JBL Sub keeps blowing fuses.

[WillVT]

I have a JBL Sub150 that I have been using in my main system for a few years. The other day, I noticed that it was not outputting anything. I pulled the fuse, and sure enough, it was blown. I ordered some replacements, just to rule out a faulty or old fuse. Well, it blows it a second after power up.

Has anyone ever fixed this problem on a sub like this? I have nothing invested in it, as it was a curb score. I know it's nothing special, but I have been pretty happy with it's performance. I will try taking it apart when I get some time and see if anything is obviously wrong.

I would love any advice.

 

[swechsler]

What's your experience with electronics diagnostics and repair? Blowing a fuse repeatedly can be caused by a faulty output transistor, but I wouldn't just jump in blindly and start replacing things at random. Many subwoofers use integrated output devices rather than discrete transistors, and these are a bit more difficult to test, especially when you can't get power to them. Translation: there's no one obvious cause. A simpler repair might be to purchase a replacement plate amp from Parts Express, assuming they have one that will fit the opening of the original.