I just found out this info. Works excellent on my Mac Mini. I have a bunch of HDTV shows I have recorded over the year - most all exported out as h.264/AC3 - .mov's. Also, I have some movies - ripped with handbrake - created h.264/AC3 .avi's ( then opened and saved from Quicktime as a .mov) -- so I can have it all imported into iTunes. ( for easy Front Row use and organization. )

Follow the steps on this site for AC3 pass-through on Quicktime. ( some small audio popping when it starts - but works great - just super cool )

http://geekwithfamily.com/2007/07/05/home-theater/howto-5-easy-steps-to-output-dolby-digital-from-quicktime-player/

If you need a plist editor - go here: http://www.versiontracker.com/dyn/moreinfo/macosx/22659

Thx to 123macmini.com forums - found the info here - http://www.123macmini.com/forums/viewtopic.php?p=90870#90870

Why would you need a plist editor? One ships with OSX.

Gonna have to try this when I get home. If I can get it working I may try and get Front Row installed on my G4 mini. Yes, I know the G4 mini doesn't have optical out. I'm curious to see if this will work with the Firewire Solo I have.

Why would you need a plist editor? One ships with OSX.

Yea. It's called Vi. :D

Hi Cclear,

I've followed the instructions to the letter, and I can't get it working. I have a mac mini hooked up to my audio reciever via optical cable.
With VLC, I can play .AVI, .MOV, .MKV with 5.1 AC3 audio passed through to be decoded by the reciever.

my prefs file is configured:
attemtPassthrough = 1
twoChannelMode = 0
I opened Audio MIDI Setup and set the Audio Output Format to 48000 Hz.

The result when I play a video with AC3 audio in QT or Front Row, is a clicking sound, or nothing at all.

This also seems to mess up VLC, but a restart cleared it up.

I really want to get this working, so if I need to post any more info, let me know.

Thanks,
--sdm.

Why would you need a plist editor? One ships with OSX.

Andrew67 - I didn't have one. Mabey it only installs if you install the Xcode stuff, which I didn't do.

pkscout - I don't think this will work without a digital Output. This is a total hack. It is somehow forcing the stream to output over the digital output.

sheldonmclean - I wish I had better news as well. It worked right out of the gate for me. Like I said - this is currently a hack, so not sure how stable yet. Worked for me last night fine though. My plist file also has a 3rd entry - "dynamicRange" Root with a number of 2. Also - you may have just mistyped up above -but double check your spelling on "attemptPassthrough" uppercase "P" as well. Not sure it matters... But other than that - works great for me. I tested a number of files.

Yea. It's called Vi. :D
So what you are saying is that the plist is a text file, and something like TextWrangler will work fine?

(vi was a piece of junk when I had to use it as a CompSci student in the early '80s and nothing has changed in that respect. Thank Richard Stallman for emacs in the old days and other developers for programs like TextWrangler/XCode/Eclipse today.)

Ted Todorov- you could edit the plist file with TextWrangler I suppose - BUT it is much easier with a plist editor.

Starting with Tiger, many plists are now binary files. A simple text editor will no longer suffice for many plists.

/usr/bin/plutil

"The plutil command obeys no one's rules but its own."

You can do a "defaults write com.cod3r.a52codec attemptPassthrough 1" in the terminal to change the preference if you don't have the plist editor.

pkscout - I'd be interested if it works with an external digital; afaik it's only been tested with built-in optical outputs of the AppleTV and PowerBook/MacBooks.

sheldonmclean - make sure that the digital out is set to 2ch-16bit as well

pkscout - I'd be interested if it works with an external digital; afaik it's only been tested with built-in optical outputs of the AppleTV and PowerBook/MacBooks.


Yup, it works. The instructions obviously aren't exactly the same, but they are in principle. When I open Audio MIDI I select the settings for the FireWire device and then set the format to 48KHz just like it says.

I'm watching Daredevil right now with full dolby digital. Very sweet. Now I may have to download the Front Row hack and try it again (AC3 passthrough was the only thing keeping me from doing this).

If Further stops in we might want to get him to update the sticky regarding AC3 passthough.

edit: I installed Front Row using FR Enabler. I feel like a kid in a candy store. Front Row goodness with AC3 passthrough. :D

This is outstanding news, does anyone know if this will work on an ATV?

If Further stops in we might want to get him to update the sticky regarding AC3 passthough.

Done. If anyone has any corrections or additional information, please post it here.

pkscout - I know what you mean! It is just so super cool to access all the HDTV shows and movies with FULL AC3 surround with front row!! We have been waiting way to long for this. :)

Clear, I get my HD captures from a tuner card (PCI). Do you have any idea if it matters where the material sources from? EyeTV, CATV box, HD satellite?

rezzy - Not sure what you mean. I use an EyeTV 500 - I capture QAM from Comcast. Gives me HD shows in a muxed MPEG2 format. I then use StreamClip to edit and then output an HD x264 video - and I demux the AC3 stream - and combine it with Quicktime.

That answered it....thanks.

Followed the instructions to a "T" on my mini, and can't get it to work. I ripped "The Number 23" from DVD to .AVI with AC-3 passthrough, then tried to play via Quicktime and Frontrow, and got "48KhZ" on my AVR, but no 5.1. Not sure if I'm ripping wrong, or if I missed something, but so far it's not working for me.

I haven't gotten it to work, but I'm only testing MPEG-2 and VOB files. Has anyone gotten those to work, or do they need to be MOV/AVI/DIVX?

I haven't gotten it to work, but I'm only testing MPEG-2 and VOB files. Has anyone gotten those to work, or do they need to be MOV/AVI/DIVX?

For VOB /MPEG2 I believe you need the MPEG2 component for Quicktime (which you have to buy from Apple) and a separate AC3 component (basically the A52 one built into Perian I think). It's not clear to me that a VOB will work the same as the MPEG4/AVI/DIVX files.