The oldest recorded human voice is a ten-second fragment of the French folk song 'Au Clair de la Lune'. It was recorded on 9 April 1860 by inventor Edouard-Leon Scott de Martinville (France). Discovered in 2008 by researchers in Paris, the clip was created on paper using a phonautograph, a device for recording sounds visually, without being able to play them back. The paper recording was analyzed by scientists at Lawrence Berkeley National Laboratory (USA), who used optical imaging as a 'virtual stylus', allowing the clip to be played back for the very first time.

Source: Guinness World Records