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soundboy
08-19-2007, 09:28 AM
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...

Thom
08-20-2007, 10:19 AM
Thanks for the tip. It's nice to know when someone has a good experience. So often people only report bad experiences. It's too bad there isn't some reference of surrounds one could refer to and purchase the one that they felt served their needs. Still, I have to believe that "the ones you get on ebay" takes in way too many to fit any one description. It's to bad a database hasn't been built. I wonder if there aren't santeprene surrounds out there close enough to fit some of the drivers I but have found no access to catalogue info on these things. Suppliers seem over vigilant to protect their dealers and re-coners don't see time spent going through this kind of stuff with a customer as particularly profitable. I don't begrudge the re-coner his profit but why should he be able to control all of the information.

Also, seems like pricing should be more like auto parts. A garage charges much more for the part than you can buy it for. He has to. If the part fails he's out more than just the part. If his labor isn't just right (nobody is dead on every time) he may have to eat the part. You get the idea. I doubt that re-coning is so easy that if we could all easily by parts we would all be doing our own speakers and if a garage has to bail you out of your own repair it stings, a re-coner could do the same. A garage won't install your parts that you bring in or if they do there is a whole set of ground rules. A re-coner could do the same. Just an idea. They could introduce a lot more openness and user friendliness and still remain at least as profitable. The first to go that way might even become more profitable. Any profit you make on parts that just go across your counter pay you more per hour than if you install them.

soundboy
08-20-2007, 11:07 AM
Just trying to help. I know the subject has been discussed ad nauseum on here before....but not the differences in surround pliability or thickness.
I sure found out how good the little 4301's really sounded in the bass! I had heard some nice origonals before, but when I got mine, they seemed a little more hard and forward than I remembered....not any more.

You are right about a blanket statement on the ebay surrounds...I am almost certain others may be getting the same surrounds as Rick Cobb....but how is one to know?

Besides, Rick's are very inexpensive, and none of the kits on ebay include the very helpful CD alignment disc...
who the hell would do it the old way, by removing and messing up the dust cap, when this tool works so well???

I have only refoamed a half dozen woofers....but they all came out factory perfect....
And, I might add, neater than a lot of the "factory authorized" jobs. Some of the dustcaps look like a caulking gun was used to apply the cement! :blink:

Years ago, a factory guy made me pay $10 extra, to put the foam on the back side of the cone on a 2245H...because it was more difficult!:bs:

No offense to the many many great refoamers/reconers out there. You are appreciated...

SEAWOLF97
08-20-2007, 11:29 AM
I have only refoamed a half dozen woofers....but they all came out factory perfect....Years ago, a factory guy made me pay $10 extra, to put the foam on the back side of the cone on a 2245H...because it was more difficult! who the hell would do it the old way, by removing and messing up the dust cap


I've had Infinity refoams where the gap is so tight that shimming was the only way , sometimes it has to be done "the old way"

you've been busy , Pete.....when I first met you, you were a "refoam virgin" :D

On the back harder ?? For me , on the front is harder.

( see my post about the Advents refoam where the outer edge of a reversed foam is glued on the underside of the step down adapter that Advent used for putting a 10in cone in a 12in basket)

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I've never seen a foam with a manufacturers mark or name and my local refoam shop (JaMac)
says they all come from Asia...anybody know any different ?

soundboy
08-20-2007, 11:37 AM
[quote=SEAWOLF97;182242]you've been busy , Pete.....when I first met you, you were a "refoam virgin" :D

It only takes overnight to remedy that situation a half dozen times:p



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Allanvh5150
08-20-2007, 12:46 PM
I have used some of Ricks product, and found the quality and ease of use to be very good. He also has other things like dustcaps and the like. I need to refoam some 117's and was dissapointed that he didnt have the kits for them in stock. I think I will wait until he has. Kudos to RC.:)

edgewound
08-20-2007, 03:21 PM
Also, seems like pricing should be more like auto parts. A garage charges much more for the part than you can buy it for. He has to. If the part fails he's out more than just the part. If his labor isn't just right (nobody is dead on every time) he may have to eat the part. You get the idea. I doubt that re-coning is so easy that if we could all easily by parts we would all be doing our own speakers and if a garage has to bail you out of your own repair it stings, a re-coner could do the same. A garage won't install your parts that you bring in or if they do there is a whole set of ground rules. A re-coner could do the same. Just an idea. They could introduce a lot more openness and user friendliness and still remain at least as profitable. The first to go that way might even become more profitable. Any profit you make on parts that just go across your counter pay you more per hour than if you install them.

Thom...
that would be in a perfect world.

I'd be glad to install a customer's supplied surround...and I have...but most of the time they were sent the wrong surround.

Also...lots of business have protected dealer networks, and there is a reason for it....it's to try to maintain a higher level of quality... and if a part is defective from the factory, the authorized servicer can send it back for a replacement. In addition, there are factory trained procedures that should be followed.

In regards to the aftermarket....there isn't much adherance to JBL's standards of performance. There isn't some industry oversight committee that guarantees your JBL to perform to factory standards of performance and cosmetics.

The system surely isn't perfect, but as has been discussed many times in this forum....OEM parts are the best.

Thom
08-20-2007, 05:38 PM
Thom...
that would be in a perfect world.

I'd be glad to install a customer's supplied surround...and I have...but most of the time they were sent the wrong surround.

Also...lots of business have protected dealer networks, and there is a reason for it....it's to try to maintain a higher level of quality... and if a part is defective from the factory, the authorized servicer can send it back for a replacement. In addition, there are factory trained procedures that should be followed.

In regards to the aftermarket....there isn't much adherance to JBL's standards of performance. There isn't some industry oversight committee that guarantees your JBL to perform to factory standards of performance and cosmetics.

The system surely isn't perfect, but as has been discussed many times in this forum....OEM parts are the best.

I was looking for a system that would protect the re coners profits. This is important. Without that he won't be there when you need him. And at the same time give the do it yourself type some choices and flexibility. The exact factory parts are best if what you want is what your driver was when it was new.