cones under your tube amps??

I would expect that a Promethean Base from Machina Dynamica would do a better job, but roller bearings under tube amps work well.

I use BDR cones #4's under my tube preamps with very positive improvements in all areas.

I use Sistrum platforms under my amp and preamp, and Audiopoints under my phono step-up transformer. They work very well for me.

Disclaimer: I work for a comapany that makes vibration transfer products.

I second BDR, a combination of (1)#3 and (2)#4 worked well for me under my VAC 160 Mono's.

My Wavelengths come with BDR cones as feet. They seem to work fine. I've tried replacing them with Stillpoints, but heard absolutely no difference.