That combo of Emo pre and power amps should be able to drive most speakers including the Ascend towers and remain neutral/accurate. If they don't, or can't, then then Emo is not telling us why, and/or all those reviews and lab measurements would be questionable, but I don't believe that is the case. When you get to that level of gear, one shouldn't have to worry about synergy between amps and speakers unless one owns certain uncommon speakers. Also at this level of price point and quality of amps, brightness or warmth would be more (not saying totally) determined by the source media. Other than that, I have to say Placebo could be at work in some cases.