I don't know of any way except re-import the audio in a 5.1 project.

OK, I figured it out how to do this. If you only have a single audio track, it is not too hard. If I had Camtasia installed, I'd do a quick video tutorial, but I don't, so here is the text version.

How To Convert An Existing Stereo Project to 5.1This 10-step tutorial assumes you have video which contains 5.1 audio. Many modern consumer and prosumer cameras have the option to record audio in this way, as do many sound recorders, such as the popular "Zoom" recorders. However, if you put these clips into a project set for "Stereo" audio, only the stereo audio embedded in these clips will be used. This tutorial shows you how to later convert an already-edited project from stereo to 5.1 audio.

1. Change the Project Properties of your existing, already-edited project from Stereo to 5.1 (you'll find this in the Audio tab).

2. Drag an existing 5.1 video/audio clip to the end of the timeline, but drag it so the video from this event is below both of the existing tracks. This will create the requisite surround tracks, along with an additional video track (which we'll delete in a moment). Pay attention when you do this so that you end up creating all new tracks, while keeping your existing stereo track. This will let you mute the stereo track when you want to use the 5.1 mix, or mute all the surround tracks when you want to keep the stereo track.

3. Label each of the new audio tracks. This makes things easier when you create the audio for each track. For the usual 5.1 audio, the first track should be labeled "1/2"; the second "3", the third track "4", and finally the last track "5/6". You can come up with any other labels you want, but these match the language Vegas uses.

4. Delete the video track that was automatically created when you temporarily dragged the 5.1 event below and to the right of the existing timeline. Then delete that temporary event's audio.

5. Now the fun starts. Put a marker at the beginning of the first audio event on your original audio timeline. This is an optional step and is only needed if your video precedes your first audio. Now select the first audio event, right-click, and choose "Select Events to End." Now press the "U" key to ungroup all of these events from their video and then press Ctrl-C to copy all of these audio events. Then, immediately press Ctrl-Z to undo the ungroup operation. All the audio events from your timeline (without the video), along with all the transitions and audio envelope points will all be on the clipboard.

6. Click on the first of the surround audio tracks that you created by temporarily dragging a 5.1 event to the timeline. Make sure the cursor is either at the beginning of this track, or at the marker you placed where the first audio starts.

7. Press Ctrl-V to paste all the audio events you copied in the step above. This should give you an exact copy, complete with transitions and all the audio envelope points, of the audio on the track above. You are almost finished.

8. Making sure that all the newly-pasted audio events are still selected (if not, select the first event and then right click on any event and choose "Select Events To End"), right click and choose "Stream --> Stream 2." If you have Vegas configured to display active take names (Ctrl + Shift + I), you will instantly see that the take displays "[Stream 2] [Channels 1/2]".

9. Select all the events on this first surround timeline, copy them, and then paste them to the track below. Repeat this paste operation for each of the remaining tracks. (If all events are selected, a quick way to do this is to press and hold the Ctrl key and then drag the events down to the next track).

10. At this point, all your surround tracks have the same "Channels 1/2" audio. The final step is to change the audio on each track. To do this, select all the audio on the "3" track, right click on any event, select "Channels" from the pop-up menu, and then select "Channel 3". Repeat for the two remaining tracks, selecting Channel 4 for the first of these two tracks and "Channel 5/6" for the final track.

You are done!


To all of you commercial script writers out there: (Excalibur, Vegasaur, Ultimate S, etc.):

If Channels and Streams can be scripted, this would be a nifty feature to add. You could also do the extra step of grouping this new audio with the same video event(s) to which the original audio was grouped. My tutorial does not attempt to do this because keeping track of grouping can get pretty complicated.

I believe that Stereo to Surround script from Gilles PIALAT does exactly what you described.

Thanks for the link to that script!

On paper, that script should do exactly what I want, but in practice, when using Vegas 10.0c, 32-bit under Windows XP, it throws this exception after processing only a few events:

System.Reflection.TargetInvocationException: Exception has been thrown by the target of an invocation. ---> System.NullReferenceException: Object reference not set to an instance of an object.

   at Stereo_to_Surround.Main.Start(Vegas myVegas)

   at EntryPoint.FromVegas(Vegas vegas)

So, for the moment, my manual method is what I'll be using.

While I made a mistake starting this project as stereo rather than 5.1, doing it this way actually makes life easier because I can edit with just one audio track. Then, when everything is working well, I can mute the stereo and create the 5.1 tracks, and then concentrate on cleaning up the 5.1 mix.

So a script that actually works would still be a useful thing. The problem with this script may be that perhaps it is looking for one of Gilles' proxy files, rather than real video files. I say this because the readme mentions his proxy script, and that this can be used after you have used that script.

[edit]See my post below for an update on why the script failed for me.

OK, the script does in fact work, but it doesn't like audio that is not grouped with anything. This goes under the heading of "be careful what you asked for" because at the end of my original post I said that if someone wrote a script, it would be great if the new audio events would be grouped to the original video event. This script does exactly that!! Nice.

However, the way this script is written, if you don't happen to group an audio event to anything, the script will fail. This happens a lot with the way I edit because I do a lot of "L" and "J" cuts, and also often continue audio from one event under the video from several additional events (e.g., cutaways or cover shots). I often don't bother to group these together. My manual method doesn't fail when events are not grouped, but as I pointed out in my first post, it also doesn't make any attempt to maintain grouping.

"You pays your money and you takes your choice."

If you don't have any grouping issues, then the script is definitely the way to go, and it works really well. Just for grins, after I figured out what was going on, I went through my original project and grabbed each audio event and moved it. If the video event above moved, I pressed Ctrl-Z to undo the move. However, if no video event moved, after undoing the move, I then selected the audio event, and any video events that were above it, as well as any other audio events that were under that same video event. I then pressed "U" followed by "G" in order to create a new group. After I did this for every audio event, I then ran the script and it worked perfectly.

Once again, thanks for providing the link to this script! It will be a real timesaver in the future, now that I understand its limitations.

But you're not really creating a 5.1 track here rather little more than duplicating the stereo track over again on the rear and center channels. The original 5.1 has been lost.

These 5.1 cams have 3 mic capsules (left, right, and center) so three tracks are actually recorded. The rest are of course calculated from the three tracks, but the point is that the REAL 5.1 track is still gone.

But you're not really creating a 5.1 track here rather little more than duplicating the stereo track over again on the rear and center channels. The original 5.1 has been lost.No, that is not correct. The media files I'm talking about have two "streams:" stream 1 contains standard left/right stereo channel; stream 2 contains a complete 5.1 mix, complete with left/center/right front channel; left/right rear channel; and the LFE channel.

So, the 5.1 most definitely has not been lost.

As to how that 5.1 track gets created, I actually do not know how many microphones are used. That is a separate issue.

"As to how that 5.1 track gets created, I actually do not know how many microphones are used. That is a separate issue."

From my old sony sr11

[IMG=http://i616.photobucket.com/albums/tt245/Bob_sanders/mic_zps46bdc09e.jpg]

3 mics are used in conjunction with "Dolby Digital creator" (3 tracks are record and the other tracks are calculated from those 3)

Interesting picture. I've used that camera many times, on loan. It is quite a bit older (2-3 years) than my CX700V. I couldn't find any information online about how many actual microphones my CX700V contains. I wouldn't be surprised if it uses a similar trick to your SR11.