Ideal material for wall mounted TT shelf

Many thanks for your responses. This is a dedicated basement listening room with the TT mounted on a RCC wall that is part foundation of a 3 story building.
According to my architect friend as this is a load bearing wall there should be no problem supporting the TT platform.
Halcro
If you see the long shot of the system facing the gear you can spot the brass cantilevers under the TT shelf etc. You make an excellent point that the TW AC is already decoupled via its cone feet. The AC also rests on a HRS S1 iso platform. Changing the shelf material from MDF to say a compact plywood with a laminate may yield minimal sonic differences though I suspect the plywood is more rigid with lesser possibility of any warping etc
IMHO the switch from a floor stand to a wall mounted shelf took my vinyl system to another level
Cheers
Pradeep

A quick update. I replaced the MDF shelf with a plywood shelf consisting of 6 sheets bonded together. To look at its almost the same. Using my standard vinyl demo disc - Shelby Lynne "A little bit of loving" there is a clear tightening of notes. The drum thwack in the opening track is taut and with a certain crispness. It's premature to judge the set up on the one LP I have managed so far, but its a step in the right direction.
Many thanks to all who chimed in
Cheers
Pradeep