Hi KP. Just noticed your new thread following our active-xover discussion. The only SS amps with some adjustment that I've heard of are ones which have a limited number of discrete gain levels that can be changed by the owner. For example, the Rowland amps, and the Gamut amps (there are others). I personally own a Llano Design Trinity hybrid amp, which has tube input/gain stage but SS MOSFET output stage. It accepts a wide variety of small signal tubes, and I can change its overall gain (and sound character) dramatically by rolling the (two) tubes. This amp might be a way for you to match your Rogue amp in a biamp situation; the Llano is more likely to blend with the tube amp, yet it provides more slam in the bass than many pure-tube amps (it's not very expensive either). Send me an email if you'd like more details.