Bottlehead Forum

Bottlehead Kits => S.E.X. Kit => Topic started by: manis on May 20, 2013, 07:35:00 PM

Title: Rustling sound when turning potmeter
Post by: manis on May 20, 2013, 07:35:00 PM

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.

Title: Re: Rustling sound when turning potmeter
Post by: adamct on May 20, 2013, 07:39:44 PM

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 (http://www.mouser.com/Search/ProductDetail.aspx?R=RK27112A0A16virtualkey68800000virtualkey688-RK27112A0A16)

Best regards,
Adam

Title: Re: Rustling sound when turning potmeter
Post by: Grainger49 on May 20, 2013, 11:53:40 PM

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?

Title: Re: Rustling sound when turning potmeter
Post by: earwaxxer on May 21, 2013, 04:11:26 AM

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.

Title: Re: Rustling sound when turning potmeter
Post by: Doc B. on May 21, 2013, 04:41:55 AM

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

Title: Re: Rustling sound when turning potmeter
Post by: jimiclow on May 21, 2013, 05:00:08 AM

Spend $15 and get the Alps.

Title: Re: Rustling sound when turning potmeter
Post by: adamct on May 21, 2013, 12:38:05 PM

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

Title: Re: Rustling sound when turning potmeter
Post by: manis on May 21, 2013, 07:17:30 PM

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.

Title: Re: Rustling sound when turning potmeter
Post by: Grainger49 on May 21, 2013, 11:49:40 PM

Try the spray for a better cleaning.