Does anyone know if the head unit powers the six speakers and a separate amp power the sub or is there a factory amp separate the head unit that powers all the speakers? If it just powers the sub, do you think it could push an 8" in a ported box?
The factory radio is made by clarion and powers the front and rears only. The factory sub has it's own tiny amp. It can only be used with the factory speaker because it is rated at 1ohm. Any higher speaker eg. 4ohm, the amp will produce almost zero volume.
Figure: cd player-40x4 (more or less)
tiny factory amp-20x1
97 nissan 240 se, stock (for now) except for custom sounds.
01 nissan sentra se/pp, stock (my girl's car).