Blue Cat’s Protector is a 0 dB brickwall limiter, but did you know that you could actually set a ceiling value and adjust the maximum peak level of a mix?
First, insert the plug-in on your master channel. Then adjust the input gain and knee value so that the plug-in starts limiting just a little bit (no more than a few dBs) for peaks (not continuously).
You can now adjust the output gain that is actually the maximum peak value allowed by the plug-in (since it limits to 0 dB right before the post gain stage):
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The plug-in guarantees that the peak value of the output signal is limited to this ceiling value, hence its name!