[albee1952]

I'd need to know exact models of speakers, processor and amps to offer the best advice. Traditionally, a 3-way crossover feeds 3 separate sections (woofers, mids, horns) but it sounds like your top boxes(with the 15 and horn) are passive, so you should see if the processor offers a 2-way mode so you can feed the subwoofers properly(like from 90Hz, down) and the top boxes(from 90Hz, all the way up to 20KHz).