I am long past the age when I could hear such fine distinctions as you are making, but let me ask a question and make a suggestion. Is there any other way you have found to produce "that warm holographic sound"? If so, then I would go the Poly cap route because it is neutral and your putting it where you hear it all the time. For those times when you want the special sound, switch it into the line up so that you can also switch it out when you don't want it. Like a "tone control". Bob Carver had a circut once that was claimed to produce such an effect. I never heard it, but some liked it, some didn't. -Dick