I use a 3.5" thick 15"x20" Michigan Maple brand butcher block cutting board under my turntable. I got it from Overstock.com for about $90. Price fluctuates a little bit, but currently they offer them for $100.99 with free shipping. http://www.overstock.com/Home-Garden/Maple-End-Grain-20x15-inch-Chopping-Block/3300227/product.html?...
Mine fits perfectly on a Technics SL1210 M5G. It lowers the noise floor, improving dynamics, clarity, and inner detail. I mentioned this to an audiobuddy with a belt drive Music Hall turntable. He picked one up and was also very pleased with the results. Just putting the turntable on it helps quite a bit, but you can get even more improvement by putting some gel pads under the cutting board and positioning the turntable on Vibrapod Cones and Isolators, which absorb some of the mechanical before passing the rest on to the cutting board.
Mine fits perfectly on a Technics SL1210 M5G. It lowers the noise floor, improving dynamics, clarity, and inner detail. I mentioned this to an audiobuddy with a belt drive Music Hall turntable. He picked one up and was also very pleased with the results. Just putting the turntable on it helps quite a bit, but you can get even more improvement by putting some gel pads under the cutting board and positioning the turntable on Vibrapod Cones and Isolators, which absorb some of the mechanical before passing the rest on to the cutting board.