Same. Voxengo Correlometer and Span Plus, and Youlean Loudness Meter. But at this point the first two are just confirmation for other plugins that are already doing a lot of helpful visualization.
The final visualization though is opening it up in Sound Forge Pro to look at the entire waveform at a glance… it easily reveals if you’ve Metallica’d your peaks, and sometimes hints that you can squash a bit more. Since I tend to go easy with compression/limiting (except for specific effect purposes on individual voices), I often wind up running through Voxengo OVC128 or Sound Forge Graphic Dynamics as a last step to squeeze a little bit more.
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