<font color='#000000'>I have a Yamaha RX-Z1 receiver and a Yamaha MX-1 amp to drive my main speakers that are rated at 4 ohms. Should I set the impedance selector to 4 or 8 ohms? My speakers are Jamo D870 main, D8 center, and D8 surrounds. I currently have the switch set at 8 ohms will this...