In the chasing of this notion I've fallen over a guy who specializes in this sort of beast - sells wooden phase plugs for various FR drivers, has damped the basket and magnet structure, etc. He favors the BD design which uses 2 per cab, one firing upward and back @ 45degrees. Interesting stuff on his site about various obscure tweeters as well. I may run these FR and augment with the TAD 1602, depending on how the things sound alone.

I'm sure they do have higher WAF than Karlsons, or my TAD beasts! LOL.

Look forward to experimenting!