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Strange case of Sorbothane turning into Black Tar

Could something been sprayed on it, either accidentally or on purpose? I know nothing of your divorce, other than you went through one, maybe the ex tried to really get you were it hurts, your speakers. I would hope that's not the case, but I've heard of people doing worse things.
 
Call the manufacturer and then follow up with sending them pictures of the damaged speakers.

You never know...............

Do you have receipts from when you bought the material?

Yup, what him and Jeff said.
 
Did you have a cleaning service...ever? Could be they sprayed Windex or Pledge or some other cleaning agent on it...

That was my original premise, but if that were the case why didn't the exposed sorbothane under the speakers fail. Surely the exposed stuff got much more chemicals on it.
 
Here's a photo of one of the speakers where the goo is clear:
Sorbothane_Failure_01.jpg

During the GTG we removed one of the woofers and looked behind it, it was nasty!
 
No, I bought this stuff in 2007 and don't have the receipts for it. I have receipts for the speakers as well as my custom order form, but the accessories like the Sorbothane, acoustistuff, screws, and such I didn't bother to keep records for.
 
That was my original premise, but if that were the case why didn't the exposed sorbothane under the speakers fail. Surely the exposed stuff got much more chemicals on it.
I have my Mackie HR824s and my cleaning lady sprayed it with Pledge and wiped the whole cabinet and speakers with a cloth.
After the first time I saw that, I asked her to stop.
That could easily get it all over the drivers but not on the mats under the cabinets.
 
I have my Mackie HR824s and my cleaning lady sprayed it with Pledge and wiped the whole cabinet and speakers with a cloth.
After the first time I saw that, I asked her to stop.
That could easily get it all over the drivers but not on the mats under the cabinets.

My speakers don't have normal cabinets.

NewSpeakers_Finished_Cab_C.jpg

NewSpeakers_Mar_2008t.jpg

As you can see, the bass cabinets have a flat top, but the separate mid/tweeter section has a wide baffle and small rear cabinets. To dust one must dust all around the Sorbothane which is not only isolating the top section from the bottom, but is positioning the top so it is in-line and vertical. You can sorta make out the two layers of 1/4" Sorbothane between the top baffle and the bass cabinet.
 
And here's the rings I cut before I installed them:
Skaaning_Surround_32_Gasket_J.jpg

I followed the recommended process for cutting. Ideally I would have cut the rings with a water jet cutter, but I didn't have one of those.

The leftover discs are what made the rear support for the upper cabinets. I cut them in half to make half circles and stacked them up until the total height was ideal to make the upper baffle align with the bass bin baffle.
 
The surround speakers also failed, and they were mounted so the woofers were nearly 8 feet from the ground. It would have been difficult to dust with chemicals.

Skaaning_Surround_40_Installed_H.jpg
 
Sorbothane is designed and marketed specifically for vibration absorption applications. It is the most effective commercial material for vibration control. I chose it for that specific reason. I would be shocked to learn that vibration would cause this material to fail.
Notice that I suggested vibration as a cause - not the cause. Perhaps in conjunction with some other cause that was not anticipated by sorbothane's developers.

And, again as I mused, since you've eliminated "chemicals" as a possibility (I agree that I don't see how every driver "ring" was affected but not the pads between cabinets) then what's left? I suggested magnetic and electrical fields / currents. (The rings are in close proximity to the driver magnets, while the pads are further away. With the field strength being inversely proportional to the distance squared, it could be that they've simply escaped the effect (which could be cumulative, or threshold-based).) You've said there were no temperature excursions (like from a whole-house bedbug purge), so again, what's left?

So I'm going with a combination of vibration and field effect until someone comes up with a better theory.

Jeff

ps. That are likely many enthusiasts who have used sorbothane to decouple speakers from surfaces, and in my searching I've seen none report anything like what happened to you. Given that most of them likely are exposed to the same household chemicals that yours were, that further reduces the chance of that being the cause. But I've not yet seen anyone else use sorbothane as a ring to isolate / decouple the driver from its cabinet. So it must be in that application that you will find the solution. So again, what in that specific application could have affected it?
 
This from an amazon review:
“Used this to isolate the hum from a downstairs ceiling fan that can be heard from upstairs. At first it was great and the sound almost completely disappeared. However after a couple of months it had returned. When I took down the fan to investigate the material had disintegrated and turned into goo. Any point force applied to this stuff is eventually going to cut right through it. Force needs to be spread over a large area.”

Did you screw the through the gaskets when installing the drivers or were those cut out ahead of time? Could that have possibly weakened the material? I’d love to know what the manufacturer says.
 
I figured that I would look for some stories also:

Years ago, I bought an acrylic mat (made by SOTA) for my original SOTA turntable. It came with a thin sub-mat made of sorbothane that went between the acrylic mat and the metal platter. After about 10 - 15 years, I found one day that the sorbothane had melted or dissolved and some of it actually dripped down the sides of the platter into the base cavity. It cleaned up well with Goo-Gone, but it was a mess.

Yesterday I visited a friend who was experimenting with his old AQ sorbothane mat and I noticed that it was sticky and soft, so I told him my story and he pulled the mat of his turntable. It took an effort because it was really stuck, and it stayed in a ball when he finally pulled it off.

I have old sorbothane pucks that haven't turned gooey, so it may be a matter of formulation, but I thought I'd pass this along so you can give any sorbothane you might be using a regular check.
 
Here's a photo of one of the speakers where the goo is clear:
View attachment 8265

During the GTG we removed one of the woofers and looked behind it, it was nasty!

I'm sure it was very disappointing and disheartening when this goo issue started to happen. When you were out of state for that one job, was the HVAC system in your house turned off? Maybe extended periods of hot temperatures caused the sorbothane to melt?

Either way, it's good that this topic (sorbothane) is being discussed on the forum, maybe it will help other people out there avoid repeating the mistake of using this product.
 
Well... this thread was mostly my way of telling the story of how my pride and joy speakers failed, how great the emotional hurt is, and my process for moving past this terrible experience. No matter what I could do at this point, I cannot repair or recover my old speakers. They are gone. There is no going back.

So, as I already wrote, this is spilt milk. I have cried, thrown a fit, and proceeded through the stages of recovery, and am now moving forward. It was the completion of the new speakers which allowed me to speak openly about it.
 
Possibly the sorbothane had a batch miss mixture and the company has not published the problem. I have had a problem with the belt on a RtR do the same thing. goo. This I felt was time related because it was my Fathers machine from 1968

You could ask for a test with an AC provider by exposing some to the Freon to see the effect. Using a fish tank to create a chamber and over exposing with a sealed tank to the Freon.
 
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