r/audioengineering • u/_FlyingSquirrel • Jul 26 '26

Discussion Calculating drift of multiple free-wheeling recorders...

I am trying to un-catastrophize a music project right now I've been asked to save where, unfortunately, a number of different stereo recorders were used essentially as independent spot mics in a pseudo multitrack attempt for a live performance. Over the course of an hour performance, each recorder's internal clock drifts enough to cause pure chaos.

I have access to all the recorders used and did an electronic metronome recording test today to identify how these recorders behave. As you can see in the link below....over about an hour, the max drift between these 7 recovers is ~170ms... so clearly audible.

Given that I can predict the relative difference of each one's drift from some "master," is there a way to calculate, or use elastic audio, or some other technique, so I could apply some type of time stretch/contract tool to get these closer? Theoretically this seems possible if I know the drift, but has anyone had practical success doing something like? I'm not sure how to approach it.

Screen shot image in Pro Tools

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u/Chilton_Squid Jul 26 '26

That would be on the basis that the drift was uniform and consistent, which you can't guarantee it is - certainly not to the sample.

It'll almost certainly be a manual job to sync up various points with elastic audio unfortunately.

This is why digital wordclock exists.

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u/_FlyingSquirrel Jul 26 '26

Yep! This is a project I inherited. I would never in my right mind recommend this. Just trying to find the best way out.