Hi Mike
I'm not Ronny, what a wonderful and helpful person he is, but here is my take.
Just starting to use the latest versions of FCPX and LPX; both now 10.4, but I have been a live sound engineer for over 40 years and been doing videos for around 30.
The improvements in both programs are pretty amazing. I wonder if you can't now do all of your audio editing and sweetening inside of FCPX. Big improvements in the last few versions. Hard to give advice without knowing or seeing the media and project. But here's my 2 cents worth.
The key to good audio both inside FCPX and to exporting to LPX is the use of "Roles" and "Subroles" or components. The actual transfer to LPX and back again is in using "Export as XML", not iTunes.
Roles and XML has been vastly revamped and made better. Earlier versions had some real issues and you really needed to use a 3rd party program like XtoPro to bring a project into Logic and retain all your data structure. Now mostly not needed. Can't speak for Ronny, but this may be what he meant.
Making lots of assumptions from what you posted, I might make the Multicam clips, select the best audio "track" clip as the monitoring angle, sync to that, make all my angle selections, cuts and get the final shot assembly done, assign roles and sub-roles to all audio, change the audio to dual mono (not stereo) in the inspector. Make a duplicate of your project for security, Now you can either create a new compound clip of all clips, select all, new compound clip, then export XML. You can export only audio or both video and audio to folder or desktop. Then open LPX and under file, open audio file and import your project with or without movie. Best to select the movie sample rate, typically 4800. This should preserve each role/subrole as a separate track. Now you can work on it in LPX. You can import the movie for a visual aid if needed. Export back out and import to your project in FCPX.
Or you can just work on audio inside of FCPX. Once you have a compound clip in the timeline, you can double click the clip expanding the clip showing the "Roles" disclosure triangle for sub-roles, then in the "Inspector" turn off and on the various audio, adjust volume, apply effects like EQ, compressor, etc… to each Role or sub-role(component). The Timeline Index is definitely your friend here for organizing. Not a bad idea to color code your various roles. Here "lanes" are the closest you come to "tracks" in FCPX.
Not sure about your project, but this may be fine for your workflow. Double clicking on the audio meter in small info window will expand the meters so you can check the levels. The range tool (letter "r") allows you to quickly select a range and adjust the levels while adding multiple keyframes to the selected range. Makes boosting or attenuating sound fast. Really wish Apple would include a Mixer or allow the use of the LPX remote app as a directly linked plugin/extension.
OK, some resources.
Apple…
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support.apple.com]
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support.apple.com]
Ripple Training…
Lots of good info including their free intros to FCPX 10.4 and 10.3 so recommend to watch the series.
This one is a little old but good for organizing roles… [
www.youtube.com]
Newer Under 5 for working with Logic… [
www.youtube.com]
They also have vids on Logic itself.
Learning Logic I like the series by MusicTechHelpGuy. Josh has multiple good videos, many are based on LPX 10.2, but still I think some of the best on YouTube. He has newer vids on the latest versions so check out his channel…
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www.youtube.com]
Well Mike best of luck to you. Just gets you started, happy editing.
Hope this Helps, Greg