From Au clair de la lune to Bruno Mars
April 9, 1860: Oldest Recording of a Human Voice Made
Édouard-Léon Scott de Martinville makes the oldest known recording of an audible human voice on his phonautograph machine.
The phonautograph is the earliest known device for recording sound. Previously, tracings had been obtained of the sound-producing vibratory motions of tuning forks and other objects by physical contact with them, but not of actual sound waves as they propagated through air or other media. Invented by Frenchman Édouard-Léon Scott de Martinville, it was patented on March 25, 1857.
The phonautograph transcribed sound waves as undulations or other deviations in a line traced on smoke-blackened paper or glass. Intended solely as a laboratory instrument for the study of acoustics, it could be used to visually study and measure the amplitude envelopes and waveforms of speech and other sounds, or to determine the frequency of a given musical pitch by comparison with a simultaneously recorded reference frequency.
Édouard-Léon Scott de Martinville, a printer and bookseller by trade, was inspired when he happened to read about the anatomy of the human ear in the course of his business. His phonautograph was constructed as an analog of the ear canal, eardrum and ossicles.
Scott created several variations of the device. The functions of the ear canal and eardrum were simulated by a funnel-like horn or a small open-ended barrel with a flexible membrane of parchment or other suitable material stretched over the small end. A pig bristle or other very lightweight stylus was connected to the membrane, sometimes by an indirect linkage which roughly simulated the ossicles and served as an amplifying lever.
The bristle traced a line through a thin coating of lampblack—finely divided carbon deposited by the flame of an oil or gas lamp—on a moving surface of paper or glass. The sound collected by the simulated ear and transmitted to the bristle caused the line to be modulated in accordance with the passing variations in air pressure, creating a graphic record of the sound waves.
One phonautogram, created on April 9, 1860, was revealed to be a 20-second recording of the French folk song “Au clair de la lune”. While it was initially believed to be the voice of a woman or adolescent, further research in 2009 suggested the playback speed had been too high and that it was actually the voice of Scott himself, singing the song very slowly.
Martinville’s Au clair de la lune