brass/wood cones under cd player

[lomarica]

does anyone have experience with placing brass or wood cones under your equipment or speakers. I have seen these for sale and have always wondered. It sounds like a gimmick but the idea is to isolate vibrations.

Mapleshade states real maple is the way to go but others use brass or exotic materials.
Music direct has a whole bunch of them all with a 30 return

thanks for any replies