Support | Rockford Fosgate Woofer Wiring Wizard. Determine what amplifier to use with your subwoofer system. Select your Woofer Quantity and Woofer Impedance to see available wiring configurations. The results will display the correct subwoofer wiring diagram and impedance load to help find a compatible amplifier. Amazon: rockford fosgate wiring: Electronics Rockford Fosgate R500X1D Amplifier + Wiring Kit Bundle R500X1D 500W RMS Prime Series Class D Monoblock Amplifier + BAK42 Complete CCA 4 Gauge Amplifier Wiring Kit with 2-Channel RCA Interconnects. 3.7 out of 5 stars 6. Electronics $157 $ 157. 00. FREE Shipping.