I invite other bass players to post their ideas and experiences with modular rigs. Here are mine. In the last 5 years I have cycled through a large amount of gear in search for a modular rig that would achieve the tone I looking for. I ended up with the following: A Markbass F500 An Ampeg SVT-CL Two Ampeg VR 210 Two 1x15 custom cabs with Beyma 15G40 drivers What I like about this equipment is it modular capabilities. - For low volume I can use the F500 and one Ampeg 210. - For more volume and portability I can use the two Ampeg 210 and the Markbass. It's a bit heavy but I can carry everything in one trip, including my bass. - I can also use the two Ampeg cabs with the SVT. That's not one trip however! The SVT head is a two person carry for any distance. - The 210 + 115 combo works well for more volume. - The two 115 cabs driven by the Ampeg will deliver the perfect tone for blues and gobs of volume too. - For the real loud gig, I can either drive the four cabs with the SVT head at two ohms or use both amps and drive the four cabs. In this case, I would drive the two 210 with the Markbass (the Ampeg 210 don't take as much power as the Beyma 115) and the two 115 with the Ampeg. This configuration also allow me to run some distortion on one side and some clean tone on the other one. With this equipment, I have light and heavy, 10's and 15's, tube and SS, loud and moderate.