Anything you can put between spikes and carpet?

Thanks for your response. ZD, that's actually not the case. The spikes are very slim and adjustable. I've got them set up that the total of the brass footers (about 1") and the spikes is 2 1/8 inches long. I like Photon's idea as a starting point: simple, cheap, and non-invasive to carpet and floors. I may start by trying that. I am concerned that with the stone not coupled to the floor that it might induce resonances, but I suppose if I get a heavy enough piece of stone...

Great responses, thanks. Anyone else?

The other thing I did, just last night, was to adjust the way I had the spikes set up. I guess since I bought them last year, I had the rear spikes significantly lower than the front ones to angle drivers back. This had been a sonic benefit with every other pair of speakers I've owned, especially the ones I had just prior to these, Spendor S8es. By accident, I was kneeling on my own listening chair with my head elevated above where it would be listening, and I noticed that the soundstage was much more coherent, forward, and three dimensional. Just to see what would happen I tipped the speakers onto their sides and adjusted the spike - front and back - to a uniform 2 1/8". Back in my chair with the adjusted spikes the soundstage coherence I'd heard while kneeling was still there and on the whole much improved. We'll call that a good thing found completely by accident. Still have to work on that bass though.

Thanks. the only big difference is, I no longer have the Spendors - though they were a great speaker. I had an opportunity last summer to pick up a pair of Verity Fidelio Encores and took the plunge.