if I can remember hte steve dash involved consoles correctly, the turntable suspension was constructed as follows:
1. the platform for hte turntable had a downward extruding box of more ply. How deep? It seemed like almost the size of a turntable road case.
2. Open eye hooks were installed outward at the middle positions of the platform.
3. Open eye hooks were installed somewere at the corners of the box extrusion.
4. Open eye hooks were installed downward at the corners of the console surface hole.
5. Rubber bands connected the console corner with the mid-point hooks, and connected the console hooks with the box corner hooks.
This seemed to eliminate feedback with 2 15" reflex subs in the booth, and any number of bertha subs on the floor. It is a lot of work, and the rubber bands do fatigue over time. Other elastic connection methods might be longer lasting. The midpoint connections allowed for lateral sway, and the vertical points to reduce the load the lateral supports endure. Just like hanging speakers, the further one gets from a dead hang, the more and more tension once has to support.
It never seemed like djs particularly enjoyed the swaying decks. House djs who let tracks play out, cueing and recueing before mixing intros/outros seemed to tolerate it, but any djs manipulating the tracks more quickly, or simply any record manipulation loathed it, with some techno djs going as far as stuff bar napkins between the console and platform to reduce sway. The better the sway reduction so went feedback suppression, and these djs played exactly the type of music which benefitted most from feedback suppression- a lose-lose situation.
It has been over a decade since I've encountered such consoles. When I moved, I did have sonic success with rolls of tape or cut plastic pipe with wrapped rubber bands, but the djs did not like the bounce. Squash balls sitting under slabs of stone or steel are standard here. The balls also need periodic replacement, and are more expensive than rubber bands, but the decks sit still. I've injected standard caulking silicon (wear gloves, it is messy stuff) into a muffin form for cheap effective footrests, but just as important as acoustic isolation, so is keeping the surface the turntable sits on from moving, and this is where the concrete or steel mass comes in handy.