Not all foam surrounds are created equal...
Just a heads up to anyone on here considering buying surrounds....
USE RICK COBB...
Why?
I have a mint pair of 4301B's, that had new surrounds installed right before I purchased them. They did a good job, cosmetically, but one of the drivers had coil rub at higher input levels...
So, I got a kit from Rick Cobb, on this site, and replaced the surround on the woofer, lining up the coil with the 30hz tone CD..
That's when it was apparent that the new surround was MUCH softer and more pliable, and and when pushing on the woofers, the new one was much less stiff...
It sounded completely different...MUCH more articulate, much deeper bass, and just all around smoother and more musical.
I don't have the measuring tools, but no doubt the fs and damping are affected.
So, all surround kits aren't created equal, and the ones from Rick sound great.
Of course I replaced the other woofer surround, as well, and the same exact sonic differences were noted.
The old surrounds were not old and stiff, they were about a year old....and I have had many JBL woofers over the years....the factory foam on both my 2245's is still pliable and softer, like Rick's, even after years of use.
So, KUDOS to Rick, and a tip to use only his supplied surrounds...
I have a notion that the ones on Ebay are thicker, stiffer, and may fit, but take away the inherent musical qualities of the these great woofers...