This showed up today, and holy shit, this thing kicks ass. It weighs only 4 pounds, is loud as hell, and the EQ expand switch acts somewhat like the resonance control on a 6505. (It instantly adds a bunch of balls to the low end.)
When set to the ‘in’ position this circuit will cut the mids by -4dB at 1KHz. This works well as a loudness contour when operating at low volume levels or adds tone when using it in a bass or guitar rack. When set to the ‘out’ position it provides a flat, normal response.
I'm running it with the Axe-Fx II (with the cab sims disabled) into my trusty old Recto 4x12 with V30s. It's a different feel than my FRFR Axe-II rig, and sounds absolutely killer. All the good juju of the Axe-Fx, plus air moving around like a normal cab. I was on the fence about this being the right idea (Selling the Mark V and having two Axe-II rigs instead) and it was absolutely the right decision. This setup rips!