Floorstanders on wood floor, help

heavy solid rock or concrete slabs are the best idea, over spikes or pads... the speaker spiked to the 75 lb to 200 lb mass of rock or concrete... works for me in my apt. (I use 2' diameter 3" thick 100lb slabs of black painted concrete with three tiptoes into the carpet, under my speakers... keeps the bass out of my downstairs neighbor's apt.)

The slabs are a good idea, as are Symposium or Audio Resolution or other "draining" shelves. Actually, the shelves over granite slabs may be an awesome combo !

I have granite blocks wqith shelves, for my VMPS monitors, and they do a great job.

I second the big hunk o' rock idea. Even soneting that's 20lbs should help. I would try spikes or cones under a paver slab then compare the speakers on top with spikes and some isolation. I would recomend something other than sorbothane. My experience with wood floors (no carpet) was that bass energy was going directly downward to the floor and then acting like a drum as you describe. So I only worried about verticaly transmited vibrations, and used a platform which I isolated then spiked the speakers into the platform. For isolation I used:

http://www.mapleshaderecords.com/tweaks/isoblocks.html

I bought mine cheap from a supply store that sells parts for heating and cooling contractors. I guess they are commonly used under compressors. They are firm enough that you speaker will not move (clean attack), but they stop most vibration from getting to the floor. With a paver stone the absorb the rest you should be set.

Nik

Sistrum speaker platforms.

Are you sure its not your amp or other component IYS?