Multichannel Export

[Caldrumr]

I'm a bit new at this. I have used Audacity to extract audio tracks before, but I am currently working on a 5.1 project. I can see all of the channels, and when I export it, it shows the six channels, but I'm not sure how to tell which one is which. Do they automatically line up with the proper channel numbers, or am I somehow supposed to know which one is which, and apply them appropriately. I keep imagining center-channel sound coming through the subwoofer or something crazy like that. I'm not very experienced with this, so I figured I'd check first.
Also, if I were to want to split that to an eight-channel output, how would I go about doing that? Find out which tracks are side and rear and simply split it to two channels?

Thanks in advance!

[steve]

I am currently working on a 5.1 project.

Is this a project that you have started from scratch, or did you import an existing 5.1 file and are now editing it?
What format file do you want? AC3? OGG? WAV?

[Caldrumr]

I am currently working on a 5.1 project.

Is this a project that you have started from scratch, or did you import an existing 5.1 file and are now editing it?
What format file do you want? AC3? OGG? WAV?

I am extracting the Audio from a 5.1 DTS soundtrack on a video file (concert). I have been using FLAC. I'm just not sure about the channels.

[steve]

How do you intend to play it when it's complete?

[Caldrumr]

I was planning on playing the FLAC files from my computer (5.1 system) and my stereo system (7.1 system, hence my question about 7.1 channels). I was then going to convert the FLAC files to stereo MP3 files for playback in my car as well.

[steve]

The specification for Flac files is here: http://flac.sourceforge.net/format.html#frame_header
7.1 is not defined, so you'll need to check the specifications of your home system about that.

[Caldrumr]

Thank you very much for your responses.
I know which channels make up the file. My question was more along the lines of how to tell which ones are which. On the Advanced Mixing Options screen, streams aren't named. Do I have to just figure out which one is which, or is there a specific way to tell? For instance, in this file, the boxes are blank. On another DVD I did, they just showed the name of the file. How can I tell which stream is left, which is center, etc.?
Thanks again!

[steve]

As an example, let's say you have a 5.1 audio file.
When you import that file, Audacity will import channel 1 to the first track, channel 2 to the second. and so on.

By default, when exporting as a multichannel file, the channel mapper will allocate the first track to channel one, the second track to channel 2 and so on.

According to the Flac specification, a 5.1 Flac file should be:
1) left,
2) right,
3) center,
4) LFE,
5) back/surround left,
6) back/surround right

I don't know the channel assignments for other file formats, but Google probably does

[Caldrumr]

Okay, thank you! I appreciate you clearing that up for me. It was very helpful. I'll ask one more question, then I promise I'll stop bugging you. =-)
When I have all the tracks listed in Audacity, should I convert L/R and SR/SL to stereo tracks, or keep all six tracks as mono?
Thank you thank you!!

[steve]

I'd just keep them as separate tracks.

Note that Audacity does not support multi-channel playback so if you need to play back some of the tracks while you are working:
1) Click on the track name and from the drop down menu set whether you want it to play through left / right or mono (both) speakers.
2) Solo the tracks that you want to hear (Solo button on left end of the track).