Bottlehead Forum

Bottlehead Kits => Crack-a-two-a => Topic started by: Happy Ghost on May 10, 2022, 11:39:56 AM

Title: Slight hiss with 6SN7 at -9DB setting
Post by: Happy Ghost on May 10, 2022, 11:39:56 AM
Hi All,

I have a fully functional C2A with the 2quiet upgrade, which I have been enjoying a lot for the past few months. Recently I got a few 6SN7's also for some tube rolling. But one of the new production tube gives a noticeable hiss at only the -9db setting on the coarse attenuator. At other volume levels above and below it is dead quiet. Any idea on what could be the reason? Should i let the tube just "cook in" for some time and hope that maybe that will fix the problem? or does it look like it could be a damaged tube?  Any ideas?

Rgds,
Title: Re: Slight hiss with 6SN7 at -9DB setting
Post by: Paul Birkeland on May 11, 2022, 04:59:59 AM
I would let it run in for a while.