Bottlehead Forum

Bottlehead Kits => Crack => Topic started by: MikeSattler on October 03, 2017, 11:44:54 AM

Title: Buzz at louder volumes
Post by: MikeSattler on October 03, 2017, 11:44:54 AM

Hey guys, looking for some assistance troubleshooting a minor issue here.

So you know that buzzing noise that you get from your crack when you crank the volume and you don't have anything plugged into the RCA jacks? Well my Crack has started to exhibit that same buzz (albeit not as loud as when nothing in plugged in) when I have RCA cables or shorting jacks plugged in.

It wouldn't be a huge deal but it is much louder and starts to get noticeable around 11'oclock on the pot when I'm using my 5998 (I'm assuming it's more noticeable since the 5998 has higher gain)

My Crack was dead silent for years so this is a new weird issue, any tips on where to start troubleshooting?

Title: Re: Buzz at louder volumes
Post by: Paul Birkeland on October 03, 2017, 01:04:35 PM

Is this noise occurring at a reasonable listening level if music is played into the Crack from your source?

Title: Re: Buzz at louder volumes
Post by: MikeSattler on October 03, 2017, 06:30:45 PM

It can be noticeable at times while music is playing that needs a lot of gain (like classical)

Title: Re: Buzz at louder volumes
Post by: fullheadofnothing on October 04, 2017, 06:37:16 AM

Since the noise level is changed by the volume control, the noise has to be entering at the volume control or before it. Can you post pictures of your build?

Title: Re: Buzz at louder volumes
Post by: MikeSattler on October 05, 2017, 05:49:41 AM

Hi Josh, thanks for taking a look at this, I appreciate it!

Here's a few angles of the RCA jacks and volume pot. The RCA jacks are insulated with white teflon (I think?) washers on both side of the chassis. The volume pot is and Audio Note 100K pot which has a plastic housing so I think it's fairly well insulated.

Title: Re: Buzz at louder volumes
Post by: fullheadofnothing on October 05, 2017, 06:54:22 AM

Could you please post your pictures to the forum? When making a post, there is a section below the text box that says "Attachments and other options".

Speaking personally, I do not click on download links from strangers.

Title: Re: Buzz at louder volumes
Post by: MikeSattler on October 05, 2017, 09:04:07 AM

Sorry didn't see that button, I updated the post

Title: Re: Buzz at louder volumes
Post by: Paul Birkeland on October 05, 2017, 10:00:11 AM

I would try using the stock pot.  Plastic is not generally as good of a shield as most metals.

Title: Re: Buzz at louder volumes
Post by: MikeSattler on November 14, 2017, 11:04:04 AM

Thanks for the help, ordered a stepped attenuator and that fixed the issues I was having.

Interestingly, even though the pot housing is plastic on that attenuator it was introducing noise when touching the chassis  :o