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Wednesday, August 1, 2012

How To Clean or Replace The (potentiometer or "pot") Controls On Your Guitar Amplifier

How To Clean The Controls On Your Amplifier

Is that crackling and popping when you turn the controls on your amp driving you crazy?  Here's how to clean them and get back to the music.

There are spray "contact cleaners" available for this purpose, but in most cases just mixes the dirt and grime already inside with more dirt and assembly grease and may make the control operate worse than it is already.

Step 1Remove mounting knobs and nuts

The first step is to remove the knobs and nuts mounting the controls to the front panel to the amplifier.  Remember to keep all the parts sorted so you can find them later.

Step 2Unsolder the controls

After the circuit board is removed from the amplifier box, each control is removed and cleaned one part at a time.  Do not take them all off at the same time, because you may mix them up.

Step 3Remove old solder

Remove old solder and inspect the pads for any burnt or broken traces. 

Step 4Open the control

Open the control (potentiometer or "pot") by lifting the mounting tabs slightly.  Remember that these tabs will not handle being bent more than a few times before they break off.  If a tab breaks off, you may be able to solder it back on later.

Step 5Inspect dirty contacts

The control is made up of two main parts.  The contacts and the carbon resistor.  Each side must be cleaned without damaging them further.  If the carbon looks burnt or has broken areas, the entire control may need to be replaced.  If the contacts are worn too much or broken, the entire control may need to be replaced.

Step 6Cleaning

Carefully, clean the contacts and carbon with a pencil eraser.  Do not push too hard, and clean the eraser on a piece of paper when it gets too dirty.  Do not use any cleaner or solvent except rubbing alcohol or cleaner designated for this type of control.  Make sure to blow off any eraser particles left on the control before assembling the part.

Step 7Cleaning continued


I have a Peavey 50 Watt Amp. It's an older model and has that "Peavey Buzz". It's been in the Garage for Several Years now. I do think that I remember, that it did make a little Static Noise, sometimes, when turning the Knobs. It's great to see the Pics and how to Disassemble the Pots. Without having to experiment on mine. I actually have a couple of brand new Pots too. That I got from my Buddy. When he gave me the Amp. His Dad was an old Jazz Musician and my Buddy, didn't want the Amp. So, I got to inherit the Amp and some other Cool Stuff too. I got a 4-Track Reel To Real and a Stereo Recording Setup. With a Custom Made Desk and an Audio Gear Rack (that I let Slip Away later). That Dad, made him self. I also, got a Dynaco 400 Watt Studio Amp (which needed some repairs, that I did, but don't have a meter to set it properly, so I can't use the amp). A Pre-Amp (which I use ever day for my Home Audio Setup) and an Analog AM - FM Tuner (it's in my Rack, just for fun). Oh, and an RCA Patch Bay, that Dad Made too. I use if to combine all of my Home Audio and Computer Outputs into one Input, going into the Pre-Amp and then out to 2 Different Amps. A 100 Wat, Harman Kardon hk395i. Connected to, two 12 inch Speakers, with Horns and two 4 inch Speakers with Horns, for Mid Range, mostly. Also, I have a 5.1 PC Speaker System hooked up to the Pre-Amp too.

Dynaco Amp...

My Audio Rack (that I got when working as a Telco Installer) and my Home Audio Gear...

I use to run sound for Bands and developed a love for Mackie Mixers. I wish I had one for my Home Setup Now. The Patch Bay, does cause some signal loss, with several different sources turned on at the same time. So, I can only turn of 2 or 3 different sources at a time. That only bothers me, if I am running 4 Computers and want sound from all of them. I don't do that very often though. But, can't afford a real Mixer, right now. Still, I can get some pretty good sound, with what I have. I usually just use the PC Speaker System. Since the Big Speakers, Carry the Sound too far (right through the walls too) and bother the others in the house. It's all getting pretty old now. And my Harman Kardon Amp has allot of noise in it's Pots and so Does the Dynaco Pre-Amp. I have Sprayed it with some very good Electrical Contact Cleaner, called PBS. That is available here in Texas. I have used this stuff since 1976. But, without taking the Units Apart. I really can't get the Spray into the Contacts them selves. I learned about PBS, when I was a Maintenance Mechanic for Wichita Oil Co, back then. I did maintenance on their Gas Stations, Car Wash and Convenience Stores. They (we) were Converting old Service Stations into Self Service Gas Station - Convenience Stores. I worked on different kinds of Electronics. From Contact Switches in the Car Wash, to the then Brand New Technology of Electronic Read Outs. That we added to the old Mechanical Read outs on their old Gas Pumps. The were also installing new Gas Pumps, with Electronic Read Outs too. I've taken apart, several different types of Switches and Contacts. Cleaned them and made them work for a while longer. Before having to Remove and Replace them. But, Electrical Parts that can be Repaired are not that Common, these Days. Anyway... Back, to the Peavey Pots. I'm glad I found this Post on these types of Potentiometers or Pots. I think I remember trying to clean some Pots, on something that I had. Back when I was a kid. A Transistor Radio and or an old 40's - 50's Radio that I had. Without much success. And WD-40 will definitely Gum Up your Electronics, if you use it on Potentiometers or Pots and Parts like this. Now I know that they can be Cleaned. And I didn't know that using a Pencil Eraser would work, either. But, I do think. That, unless I could take my Pots apart, while still mounted on the Circuit Board and Clean them that way. And if I went to the trouble to Un-Solder the Pots. That I would just Save some time and Replace them. They don't cost allot and I already have a couple anyway. If only I knew then... What I can find Online Now!;) And if I could see as well Now. As I could, back then. And my hands were as steady, as they were, when I was a kid!:O


How To Clean The Controls On Your Peavey Guitar Amplifier (Potentiometers or Pots)
How To Clean The Controls On Your Amplifier
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