I have 3 Audiobahn 12" subwoofers. Im looking to buy an amplifier but im not sure how large of an amp i need. Each woofer's RMS is 500w. Ive also seen wiring options where u can wire these three woofers to a single amp and it comes out to 1.34 ohm's but yet all of the woofers are 4 ohm. PLEASE HELP ME!!! i just need to know how much power i need to drive these woofers. THANKS