Why am I experiencing listener's fatigue?

you have a great system. but sometimes different is better.

The Monster Power will not cause fatigue, thats a stupid statement, so many people here throw Monster comments around like BOSE, and most have never had any real experience with it.....just stupid

My hunch would be the following:

o If the B&W 805's are monitors, you're already looking at an unbalanced or presentation weighted toward the highs. Consider either a set of full-range speakers and/or adding a subwoofer. Addressing this area could be a signifanct contribution to correcting your problem.

o Don't underestimate the significant contributions properly located speakers can make.

o Experiment with other line conditioners, ics, and speaker cables.

o Try removing all hard-surfaced furnishings and wall decorations from the room including leather chairs/sofas, end-tables, lamps, pictures, etc.

The list is near endless. But addressing one or more of the above could provide startling improvements.

-IMO

What is the Manley rated for? The B7W's like a lot of juice to bring the base in.

You are probably midranging yourself to death. B&W, tube equipment, Cardas all have reputations for great midrange, but a bit laid-back sounding. You might need more excitement at the frequency extremes. If your rolling off the ends, you might be turning the volumne up to make up for the lack of excitement, and the loudness might be causing the fatigue. Maybe some of the tubes are weak, which would also contribute to this. This is just a suggestion, as I'm not familiar with all your components.