Need to replace Subwoofer volume control


I have an old M & K subwoofer a friend of mine is going to buy. It's a really good sounding sub. The rotary switch that controls the volume is really touchy and static-y when touched or adjusted. I thought it something we could replace ourselves.

Is there anything specific to a volume switch in a sub? Will most any switch work? I plan to remove the plate, remove the switch and get any numbers off of it.

Is there anything I should look at as a potential problem?
128x128frederick21
The specs that you are going to be concerned with are the resistance ( probably in the Kohm or 100Kohm range - 10 thousand to hundred thousand ohm range) since these are US made? this will probably be marked on the back of the potentiometer it's self.Is it a stereo pot or mono? If stereo - it might be either a linear taper ( most likely) or a audio taper.For your application - this might not make much difference.
If you can get at it relatively easily and there is a obvious opening in the case into the innards of the pot- consider spraying one of the CAIG lab products into it and rolling the pot from max to min several times as you do this.This may take care of the problem for several years - however -if it's going to take half a day to get at the thing - consider just replacing the pot entirely.
Stonedeaf...NOT Linear taper. It should be Audio taper, but these are so hard to find that Log taper is usually substituted. Characteristic of the original pot could be determined using an ohmeter once you get the thing out of the circuit.
>Stonedeaf...NOT Linear taper. It should be Audio taper, but these are so hard to find that Log taper is usually substituted. Characteristic of the original pot could be determined using an ohmeter once you get the thing out of the circuit.

Sometimes a shunted linear pot is used to approximate a log pot.

Cheap "log" pots are actually multiple linear segments and if used in a ganged stereo application you're likely to have problems where the segments line up between pots. So the shunted approximation makes more sense in that case.
Drew_eckhardt...Any time two pots are ganged there can be a tracking error. Why would a log pot be made as a series of linear segments? Seems to me that this would be more difficult to make than a straightforward log taper.
>Drew_eckhardt...Any time two pots are ganged there can be a tracking error. Why would a log pot be made as a series of linear segments?

For a pot to have log taper resistance per unit of rotation needs to increase. With wire-wound pots the windings need to increase in circumference as they go. I'd guess that conductive plastic pots have to decrease in cross-section. Those sorts of manufacturing processes are more expensive than mating two or three linear segments which approximate a log taper.
Find a REAL electronics supply store in your area, and purchase some residue free contact cleaner spray, like CaiKleen 41 by Caig. Shoot some up the shaft, and work the control back and forth for a while. Sometimes just working the pot back and forth enough will clean the contacts without any sprays. If that doesn't help and you decide to replace it- Once you've determined the value needed, contact Michael Percy: (http://www.percyaudio.com/Catalog.pdf) He stocks Noble, ALPS, TKD and even bare stepped attenuators, so you can build your own if you care to. If the one in the sub is mono: you can use a stereo pot, and just wire to one section. It never hurts to upgrade an existing pot w/a Noble, ALPS or resistor ladder. If it happens to be a 50kOhm pot: I've got a brand new, stereo, stepped Noble attenuator that I can send you for free(well- you pay postage).