recommendations for tube dampers???

Chatta,

I'm sure urethane can work, but make sure it's of a formulation that will withstand the temperatures of a hot tube. I received a used preamp once with urethane dampers and they were a sticky mess. No idea how long they'd been in use, but they weren't doing much damping by the time they got to me. I stick with silicone just because I know it's one material that will stand the heat.

David

I concur with Gino. Silicone O-rings are dirt cheap and may be all you need. If you're not satisfied with the results, you can then move on to the more involved/expensive solutions. Upscaleaudio is also correct that a little bit of microphony can be a good thing, and is probably one of the reasons we all like tubes.

David