Are you unhappy with the EVo, and why? What are your speakers? I have owned the Belles 350A as well as a pair of Evo200.2 amps, driving Maggie MG3.6 speakers. Very different sound. As usual in this game, + and - aspects for both amps. The Belles is fuller and more forward in the midrange, almost tube-like but not as liquid. The Evo is more refined in the upper mids & treble (also more extended on top), but the mids overall are more "reserved" (almost "distant"). In the bass, the Belles has more bloom and warmth while the mono Evo's are super tight... perhaps too fast. I went back and forth between these amps, never completely happy, but usually I prefered the midrange "body" provided by Belles. I've since moved on to the Llano Design Trinity hybrid (tube/SS) amps. If you're curious about Belles, I'd suggest you try to borrow the 150A amp to get an idea of the Belles "house sound".
