Wavs, EDLs, mp3s and TC in devious conspiracy. Help!...

[reid]

Long winded background....

I''ve just finished a programme in which all the music cues were laid in to the edit as mp3s. A nasty problem cropped up when it came time to exchange the mp3s for their respective wavs prior to going to the dub.

According to the editor (who was using Avid Express Pro), his EDL saw all the mp3s as having a TC start time of 10.00.00.00, but the corresponding wavs (created at the same time in Logic, via a bounce) had varyingly different start times, making it impossible for his EDL to automatically place the files in the correct places. The wavs are exactly the same length as the mp3s, just their nominal start time was different. It took the poor bugger 3 hours to lay them in manually....

The question...

I can't find anything in Logic (or any other program) that allows the notional TC start time of an audio file to be set - is this possible to do? I'm half thinking this was probably an Avid issue, but it would be good to find a way to avoid this in the future.

Any ideas? Thanks!

[Dietz]

Broadcast Wave ("BWAV") is the way to go - this format has platform independent timestaps in its header. Any professional audio and/or video workstation should be able to read and interpret it.

[reid]

Thanks for the reply, Dietz.

Now that I've got off my arse and RTFM, I've found that Logic created wavs are Broadcast Wavs, and as such include a time code stamp. But nothing in the manual to explain what timing Logic derives this stamp from when making the wav file. The SMPTE start point of the arrangement? The offset SMPTE display reading? Another fine example of Apple's belief that too much information is a BAD thing in their manuals....

Anyone know where the timestamp is derived from, and is it possible to change it once the file has been created?

Thanks

[Dietz]

I'm not _that_deep into Logic, but usually, modern DAWs offer a "Update SMPTE Position"- or an "Update Time-Stamp"-command for any selected files. Most likely, Logic will have an opportunity to go the ProTools-"Regions"-route for that, which gives you the chance to have several virtual snippets made out of _one_ physical audio-file.

[Angelo Clematide]

As said, you have to bounce, or offline bounce the regions to Broadcast Wave. Logic 7 can do that, Logic 6 not. Broadcast Wave files include a high-resolution timestamp.

How to import, and move the regions to the record position in AVID, I don't know.

The handling in Logic is: "Move Region To Original Record Position" in the audio menu. I would guess Avid has a similar command. Also notice the SMPTE offset. The basics for Logic are on page 285 in the reference manual.

.

[Fred Story]

Unless I'm mistaken, the timestamp of WAV files bounced from Logic reflects the start time of the left locator. I don't believe it reflects the SMPTE View Offset time, but the actual SMPTE timecode location in the project. This is the way I've bounced when exporting music cue BWAV's for mix outside our studio, and it's always worked fine.

Good luck!

Fred Story

[Dietz]

@Angelo Clematide said:

[...]
The handling in Logic is: "Move Region To Original Record Position" in the audio menu. [...]
.

... but avoid doing this in Logic itself before exporting, as it would destroy the actual structure or your song/session/project.

[reid]

hey guys,

thanks for all the replies - that clears up a lot of confusion. Apparently the Avid being used assigns a default timestamp of 10.00.00.00 to mp3s (which don't have a timestamp of their 'own') - in the future I just need to be careful with the start times of my bounces.

Or even better, stop sending the editor mp3s and go straight for the full fat wavs. Saves a lot of messing around...