I've had my Rel Q200E on a 1ft square paving slab which sits on two pieces of wood (18mm x 69mm x 290mm) which have some rubber stapled to them. I'm using it as an isolation platform of sorts to stop my sub from vibrating the loft floor too much. Out of curiosity, I bought a 'Gramma' isolation platoform to see how it compares. Structuraly, it looks like a 12mm piece of MDF with carpet stuck to it, and two strips of thick dense foam attached to the bottom. I've yet to see how it compares with my platform. The only other difference is that between the two foam strips, there's a filler of diamond shaped foam - I assume to somehow attenuate any soundwaves that may come through the mdf base. Looking at the construction, and provided the two types of foam is readily available at good prices, it should be simple to build one, and probably cheaper. I'll try to take some pics so others can make their own if they like - custom sizes would be relatively simple if you have a jigsaw/circular saw. I'm sure I've seen the foam stuff available from PC modding places... Gary.