Sorry for the late post. Rwd, I don't believe you can use a floating ground(bridged) amplifier design with the RS-1B's active crossover and woofer towers. I think the servo will feed back. You'll know it if you've ever experience it-the sound is akin to Shamu, the killer whale, in heat. The Aragon 4004 is a good sounding bass amp for the money(but you have to get the amp off its soft rubber feet-try Black Diamond Racing mkIVs or even Tip Toes). A killer amp would be a Krell KSA-250. The Infinity RS-1B was such a great speaker(I'm trying to get a set for myself), really a reference speaker much like the Quad ESL-57 was a reference, but they beg for the best electronics(and set-up) you can do.