Shelf Help Lovan Rack

I purchased two 2' x 2' concrete patio slabs and a solid concrete bird bath pillar from Lowe's. Put one slab underneath, one slab on top. Total cost: $35. Previously I was using come cheap old wooden stand, which was picking up a lot of vibrations. This new home-made gave a huge improvement to the sound, and didn't cost much at all.

Here’s an idea; contact Valleyplastic (user name on Audiogon) and have him manufacture you a custom acrylic shelf or shelves, if and when he has time.

Kill the glass. If you like the look of glass, maybe finding some 3/4 inch to 1 inch thick acrylic. Tap Plastic should be able to help cut out the corners to fit the rack. When I first purchased mine, I ordered them with the MDF shelves. They are like 1/4 inch thick. That was a joke. What I ended up doing was sealing the legs and filled the with sand. I doubled the shelves w/ a layer of vibration-absorption vinyl. That actually worked well. I also got a few pieces of granites cut to fit, sandwhiched them w/ maple board(on top) and vinyl. These days, the Soverign racks have been moved to support HT gears as I've upgraded to other racks, fist to a Solidsteele 5.5, then to all SolidTech reference racks. Both times, the improvement were very noticeable. So I think you need to decide how much you like them, and whether you want to throw in any more money into this rack.

FrankC

One idea - replace your glass shelf completely with a Neuance shelf. You'll get noticable improvements in every aspect of your sound, especially under your table. I did this, one shelf at a time, and am thrilled with the improvements.
Google Neuance to find the link. Highly recommended!

Kill the glass completely. Go with wood. Sound on glass rings, rings.

Just to clarify the maple platform would rest on top of the glass

Personally, I think the maple platform will give you better sonics (anytime) over glass.