Topic: To shrink or stretch?

[Sloan Simpson]

I would just question the accuracy of those markers. Like I said, it's gotta be within +/- two samples. But who knows--it could do it. I might play around with it.

Just out of curiosity, why would you doubt them? I would doubt a human before I'd doubt ProTools 

[hoserama]

Because I know how precise they need to be. My main experience is time aligning with monitor mixes from different recorders. So it's generally a pretty clear soundboard-type pull. So any sort of issues with the time alignment and you start getting phasing VERY fast. However, the mixes are sometimes wildly different, so you need to use your common sense to figure out if a sync point is truly a sync point, and not just a similar looking wave form.

See the attached picture. Here's a time alignment that my friend did and I looked over. The dotted lines are the sync markers that he put in, because it looked like that was the start of the snare hit. However, if you look at the whole wave form, at least in that 1/50th of a second view, you'll see the dotted lines don't work. Instead, the correct sync point would be something like where the cursor is, and a majority of the peaks/valleys line up.

I don't really trust an automated program to not get tripped up on minor instances like that, and would end up checking every sync point before processing. That said--if it has some other functionality like ability to move/recalibrate sync points, it could be useful.

[bombdiggity]

^ Interesting example. 

Other than a truly mono recording aligning channels can be very tricky.  Apparently even with monitor mixes/SBD tracks. 

My experience in dealing with suboptimal L/R stereo sorts of configuration has been that you do need to look at the overall average (lots of reference points) since the discrete channels do not have the same perspective on every event within the overall soundstage.  Aligning an apparent "start" point would not necessarily be the proper alignment for the totality (as the above illustrates). 

The easier aspect is that a L/R stereo or a multitrack where all channels are on the same time clock means shrinking/stretching is not part of the equation, so there is an absolute alignment though slight offsets at almost any point along the timeline are likely (which provides the stereo image).   There's a lot more room for error in the realm of shrinking/stretching. 

[Sloan Simpson]

Elastic Audio does allow you to reposition the markers if you wish. When syncing a stereo room track with a stereo soundboard track I've never needed to though, it's worked perfectly.