Ok, I am very new to this, never done this before. I bought the Dual XD7500 55 x 4 channels 220w, and 4x6 pioneer 100w speakers to replace the stock speakers in the front of my 1979 Buick Le Sabre. I've hooked everything up the stereo turns on, when I hook the wires to the speakers no sound comes out. Sound did come out of the stock stereo and wires, but not out of the stereo I bought, I used the right wires and no sound. Is this because I have no amp yet or am I missing a step?