marian Anderson's 1947 rendition of "Nobody Knows the Trouble I've Seen", minus the scratches, pops and hisses.
Traditional remastering techniques involve playing records back using a stylus while making a digital recording of the result. But this can damage the delicate wax, shellac or vinyl originals, says Carl Haber, who is leading the new project.
The new method is non-contact. This means not only that discs can be preserved, but also that damaged records can potentially be salvaged. "If a recording is broken or cracked, it cannot be played at all using a stylus," he explains. "In our method, the separate pieces could be reassembled digitally."
Past performance
"It opens up a lot of possibilities," enthuses Mark Roosa, director of preservation at the Library of Congress in Washington DC. "This system will allow us to reclaim the past; it's a bit of archaeology."
The technique should be able to retrieve sound from even the earliest grooved recordings from the late nineteenth century, Roosa hopes. The wax or metal cylinders on which these recordings were made had been considered too deteriorated to salvage, he says.
Historians could even hear the words of Thomas Edison, the father of recorded sound, says Roosa. Edison is credited with making the first ever recording, when he recited "Mary Had a Little Lamb" into the mouthpiece of his 1877 invention, the tinfoil phonograph.
It is not only historians who could benefit; the new technique could act as a photocopier for recordings, Haber hopes. Converting the recordings to computer files such as the widely used MP3 format could open them up for public use without the need for specialized equipment, he argues.
"We are very interested in virtual replay methods," agrees Nigel Bewley, an archivist at the British Library in London. "Users could browse a catalogue, sit at a computer, put on headphones and listen to the MP3s," he says.
Non-contact reconstructions could be a huge benefit in preserving the British
Library's 1 million grooved discs and 10,000 cylinders, Bewley says. The library
has an armoury of record players, but many of the recordings are simply too
frail to play. "Scanning is the only method we have of recovering them,"
he says.
© Nature News Service / Macmillan Magazines Ltd 2004