Years ago I built 7 speaker cabinets with customized mid-woofers and what was the best soft dome tweeter on the market at the time. One detail in the design I was very proud of and which resulted in good improvement in the sound was my brilliant idea to make gaskets for all of the drivers from 1/4" thick Sorbothane - a very soft visco-elastic polymer. The material isolated the drivers from the cabinets and from each other and absorbed energy from the speaker frame. The result was a much improved transient response and more detail when reproducing very complex and dense passages in music. I thought I was a genius and bragged to anyone who would listen that I had discovered a brilliant solution to increasing the resolution of already state of the art transducers installed in acoustically ideal enclosures.
Well... that was then.
After approximately 7 years, while I was spending more than half my life in a tiny apartment in Virginia for my hob there, I noticed some deformation on the fronts of my amazing speakers. I chose to ignore it because I assumed it was nothing, or perhaps (I thought) it was flaws in the original finish I hadn't paid attention to before. I was also very busy and had relationship issues with my then wife, so dealing with some strange sights on my speakers seemed a low priority at that time.
Then I found myself alone at home after a separation and I started making the house my own. One part of that was restoring my HT to it's original glory and start watching movies and listening to music MUCH more often. That's when I realized what I was seeing was a black, sticky, goo oozing out of the speaker cut-outs and slowly flowing down the fronts of my speakers. It was gross, nasty, and almost impossible to get off my fingers if I made the terrible mistake of touching it. I assumed it was a sign the Sorbothane gaskets were failing, so I pulled out one of the woofers to see what I could do to remedy the problem.
Remedy the problem.
Remedy...
Oh crap... behind the driver I saw that every ounce of the gasket has dissolved entirely into that black tar-like goo. It had flowed into the rear of the woofer and coated the bottom of the back side of the frame, surround, and cone. Because it had solvent properties the rubber surround was no longer adhered to the frame and, well, the woofer was ruined. I tried various solvents to clean the goo, but only Alcohol seemed to help as it would thin the goo so I could wipe it off, little by little, with a paper towel. It was a mess, and I was devastated.
Once I realized what was going on, I started looking at the other speakers where I had used sorbothane gaskets, and that was every single one of my hand-built speakers in my 7 channel system. It became clear that ALL of them were in the same condition, though some has oozed more out of the front than others.
I cried. I got angry, I wracked my brain as to how this could happen. I couldn't understand any of it.
Sorbothane is supposed to be very reliable and is known to be temperature and chemically stable. Hmmm...
Well, I knew I couldn't fix these speakers, so I went through months of emotions resulting in a desire to make new speakers with new technologies, but without Sorbothane. This time I am using Silicone Rubber which is supposed to be even more chemically stable.
So, what caused the Sorbothane to turn into goo?
Well, it was noticed on this forum last week in a photo of a GTG and Pauly suggested that perhaps some airborne chemical, like a cleaner or aerosol, might have caused it to dissolve spontaneously. I mean, ALL of gaskets failed during the same period. I began digging through my memory of life in my home and had settled on the idea that perhaps the one time my A/C failed and some refrigerant leaked into the house was likely the culprit. While not proven, it seemed likely and I have lived with that theory as if it were true until today.
What happened today?
I am removing all the old gear and speakers from my HT to make room from installing my new speakers as a two channel system and when I took the main stereo speakers off the bass bins they were stack upon, I discovered I had used multiple layers of the same Sorbothane sheets, also cut by me and the same tools as the gaskets, in perfect condition. I had isolated the upper cabinets from the lower with layers of the very stuff which spontaneously melted into the very Bile of Satan.
What?
Even the portion of the Sorbothane under the speakers which came into contact with the oozing goo from the gaskets is in perfect condition. It just has the goo stuck to it, no damage.
What?
So, here I am struggling again with why my Sorbothane failed.
Well... that was then.
After approximately 7 years, while I was spending more than half my life in a tiny apartment in Virginia for my hob there, I noticed some deformation on the fronts of my amazing speakers. I chose to ignore it because I assumed it was nothing, or perhaps (I thought) it was flaws in the original finish I hadn't paid attention to before. I was also very busy and had relationship issues with my then wife, so dealing with some strange sights on my speakers seemed a low priority at that time.
Then I found myself alone at home after a separation and I started making the house my own. One part of that was restoring my HT to it's original glory and start watching movies and listening to music MUCH more often. That's when I realized what I was seeing was a black, sticky, goo oozing out of the speaker cut-outs and slowly flowing down the fronts of my speakers. It was gross, nasty, and almost impossible to get off my fingers if I made the terrible mistake of touching it. I assumed it was a sign the Sorbothane gaskets were failing, so I pulled out one of the woofers to see what I could do to remedy the problem.
Remedy the problem.
Remedy...
Oh crap... behind the driver I saw that every ounce of the gasket has dissolved entirely into that black tar-like goo. It had flowed into the rear of the woofer and coated the bottom of the back side of the frame, surround, and cone. Because it had solvent properties the rubber surround was no longer adhered to the frame and, well, the woofer was ruined. I tried various solvents to clean the goo, but only Alcohol seemed to help as it would thin the goo so I could wipe it off, little by little, with a paper towel. It was a mess, and I was devastated.
Once I realized what was going on, I started looking at the other speakers where I had used sorbothane gaskets, and that was every single one of my hand-built speakers in my 7 channel system. It became clear that ALL of them were in the same condition, though some has oozed more out of the front than others.
I cried. I got angry, I wracked my brain as to how this could happen. I couldn't understand any of it.
Sorbothane is supposed to be very reliable and is known to be temperature and chemically stable. Hmmm...
Well, I knew I couldn't fix these speakers, so I went through months of emotions resulting in a desire to make new speakers with new technologies, but without Sorbothane. This time I am using Silicone Rubber which is supposed to be even more chemically stable.
So, what caused the Sorbothane to turn into goo?
Well, it was noticed on this forum last week in a photo of a GTG and Pauly suggested that perhaps some airborne chemical, like a cleaner or aerosol, might have caused it to dissolve spontaneously. I mean, ALL of gaskets failed during the same period. I began digging through my memory of life in my home and had settled on the idea that perhaps the one time my A/C failed and some refrigerant leaked into the house was likely the culprit. While not proven, it seemed likely and I have lived with that theory as if it were true until today.
What happened today?
I am removing all the old gear and speakers from my HT to make room from installing my new speakers as a two channel system and when I took the main stereo speakers off the bass bins they were stack upon, I discovered I had used multiple layers of the same Sorbothane sheets, also cut by me and the same tools as the gaskets, in perfect condition. I had isolated the upper cabinets from the lower with layers of the very stuff which spontaneously melted into the very Bile of Satan.
What?
Even the portion of the Sorbothane under the speakers which came into contact with the oozing goo from the gaskets is in perfect condition. It just has the goo stuck to it, no damage.
What?
So, here I am struggling again with why my Sorbothane failed.
