Subwoofer problem
 

Today while I was driving I noticed my subwoofer was not working. I have one 10" infinity sub. So I opened the trunk with the music on and noticed my sub amp was on, but the subwoofer cone was not moving. So I applied a little pressure on the subwoofer cone and it started working. However, when I removed the pressure it would stop working again (within a few seconds).

Is my subwoofer burned out? Do I need a new one? Any suggestions?

I still have to unscrew the woofer from the box and take a look at the connections.

You have broke one of two wires that goes from the connection terminal to the cone. You can solder it if you are experienced, but be careful because if you put too much soldering metal on it, it will become stiff and it will brake again when the cone moves up and down.

Infinity's have a lot of trouble with their voice coils loosening off the terminal... just solder it back on...

This morning, I noticed that the bass suddenly kicks in if I put the volume up to 21 or so. Then if I lower it to 18 or 17, it stays on. However, if I put the volume down to 0 again and then increase it below the 21 mark, the bass does not work.

However the above did not happen every single time. There were a few cases where I increased the volume passed 21 and the bass still did not kick in.

Could this be an amp problem instead?

Any ideas on how I can isolate the problem?

What type of amp are you running? How old is the amp and do you have the amp mounted to the sub box? If it's a cheap amp then this of course may be your problem, or if the amp is old one of the resistors could be going out. Then again if your a dumbazz and mounted the amp to the box, the vibration could have brole a solder on the circuit board and when the amp gets a little vibration, is able to make contact again and thus your hearing the bass.

It a mtx 225wrms class D mono amp.

Its not that old. Its mounted to the trunk floor (beside the sub box).

I think I fixed the problem!

I unscrewed the subwoofer from the box and connected it to the amp. I noticed that there were tiny sparks by the the soldered wire - positive terminal connection when I increased the volume. This suggested that there was a problem with the connection. I removed some of the black insulation around the soldered wires and re-taped it (making sure there was a better connection). Looks like it fixed the problem. I'll watch it the next few days!