Originally Posted by
edgewound
Gap depths have to be the same for diaphragm interchangeability. The gaps are deeper in the 2482 & 2485 that came with phenolic diaphragms. My 1976 JBL Professional catalog with 2440 & 2482 says 20,500 gauss for all the large format drivers, my 1980 catalog says 18,000 gauss for both 2441 & 2482....both catalogs state 118dB sensitivity for these same drivers. I can't explain the difference in gauss....you're theory sounds good.
I haven't measured them,though...for the diaphragms to be truly, usefully interchangeable, the top plate gap depths must be the same for the voice coils to be symmetrical from either end of the gap...or they'd be terribly distorted.
Thanks,
Edgewound