( If you can manage the extra space ), I'm especially partial to this Jensen implementation of the BLH ( back loaded horn ) using a 2220a, along with a horn driver . ( Click the pic, to read a really nice back-story to the displayed project ) .
BTW, Zilch passed away a few years back ( our dear, dear old friend was very instrumental to the success of Wilberforce's project ) .
Bigger is ( usually ) better in the land of horns ( & waveguides ) . And this Jensen bass horn is bigger than the JBL "scoop" being bandied about .
This projects HF horn is made by QSC , available from
PARTS EXPRESS ! ( ignore the use of the Selenium driver, use your JBL or even better, an Altec 802-8G ) .
( If my project ), I'd prefer to see if I could get an Altec 811b radial to fit the space ( instead of any waveguide ) .
Just a thought !