Microphonic from Vacuum Tubes?

HI,  I have a question regarding microphonic from vacuum tube.  I have a Cary SLP-05, and I've changed the output gain tubes to some NOS RCA, and also recently purchased a pair of Linlai for the balanced buffer stage.

I now occasionally hear a loud pop in the music.   It doesn't happen very often, but when it does, it is quite loud.   This happens when I am streaming digital music, so it can't be those occasional pops you hear from vinyl.  

Can someone tell me if this loud pop possibly caused by microphonic in my tubes?  if so, how do I track down which tubes?   My guess there is no easy way but change one tube at a a time, which can be extremely time consuming.   Also I don't own a tube tester.  I wonder that would help tracking it down.

Also I read something about vacuum tube damper rings,  would that help calming down possible microphonic?

I still  consider myself a newbie in tubes,  so any hep will be appreciated.  Thanks very much.


So far I've only experienced this issue while streaming from Tidal or my own MinimServer running on my NAS.  

@xcool Really! That is telling you something.

In that case play the LPs only for a week. If you don't hear any pops, I'd look into issues with your digital setup- as @acman3 points out, digital is quite capable of making loud pops!



I do not think tube dampeners would help popping.

If a tube is the culprit, I would find it and eliminate it. It means there is a big bursts of electrons jumping between the plates… that should not happen. I personally do not want any badly behaved tubes in my system just in case it foreshadows a failure. Although cataclysmic failure are uncommon, they are not unknown.

If a capacitor, would get that fixed as well.


I am not an electrical engineer, but have enjoyed and successful employed tubes for decades. I have never had a bad event. But I very occationally get a badly behaving tube and get rid of it.

Thanks everyone again for your advices and sharing your experiences.  I will post an update if I’m able to make any progress on tracking this down.   Who knows, it might not happen again 😄

I sometimes get a pop noise when a major appliance turns on….like the heat or air conditioner. I have 2 dedicated lines and it still happens sometimes.

Tube(s) getting too hot….all you have to do is wait for pop then generously spray all the tubes with water. The bad tube(s) will obviously be obscured by a cloud of vapor.