A new clone is in the making . This time a JBL SRX815. I'm using a date and audio 15-in woofer along with the exact waveguide with a JBL d220ti compression driver. I'll get some more updates as I go along. But so far, this thing is turning out really nice. You'll notice no bracing yet. I'll be adding bracing, but I really needed to see how everything would fit so that I didn't put any bracing in the way of either the ports the woofer or even to get to the compression driver.
Looks like it’s going to be somewhat of a beast!
Following your advice (on another post...), I decided to build these speakers concepts for my small band. In addition, I do want to get into this speaker's world and be able to build and tune them with my own hands.
Since I'm just getting started into this kind of world, I don't have the ability yet to measure this twitter through the horn you recommended. I wondered if you could be kind to share your twitter FRD and ZMA files? (I'm going to use the same exact driver you proposed on your links)