I recently purchased a DVD player and a 5.1 speaker set. The player has a built in decoder and has 6 RCA outputs. The set is composed of an amplified main unit that also works as a subwoofer, and 5 satellite speakers that connect to it. It has several stereo inputs (CD, TUNER, TV, AUX), plus a 5.1 one. Strangely, it has 6 RCA outputs: 5 for the speakers that came with the set plus one for a subwoofer. The set's manual say it is for THX system only(?). This was a very cheap solution and I am very happy with it. Nevertheless it lacks some bass power. Would it be possible to connect an active subwoofer directly to the DVD player? Or should I connect it to the set's main unit? If I do connect a sub to the main unit, should it be an active or a passive one? Thanks.