Bondo, an unusual product to use for dampening? It does become very hard after fully cured but I imagine a nice thick application would have positive results if from nothing else than it's pure mass.
I wrapped my old Klipsch LaScala's with something that I can no longer remember.
Quite often today when I see those TV commercials for that FlexSeal product I think about how it might just be the perfect substance to dampen something like the outside of an ole school horn. Comes in a very thick liquid form and could ultimately be applied about as thick as you wanted. Dries to a very pliable rubber like substance.
Thank goodness that's something we don't have to give much thought to with modern horn speakers.
In any case I'm not about to start tearing apart my JBL HDI-3600's, it might void my 5 year warranty. LOL
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