Another thing that's always intrigued me about it is that not only is it "analog", it doesn't even require electricity, at least for the audio portion. Sound waves could mechanically move a needle through warm wax which was spinning on a turntable at a regular rate with a hand-turned crank, across a screw drive. That needle would leave a spiral groove in a wax disk (or cylinder) that could be cast in metal using the "lost wax" method of casting. The reverse process would occur during playback, when the needle would read the data that was already recorded, and vibrate a mechanically amplified tympanum. I still don't know enough about the image recording process to say whether that could be done without electricity, but I know that its inception and the development of electricity happened very close together. There's no real reason I can think of why the Ancients could not have made something similar for recording audio and playing it back. The first phonographs did not use electricity!