#140620  by TeeJay
Is anyone using gaskets on the rear of the JBL's on a front load HT style cabs with clamps? Most seem way too thick. One of my E120s had an OEM rubber o ring that seemed to not work very well either. I would think the metal speaker flange should sit snug against a nice flat baffle board? Any insight would be appreciated-
 #140622  by Smolder
Mounting any JBL typically requires longer bolts. I've mounted a few front mounts, never with a gasket. Never had a problem. YMMV.
 #140624  by tatittle
I bought some cheap foam rear gaskets (likely ebay) that stick to the baffle as opposed to the rear of the frame edge that are very thin. Seem to work fine though they wont last with lots of speaker changes I imagine. My understanding is they are primarily to prevent warping the frame of the speaker (and then voicecoil rub), but I suppose they could help seal an enclosure for tighter specs/performance. Im not sure I can hear any difference with or without the gasket...but I don't use that cabinet much anymore (its really more of a bass cab with glued baffle closed back). No clamps on that cab though, reg bolts.
 #140626  by hippieguy1954
I've had success with both the OEM "O" ring as well as styrofoam gaskets that peel and stick onto the speaker flange. The main reason for any gasket there is to eliminate/reduce any vibration. I think it's a good idea, but probably not absolutely necessary.
 #140673  by williamsaut
A rear gasket on a front loaded speaker could be for sealing an enclosure that's a closed cab or ported specifically to drive the resonant frequency down as in hifi speaker cabs. I'd use as thin a piece of foam or tape as possible to limit rattles. If the baffle is dead flat as it should be, rattles should not be a problem. Tightening the speaker rim down on a piece of foam could warp the rim and shorten the life of the speaker. This should really be watched when rear loading a speaker as there's a lot of compliance in the cork rim gasket. Bent rim = out of round coil and eventual rubbing and a blown speaker IMO.