A while back, I posted for recommendations about a decent bass amp for a beginner. IICR, Max was the one that recommended checking out the Fender Rumble series. The Rumbles are truly killer for the price (I got mine used for 150 bucks) and are loud enough to jam along with friends. However, as I've gotten better, I'd like an amp that can be a bit more versatile and generate some more aggressive tones when needed. Is there a good resource to learn about all the different types of bass amplification (e.g. DI & PA's vs combos, etc.)? I purposely tried to avoid learning too much about the gear side of playing bass early on so that I'd just focus on playing and not become a gearhead...again. I could just lurk TalkBass and read the forums here but I'd love a resource that digs into the pro/cons of different setups without the uh...strong opinions that forum conversations can generate.