Weird speaker impedance behavior

[J M Fahey]

I cut open the confirmed dead one, and this is the amount of goo we are faced with.

Just give it 5 minutes, if repaired keep it as a "shop speaker" or spare.
Notice right rivet is covered and surrounded by goo, left one is not and is the first suspect.
That goo is soft and easy to melt with 30 seconds of heat gun each, and you remove it with tweezers or a toothpick.
Maybe you have exact same problem as PDF 64 and can solve it the same way in 5 minutes.

It will take less than going to the dumpster to junk it

[Randall]

I don't know what the goo is made of on this speaker, but it doesn't get very soft at all when hit with a heat gun. I'm sure it would pull the wire out with it.

In another experiment, I found that when hooked up to an amp, I could get it to abruptly cut completely out by pressing just right on the spider. So in the dumpster it goes.

[pdf64]

To access the wire / terminal through a blob of epoxy like that, I’d use a dremel with a grinding bit. Would need to use tape etc to ensure no resulting dust debris found its way into the voicecoil gap.
I guess that the ‘spider flex’ observation may indicate that the problem may not be at the tinsel terminal, perhaps close to the coil former / spider joint.

[g1]

Won't a solder iron melt epoxy (or whatever other kind of goo)?