Large brass devices on top of power amps ?

Most likely brass weights for Vibration damping.Vermontaudio.com sells a 3" brass damping disc..

Even though I am a fan of brass support BearPaws from edenSound and of Mapleshade's brass footers on their air dried maple board supported by isoblocks, any brass weight on top of amp or preamp leaves me cold.
The delicate harmonics are diminished leaving a more dynamic or forceful sound which is too stripped of shadings of sound character. Big and bold yet lacking subtlety.
Although this seems to be a minority opinion, keep in mind that the adding of damping weight should be tried with a return policy, just in case it is not preferred by you.

Listener57,
You raise an interesting point,is this theory or based on personal experince? is there some optimal weight/size that would dampen some component`s tendency to ring without harmonic supression? I agree that harmonic information is very vital and it`s absent is noticeable.