As the title implies I'd like to improve the sound of the base stereo in my '13 GT, I will be trading this car in on a '15 stang in late fall or early spring next year so I don't want to put a ton of money into a new system. I don't need navigation or a lot of bells and whistles and I don't want to add weight to the car with a sub (and I listen to metal not rap so big bass isn't a concern). So can I get better sound by just upgrading the speakers? If so which ones fit and work well with the factory head unit? A new head unit the better option? I'm not that knowledgeable about new stereo stuff I just want to crank the As I Lay Dying without cringing because it sounds so wimpy now. Thanks guys!