Unlikely_Hero writes: The world's oldest known audio recording was played back for the first time today by a group of historians, audio engineers and scientists dedicated to preserving humanity's earliest sound recordings. The recording, made by Édouard-Léon Scott de Martinville in 1860, was made via an early phonograph called a phonautograph . Interestingly enough, Scott never intended to play the recording back. He intended to study the recording visually. The press release and an mp3 file of the sound are available .