If your deck has Center Bass Freq, High Pass and Low Pass settings for rear channels, then I would just clip the Rear sub wires at the amp and run them straight to your deck, bypassing the amp and headaches of wiring RCA's completely. The stock amp puts out 22W, my aftermarket HU puts out the same, and with the adjustments mentioned you would have enough control to make it sound good. Ask me how I know

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