Isolating the listening chair?

Lately I have tried using audio isolation devices on the feet of my listening chair, first trying Tip Toes, then carbon fibre cones, suspension couplers and composite materials. I would have to say that the differences in sound quality exceed those in using the same devices on my tube amp, preamp, CD, or record player. I am now experimenting with different materials to put in the chair cushions, sand, closed cell foam, natural lambs wool, etc. The initial results are quite promising. Has anyone else had experience with this in the context of a high-end system?