Mac OS X: Convert MKV DTS Audio to AC3

Posted: June 2, 2013 in Apple
Tags: , , , ,

LG Smart TV doesn’t support DTS audio. AC3 is one format that it supports.

MKV is just a container and we can easily edit/remove its contents by using some great free tools.

Below is my steps to replace the DTS audio track to AC3 in the MKV container. Thanks to

Tools you need: ffmpeg and mkvtoolnix.




  1. Open mkvtoolnix and add the MKV files. Confirm the audio track that you want to convert, usually we only convert the first audio track.
  2. Type the following command in Terminal. To open Terminal in Mac OS X, click Applications->Utilities->Terminal.
      /the/full/path/to/ffmpeg -i <INPUT_video_filename> -map 0:1 -acodec ac3 -ab 320k -ac 6 <OUTPUT_audio_filename>.ac3

    • -i refers to input file
    • -map refer to audio channel to convert (0:1 is the first audio channel)
    • -acodec refers to audio codec of the output file (ac3 is a fine one)
    • -ab refers to bitrate (320k is OK)
    • -ac refers to number of audio channels (6=5.1)
  3. After the output AC3 audio file has been created, click add in mkvtoolnix window
  4. Move the AC3 Audio up to make it the first audio track. You can also uncheck the DTS audio track if you don’t want it. I choose to keep it in case the AC3 audio has issues.
  5. Set the output filename and click Start muxing.
  6. Done

Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Google+ photo

You are commenting using your Google+ account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )


Connecting to %s