I modelled the Delta 10 in WinISD for the only failure I've gotten with that program. Driver specs must be off or something because the modelled curve and the RTA missed by over an octave in both sealed and ported configs. I wanted to use them 2-way in the Pi Suudio 2 boxes but no amount of tuning would produce acceptable bass. So I use them where they work best. If I had more room I'd try Wayne's midrange horns, and might anyway.

John