Alright, I bought myself an LCD controller board off of eBay for an old unused laptop screen. It works, but it needs a special 4 pin connector for the speaker output because the headphone jack doesn't always work. I found an old 5.1 system of which I only need the 2 stereo speakers and the subwoofer (making it a 2.1 system). It works great, has an audio quality good enough for my usage but one volume knob out of 4 of them was somehow torn off (pics included, kinda hard to explain). That knob controls the loudness of the subwoofer so I do need it. I only need the control for the 2 front speakers and that subwoofer, so I would like to know if there is any way to get rid of the other 2 controls and repairing the sub one while keeping the stereo speakers? I'm a construction engineer student with very little electronics knowledge (the most I've done was resoldering some wires and modding my Guitar Hero guitars), so any tip really helps.

Pictures: https://imgur.com/a/ZleVE1T

 

Alright, I bought myself an LCD controller board off of eBay for an old unused laptop screen. It works, but it needs a special 4 pin connector for the speaker output because the headphone jack doesn't always work. I found an old 5.1 system of which I only need the 2 stereo speakers and the subwoofer (making it a 2.1 system). It works great, has an audio quality good enough for my usage but one volume knob out of 4 of them was somehow torn off (pics included, kinda hard to explain). That knob controls the loudness of the subwoofer so I do need it. I only need the control for the 2 front speakers and that subwoofer, so I would like to know if there is any way to get rid of the other 2 controls and repairing the sub one while keeping the stereo speakers? I'm a construction engineer student with very little electronics knowledge (the most I've done was resoldering some wires and modding my Guitar Hero guitars), so any tip really helps.

Pictures: https://imgur.com/a/ZleVE1T

Without a circuit diagram it is a little difficult to give you a simple answer, but here is something you can try:
Carefully unsolder one of the control potentiometers that you don't need from the circuit board then test the operation of the circuit to see if that has affected the operation of the two speakers. If everything still works, replace the damaged pot with the one that you removed. It has the same resistance value so it should get the woofer going again.

 

You only need to remove the remains of the woofer-pot there.
One of the two others may rerplace it, if desired.

Take care not to use too hot solderpen/gun when removing the potmeters.
Anyhow, You may just remove the wooferpot, and use one of the other for Your sub-leve-lcontrol.

 

I agree you could probably "borrow" one of the other pots to replace/repair the broken one, but I'd strongly recommend doing a proper fix and get a new one. It won't cost much more, will be less work, will maintain the original functionality if you want to sell or donate the kit, and presents zero risk of doing damage by removing an existing pot.

 

Without a circuit diagram it is a little difficult to give you a simple answer, but here is something you can try:
Carefully unsolder one of the control potentiometers that you don't need from the circuit board then test the operation of the circuit to see if that has affected the operation of the two speakers. If everything still works, replace the damaged pot with the one that you removed. It has the same resistance value so it should get the woofer going again.

You only need to remove the remains of the woofer-pot there.
One of the two others may rerplace it, if desired.

Take care not to use too hot solderpen/gun when removing the potmeters.
Anyhow, You may just remove the wooferpot, and use one of the other for Your sub-leve-lcontrol.

I will try to do that as soon as I get my hands on some desoldering braid.

I agree you could probably "borrow" one of the other pots to replace/repair the broken one, but I'd strongly recommend doing a proper fix and get a new one. It won't cost much more, will be less work, will maintain the original functionality if you want to sell or donate the kit, and presents zero risk of doing damage by removing an existing pot.

I don't really have much to lose here, the sound system I took the electronics out from wasn't used for a good 5 years at the very least. I live in Croatia, meaning that people don't really ship to here (for some reason), I have no plans of giving away/selling the kit and to be honest if I do damage something it's not a big deal since it's already damaged.