Re: 60 Degree DIY Mid Hi - They need a name ?
Ivan, thanks for the good pieces of continuing education.
Peter, thanks for the further info on the design trade offs. I'm seeing why your boxes have ended up where they are.
I am definitely in the process of building another round of 60 deg DIYs, and at this point am inclined to copy yours, corner lopping included, if I decide I can't go with mostly 12mm for weight reduction.
Also been thinking about this idea for trying to measure box resonances, to be able to just try things and see how fill or bracing might work with a lighter cab........http://www.mh-audio.nl/tips\ach-01.htm
Have to build new 60 degrees because I shredded one of the 12" RCFs,...... and it looks like the cone hit one of the BMS HF terminals.
I knew I was playing it close, but still am a little surprised it hit. Maybe I forgot to high pass, dunno.....been trying so many things I get confused 
At any rate, this pushes me over the edge for building another round, if only to gain some more XT1464 clearance.
I'll use the existing boxes as 90 degrees only.
Don, great to hear your gig went well. I bet the DIYs are perfect for an outdoor HT setup with their clarity, other than the wider dispersion you needed.
As Peter said, the difference in pattern between the 60 degree and the 90 degree is waaay more than the numbers would indicate. I guess because how abruptly the 60 degree rolls off outside its pattern.
I too am amazed by their throw for their size.
Probably the real reason I shredded a cone is that I just had to push one for grins a few times this weekend.
I put one 60 deg on top of 3 labhorns, which was almost a good match but the labhorns were on a deck and not fully half space loaded. Needed one more lab i think...but three would probably be good if they were fully on the ground.
Didn't meter anything but I'm guessing it had to be at least 105 db C slow at a measured 150 feet....which implies 138 at one meter.
And sooo very clean !! Till it broke haha.....glad I only run one at a time !
edit... I should add that the boxes I built have alot less clearance between the coax and the 12" drivers because of the way I did the 12" baffles and spacers; not because the posted plans lack clearance.
I used a 12mm spacer on top of a non-routed 18mm baffle board.
I don't want others to have any clearance concerns here.....
