What crucial capability did Edison's phonograph possess that the phonautograph lacked?

Answer

The ability to reproduce sound (playback)

The fundamental difference was the phonograph's dual capability of recording and reproducing sound, providing instantaneous auditory proof, which the phonautograph, designed only for tracing, could not do.

What crucial capability did Edison's phonograph possess that the phonautograph lacked?

#Videos

The First Man To Record Sound - YouTube

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