JBL K130 original cone small wrinkles in cone

[Blair Hines]

I just received a JBJ K 130 speaker and I was checking the foam and seeing if there was any rub. I must of pressed to hard on the cone during my inspection and now there are smal looks like wrinles in the cone. I would post a picture but I spent the last hour trying to fiqure out how to post a picture of the speaker. My question is how bad does wrinkles
have to be and still not effect the porformance of the speaker. Blair

[David Higginbotham]

Play it and you'll have your answer. If it sounds fine...no problem. If it's an issue...you'll likely hear it. Manually pushing on a cone to move it can cause a problem as it may be forcing it asymmetrically. Hearing what sounds to be rubbing while moving the cone doesn't necessarily indicate a problem. Depending upon the cause...those wrinkles may disappear when you play through it.
Dave

[Dave Grafe]

Re-size your photos to a max dimension under 2k pixels and they will upload. The forum has an image file size limit to keep the servers from crashing now that cell phoe cameras default to 4k and more.

As for wrinkles in the cone that is generally evidence that the speaker has suffered an overexcursion, i.e. the voice coil at some point traveled clear of the gap and temporarily collapsed the cone structure, usually from feedback or other over-loud signal. If you pushed on the cone too energetically that could do it too. Play it until it falls apart but plan for a future recone.

[Blair Hines]

Just added a picture

[Dave Grafe]

Yep, that crease is a fold line. There has been trauma in its past, you would have to use some force to do that with your hands. If the voice coil isn't rubbing it's fine to use it but plan for a recone, forum member Jeffrey Maxwell does excellent work.

[Bill A. Moore]

Quite a few years ago, I bought a pair of D130's, with one "needing a recone", there were two creases more pronounced than yours, and it did have coil rub. I left the "bad" one in an unheated storeroom for several years before finding it again. The creases were almost gone, and no rub when moving the cone! I sold it as needing a recone, but the fellow that bought it actually played it for a while!
I wonder if the temperature differences caused the cone to move and straighten itself?

[Blair Hines]

Thanks Dave for the information on this speaker. I have one of Jeff's K-130 that he did for me and it sounds excellent!!! I wanted to see if I could hear that much of a difference in a
speaker with the original cone and one that has been reconed. Thanks everyone for your help with this.
Sorry for the sloppy posts trying to add a picture.

[Blair Hines]

Thanks Dave for the information on this speaker. I have one of Jeff's K-130 that he did for me and it sounds excellent!!! I wanted to see if I could hear that much of a difference in a
speaker with the original cone and one that has been reconed. Thanks everyone for your help with this.
Sorry for the sloppy posts trying to add a picture.

download/file.php?mode=view&id=21933

[David Higginbotham]

I've had a couple of JBL's over the years with similar defects that were already installed in amps I'd purchased. I may even still have an E-130 that was in a Nashville 400 if I look through my boxes but neither had any issues and sounded like a JBL should. I've had a few where moving the cone gently made a rubbing noise and I expected the worst... that the voice coil was shot. But, none of them had issues in sound or performance and it was only original cone JBL's I've experienced this with. The age of the cones add to their magic and I've read that if a speaker stays in the same position for many years the voice coil has the potential to become slightly oval shaped. I've read it's a good idea to rotate the position of speakers over the years to help eliminate that risk. I have no evidence this was true but it sure sounds plausible.

Bill mentions something to consider as temps and humidity affect most everything. So long as the crease isn't actually a tear through the cone and when you're playing you're not getting any distortion or audible issues...I suspect it'll be fine. I'd limit the power rating to 100 watts and try to avoid any detrimental inputs like plugging in a jack while it's powered and keeping the volume to zero when turning the power switch on/off. Those sudden spikes can quickly ruin a voice coil.

I've used several re-cones and still have two JBL 130A's that GW Walker used for his stereo steel amps. I had two K130's from Woody Woodell. They all sounded like JBL's. But to say they were as nice as the original cones would be a bit of a stretch. Jeff's re-cones may have captured what others have lacked. His reputation is certainly stellar and he would be a great source.

Good luck and happy playing!
Dave