Grand Prix Audio- Acrylic VS. Formula shelves

I'm in the process of ordering GPA Monaco amp stands and rack. I'll be running Rowland Model 6 monos and the Emm Labs CDSD & DCC2. I'll probably get the Apex footers for, at least, the equipment rack. Can't decide on whether or not to spring for the Formula shelves, and at which locations they are the most effective/worthwhile. Anybody compare the acrylic and Formula shelves? What are the sonic differences? Thanks, in advance, for your comments.
I have both but have not done a meaningful compare. The carbon fibre certainly seems more rigid, but I'm not sure that's a complete answer since the system, as I understand it, depends on a certain amount of flexibility to accomplish its job. I know Jim Smith swore that the carbon shelves were a significant step up over the standard ones.
That said, the carbon fibre certainly looks cool.:)


I did extensive comparisons between the Formula and Acrylic shelves and it was not even remotely close. The Formula shelves added far better pitch articulation, immediacy and background silence, as if I'd upgraded my electronics. Images were moire solid and three dimensional. Bass had more impact and specificity, as if I were going down a half-octave more in bass.

If you can swing it $ wise, the formula shelves are a NO brainer for your set up. I've used them with the EMM gear as well, and the difference was _not_ subtle.

Grand Prix stands owe their science to Formula-One racing technology, where small changes in materials and parts could be the difference between winning and losing. That appears to be the case in High-End audio as well. :-)

Hope this helps, Grant.
i own the GP Monaco rack and amp stands with Formula shelves and Apex footers. i have not had the Acrylic shelves in my system but i did set up an almost identical system to mine at the Rocky Mountain Audio Fest that did use Acrylic shelves and in my opinion i could tell the difference in ease and detail on the EMM Labs and darTZeel amp and pre.

the Formula shelves give you better clarity and a more refined sound. bass articulation and the 'boggie' factor is increased. these are subtle but significant differences.

one note; i have carpet over 6" of concrete. i bought lead shot and filled the posts expecting an deadened the sound.....took the flow right out. only use ballast if you have a suspended floor and it needs dampning.