Wayne, thanks for designing a pro-sub that those of us who can't necessarily get the marketed stuff can build and use. There were a lot of times when I was gigging in the "bar band" that our homebuilt subs just took a header because of design flaws and thermal breakdown. A couple of the 12 Pi's with a couple of 1000W amps sounds like it would work very well! When you're up and ready to put out the design, whether kit or assembled, I'll be sure and let all the struggling musicians I know find out about them.