Bottlehead Forum

Bottlehead Kits => Crack => Topic started by: EraserXIV on August 01, 2013, 11:13:05 AM

Title: White noise 12AU7 socket
Post by: EraserXIV on August 01, 2013, 11:13:05 AM

I have this recurrent issue where I hear white noise through the Crack and I need to jiggle around the 12AU7 socket a bit for it to go away. The white noise does not fluctuate with the volume knob. Anyone know what might be causing this? I know it's not the tube since it happens irregardless of the tube I use and those tubes are quiet in other amps. I'm thinking it's a cold solder joint but wanted to hear any other thoughts before I try to resolder everything on that socket.

Title: Re: White noise 12AU7 socket
Post by: Doc B. on August 01, 2013, 11:25:47 AM

Hmm. Typically the sources of white or pink noise are tubes, semiconductors or resistors. As a starter you might try measuring across the 22.1K ohm resistors and see if they are true to their value.

Title: Re: White noise 12AU7 socket
Post by: EraserXIV on August 01, 2013, 12:45:37 PM

Thanks for the quick response! I got impatient and resoldered all joints on the 12AU7 socket before I checked if there was a response to my post  ;D

Well, problem solved for now! It's dead silent again. Found a couple suspect joints that could have been the source of the problem.

Title: Re: White noise 12AU7 socket
Post by: adamct on August 01, 2013, 01:03:54 PM

Glad you got it fixed so quickly. Enjoy!