What isolation feet to use??

Honestly it really depends on your rack and the floor of your listening room (shaking wood flood or cement slab) and how your electronics were tuned.

In my system in my room (cement floor) coupling equipment to the shelves (maple)with spikes and the ayre myrtle cubes works best.

My recommendation is to play with home brew things and narrow down what improves the sound to you and then go from there.

Bubble wrap or a memory foam pillow will test isolation and wood cubes or large metal nuts directly under the chassis will test coupling. I second Herbie's as a source for cheap things to try. A big ziplock with sand under a component is also a quick and easy tester for whether your rack it self is the problem.

Take your time as I have found that different footers more often produces a difference rather than an 'improvement'.

Rakuennow, can you give an example of how you use that Sorbothane program? Looks like you have to input the footer size and that is what I thought the output would be.

Cheers

I have had great success with EdenSound Bearpaw brass cones and 2" Maple shelf .Also use a EAR Damping Pad between Bearpaw footers and equipment base...( Thor T1000 linestage ) ...

I've had excellent sucess with EquaRack products.

After having used Rollerblocks, Aurios (standard and Pro), Boston TuneBlocs, Sistrum platforms and Neuance shelves (one of which I still use), the product that produced clear results by reducing noise and clearing the background of grunge was Grand Prix Audio Apex footers. I now use these under my preamp and digital source with excellent results.

They were demonstrated to me by Steve McCormack when I was auditioning his VRE-1 preamp. Honestly, I didn't want to hear a benefit with the Apex footers due to their cost, but I did hear a significant difference (with the caveat that "significant" is impossible to quantify, and varies from listener to listener). The Apex footers made the music come alive in the room, and separate from the speakers, in a way other footers had not done.

I am using Herbies Iso-cups with lampblack balls under my Calypso and would highly recomend them.