Many old audio documents are so fragile that playing them would destroy them. Construction by Mauricio Alejo

In early 2000, south of Oakland, California, a physicist stuck in traffic was listening to the radio. He heard Mickey Hart, a drummer for the Grateful Dead, say that the archives of the world’s aboriginal musics were deteriorating and needed attention. The bulk of the archives had been assembled between 1890 and 1940 by ethnographers using antique devices that recorded mainly on wax cylinders and aluminum disks. Many of the recordings had not been played for a number of years and had grown so fragile that the pressure of a stylus might destroy them.

Anything you can embed sound in you can scratch, crease, crumple, bend, break, tear, warp, or melt. Oil and dust and dirt get in the path of a stylus and deepen, widen, or distort a groove, making the stylus skip. Something, possibly mold, attacks the grooves on wax cylinders, leaving gaps that sound as if someone were banging a drum. On cylinders of Native American music, which typically features singing and chanting, this sometimes sounds like a phantom accompaniment. Wax cylinders were meant for businessmen to dictate letters on. After a letter had been typed, the cylinder was scraped clean with a tool the manufacturer supplied, so that another letter could be dictated, until the cylinder was used up. No one regarded the cylinders as permanent, and permanence wasn’t what the ethnologists sought. They wanted a version to transcribe—they wanted to read the text more than hear it.

The physicist, whose name is Carl Haber, works at the Lawrence Berkeley Laboratory, in Berkeley, California. There are essentially two kinds of physicists—experimental and theoretical. Experimental physicists test the ideas of theoretical physicists. Sometimes they observe peculiarities that theoretical physicists then name and explain. Haber is an experimental physicist. At Lawrence Berkeley, he is a member of the ATLAS Group, an international alliance of labs and universities that conduct experiments at the CERN collider, in Switzerland, where they discovered the Higgs boson, the “God particle,” in 2012. The ATLAS Group is huge. When a paper is published, Haber says, “it has more than two thousand names on it.” Haber specializes in the silicon detectors that line the collision chamber at CERN. The detectors are a little bigger than a passport, there are thousands of them, and they are arrayed like shingles around the chamber. They track the paths of subatomic particles in the aftermath of their impacts. Forty million collisions take place each second.

Haber regards himself as an instrument builder—that is, as someone who, after considering what device an experiment requires, designs the device and makes it or sees to its being made by a custom shop. To align the detectors at CERN, he had used a machine called a SmartScope, which “photographs the detectors in microscopic detail, then analyzes the images and the placement over and over again,” he says. This type of measuring is called optical metrology. The SmartScope had worked so well that Haber was drawing sketches and writing notes for new ways to use it. “When I heard Mickey Hart talking about sound recordings, I thought, Maybe I’ve been considering the wrong problem,” he says.

With the SmartScope, Haber had precisely positioned the detectors at CERN without touching them. He wondered what might happen if he used the machine to photograph the grooves of a cylinder or a disk that was too fragile to play. “I wondered, Could we somehow use optical metrology in some brute-force way to have the images interpreted as sound?” he says.

Haber went to Down Home Music Store, in El Cerrito, and bought a couple of 78s, “Goodnight, Irene,” by the Weavers, and “Whispering,” by Les Paul. The records were made from shellac, which is brittle; one of his colleagues dropped “Whispering,” and it broke. Thirteen people at Lawrence Berkeley have won Nobel Prizes, most recently in 2011, when Saul Perlmutter won “for the discovery of the accelerating expansion of the Universe through observations of distant supernovae.” Haber told colleagues that he wanted to measure the grooves on the phonograph records. A postdoctoral student named Vitaliy Fadeyev volunteered to help. “I remember colleagues who were just dismissive,” Fadeyev says. “Like basically not giving it enough thought—the actual value of it, the way you can save history and culture. How to do it, once you are told, and you are a physicist, it’s almost obvious. I find this is the case with all big discoveries. Once you are told the solution, it’s almost too simple. But, when you are trying to find the solution, you are scratching your head.”

Fadeyev scanned the groove of “Goodnight, Irene” as it unfolded over several of the record’s revolutions. Each revolution took close to forty minutes to complete. In all, he scanned about twenty seconds of music. A computer, following the path of the groove as if it were a stylus, converted the images to music.

“When I finally told Carl, ‘We can scan the record,’ he was shocked,” Fadeyev says. “He brought our senior engineer into the room, and that engineer laughed out loud. He saw an unexpected use of the machine—not measuring the object but getting the sound.”

Fadeyev’s scan “demonstrated in a very crude way that you could use a tool like this to measure a record and get sound, so I knew the idea had some merit,” Haber says. “It was laborious; it took hours; it was not practical. But I knew that, if we could make a machine that did this in a purposeful way, it could work. In physics, there are tons of brilliant ideas, but you have to make them work.”

Silence is imaginary, because the world never stops making noise. A sound is a disruption of the air, and it doesn’t so much die as recede until it subsides beneath the level of the world’s random noise and can no longer be recovered, like a face that is lost in a crowd. In past times, people sometimes thought that all sounds that ever existed were still present, hovering like ghosts. Guglielmo Marconi, who sent the first radio message, in 1902, believed that with a microphone that was sufficiently sensitive he could hear Jesus delivering the Sermon on the Mount, and in 1925 a writer for the Washington Post speculated that a radio was capable of broadcasting the voices of the dead. A radio transmits vibrations, he wrote, and the voices of the dead “simply vibrate at a lower rate.”

Except for an echo, only a sound that has been recorded can be heard again. A recording is a pattern of sound waves embedded in a medium. A person speaks, the sound moves a diaphragm, the diaphragm stirs a stylus, and the stylus traces a pattern analogous to the sound: an analog recording. (A digital recording converts the pattern of the waves into numbers.) Among audio preservationists, the few people who search for antique sounds and try to play them are sometimes called archeophonists; their field is archeophony. The oldest sound archeophonists have recovered is a proofreader of medical texts singing a folk song in Paris in April of 1860. As far as anyone knows, the proofreader, whose name was Édouard-Léon Scott de Martinville, recorded sound before anyone else did. Scott embedded his voice in soot on a piece of paper. He never heard it. The means for playing back sound weren’t invented until 1877, when Thomas Edison recorded himself on tinfoil. No one heard Scott until 2008, when Haber managed to play Scott’s recording. For his work in audio preservation, Haber received a MacArthur Fellowship in 2013.