I have a pair of E-715 Cerwin Vegas with the 15 inch speakers. I am replacing all three speakers. Do I make the replacements all 8 ohms? I bought the 500 watt replacement woofers @ 8 ohms. I bought 8 ohms 80 watt horn type tweeter. I still need a 5 inch mid, should I keep everything at 8 ohms, or will it even matter?..thank you.