I investigated the lack of the lower spectrum of sound more and noticed that the 5 inch drivers that are supposed to provide most of the base are in the floor under the seat and are pretty much are muffled by all of the soundproofing in the floor of the car. The lack of volume from those speakers makes me wonder whether they are even positioned upward in the car...
TRY THIS: Put your head near the floor in front of the front seats and you will barely hear the floor speakers at all. Even when I turn bass all the way up in the tone settings, I have to have my head within inches of the floor practically under the front seats in order to hear the bass at a volume that is balanced with what is being put out from the other speakers in the car.
What's up with that? If you turn up the bass on the stereo to hear the lower spectrum, you will simply get much louder muddled output from the smaller speakers in the car well before the output from the floor speakers become noticeable.