The problem with biamping is the speakers. In the PA and Hi-fi world there is very little overlap in the bandwidth of the drivers being used, each is well attuned to the range it operates in, and bi-, tri- or even quad-amping works well. In the electric bass speaker realm the bandwidths of the drivers have such a wide overlap that when you bi-amp you literally lose half their potential output. For instance, the average 15 works well from 50 Hz to 1kHz, the average ten from 100 Hz to 2 kHz. If you crossover at 500 Hz a full octave of the 15's range and better than two octaves of the 10's range isn't utilized. If you're going to biamp and have it work well then your speakers have to be properly configured to do so, combining not 15's and 10's, but 18's and 8's.