Using platforms / shelves under floorstanders?

Have had good success with a platform placed under my speakers.The material used to couple this platform to the floor will change the perceived sound.The best option IMS was the triple-point.

also Taoc in Japan has a variety of these....

I used Brightstar BigRock platforms under my Contour 5.4's for quite a while, and they worked ok, but I found they work much better under my source components, where they actually do some good. I am using the supplied spikes, and they are a pain in the butt when moving speakers around. I just remove the spikes when I am going to move them. I really haven't noticed that big a difference with or without the spikes, but these are only about an inch long when out as far as they can be. Try them without the spikes, and see if there is a difference.
You may find it is negligable.

Dan

I use maple platforms that are custom built by a member on this site (Monobloke) for my Gallo 3.1's and am very satisfied.

It depends what your floor is made of. If it's concrete then maple platforms might bring some improvement to the sound. I have the Mapleshade platforms, on concrete floor, and they do very well. But using them without spikes wouldn't make so much sense, I imagine, because you'd lose the coupling to the floor.
One way to prevent damaging woodfloors because of spikes is to place Yamamoto PB-10 footers under the spikes. They're imported by Venus Hi-Fi, and you'll find a review of them on 6-moon.