I utilized a pair of B&C 21SW152 woofers in this project. B&C builds beautiful sounding drivers and this 21 inch woofer is no exception. They handle 2000 watts RMS (we're giving them 2400 watts intermittently) which is a necessity with this particular customer. He's a brute and not afraid to push my gear to the limits! One can't help but love people like this--I love fearless characteristics in an individual.
I purchased a set of $10.00 drawings from decware.com and made a few modifications to Steve's design in order to accomodate a massive, single driver. You can locate the prints in his master catalog. The prints don't come with a cut-off sheet, so I posted one on my free "jensen imperial horn" page. I also post the cut-off angles--the original prints don't have them.