56

How would you convert (decode) AAC files into WAV format? (Or, if you prefer, how to decode & re-encode them into MP3 or Ogg Vorbis? But WAV is sufficient as I already have good tools for WAV ➔ MP3/Ogg conversion.)

I'm mostly interested in Mac or Linux solutions, but feel free to mention Windows ones too.

(Use case: I have some voice memos ("Apple lossless audio file"), recorded with iPhone, that I'd like to share in a format that's more common than AAC.)

Improve this question
1
  • 1
    Not to be pedantic, but if the file is "Apple Lossless Audio File", then it's ALAC and not AAC (which stands for "Advanced Audio Compression") -- not that it matters for any of the answers currently provided, all of which should be workable for either ALAC or AAC.
    – michael
    Commented Oct 24, 2017 at 8:32

8 Answers 8

Reset to default
10

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.

Improve this answer
2
  • 1
    Thanks, that works smoothly. Even if "import settings" at first seems a bit funny place for this setting. :) That NB is a good reminder indeed.
    – Jonik
    Commented Aug 18, 2009 at 0:41
  • Cannot find "Create WAV version." in iTunes (now called Music) and anywhere else. Can you be more specific where to find it?
    – tbrodbeck
    Commented Sep 13, 2022 at 13:54
74

On Ubuntu, I use avconv on the command line:

avconv -i input.m4a output.wav

You can also use FFmpeg with the same syntax, simply replacing avconv with ffmpeg.


This can do every M4A in a directory, combined with a for loop:

Linux:

for f in *.m4a; do avconv -i "$f" "${f/%m4a/wav}"; done

Windows (directly in the command prompt):

FOR %G IN (*.m4a) DO avconv -i "%G" "%~nG.wav"

Windows (in a batch file):

FOR %%G IN (*.m4a) DO avconv -i "%%G" "%%~nG.wav"


If you want a GUI, you may consider WinFF, which is a GUI for FFmpeg.

Improve this answer
4
  • 2
    Yup, works equally with ffmpeg instead of avconv
    – hennr
    Commented Feb 22, 2015 at 8:15
  • FWIW, I was converting from audio-only "m4a" to "opus" and the output contained an empty video stream for some reason. I had to add -vn to avconv to force audio-only output.
    – Petr
    Commented May 7, 2016 at 20:04
  • 1
    As of 2017, ffmpeg would likely always be used/preferred over avconv, after a weird period of drama in the history of those projects. Also, m4a is a container format, actually identical to mp4 (it was only introduced in order to assist operating systems that used file extensions to determine what program to use to open the file). So, using ffmpeg ...-vn ... to disable video output would be a good idea for consistent results.
    – michael
    Commented Oct 24, 2017 at 8:40
  • What Ubuntu package contains avconv? I don't appear to have it, repo doesn't have a package with that name either.
    – Joseph Garvin
    Commented Aug 24, 2020 at 23:47
29 
ffmpeg -i inputFilename.m4a OutputFilename.wav

check out further ffmpeg commands to convert directly to a desired format (mp3 / ogg / aac, ..)

Improve this answer
20

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

faad -o output.wav input.aac
Improve this answer
2
  • 1
    I was going to upvote this answer as it is the most straightforward one, sadly FAAD2 doesn't support the Apple Lossless (FLAC) format. To convert this format you'll have to use FFmpeg instead.
    – Gras Double
    Commented Nov 19, 2017 at 17:46
  • 1
    Apple Lossless is ALAC, not FLAC. FLAC is free and very well supported in almost all tools.
    – tzot
    Commented Feb 5, 2019 at 10:04
2

In Ubuntu, I used SoundConverter (just search for it in Ubuntu Software Center).

Improve this answer
1

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

Improve this answer
2
  • 1
    Thanks. For the record, MediaMonkey seems to be a Windows-only app. Some more relevant info: "MediaMonkey also allows automated conversion from all supported formats to MP3, OGG/Vorbis, WMA and WAV with total control over quality and volume settings. Registration to MediaMonkey Gold is required for converting more than five files to mp3. Alternatively, the user can replace the included MP3 encoder library with a free one, such as LAME." en.wikipedia.org/wiki/MediaMonkey I personally appreciate the possibility to use LAME.
    – Jonik
    Commented Aug 18, 2009 at 0:31
  • Yes, it is windows-only as far as I know. I've got my copy hooked up to LAME, and I've converted WAY more than 5 files to MP3 with the free version.
    – Electrons_Ahoy
    Commented Aug 18, 2009 at 2:16
0

If you are running Windows, try WinFF.

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

Improve this answer
1
  • Note that WinFF is only a GUI for the renowned cross-platform CLI ffmpeg.
    – Nino Filiu
    Commented Jul 2, 2019 at 22:31
0

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:

  1. File -> Convert / Stream
  2. Drop your AAC (M4A) media file (or click Open media... to browse)
  3. 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.
  4. Once finished, click Apply and, click Save as File to specify the output destination, and then finally Save to export.
Improve this answer

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .