How to decode AAC (.m4a) audio files into WAV?

"The easiest way to do this is probably with iTunes. In your preferences, go to Import Settings and choose ""Import Using"" to WAV encoder. Then you can right-click on any AAC song and choose ""Create WAV version."" You should be able to select a bunch of files at once and do this to them in bulk.

Nota bene: Don't forget to switch your import settings back to AAC when you're done, presuming you still want to be using it."

"To decode from AAC to WAV, you can use FAAD2, which is a command-line utility.

faad -o output.wav input.aac"

MediaMonkey should get the job done of converting the audio formats. ACC to WAV, OGG or MP3.
MediaMonkey should get the job done of converting the audio formats. ACC to WAV, OGG or MP3.

"If you are running Windows, try WinFF.

It can convert from/to MP3, MP3 (mono), MP4 (FS/WS), OGG, WAV, AAC, and many others."

"They seemed to have removed the option in Music (previously iTunes; Mac OS X Big Sur) to right-click and convert an AAC file to WAV.
I remembered I had VLC installed, however, and was able to convert a M4A to WAV (or MP3) in VLC as follows:

File -> Convert / Stream
Drop your AAC (M4A) media file (or click Open media... to browse)
Select from the Choose Profile dropdown list.

In my case, I didn't see one for WAV, but you can specify Custom and if you click the Customize button, you'll see options for WAV under the Encapsulation and Audio codec tabs, where you can also set bitrate, samplerate, etc. if you want.

Once finished, click Apply and, click Save as File to specify the output destination, and then finally Save to export."