I know this is an old question, but I've got a better answer for you.David's answer is correct that just concatenating the files will leave ID3 tags scattered inside (although this doesn't normally affect playback, so you can do "copy /b" or on UNIX "cat a.mp3 b.mp3 combined.mp3" in a pinch).i Tunes uses i Tunes library files and your i Tunes Media folder to organize and store your media.Some customers might have an i Tunes Music folder instead of an i Tunes Media folder.Change the “Remember Position,” “Gapless Album” and “Skip when Shuffling” fields to “Yes.” Select the “Info” tab in the “Multiple Item Information” window and enter relevant information, such as the author's name and the title of the book.
To join the audiobook files, use a program such as i Tunes, Free MP3 Joiner or Merge MP3.
However, mp3wrap isn't exactly the right tool to just combine multiple MP3s into one "clean" file.
Rather than using ID3, it actually inserts its own custom data format in amongst the MP3 frames (the "wrap" part), which causes issues with playback, particularly on i Tunes and i Pods.
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