I'm new to the DIY forum here, I've been watching for a while and the thought of new main speakers and a center channel is intruiging. The Polk Audio RT35i's and CS245i are getting a little long in the tooth. They are great speakers for the money but after hearing several other brands I want something different. I discovered one of the teachers at school is into DIY and is willing to help especially with the crossover design but I want some input on the drivers and tweeters I have picked out. I've been looking through Parts Express and found what I beleive to be a nice setup. Looking at some Morel DMS-30 tweeters, Davis Acoustics 100CKW8DF 4" midrange, and a Vifa MG22WO09-08 8 1/2" woofer. I'm thinking about a crossover at 400Hz and 2.2kHz respectively. As for the cabinent, I would probably build the first prototype out of 3/4" MDF with a trapezoidal profile from front, top, and sides. The center channel would emply the same tweeter and midrange but with a 5 1/5" or 6 1/2" woofer. Woodworking will not be a problem, I'm no stranger to woodworking or trigonometry for the complex angles on the trapezoidal cabinent. I'd appreciate any comments or suggestions on my design.