I used to run an ADA rig with the MB-1 preamp and the B500B 500W bi-amp power amp. I sold the power amp ages ago, and haven't gigged much since then. I kept the MB-1 because of its amazing distortion - solid state "edge" and tube (2 x 12AX7) overdrive. Think "Anesthesia - Pulling Teeth". I'm getting a new Mesa Carbine M6 combo amp, which has a 12AX7 tube preamp. What are the thoughts on using the MB-1 with this amp? I'm trying to follow the "keep it simple" rule, and I doubt I will make much use of the other MB-1 functions (parametric EQ, compression, chorus), as the Mesa amp shapes the sound nicely, and the MB-1 compression audibly muffles the sound quality. Is "stacking" tube preamps a good idea, or at least a "no harm" situation? If I discontinue using the MB-1, is there another effects generator / preamp or pedal out there that creates amazing distortion at bass frequencies?