There seems to be two main components to these contraptions - a wooden board and foam. Is the board necessary from an acoustic POV? Or is it just there to create a solid platform?
I have a piece of very dense foam about 2” thick that I sometimes use under my bass cabs (2x Aguilar DB112s). It’s just the right size to fit between the feet of the cab. I’m wondering, if I glued a larger piece of carpeted plywood to it, so the cab’s feet sit on top of it, would it perform better sonically?