The heavier the banjo, the louder it is. Also, you might consider using heavier strings and adjust the action accordingly. I frail and fingerpick(not Scruggs style)a '27 Mastertone archtop, and string it;
12,14,16,26,11.
Even without the resonator(which I take off from time to time)it's still the loudest banjo I have ever played. Of course, it still weighs a ton, but it's worth it for the volume and the tone.

Mark Ross