Eosone RSF-1000 setup help (1 Viewer)

This is going to sound like a totally newbie question, but, after years of dealing with HTIAB speakers, I have this set of real, genuine speakers. The only problem is that I have no clue what I'm doing when it comes to the fronts, which have built in powered subs. There's also two sets of speaker terminals on it, so, my short question is this: what do I do to make sure I'm getting the full use out of this thing? I'm sure it's not just a matter of hooking it up to the receiver and plugging it in, so any help you guys can give me is surely appreciated.

I managed to find this picture of this model online, and here's my main question: in the middle (to the left of the volume and crossover knobs), there's two jacks. It says processor above it, but there's one in and one out--I'm assuming that I can just hook a subwoofer cable from my receiver's pre-out into the "in" onto this speaker. If that's correct, then what is the "out" for?

It would be helpful if you gave us the make and model of the speakers. I would guess that the out is so you can daisy-chain them. Go from the sub out on the receiver to the first speaker in, the first speaker out to the second speaker in.