I read with some interest the re-foaming sticky thread, and using the 30hz test tone as a voice coil centering method... Everything I've ever read before, and every (mostly retired) audio pro I've talked to insists you want to shim the voice coil to keep it centered and square. I can see as how running AC (30Hz) into the voice coil would center it on the 'in and out' Z axis, but I can't quite picture how that would keep it properly centered in the gap, radially. Can anyone explain this? I understand electromagnetics and such pretty well as an amateur scientist and general techno-geek.
FWIW, after doing tons of reading, I'm having a local pro sound shop re-foam my 2214H's (L100T) as I don't trust myself to get it right the first time... One of the cones is partially separated from the voice coil too (probably happened in transport), the shop's tech said no problem, he's fixed lots of JBLs like that.