Good afternoon. Although I do not have the D200's, I do use a home-brew amp based on the Hypex UcD 400 modules (which I understand are what are in the D200's in some modified form), with my Gallo Ref. 3.1's. I am very satisfied with this combination. It replaced an OTL/Quad 63 setup & I've never looked back (Yes, I know. I'm a Philistine). Near-field listening (~7') in a regularly-shaped room. Cordially,