Originally Posted by -Shadow
I have an old Infinity TSS 1200 sub that died a few months ago (second time it died, Warranty the first time). I just got around to opening it up to see if I could figure out what went wrong. The obvious problem is it looks like someone took a blow torch to the back of the board. I know the electronics are toast but what can I do with the box and speakers? I don't want to just throw away a good speaker and box.
You need to first complete the survey of the damage. Most speaker systems are disassembled by first removing the speaker driver which you have apparently already done. Then clip the wires from the circuit card to the speaker at the circuit card end. Then check the woofer driver out by hooking it up in place of one of your main speakers. It should make a somewhat muffled and bass-shy sound if it is OK. You should also check the voice coil for rubbing.
This is a fair article with more details:http://www.fixitclub.com/Electronics/Speaker_printer.shtml
The business of gently but firmly pressing on the cone evenly and listening for rubbing is very important. A speaker will make sound but will still be defective if its voice coil is rubbing.
One of the economic stories that surprises many is the fact that the enclosure is a major part of the cost of most subwoofers. I was just looking at a pro-grade subwoofer that sells for $1500 or so. The manufacturer both specifies and sells the only electronic part which is the speaker driver, for about $500. In this case the course of action seems like a no-brainer.
Not every subwoofer situation makes things this obvious, but matching a new driver to the existing enclosure is very doable.
If the driver is OK, then replacing the amplifier is a possibility. it is also reasonable to replace the amplifier with a sheet of wood that tightly and non-resonantly covers the hole, and has just a set of speaker terminals on it. You can find a lot of the sort of parts you need including the amplifers at web sites such as Parts Express.