Best isolation device for a tube pre-amp

On a concrete base going directly into the ground, inside a soundproof room! You asked....

Seriously, probably the best overall approach is one of the isolation platforms with the inflatable bladders, on a good rigid rack, plus damping rings on the tubes themselves.

I've heard great things about the symposium rollerblocks are the aurios mibs. I have the rollerblocks under my cd player...major improverment. DH cones and pads under preamp currently. They help alot...don't know if they qualify as best though...

They may not be current state-of-the-art, but the Townshend sinks are very good.