i have used them in the past in a tube phono stage and found they helped in some way and hurt in others. Less body more focused. I have several of them laying around, let me know if you would like to try them, I can send you some.
IERC Tube shields?
Anyone ever use these instead of tube dampers, tube sox, o-rings, etc. Consist of metal cylinder with finger springs inside, mil-spec for shock resistance. I have some Siemens that sound nice in my VK3i, but one of the four is microphonic and I wanted to try something like this out.