Unlike most early sound recordings, this one doesn't sound like ass. The reason is that Debussy recorded this with what was basically proto-MIDI.

From the Youtube page:
"The recording is a piano roll recording made by Debussy for Welte in 1913 (just three years after the work was composed). The piano rolls for Welte are amongst the most accurate we have, conveying the original performed dynamics, attack and pedalling rather faithfully, and when a good roll is played on a properly conditioned piano, the problems of dubious rhythmic bumpiness which infect many roll playbacks can vanish. This rendition seems as fine as we could hope for."

More info: http://homepage.mac.com/stevepur/music/debussy_plays.html