ENGL r the sh*t great amps i am currently using the very effective but simple Fireball its a killer amp for metal real raw in your face punch .its hooked up to a std engl 4x 12 then a engl vintage pro 2x12 killer tone then add an eq in the loop and things start to get interesting.good luck with the powerball nice amp good features the secret i think with engl heads is to runthem through engl cabs with good speaker core wire anyways thats my 2 cents.