Another thought on the subject.....I used a RS dB meter and sampled different frequencies around my room. I found that some areas had much lower sound levels at different frequencies than others. I had to use longer ICs, but placed my rack at the lowest "loudness" position. I also placed the amps on stands nearer the midpoint of the wall behind the speakers because this was the "quietest" place. I then mass loaded the mono amps and used points on the bases through the carpet to the concrete floor. Does it help? I think so, and it cost nothing.
Isolation for tube amps
I've read the some of the threads on isolation platform ideas for amps, but am wondering how one can isolate the amps (and other equipment) from ambient sound pressure? It seems that this would be the most predominant force to isolate? I don't know how anyone would be able to isolate one's components from this force unless the components were in the other room. Any ideas?