Acustica Audio Coral plugin is an all in one mastering channel. It includes a stereo and M/S Equalizer as well as a compressor with a plethora of options.
The Equalizer is based on a classic Baxandall configuration, a design which is highly prized for its clarity. Its smooth slopes easily allow broad musical corrections with minimum phase smearing.
Baxandall low and high shelves can be found in several hardware devices (although usually, they are present on a fixed frequency), while Bax middle (bell) filters are certainly few and far between.
The Equalizer is fairly straight forward, and I tend to use it a lot for adding air in the 25k range on final masters.
However, the compressor is much more complicated.
The detector section is what makes Coral so different from other compressors. It consists of 9 presets that model several rectifiers from different kinds of hardware. Each preset sets a different configuration of the attack and release curves: starting from the left the attack and release times increase (and are further split into individual attack and release settings).
Check out the video below for a full breakdown on this amazing plugin from Acustica Audio.