[Guido S]

Seriously, the sound from my stock setup is awesome save one little problem. The underseat speakers are dead underpowered. All I want is to bring up the base in the least expensive way possible. I don't want the JL600/6 or the Bimmertech DSP. What I need your help with is choosing an amp that will power the bass only as the mid and tweets are OK with me.
Help me with what I'm trying to do not what you'd like me to do. Sure throw out caveats but help me find an Amazon.com amp and wiring kit that would do the job.

[RunFlatOut]

I've been doing a bit of reading on the matter these days and to be fair, going through the existing posts and stickies, the basic message is that the HiFi setup is pretty damn decent and the amp should be the first target in the upgrade path.

I'll be following your progress with a keen eye because I'd quite like to freshen my setup a bit too. I was so impressed initially, and I've been pretty damn happy with the tunes for the majority of my trips, but 100k km down the road and I'm a bit sick of my sound. I can't quite put my finger on it though so it's hard to decide on an upgrade path. The volume is there, the body is there. Crap sources sound worse, good sources can sound great, which is healthy behavior and the sign of a solid piece of kit. But it all feels a little too thick maybe? Like it doesn't quite breathe enough air, or that it hits the walls too quickly. I dunno, I'm not an aurologist obviously. I've been wondering if simply adding crossovers would help the system breathe easier and play to its strengths, but I've never done that.

Until I make my mind up I'll be focusing on other fun bits, adding USB, stuff for the passengers, etc. But yeah I'll be curious to see what you go for. Good luck!

[AtlasM]

If you only want to upgrade the subs, have you looked at the Bavsound upgraded subs?

http://www.bavsound.com/BMW-Undersea...ofer-Upgrades/