I know almost nothing about home stereo systems, but do enjoy watching movies and listening to music. I have a pair of Yamaha NS-777 tower speakers hooked up to a simple Yamaha RX-596 stereo receiver. I like the sound, but I would like just a little bit more bass. I have an old 5.1 surround sound system in my closet (I'm in college so moving between apartments and such I just am to lazy to set it back up right now). The sub I bought for the 5.1 system is maybe 3 years (I don't remember) old. It's a JBL Powerbass PB12 subwoofer. Nothing fancy just a circuit city subwoofer. I hooked it up to the receiver, and then hooked the speakers off the sub. When I turned it on it made a loud pop (which brought back my memory that I think part of the reason its in the closet it that its broken). If I turn the music all the way up and you put your ear up to it you can just barley hear it playing faintly. I unhooked the 777's and then turned it up and again its just barley playing faintly. I took the sub(cone/what-ever-you-call-it) out and looked and the fuse is not blown and the circuit board inside has nothing broken on it. All the wires are attached inside and none are melted (as far as I can see) or broken. My guess is that it's the (do you call it cone?) big round speaker part that you unscrew from the bottom of the sub and unhook a red and black wire from - has a big magnet on it (sorry about the lack of education). Can I just replace that part? It it worth it, or should I buy a new sub. I don't really feel like spending 3-400$ again. I figure though that it might cost half that now because it's 3 or 4 years old, so I'm sure they make better ones now. Again I'm just looking for the cheapest way to get a 12in sub to complement my ns-777's for listening to music off my computer or radio. Thanks for your help! P.S. If / When I get a new sub, how do I know how loud I can listen to it without blowing it again? Or is it not the volume but some incorrect settings that blow subs. I like to turn it up (the point of subwoofer/speakers), but I don't know when to stop, or what is safe. Thanks again!