Bass Unit for 06 330i

Although I have to Logic 7 sound system, the quality of the bass isn't that great. I want a little (okay, a lot) more thunder when I'm playing Rod Stewart's "Hot Legs", etc. I noticed BavSound is working on a plug-in unit but what is available out there now that can give me more oomph to the music? Any recommendations, approx cost, etc. Thanks. Jim.

Have you played around with the equalization?

Bass is not really the answer to getting a good quality listening experience. You need to tune the sound to be as natural sounding as possible via the eq setting and the Logic 7 system is very accurate in its reproduction.