if you want to play loud, distortion free music, then change the sub. Sony is worst of the worst when it comes to car audio. But, if you still want to keep the sub, then I'm guessing that's an SVC sub so you will need an amp 300-350wrms @ 4ohms. Briding a 2 channel would be better for this. Not sure tho if the sony would handle that power, but I'll go search for some amps in a few minutes