In lieu of finding an H92 for my center channel, I'm thinking outside of the box.
I have a 1217 and an H91. The 1217 flares to 5-1/4". The exit on the H91 is ~4". Hmmmm, that portion of the 1217 beyond 4" diameter could be grafted onto an H91 for a longer horn that should be capable of reaching lower frequencies.
Can anyone measure the distance between the 5-1/4" end of the 1217 (at the flare inside the perf plates) and that point at which it necks down to 4" and report this depth? (If this distance is too short, it wouldn't be worth the excercize or messing up a good 1217.) I don't think the H87 is the same as my 1217 is 1" longer than my H87s were. (It's same length as an H91)
Can the change in curvature at this point and resultant dispersion/interaction be modeled somehow?
Thanks