I wouldn't worry about it if I were you emedwhat. The reason is that you are basically doing an active bi-amp since you are using bookshelf speakers and using a subwoofer to do the bass notes. The only difference is that the woofer is not in each one of the speaker cabinets, but rather, it is in its own enclosure which is optimal for the driver's Thielle-Small Parameters. It'd be a bit pointless to bi-amp bookshelf speakers because you would only be separating mid frequencies from high frequencies. Neither of them require that much power in the first place, assuming of course that you have the crossover and subwoofer enabled in your receiver.
