Reaching Beyond My Capability

One of my greatest passions in life has been doing small electronics repairs as a hobby. Never in a billion lifetimes did I think I would become the repair person in the family. My brother has asked me to look at a few things, and it's usually a simple repair. Things are slowly progressing in difficulty though, and that's forcing me to learn a little bit more to reach that next level. On the repair list is a Peavey Bandit that my brother picked up super cheap. It turns on, it just doesn't producing any sound. I opened it up and did a board inspection, which didn't yield any results in showing what was wrong with the amp. All of the components looked fine, nothing was scorched or broken. Fuses were ok too.

At the end of the signal was the 12" speaker. I popped off the leads and checked the speaker to see what impendence it was and the multimeter read -- nothing. He's dead, Jim. So I haphazardly  hooked up a small speaker just to see if this amp produced sound, which it did. I reported back to my brother all he needed was a replacement speaker and it's good to go. Well, that's been a few weeks and it's taking up quite a bit of space, so I decided to take it upon myself to see what I could do to move this project along a bit.

The first thing I learned was the Scorpion speakers have removable magnets. Interesting! Once the magnet is removed the voice coil is right there. Let's check some continuity. From the lugs to what should be the start of each side of the coil is fine. Then I found continuity throughout the entirety of the coil. After probing around with my multimeter I found the break in the coil is RIGHT BESIDE where it should connect to the output lug. Solder bridge to the rescue! Except, it's not that easy. Dealing with the speaker was tough, and trying to solder in such a small space was even worse. After some trial and error, mostly error, I finally got a solid 6.2 ohms through the speaker consistently.

I carefully replaced the magnet, snugged it up, placed the speaker back into the Peavey and it worked. For a brief period of time. I checked the speaker and the continuity was yet again broken. I painstakingly ran another solder bridge and got the continuity back and tried one more time. Again, the speaker worked and after about ten minutes decided it was done. I'm not trying it again. If it's done, I'm done dealing with it. I'm not a speaker repair person, I'm just someone who can search on Google and then apply that knowledge to real life. The real MVP here is the ability to remove the magnet that gave me the chance to find the fault and attempt the repair. I've made sure the solder bridge isn't massive and rubbing up against anything, but it shouldn't be so frail it falls apart. I just think this speaker is done and doesn't want to be repaired, so I will abide by its clear wishes. At least I tried.