I have done some checking. Untill just a couple of years ago the Honda used a Alpine built head unit. It has a plug on the back that a special din (like?) cable can be atached that provides a preamp level out and it is BALLANCED. This might be the ticket to the sound you crave.
I also agree with Swampwalker about the position of the drivers
I also agree with Swampwalker about the position of the drivers