Inserting Multiband on the Master causes sync problem

BPB wrote on 5/20/2003, 4:48 PM
I'm working on a band video from RED ROCKS in Vegas 3. I have flown in and manually synced audio from a board mix (my video had no audio). I preprocessed the audio in soundforge and all is well. I decided to throw a multiband compressor across the Master fader as an insert to touch up the audio but the extra processing is throwing all my intricate hand syncing out of whack by a couple ms. This is my first project in video and with Vegas Video. I'm using 3 now and already have the 4.0 (not installed yet). This seems like a common problem (I hope) hoping to get good advise from experienced users. Also can anyone reccomend a good reference manual.
Thanks in advance
Bryan

Comments

BPB wrote on 5/28/2003, 11:30 AM
A follow up ..would prerendering the audio tracks (about 5) to stereo then locking them to the video allow me to add master buss audio effects without the audio and video drifting apart?
thanks in advance for replies
bryan
kameronj wrote on 5/28/2003, 11:42 AM
Couple of issues....hope this helps.

Manual - d/l the VV manual from the SoFo website. Great book for info. As well as this forum. These folks are pretty great with sharing information.

As for the unsyncing problem - unfortunately I don't think I grasp what you mean by "intricate hand syncing" being thrown out of whack. If you could clear that up - I may have some thoughts on it.

As for the last issue you brought up...uh, I forgot what that was , so let me get back to you on that one.
kameronj wrote on 5/28/2003, 11:46 AM
Oh yeah...I remember now.

It sounds to me since your video and audio were two different tracks to begin with - there may be a time difference with the files not anything the processing has done (per se).

What I could suggest is to render the audio the way you want - and then do the syncing.

It may not help much now after having already done the work - but it is definately something that you won't do again in this manner.

For me...I just procesed a video that took two days to render only to find out that I really didn't need to do it in the first place. So....it's a good thing I have a couple of 'puters to work on.

Hope that helps some. Perhaps others have a better piece of news for ya.
BPB wrote on 5/28/2003, 11:55 AM
thanks kareronj

I imported a stereo board mix of the band's music recorded on a Sony minidisc. I captured to Soundforge and edited the songs into separte wav. files. I had a video of the show with no audio given to me by the in house film crew. I imported the music into vegas 3.0 and aligned it with the video. It was amazing accurate over the course of an hour show. I edited out some dead air and such and the concert now plays through audio and video perfect top to bottom (i also added crowd noise etc.) My problem was when I tried to put a multiband comp. across the master audio fader to touch up the stereo master mix the audio delay introduced caused the audio to play behind the video..hoping to lock audio to video so I can introduce some audio effects without having to do it clip by clip in Soundforge.
Thanks
Bryan
kameronj wrote on 5/28/2003, 12:16 PM
Gotcha. That's what I was thinking.

It may work if you render the file together first....prior to adding the other audio events - and then take the rendered file and add the audio.

What I would do (assuming I had the time) would be to make a duplicate of the audio event and add it to the second event (leaving the first one intact). This way if after adding the audio FX it starts to fall out of synch - I still have the original audio event to fall back on.

That may help.
BPB wrote on 5/28/2003, 12:23 PM
thanks kameronj (spelling correct this time ;) )

I also did a dub back out to my mini dv camera to test play it . I'm thinking of just recapturing the dub with all my audio tweaks now synced to the video track then working on the new stereo file. One more question ..when I did my orig audio capture I did it at 44.1k in soundforge should i work in 48k for video projects?

Bryan
kameronj wrote on 5/28/2003, 12:50 PM
I don't think that's going to be a big problem.

Once you go to render it it will (or should) modify the audio stream to fit the project you are working on.

Hope that helps.

(No sweat on the wrong spelling...I didn't even catch it) :-)
thrillcat wrote on 5/28/2003, 11:50 PM
Actually, I've had issues with this that, since the only audio you're using is 44.1, set the file properties to 44.1. The default goes to 48. This may solve your problem quickly and easily. Your problem would definitely show up without any effects if you were mixing the 44.1 md tracks with 48 off the tape.