Want to extract audio form video on Mac then convert to audio format files such as MP3, M4A, WAV, AAC, AC3, etc.? It's easy, what you need is a Mac video Converter. I recommend iSkysoft video converter for Mac. It provides you with very easy interface and very useful features such as batch conversion, trim audio, and merging added files into one file.

1Install and Run Video Converter for Mac

You can download it for free:

• Intel Version
• PowerPC Version

To install it, simply mount the .dmg archive by double-clicking it, and copy the application to your applications folder or wherever you want it.

2Load the videos you want to extract audio from

Click the "Add Files" button or directly use drag & drop to add video files to this program. This Mac video Conversion app supports batch conversion, so you can add multiple video files and convert them in one go

3Get audio from video on Mac OS X

Set MP3, AAC, M4A, etc. as the output format according to your nedds.

eg: If you want to extract audio from video to iPod, you need to select the output format as MP3.

If you want to export to iTunes as a ringtone (40 seconds long or less), you need to trim the audio to make its size smaller. Click Trim button to open the Trim window and trim the current title or chapter by dragging the Start Time slider to set the start time, and dragging the End Time slider to set the finish time. Then you can only get a clip of audio from video on Mac.

You can know more here: How to edit, crop, trim video files and capture pictures on Mac OS X ?