If you know what you are doing than why are you asking for help?tytyguy said:why would it sound like poop? i do know what im doing.
Yes it is stupid to run 2 different subs size in the trunk. The 12s are quicker than the 15 so you will have a tigher bass on the 12s and some lagging bass with the 15.
What kind of car do you have where you can fit two 12s and a 15?