THose are beautiful Mike. What drivers are those???
I apologize for taking so long to answer your question, don't know how I missed it.
The tweeter is a BG Neo3 PDR planer magnetic (currently unavailable due to sale of BG to Christie Digital).
The midrange drivers are GR-Research LGK's. While actually a full range driver, in this application the LGK's roll off at 200Hz so they perform as midrange drivers. Because of this, a sub unit that can play up to 200Hz is necessary.
Danny Ritchie has recently designed a wedge shaped OB bass unit using three GR-Research/Rythmik 8" servo drivers and an HX300 amp per side.
http://www.audiocircle.com/index.php?topic=135399.0 Alternately, you could use two 12" servo drivers and an A370PEQ amp per side for more low end output.
I am currently in the process of building a pair of the wedge bass units with three 8" drivers per side to go with a pair of Wedgies I'm building for someone else.
Mike