Scratchy pots, Eden WT-405

[beardedclam]

I have a problem with mt Eden WT-405 (manufacter date June 2006). The master volume potentiometer is very scratchy. I tried spraying the pots with an electrical spray designed for scratchy pots, it worked a bit and was better for a little while but it seems to be just as bad now. I bought this amp used so I can't really say if it has been exposed to dust.

I have another issue with the master volume pot; it is loose, when I tried to tighten it I noticed that the threads are stripped (is this normal, I have never seen this before). Also the bass pot has no indentations (no notchy feeling when rotated), it looks to be original.

Any advice? Thanks

[RickenBoogie]

Maybe it's time to go see an amp tech?

[beardedclam]

I was hoping to avoid that cost and do it myself

[beans-on-toast]

Not all cleaners are created equal. DeOxit (100% liquid or spray) is the industry standard because of how well it works.

If cleaning and lubricating doesn't work, you might have a leaky capacitor in the signal path in the circuit that the pot is in.
The leaky cap places a DC voltage in the circuit. The scratchy pot is a telltale sign. You would need to check or replace the capacitors.

[beardedclam]

Thanks Beans, this is very good information. I will start by purchasing DeOxit (is spray better than liquid?). Is it better to stand the amp on end (knobs on bottom) when I spray? I very much hope that the capacitors are ok. Thanks

[beans-on-toast]

It helps if you can place a small vacuum attachment close to the opening of the pot and attempt to suck out any dust and dirt that is inside the pot.

This is the one that I use DeOxit S-CD100L-25C. I find that the spray can get into places that you don't want it to go, the liquid can be more economical. The stuff is expensive. If you can, position the amp so that the liquid will penetrate into the pots most efficiently. Let the liquid flow from top down. You apply the product, then move the knob back and forth throughout the entire travel of the pot. Follow the direction for the product.

Also use the Deoxit on the inout and output jacks. Anywhere there are contacts. On a tube amp, this includes the tube sockets and tube pins. You can also use it on your bass.

[beardedclam]

Thanks Beans, very much appreciated.

[DiabolusInMusic]

+1 for DeOxit, it resolves most scratchy pots. It seems to almost leave a residue when it dries which is probably why it works better. On the other note I've heard from guys who've used Deoxit for 20 years that said film turns and seems to cause issues.... which are once again fixed by Deoxit.

[vin*tone]

What spray are you using? Some contact cleaners do not lubricate.

[beardedclam]

I used "Nexxtech" contact and head cleaner, I purchased it at The Source (aka Radio Shack) here in Canada.

Somebody once told me that PL-100 anti-friction spray works well (I have a can at home but I am not so sure that I want to experiment).

I was planning to purchase DeOxit Fader Lube, 100% F100L-L25C, 25ml liquid. Is the F100 better than the D100?

Thanks

[nikolozj]

Gasoline may clean the rust inside. I used once or twice. It'll take a time tho, before it gets off.

[beans-on-toast]

D series

F series

The fader product is not for metal contacts. I believe that the D is better for your application. Some contact cleaner products can gum up the pot and cause more harm than good.

[beardedclam]

Ok, thanks, I will get some liquid "D", thanks.

[vin*tone]

Originally Posted by beardedclam

I used "Nexxtech" contact and head cleaner, I purchased it at The Source (aka Radio Shack) here in Canada. ...

Cleaner. You need clean AND lube.

[beardedclam]

Lube? - like what?

[beans-on-toast]

The contact/head cleaner is simply a solvent. When you strip the gunk out of the pot with it, you should add some sort of lubricant to protect and lubricate the parts inside. DeOxit does this all in one step.

Pots are made in different ways. Many have a carbon coating on a substrate. Some of these cleaners are so strong that they can remove the carbon, effectively destroying the pot. This is why you need to be careful what you use.

Here is a look at the inside of a pot.

[beardedclam]

Thank again for all this great info, I really do appreciate it.