I recently bought a Pioneer GM D9601 Amplifier and a Pioneer TS-W261S4 subwoofer. Im wiring them to a 2014 Mini Cooper and as I'm using the stock head unit I have cut into the the rear speaker wires and ran a speaker wire to an adaptor allowing me to plug them into the RCA input on my amp. The amp accepts speaker wire input so no need for a low output connector. I connected everything however my subwoofer only makes a small vibration when I play music (about the same amount as my regular speakers do) does anybody have any suggestions on how I can resolve this thanks.
If you have the level of the rears set lower than the front then that will affect the overall balance. Maybe wire the amp to the front output not the rear. Adjusting the input level of the amp may help.
You may have the crossover frequency in the amp set too low.
That will limit the range of sound that the sub gets. Your music may not have VERY deep bass even if it has a lot of upper bass.
That amp also has a bass boost on the remote. Try that last.
The cabinet can affect the output too.