I'm sure it's just 1/2" MDF. What makes it work is filling it with sand. Then it weighs about 90 lbs. Tyler will custom make them for different sizes. I've tried many different stands including Grand Prix Audio, Polycrystal, Osiris (not the Giza but the one with the rubber air blatters...they leak), and Sound Anchor. I've found that the improvements or differences are very minor. What did make a bigger difference was using "Feet of Silence" under the amp. They are weight limited though, and the KR is too heavy unbalanced to use them properly.
By the way, the one criticism I have of the KR Antares is that it is very insensittive. Hard to use with a passive or a pre-amp without a lot of gain. But KR will make them with whatever sensitivity you need. I sold mine to a friend and ordered one with 1V sensitivity.
