The Z-5500 draw power from the usual AC outlet. Power supply is built in with external heatsinks and so you have just a cord.
Due to the high power draw, if let say your heating/ AC unit in the basement goes on/ off randomly, you might hear a static interference from the speakers or sub makes a poof sound. I know mine does that since my room is directly above the unit.
THe 3 color cables is for the main, rear, and center sound inputs.