Then you'll love Audio HQ...

Seriously, a bigger box might help, or, I sell a processor called the Maxbass that will help you get more bottom end. Its not a bass boost, or an epicenter. Its actually a car version of a very popular studio processor. How it works is much too much typing, but it is very sophisticated, and very good.

If you can get to your amp easily, I could put one in your jeep, and demo it for you, in about 5 minutes.

Toby