You might look at a company called MinusK Technology. They build isolation platforms for instruments like electron microscopes.Their products are not inexpensive, but they are less expensive than air suspension systems, and MinusK platforms do not require a compressor. I have used one of their products for a couple of years, and it led to a considerable improvement in sound quality.
I am not a dealer or affiliated with the company.
http://www.minusk.com/content/products/standard/bm-8.html
I am not a dealer or affiliated with the company.
http://www.minusk.com/content/products/standard/bm-8.html