I have often thought about adding a sub woofer to my car, and sometime in the future still may. I am not one of those audiophiles that wants to compete, or one of those 16 year old kids I hear drive down my street (Thump.. Thump.. Thump!) when I am sitting in my house .. but I do like to have good sound in my car.

Right. A properly-tuned subwoofer will not make your car thump as it drives down the street.

When Doug Burnside heard my system, he commented on the fact that my car had more low bass than he's used to hearing in competition systems. Yet when I roll up the windows, you don't really hear the stereo much at all, and there is no unnatural thumping. The bass from this system is smooth, flat, and tight, not boomy.

My license plate rattles a little, though.

A good subwoofer, when used properly, is all about getting the overall spectrum balanced correctly for the listening environment. In my case, I like to hear the low bass notes even when I'm driving down the freeway. Hence my slightly boosted low frequencies.