MKV Mania: Adding A Secondary Audio Track with Another EAC3To GUI

by Damian on April 13, 2010 · 13 comments

in Guides

A few weeks ago I highlighted an excellent program called Another EAC3To GUI. AEAC allows you to convert your Blu Ray/HD DVDs into an mkv with full support for HD Audio, FLAC, and forced subtitles, all with the convenience of a few clicks of  the mouse. AEAC also allows you to edit the eac3to commands directly if you are feeling adventurous. As I have mentioned in other writeups, when I rip my Blu Ray/HD DVD collection I like to grab not only the original HD Audio track but also create a secondary AC3 audio track. Although currently AEAC does not support creating a secondary AC3 track as part of the Audio Options,  you can edit the eac3to command to do so. The one caveat is that by doing this you will have to remux all the AEAC creates files into an mkv manually using MKVMerge. Now for the fun part, let’s take a look at what needs to be done to create a secondary AC3 track.

Using Another EAC3To GUI:

- With AEAC open, select the playlist you want to use and click the “Command Line” button.

- The “EAC3To Command Line” Popup Box should now appear. In the top portion of the screen you will see the eac3to command line. In the bottom potion of the screen you will see the playlist with the tracks to be used checked off (based on the options chosen when first setting up AEAC).

- From the screenshot below you can see the eac3to command to grab the HD audio track “3:  “D:\Video\MyMKVFile – 3”. The “3″ refers to the Disc track # (looking at the bottom screen you can see that Track #3 is the TrueHD track).

- We want eac3to to take the TrueHD track and create an AC3 track. To do this simply copy the TrueHD command highlighted above, paste it into the Command Line right after the TrueHD command, and change the “.thd” to “.ac3″ (i.e. 3:  “D:\Video\MyMKVFile – 3 TrueHD.ac3″). It is that easy. Now eac3to will not only grab the original TrueHD audio track but also create a secondary AC3 track. By default eac3to will encode the AC3 track at 640 kbps unless you specify otherwise.

- With the changes made to the EAC3To Command Line, now click the “Add Batch” button. Under the “Output File” section you should now see your custom command line (with a note reminding you that you will need to remux separately and MKVMerge will not be used). Click the “Run all” button to run the custom command line.

- Once complete go into your work folder and you should now see all files that were output. From here you can use BDSup2Sub (if necessary) and MKVMerge to bring the files together into an mkv as I highlighted in this guide (skip the Clown_BD section).

Final Thoughts:

You may be asking if there is a pro or con to doing this method over the Clown_BD method I highlighted previously. The main benefit of this method is that AEAC will not only grab the forced subtitles but also convert to idx/sub. With Clown_BD you still need to use BDSup2Sub to accomplish this. Unless you need to adjust the idx/sub subtitles (such as adjusting the resolution), you can go directly to MKVMerge from AEAC.

Hopefully you enjoyed this guide and find it helpful as it highlights just one of the many custom command line changes you can make with eac3to, using AEAC as a front end. If you are interested in reading more about eac3to you can find an excellent guide here.

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Hi, my name is Damian, and I'm tech gadget addict! Although I always had some interest in technology, it wasn't until I got my EX470 and more importantly found, that my interest became an addiction. My goal, aside from world domination and to see the Mets/Broncos win another championship, is to set up the perfect digital home where all my media is available at the click of a button. When I am not writing for you can find me over at my blog at or follow me on twitter


Jeff C. April 24, 2010 at 11:59 pm

I wonder if this process could be used to add those missing commentaries from those lame Bluray releases that have the audio commentary on a separate DVD (Misery, etc) or missing (Total Recall)

I see why not. But I guess getting it to sync with the movie might be problematic since its from a DVD and not the BD. As long as there would be a way to offset the start timing prior to mux, it might make it easier to line up the DVD AC3 commentary with the BD movie stream.

Damian April 25, 2010 at 5:16 am

@ Jeff C.

Never thought of doing this. Using MKVMerge you can set a delay time for each audio track, so I think in theory it is definitely possible

Curtis June 2, 2010 at 12:25 pm

This will work for TrueHD but won’t for DTS Master as EAC3to only seems to be able to use the arcsoft decoder for one item per pass.
So if you are doing FLAC and want AC3, you have to go back in and covert the DTS Master to AC3 from the disc or use the FLAC track to AC3 (much faster).

Curtis June 2, 2010 at 12:27 pm

One other limitation to these automated methods is that you don’t get the chapter names. You need to be able to edit the .txt file before putting it into the final MKV wrapper.

Curtis June 2, 2010 at 12:31 pm

*edit – though I suppose you do have plenty of time when the conversion starts to go into the temp folder and edit the .txt folder there.
ok enough from me.

Damian Perez June 2, 2010 at 12:41 pm

@ Curtis,

You only have that issue if you have the Arcsoft decoder loaded on your PC. I noticed that issue when I was messing around with TMT but when I uninstalled everything went back to normal and I can create two audio tracks at once for DTS-MA.

Yeah, I have noticed that the chapter names don’t get thrown in as well. As long as I have chapters that can be used for navigation that is the most important thing. It would be nice though if this could be automated (I don’t know if there is a tool that would actually grab the chapter names, or if you are stuck just editing yourself)

Thanks for the comments

Jeff C. June 2, 2010 at 12:53 pm

There is this tool:

I am sure that this tool is probably just using mkvmerge tool and just automating it, so maybe the author of Another EAC3To GUI can be contacted to add or fix chapter adding. You will still need to provide the chapter file that can be obtained from the first tool I indicated in this post.

Curtis June 2, 2010 at 9:15 pm

@Damian – How do you decode and covert to FLAC w/o the decoder? I’ve not seen anything in avsforums or with this app that indicates another codec can be used.

@Jeff C – Very cool. I’ve just been cut and pasting from tagChimp (when it has the right chapters which isn’t always) into the .txt file created from eac3to export. Have to use it as BR’s seem to rarely have chapter names in the menu now but of course the DVD’s have them and in every case I’ve seen so far all the chapter stops are the same. Seems like this app could be added to the steps when selecting options.

Damian June 3, 2010 at 4:44 am

@ Curtis,

I don’t use FLAC which is why I don’t run into that issue with the Arcosft decoder. I retain the original HD Audio track.

Jeremy June 9, 2010 at 4:27 pm

You should use ’3: “D:\Video\MyMKVFile – 3 TrueHD.ac3″ -core’ so that eac3to takes the prerendered ac3 file that is already on the disc instead of conerting the thd to ac3.

Damian June 9, 2010 at 6:58 pm

@ Jeremy,

Good point. I got so used to doing the other method because of DTS(MA) I just ignored the fact that there is already an AC3 core track with TrueHD

Jeremy June 10, 2010 at 4:55 pm

DTS-MA always has a normal dts core so use of -core is advised in both cases. On HD-DVD the THD track wasn’t required to have AC3 3, but Blu-ray always has it.

Damian June 10, 2010 at 6:17 pm

@ Jeremy,

Grabbing the DTS core actually defeats the purpose of adding a secondary track for me. Most tvs cannot decode DTS for playback, but they can for AC3 which is why I choose AC3 as the secondary (example being the SageTV HD200 which does not downmix DTS to stereo so connecting the HD200 directly o a tv and trying to play a movie with a DTS track will result in no sound)

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