They are stappable as far as the user manual and kenwood says : " The KAC-9105D also has a Dual Mono Drive connection that allows you to strap two KAC-9105D amps together to power a single subwoofer—that’s 1800 Watts of power". and iv done the Big 3 and got 0 guage ran for my old set-up, i relize ill need a battery or two, but i have no problem gettin rid of them if i can w/o losing to much $$ on them to get a replacement