Rustling sound when turning potmeter

[manis]

I'm hearing a slight rustling sound in my left speaker when turning the potmeter, between 6 and 7 o clock only. It has become noticeable after using the SEX 2.1 for 2 months now. The previous owner used it only a couple of months before me. The amp has been assembled at Bottlehead HQ, so I don't think it has anything to do with faulty construction.

Couple of questions:

-What is the problem?
-Will this get worse over time?
-Is this the result of the poor quality of the stock pot and less likely to happen if I put in a better one?
-Any suggestions as to replacement? brand/model etc.

[adamct]

1. Sounds like a problem with the volume pot.
2. Don't know.
3. Not sure i would stay the stock pot is of poor quality, but you may have gotten a defective one.
4. Use this: http://www.mouser.com/Search/ProductDetail.aspx?R=RK27112A0A16virtualkey68800000virtualkey688-RK27112A0A16

Best regards,
Adam

[Grainger49]

Often running the volume up and down will clean the oxidation from the carbon on the pot.  If this doesn't clean it, the next step is a spray cleaner like Deoxit. 

If that doesn't help, and it should, then you get into which pot, do I use a stepped attenuator and which?

[earwaxxer]

I'd upgrade the pot. It will sound better as well. As Granger was hinting at, the stepped pot is the best, but a log pot is more adjustable, but not the best sounding.

[Doc B.]

Just exercise the pot by twisting it 20 or 30 times.

[jimiclow]

Spend $15 and get the Alps.

[adamct]

If you decide to go for a stepped attenuator, then I would recommend the ladder-style ones from Vintage Audio Lab on eBay. Run a search for: "Valab 23 Step Ladder Type Attenuator Potentiometer 100K Log Stereo". Be sure not to limit your search to the U.S. only. I couldn't find any until I PM'd them. Turns out they had some listed in Australian dollars that weren't turning up in my search.

Best regards,
Adam

[manis]

Thanks for all the tips, guys. It's amazing what a little trick like Doc prescribed does. I twisted my SEX knob (duh) 20-30 times and oh what a joy. The rustling sound is now almost inaudible. You really have to do your best to hear it.

[Grainger49]

Try the spray for a better cleaning.