Hoping you people would offer me some help and advice. Looking to add a subwoofer to my small, club-oriented PA. Currently, we are using a Carvin powered mixer with a small club-oriented PA system. I have this mixer (rated at 1600W, 400 W to each main, 400W to each amp for the monitors), and it has an XLR output with an internal crossover for a subwoofer. Pretty basic, common portable PA system, nothing fancy. The mains I am using are Carvin 15" 3-ways, and I am running the drum mics and vocal mics through it. I have been wanting to add a subwoofer to the system, and I was hoping some of you could offer suggestions on powered subs for this system. I have been looking at Carvin powered subs, but are there other brands that are decent quality and don't carry a hefty price tag? I will likely go with a single 18" sub based on the recommendations I have gotten, but I'm hoping some suggestions on brand would be helpful. I've looked at Peavey, Seismic Audio, Mackie, etc... and the prices are all over the place. Any help here? Thanks in advance.