Hey Daniel , hi.
My current sub amp is 2x220/8ohms class AB , bryston acoustics , that goes deep into clipping at around -8db of avp"s vol. POA will not give anything more than 1 db of headroom , if i put it to drive the subs. QSC 4050 on the other hand is a 2x800/8 2x1400/4 , 1x4000/4 beast that can drive subs with confidence. We are talking serious power . The 15" subs that i have go down to 15hz -3db. And i think we all know how much power is required , if you want to have serious output in the lowest 2 octaves.
Actually increases logarithmically if i remember correctly.Hence the required power .
Limits established to be exceeded.