I'm not really sure. I'm going to grab my dmm and see what the coils read. I did the 9volt test and got no responds but there's no scratching when pressing on the cone either. Maybe the tinsels are broken or something stupid, I just got it in my hands and it wasn't my sub. I'll try to figure out what's up.whats blown. and what size. i might be interested in making a frankinstien between my tc1000 and your tc 9