Anybody know how to hook up the subwoofer with this combo???? I was just wondering because I might get the 6900 sometime in the future. Anyway, the 6900 has a LFE jack, but the manual and polk don't recommend using it. I dont know how to turn off the low pass filter on the onkyo (I'm not even sure if it has one) but I really don't want to wire the receiver to the sub then the sub to the speakers. Anyone know if it's ok to just hook up the sub with the LFE pre out and adjust the crossover through the 502 settings?