There are many ways you can measure R128 LUFS in FCP X and deliver compliant content.
If you want to get really fancy there is this (expensive) LM6 plugin from Tcelectronic that will measure Loudness History, Momentary Loudness, True-peak Level, Program Loudness and Loudness Range (LRA) in a single view: www.tcelectronic.com/lm6-plug-in/
But things don't always need to cost an arm and a leg.
- Loudness Change from Videotoolshed (30$) is a standalone app that will analyze your audio file and export a mix with the volume set to the desired LUFS. If the app detects severe errors it will give you a report that allows you to do manual corrections: www.videotoolshed.com/product/68/loudnesschange
- And if you only need to export R128 compliant audio on an occasional basis, you can have it done online for a few bucks per program: auphonic.com
For my broadcast work I use PPMulatorXL which floats over the top of any app running on the Mac (including FCPX)
I position the vertical R128 meters to sit over FCPXs own meters to the right of the timeline.
The software is fed audio via an old Griffin iMic, which in turn is fed from the audio output of the edit suite via a spare mixer output. The iMic plugs back into the Mac, but the signal isn't used in the Audio preference, so there's no internal feedback problems. The same could be achieved with almost any audio interface. As long as you aren't interfering with the main system output, because that's what FCPX uses to output audio. So long as you can calibrate you system to your local standard then you'll be fine.
It is possible to fudge a software workaround using Soundflower and creating multiple audio paths inside the mac, but I find the iMic solution to be really reliable, plug and play.
When I play export ProRes masters back in Quicktime, PPMulator indicates their levels correctly too, as it works for any sound playing on the Mac.
How do you guys use efficiently loudness plugins in FCPX ?
I mean there is no master bus on which you can insert the metering plugin so that it reads your master output WHILE you can mix. You could create a compound clip and place it on the compound clip but that means each time you spot a loudness problem, you need to open in the compound clip, fix it, go back to the compound clip level and play it again form there ... or am I missing something ?
If I'm in the rare situation where I do need to tweak my mix as a whole (Mastering), I duplicate my Project. In the new project I put it all in a Compound.
Once there, I can apply a limiter, or compressor, or whatever to the Compound itself so I catch the full mix.
If there is one spot that's too loud, the Range tool allows me to select only that tiny bit of audio, and pull the level down only in that range (automatically makes the keyframes).
And with a Compound, using the Roles pane of the Timeline Index, I can open it up to show one lane for everything in each Role. I.E. a single lane for Dialogue, a single lane for Music, a single lane for Effects. I can then apply effects and keyframes on that level if needed.
But it will be nice when the rumored Roles Based Mixer is released.
That's what I thought too then ... too bad :-/
Especially if you cut a SFX heavy trailer for example. Cause most of the time you don't need nor want to reduce the overall volume, you need to dig in and reduce only the sounds that are too loud.
I really hope that Apple will implement a roles based mixer in the upcoming versions !
Then you are reducing individual clips, which is no big deal.
An sfx heavy trailer, setting levels on individual clips is your first step, even before you would touch a mixer.
I do this with Logic Pro X often, round-tripping from/to FCPX. You may want to look into that.
I feel it worthwhile mentioning that good output levels are only one piece of the puzzle. Good gain staging is the other.
Although it's been a bit of a buzz word the last year or two in music, the same principle applies to working with audio in general.
It's simple enough to understand and employ, however.
Fundamentally your audio wants to begin its life at a decent level, somewhere between -23 to -18dBFS for its over all levels and nothing clipping the meter. Every sound source should follow this consistently. This sets up a good playing field in which to build something rock solid on.
It's best to start your audio mixes I calibrate it like this. If you do it after the fact you will mess up all your projects volume levels and create more work for yourself. Considering this, ingest is the best time to calibrate all your audio source levels.
The second important part to this is with each audio process, the sound goes out of the plugin/filter the same volume as it went in. So if you start with your audio at -18 loudeness/rms, it should leave at -18. There are occasional exceptions to this rule, however. Most processes have an output level which you can use for this process.
Go by the meters in this case and not your ears, there are some processes that make the sound perceivably louder or quieter but measure differently on the meters. This is just a perceptual difference.
It doesn't have to be exact, close enough will do.
What all this ensures is you keep the fidelity of your audio path quite pristine and you're not inadvertently distorting some processes along the way. It also puts you in an excellent position to make your final output R128 compliant with less work.