Question on my real mullards

[samwheat]

I have a pair of xf3's ...... i can hear noise while holding them close to my ear when i shake them gently ..... they test with no shorts

what's loose or is this normal?

are they good to use?

[coreybox]

I had a RCA rectifier tube that did this same sort of thing. i worked fine, but when playing i could hear it star jingling. It was pretty loud, and very annoying.

I've never had lose stuff in power or preamp tubes, so i don't know if it would have a similar effect, but i imagine it probably would.

[Mike9]

Probably not a good idea to shake them - D)