13. The non-transitory computer readable storage medium of claim 12 , wherein the first voice signature corresponds to a voice signature of a user.
12. A non-transitory computer readable storage medium containing at least one computer program, the at least one computer program comprising instructions for: receiving a selection by a user of an audio data file; loading a text representation of the selected audio data file; receiving a first voice signature and a second voice signature; identifying a first speech unit in the text representation, wherein the first speech unit is less than the entire text representation and is associated with dialogue of a first character in the text representation; identifying a second speech unit in the text representation associated with dialogue of a second character in the text representation, wherein the audio data file comprises one or more tags that define start and end times of dialogue segments associated with respective characters in the audio data file; receiving instructions to apply the first voice signature to the first speech unit; and applying the first and second voice signatures to the first and second speech units, respectively, to produce audio for playback.