The speakers will have variations in bass response at various distances from the wall.
Only by getting them at least 18 inches from the rear wall will this variable be eliminated.
I have had speaker stands made up by taking a sketch to a local metal shop and simply telling them to weld a 3-inch diameter tube to metal top and bottom plates of the desired size.
This is quite inexpensive and works very well. You get the exact height you want that way, also.
Be sure to have them put a hole at least 1 inch in diameter in the top plate so you can fill the vertical column with steel bird shot or sand for mass. Cover the hole with tape after filling.
You can drill small holes in the base plate for attaching floor spikes/cones.
This will give you stands equivalent to the ones some speaker companies sell for $300 or so at a much lower price.
Edited by commsysman - 4/12/13 at 8:45am