You can connect the DVD player's L and R audio out to the L and R line level input of a powered sub. But all you'll get is summed L + R low pass signals for the bass frequencies. And, Philander is right, since you'd be using the line level inputs, you cannot use the speaker level output to drive satellite speakers. The DVD player's LFE out is the one you should connect to the powered sub, in the absence of an HT receiver.