As anyone who produces content for Broadcast or Theatrical Exhibition knows, there are very strict loudness requirements these days. EBU R 128, ATSC A/85 and CALM Act, and many more. And, as usual, there are lots of Meters and Plugins to help you achieve compliance. The problem is, they either don’t play nice with FCP X, and/or they are very expensive.
I was hunting around for a solution today that wouldn’t drain my bank account, and came across the updated version of Klangfreund LUFS Meter, a formerly free plugin with a lot of great features. I’ve tried a bunch of plugins for this, and LUFS Meter is by far the most user friendly. It’s of course designed for DAW’s, but works in FCP X on individual clips, or on a Compound Clip of your mix.
It’s really easy. Make a Compound Clip of your Project, apply the plugin and choose your setting. Play through once to get an analysis, press the “adjust to” button, export your cut and you’re done.
That said, this plugin is quite deep and has a lot of options and advanced settings, but the basic operation is very easy… Kind of like FCP X. 🙂
Press a Button to Make This:
Into This:

It’s simple, inexpensive and has worked well for me. I’ve found it to be very transparent sonically, though it’s always best if you start with a mix that isn’t as insanely hot as my example above. Even that mess sounded fine after processing though.
If you need to comply with loudness regulations but don’t want to spend a fortune, you should definitely check it out. The full version is $49, a “light” version is $25, and there’s a demo available with a 60 second analysis limit so you can try it out.
EDIT: OK, this thing is seriously cool… check the manual, but you can apply multiple instances of the plugin, and sync them together. So if you had 3 stems (compound clips) DIA/FX/MX, you can apply a LUFS Meter to each stem, assign them to the same sync group, and control them all at once from any instance. Normally all you need is 1 instance for a comped mix, but this feature could be very handy.
I also found out it’s been tested fairly strenuously with FCP X, unlike any other plugins like the that I’m aware of. If you need to deliver compliant mixes from FCP X, you need this.