Best Carpet Padding

Don't tell her it might be better, act like it is a HUGE sacrafice and she might have to give back a little as far as the speaker placement goes!

Why should the floor be treated differently from any other reflective surface? If you heavily pad the floor then heavily pad the rest. If your walls and ceilings are reflective why should the floor be inert? Because emphasizing slap-echo is inherently preferable? Or maybe fine tuning comb-filtering for maximum interference is your thing? Less is often-times more, IMHO.

The floor should be treated differently because it is really close to the drivers and your ears and reflections off the floor will be the FIRST to hit your ears and smear your sound. The walls are generally further away from the drivers.

The other posters are correct in saying that thicker is better. Furthermore, you should use cotton or wool padding because the fibers will be of irregular length and diameter and will absorb relatively uniformly across the spectrum. Man-made materials are very consistent and will give a peaky absorption/reflection pattern. Enjoy.

So shifty (heh heh). There is no need for all the poker playin tactics. When YOU figure out what YOU want, put your foot down an' tell her how it's gonna be (heh) like we do down here in the great state of Texas(heh heh). They are much happier when you don't give them a choice. That way they don't feel resentful when it doesn't go their way (heh). Try it, it works good (heh wink)
Thanks,
W.

Metaphysics, I understand your point but think you missed mine. What you say about the floor's proximity to the drivers is of course correct. But overly damping the floor will simply change the SOURCE of the first reflection that hits the ears and thus smears the sound, usually to the ceiling or one of the side walls. There is ALWAYS a first reflection that smears the sound. Grossly imbalanced damping of parallel reflective surfaces can result in worse sound than no damping at all. Would you leave a left side-wall totally clear while treating the right side-wall with multiple inches of polyurethane and wool, simply because the right side-wall was closer to your ear? Why do the same to the ceiling and the floor? Is there something inherently different about vertical and horizontal reflections that I don't get? My experience is that BALANCED damping of parallel reflective surfaces sounds better than imbalanced regardless of the surfaces' spatial orientation. FWIW.