Retro Thing has a very cool blog post on the earliest known audio recording, one that predates even Edison. You can hear the hard-to-make-out-clearly recording for yourself in MP3 format as well!
http://www.retrothing.com/2008/03/the-phonoautogr.html
yeah like a ghost singing.....
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The linked article lets you
The linked NY times article lets you compare it to a 1930's recording and you can then kind of hear the tune.
It sounds a bit creepy to me....
Erie!
Wow, hard if not impossible to make out and the pitch might be totally wrong but it is fantastic to hear someone sing from such a long time ago.

Editor / Pixelator - Armchair Arcade, Inc.
www.markvergeer.nl