From Berkeley Lab:

Berkeley Lab’s sound-restoration experts have done it again. They’ve helped to digitally recover a 128-year-old recording of Alexander Graham Bell’s voice, enabling people to hear the famed inventor speak for the first time. The recording ends with Bell saying “in witness whereof, hear my voice, Alexander Graham Bell.” The project involved a collaboration between Smithsonian’s National Museum of American History, the Library of Congress, and Berkeley Lab…

The Bell recording, which was etched onto a wax-on-binder-board disc, was made April 15, 1885 in the American inventor’s Washington, D.C., Volta laboratory. It was among a trove of recordings Bell gave to the Smithsonian before his death in 1922…

This isn’t the first time [Berkeley Lab’s] Haber and Cornell have made headlines for recovering sound from the distant past. Last summer, they digitally restored an 1878 St. Louis Edison tinfoil, revealing the oldest playable recording of an American voice.  And in 2008, they restored the earliest sound recording in history, a “phonautograph” paper recording made in 1860 by French inventor Edouard-Leon Scott.