For being freeware, Audacity is a well-rounded Digital Audio Workstation (DAW). This is thanks to its open-source code and a dedicated programming community that continually enhances and extends the program's functionality. Audacity is a popular editing platform for podcasters, who typically create files in a 2-channel stereo file format. But with a few tweaks, this free software actually has the capability to produce multi-track surround sound audio files.
Due to software patents, Audacity does not natively support surround sound formats. They make it real easy to connect 3rd party extensions though. Under Preferences>Libraries, find the FFmpeg library and click Download. This will redirect you the the Audacity support page with links to the appropriate 3rd Party developers.
You can also follow this link to the Audacity support page.
Once you’ve installed the FFmpeg library, move over to Preferences>Import / Export.
By default, “Always mix all tracks down to Stereo or Mono channel(s)” is selected. Move this selection box down to “Use custom mix (for example to export a 5.1 multichannel file)”. With these settings selected, you are ready to begin.
Look at the example above. I have imported 4 tracks from a 4-channel surround sound recording I made with my Zoom H2n Handy Recorder.
To export this project as a surround sound file, go to File>Export Audio…
Under “File Type”, select a surround codec. For this example, we will use AC3 Files (FFmpeg)
A window like the one below will appear.
These are the mapping instructions for the surround sound file. The left-hand column includes the track names from your session. The column on the right identifies which speaker your track will be assigned to. By default, Audacity labels these channels as “Channel 1, Channel 2, etc.” This is not incredibly helpful if you don’t understand the AC3 file structure, but here is a cheat sheet for you to follow for a standard 5.1 surround setup:
You map the channels by drawing the strings from the left column to the right column. Since I only have 4 tracks in my example, I’ve mapped my tracks to Left, Right, Left Surround, and Right Surround. You delete connections by clicking on the string.
Hit OK once you are done the export the file.
You’ve produced your first surround sound file. The AC3 file is playable in Quicktime, Windows Media Player, and VLC.
What do you use Audacity for? Let me know in the comments below.