Scarlet MHE-400 is the second of the Acustica "Homebrew" series: a line of plug-in sampled from hardware directly build by Acustica and based on the circuit diagrams of legendary vintage devices.
Scarlet is also the first Acustica stereo mastering equalizer.
Scarlet is practically identical to the original hardware as far as frequency curves (for certain aspects, it's even better). What's different here is the preamp color. Scarlet's pre is extremely clean and transparent, but if you're looking for the sound of an ancient counterpart equipped with its custom discrete op-amps, then you'd better wait for the original hardware based Acqua release later on.
We compared with another software recreation and we are close to an ideal circuit modeled plugin approach, we are finally doing something new: software which is finally superior to both a classic software approach (circuit modeling) and an existing hardware starting from a specific hardware design. The first would be sterile and will sound like a "plugin" cause the usual IIR and phase issues and the complete lacking of harmonic distortion introduced by real world components, the second would include too many mistakes and physical world limitations.