It has two stereo cables that go to the sub where all the speakers plug in. One plugs into the front output, the other plugs into the rear output of the SBLive. So it is true 4-channel.
But I would like to convince you NOT to get it. Get a Cambridge FPS100 at the least, preferably a FPS2000. The ACS54 is weak, the sub is pretty much trash, and the satelites have not trebble. With volumes at 50% on the computer, and the speaker set to a comfortable volume, when you hit walls in Pod Racer it bottoms out the satellites, and they make a popping noise.
They just don't cut it, pretty weak too.