Is going from recording to playback a trivial step? The article doesn't make this clear, but if this step is nontrivial, then Edison's contribution still seems

Is going from recording to playback a trivial step? The article doesn't make this clear, but if this step is nontrivial, then Edison's contribution still seems like a big deal. The article even seems to imply that the format he recorded the sound in was not amenable to playback.