What is the immediate functional difference between the Phonautograph and later recording devices?

Answer

It lacked the ability to reproduce the sound it captured.

The Phonautograph made a permanent inscription of an acoustic event but could not play it back; this ability to capture and replay immediately defined subsequent inventions like the Phonograph.

What is the immediate functional difference between the Phonautograph and later recording devices?

#Videos

The First Man To Record Sound - YouTube

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