Anyone Try this?

My system is not only on a hardwood floor but on a second floor. I have my speakers on a one inch piece of marble with thick felt pads glued to the bottom of the marble.
This certainly did the trick for me.

It just may work for you. I removed some Herbie's footers from under my monitors and sat the speaker directly on my maple stands and the sound improved dramatically.

The thick felt should protect the floor and have minimal, if any effect of it's own on the sound.

All the best,
Nonoise

There is a "spikist element" lurking around so be careful not to say too much about spike abandonment or you will feel their wrath. I de-coupled my Silverline Preludes from the wood floor with Vibrapods (on wood blocks to simply raise the tweeter level 4 inches or so…the pods are under the speaker's feet) a few years ago after having been a spiker for decades and man…works swimmingly and makes a lot of sense if you simply release your mind from the pokey grip of the Fundamentalist Spike Cabal.