Omnipressor.

Omnipressor is Eventide's plug-in emulation of its own dark-meter hardware from the 1970s, the first processor to make dynamics an effect in their own right. A single Function control spans the whole range, from steep expansion through compression and infinite compression to dynamic reversal, where loud passages come out quieter than soft ones. Attack and release times, limits on gain and attenuation, and a side chain input shape the response, from gentle levelling to aggressive, pumping effects.