I went from a Hyundai Excel hatchback to a Ford Explorer and now my bass is lacking because of the much larger space to fill.I know its not my amp because its very strong (JBL GTO601.1).But my sub is only a Pioneer TS-W34C 12" in a 1 cu/ft sealed box.Now my question is do I get a better sub or bigger box or both,If so what would you recommend for my Explorer?