I got my son a used 2011 Honda Civic. It has a Pioneer FH 8000BT (I think) installed. In the trunk is some heavy wiring from what appears to have been an amp of some type. The rear speakers mounted on the deck behind the rear seats are Pioneer TS A1674R. I do not know what kind are in the door. On the rear deck between the left and right speaker openings is another opening about 7" in diameter. Basically I want to upgrade the speaker system (at a reasonable price). What I would like to do is replace the two Pioneer speakers (my son says there is a rattling noise coming from them) and maybe a small subwoofer to go into the opening between the rear speakers along with an amp to power the subwoofer. Can you give me any suggestions on what type of equipment I should be looking at. Please keep in mind when I fooled around with car stereos, Gerald Ford was president and a Craig Powerplay 8 track and two Jensen speakers was considered "state of the art". Thanks for any help.