I read through your white paper on waveguides and constant directivity. I didn't know the amount of research and thought that went into every detail of your designs. Incredible! Although most of it went over my head, I learned so much, and am going to read it through once more tonight.
Wayne, I recall reading a post by Zilch where he said something along the lines that 12" mid woofers are better matched with waveguides. Maybe this was a generality because he did say your 4Pi was a great design. Im curious on the differences between choosing a 12 or 15 as the midwoofer. He also tried to get the midwoofer and waveguide as close as possible on the vertical axis. What are your thoughts on this?