Improving a stone rack

I usually improve stone by getting more stoned. Works for me great!

I tried a granite slab under my turntable a few years back and it had a considerable negative impact on the sound quality.  I tried it in three modes—alone on top of the concrete block pillars (see virtual system), on top of, and below, a 3" slab of maple. The poor sound was present in all three modes. It was a relief to remove it. My back was not happy. I was amazed at how poor it sounded. 

I have experimented with isolation materials. Hard surfaces like granite, glass, etc is going to emphasize the treble freq. Soft material IE Vibrapods, sorbothane will soften the highs but often at the expense of clarity. Muddy sound come to mind. A tone wood IE maple is the best I have found. I've also used DIY roller ball  type footers with good result. I recently changed from those to springs and saw no degradation to the sound.

I have used Granite for many Years as Sub Plinths for Audio Equipment on Racks and as a Cabinet Speaker Sub Plinth.

I find I prefer the sonic that has been created when using it, when the Granite is a Sub Sub Plinth or a Sandwich Material in a Build up of Materials to create a Plinth or Sub Sub Plinth.

For Speakers I always uses a Spike Coupling and Pneumatic Footer to create some suspension.

On the equipment Rack, I always use Cork as the Isolation footer for the Granite when in a Sandwich or as a Sub Sub Plinth.

Other Materials used in conjunction with the Granite will have  a selection of Footers tried out to discover which tidies up the sonic to a standard I am happy to experience.

Today, my usage of Granite is seemingly being superseded by the use of Phenolic Resin Densified Wood Board Materials, such as the Board Materials from the Brands Permali or Panzerholz.

I recently bought a rack from Acora audio and the shelves are African black granite. The underside of the shelves have some type of anti-resonate material attached to it. I always wanted to upgrade from my 20+ year old Target rack. I was thinking about the aesthetics of the new rack but the improvement in clarity, resolution and musicality has taken my sound up a few levels. I had my doubts about buying a granite rack but when it’s done right, it sounds great. Try reading some info regarding Acora’s racks, you might get some insight on what to try.