Not syncing

Ok not sure why this doesn't work.

I have a 2 hour dance recital with 2 cameras. Used a shotgun mic on one cam to pick up audience applause and music which of course is very hollow sounding. The other cam got a direct xlr feed from the audio board. During the recording the direct line was clipping on about half of the songs, audio engineer wasn't consistent. What I've done in the past was create a compound clip of both audio sources and mix them together there, so I get both the clean board feed and the audience together, then add that as a angle in a multi cam seq. Since the audio feed was the greatest, I got the songs the dance studio put together as aiffs, figuring I could add them to the compound clip to mix with the other audio. But when I select all the clips and select synchronize clips, it starts all the clips at 00:00:00 TC. I have the cam audio with about 30 connected clips all at the same spot.

I even tried it with just a couple of clips and still fails. When I do a multi cam sync, it syncs it up like a champ, I just can't mix the sources at the same time. Hopefully the 10.1 update with audio mixing will fix that (ahem...apple)

Has anyone else had a problem with just syncing clips?

Bad audio will interfere a lot with syncing.

Open the good audio clip into it's own Timeline (Right-click, "Open In Timeline). Select it and copy.

Open the video clip with bad audio the same way into it's own clip Timeline. Paste the good audio, manually get it synced. Mute the bad audio.

Now you should have a clip that syncs up well. Gain, you simply have to get good audio to sync with.

It's not that the audio is really that bad. What's strange is that I just tried it again using 7 clips and it synced just fine. What I noticed is that the sync engine for compound clips is significantly different than the engine for multi cam sync. I don't think I've ever had an issue syncing multi cam clips and I only use audio waveform sync. But just syncing in the event library for a compound clip hardly ever works.

Another question, can I create a compound clip, throw clips in it, than choose sync after the fact? The sync clips button in the menu doesn't gray out, but it seems to be useless.

I never have any issues sync'ing clips in the Browser. But then I was an audio guy from my very early childhood. I get very obsessive about audio quality. The only time I've seen sync'ing for dual system recording not work well is due to audio quality. Too loud, too soft, too much ambient noise at a level too close to the level of the target sound, etc. I'd have to hear samples of audio from each clip to know for sure.

Either way, Sync for dual system recording, one trick is to add a marker to the clips. FCP will then analyze the audio around those markers on those clips to compare, saving time and increasing accuracy.

Never trying to sync a compound clip, but my thought would be that FCP is going to still analyze all clips individually. I'll have to do some experiments.