I have 4 ceiling speakers in my house that were pre-wired by the builder. I purchased a Harmon Kardon AVR 254 receiver and I was wondering how I am supposed to connect the four pairs to the binding posts on the back of the receiver. The speakers have 4 conductors connected. W1 is the green (+) and the Black (-), while the W2 is the red(+) and White (-). I appreciate any help anyone can give.