Look at pro-audio crossovers. For Behringer they are DCX and DBX products I believe. The DCX2496 is very popular for people running multiple subs and MBMs because it is very inexpensive.

You might try posting on a forum like diyaudio.com to see what people recommend. For some reason, folks there think the DCX is ok for subs, but not as an active crossover on regular speakers.

Fred

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Blujays1: Spending Fred's money one bottle at a time, no two... Oh crap!