With the completion of the Phonograph at Edison's Menlo Park Laboratory on December 6, 1877 sound was essentially redefined as Edison had captured the ephemeral human voice and played it back.

In 1857 Edouard-Léon Scott de Martinville had recorded sound with his Phonautograph, however, Scott did not conceive or design his machine to speak back the recordings. (2)

Likewise, French poet and inventor Charles Cros had described his concept of such an invention that he intended to name the Paleophone (voix du passé). Cros submitted his concept in a sealed envelope to the French Academy on April 30, 1877 but it was not read in public until December 3, 1877. Cros never built a successful working model of his Paleophone.

The first public demonstration of a machine that recorded sound and played it back was Edison's Phonograph at the office of Scientific American in New York City on December 7, 1877. That demonstration resulted in the publication of "The Talking Phonograph," an article which explained how the phonograph worked but also included the writer's reaction to a machine that was changing the perception of ephemeral sound. "It is impossible to listen to the mechanical speech without his experiencing the idea that his senses are deceiving him."

The revolution of recorded sound in popular culture had officially begun.

Trumpeting the Revolution of the Phonograph! (3)

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