I finally was bored enough to finish up (mostly) my Crossover Utility.The zip file does not include the VB runtime Dll's so if it doesn't work on your pc, just email me and I'll send you the file you need.
I've included a sample project that is the Theater 4 Pi's
This utility allows you to choose drivers, select crossovers and other passive filters, then export the whole thing to a Spice file for Simulation. All you have to do is open it in AimSpice and run the AC simulation and it should show you a graph of the freq response and a graph of the phase response.
Danny
Email for questions, sorry about all the popups, my free hosting deal sucks...