Vibraplane 2212

I need a larger footprint than the Vibraplane's standard  24" x 20" top surface.  Can I place a 30" x 24" platform on top of the Vibraplane without losing the Vibraplane's effectiveness?
Have you looked at the MinusK products? I believe they offer larger-sized isolation platforms.
Probably depending on the material. You should call Steve Klein at Sounds of Silence in NH and discuss with him.  Vibraphone offers larger models as well