Hello Everybody. I'm a total amateur who enjoys picking up speakers when I see a good deal. I was given a pair of JBL Control 5 Studio Monitors 4 ohm. I wouldn't mess with these, but they look new. They virtually look like someone got them, blew them or whatever, then forgot about them. I've always wanted to have a pair of these, so I thought it worth my while to make an effort at repair. So there is sound coming out of both tweeters. No sound coming out of the woofers. They both also have not a mark on them. When I connected a 9 volt to the speaker wires, the woofers crackled. There is a fuse on the crossover circuit. I have not pulled the speaker apart yet. So two JBL Control 5, they look untouched. No sound out of the woofer. I would appreciate some education and advice.