http://www.theatlantic.com/technology/archive/2012/10/scientists-recover-the-sounds-of-19th-century-music-and-laughter-from-the-oldest-playable-american-recording/264147/
Last night at the GE Theatre in Schenectady, New York, an audience of about 200 people sat and heard the sounds of a someone playing the cornet, a man laughing, and a recitation of “Mary Had a Little Lamb” and “Old Mother Hubbard.” It is believed that this event was the first time that any public audience had heard those sounds since they were captured by a Thomas Edison-invented phonograph in St. Louis in 1878.
For years the audio was trapped on the piece of foil you see above. There was no device that could play it and even if there had been, doing so would have likely ruined it. This summer, at Lawrence Berkeley National Laboratory in Berkeley, California, physicist Carl Haber and his team were able to create a 3D picture of the foil whose topography could then be translated into sound using techniques of mathematical analysis and physical modeling to calculate how a needle would have played the recording. They were able to do so “without physically having to touch them,” he explained to me. “And that’s kind of the key issue, because these things are so old and fragile and torn-up, broken, and delicate that in many cases it just would not be possible to play them back in any of the more standard ways.”
Once they had the scan and had processed it, here’s what they heard:
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