Multiple Music Libraries?
DeaDBeef allows you to manage multiple playlists.  The playlists are not those in a traditional sense (where you load pls, cue, etc) in that you select directories to populate the playlists.

If you were to store you files on your phone in such a manner: 


/sdcard/music/Lectures/..
/sdcard/music/Music/..


You could then create two playlists, loading the respective directories.  DeaDBeeF will ask you to install a plugins pack on first launch.  These plugins  allows you to play mp3s, as well as FLACs and cues.

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