For 2.1, I highly recommend using an AVR or pre-pro that can Equalize the subs. For example, Audyssey XT32 Sub EQ + DEQ.
I used to think that "Direct" and "Pure Direct" was best, but since I "discovered" Audyssey Dynamic EQ (DEQ), I will never go back to Direct and Pure Direct for music and movies. The improvement in the bass sound with DEQ is night-and-day, black-and-white astounding to me.
I use Audyssey Bypass L/R + DEQ. It bypasses Audyssey for the front L & R, but retains the Sub EQ + DEQ.