Acceptable tube Microphonics?

[Joe Garfield]

Re: 6080 in BH Crack
I’m pretty new to this game so I was just curious what is an acceptable level of tube Microphonics. My amp is on the lower shelf of my night stand and I use my phone as a music player. With the last 2 tubes I got, if I put my phone down on my night stand, the tube rings. With one, if I put my glasses on the night stand it rings. The second one is really bad - even if the headphone cable touches the night stand it rings. I can use and enjoy the first one, but the second one always has me distracted thinking about the ringing.

Returning a $20 tube that costs $6-8 to ship each way seems ridiculous, but so does dealing with the noise.

Thanks for any thoughts/comments

[Paul Birkeland]

If you're asking about the 6C45PI tubes in the Mainline, this is pretty normal behavior.  If you're talking about the tubes in the SEX amp or the Crack, that would be a little abnormal.

[Joe Garfield]

Whoops - it’s the 6080 in the Crack.

[Paul Birkeland]

Microphonic 6080s aren't as common, but that's certainly something that's pretty hard to screen for in testing.  I would just put some weight on top of the power transformer to keep the amp more settled, and that should reduce what you're hearing.