Best material for an isolation platform?

A couple weeks ago I set my amp on a 2”x19”x19” slab of limestone.
$41
works perfect

I found Symposium Ultra Stealth edition to be the BEST by far after all you get what you pay for.Wood sounds soft and colored and granite rings like a bell,Good luck.

John Boos maple cutting board.  

+1 for Symposium. I use svelteshelves on Rollerblocks with great results

look at this question as including the rack and floor type. the isolation base is going to just be one part of the equation.

is the floor resonating with the music?

if you have a suspended wood floor, first thing is to consider is solving the flex in the floor. might be a number of ways to do that. maybe mass loading the rack with steel plate or a sand box might reduce the flex?

if you have a concrete floor then look at your rack. is it solid?

your isolation base will be compromised or optimized based on the floor and rack. and the more dynamic and higher the SPL's you like to play the more the floor and rack will limit you.

it’s all context with resonance control. no absolutes. first things first.