Hi, Ryan. Isolating each of the components on a rack is always most essential, regardless of the integrity of the rack, and should be given first priority. No isolation method or product at the individual component is 100% efficient though, so isolation/decoupling of the rack is additionally beneficial. Component and rack isolation are both needed to achieve a whole result.
Isolating only the rack will not achieve a whole result; components each self-generate micro-vibrations that permeate the rack and other components, inducing audible distortion. If you upgrade to the world's finest and most perfectly isolated rack or platform, you might not have accomplished a whole lot if the components are still on their stock footers.
If isolating components with rigid coupling devices like cones or roller bearings, which often function more as "tuning" devices than true isolation, the rack integrity and character is paramount. Conversely, with decoupling isolation as Herbie's products achieve, rack integrity itself is much less important, though the rack still contributes somewhat to the audio palette.
A suspended hardwood floor is virtually always problematic to rack integrity, with resonant "house" and appliance vibrations, speaker and acoustic-generated vibrations, component-induced microvibrations that reverberate back up into the rack, and others.
A Big Fat Dot placed under each leg of the rack will do very well to isolate the rack on a bare floor. Big Fat Dots should be sufficient, though Extra-Large or Giant Fat Dots would provide even more vibration absorbing and blocking "beef." Giant Fat Gliders could also be used instead; Giant Fat Gliders provide the same isolation/decoupling benefit plus allow easy mobility of the rack if you ever need to move the rack a little and can be used on bare floor, carpet or rug.
Steve
Herbie's Audio Lab
