Convert MP3 files to WAV files in iTunes
1.
Open iTunes.
2.
Select the track you want to convert to a WAV file. If you want to convert multiple tracks at once, it may be easier to create a new playlist and drag all the files you want to convert to the playlist. Creating a new playlist is especially convenient if you are converting MP3 or AAC files from different albums.
3.
Control-click (MAC) or right-click (PC) the track you want to convert and select ‘Create WAV Version.’ This initiates the conversion process.
4.
Search for the recently converted WAV files in your music library. be under the original MP3 or AAC file.
Tips and warnings
Converting audio files, especially MP3, to WAV or AIFF, can be done in almost any audio editor. The problem is that most programs cannot convert multiple MP3 files to another audio format in one step. Users are usually forced to convert tracks one MP3 at a time, in what becomes a tedious process. Fortunately, iTunes 9 solves the batch conversion problem by allowing users to convert an unlimited amount of tracks to WAV files in a matter of clicks.
Source:danspela.com