I recently added the aftermarket Kicker 10" sub. It definitely fills in nicely where the Bose system drops off or distorts. However, I believe simply replacing the front 6x9 and rear door speakers with a better quality speaker will "clean" it up. I am not looking to make my ears bleed but simply cleaning up the mud. Have any of you replaced just the speakers? I am not adding an amp etc. But if you have replaced the speakers, please let me know. Would appreciate the input.....