...are angled back at a 60-degree angle. (One prototype had one wing hinged, but that wasn't nearly as stiff--nonresonant--as it should have been.) The outside wing is 30" deep at its bottom, tapering to 21" deep at its top, while the inside wings are 25" to 23" deep. The wings are stiffened considerably don't resonate NEARLY as much as they used to. Here's one in-process pic.
![Photobucket - Video and Image Hosting](http://i89.photobucket.com/albums/k220/jeffreybehr/OB%20JG6518%20speakers/IP5_rear2_800h.jpg)
There now are more chunks of MDF screwed to the backs of the wings, and probably I'll replace even the double-layer 2-1/2"-deep left-right braces with 4"-deep MDF braces.I'll post another pic of the current rears later today.