Listening Room or Components or my ears?

My older Wilson speakers have the Focal 1" inverted titanium-coated tweeters.   They have a bad reputation for harsh highs.   When I first got them, I concurred.   Not anymore.  Now, they sound sublime.   Zero fatigue.   The solution was cleaning up the AC power - with special attention to the digital components.   

All of the above suggestions about the room, room treatments, speaker placement, speaker toe-in are correct - as is clean power.   It takes a fair amount of tweaking to properly dial-in good SQ.    The distance between the speakers is based on several factors.  If they’re too far apart, the soundstage becomes defocused & delayered - a vocalist sounds like their mouth is 5 ft wide.

Here are assorted discussions.

Reduce all toe-in. Have speakers facing straight ahead. Worked like a charm for my B&W 803 D3s.

Facing speakers almost straight ahead does turn down higher frequencies and especially if the speakers are not far apart from each other. No toe in toward the main listener position.

Good Day

Thanks to all for helpful comments and suggestions. Much appreciated.

You've given me lots to think about and explore.

In my experience I have never been in an untreated room that did not emphasize the upper mid’s and hi’s. You also have a room gain imbalance with the right speaker being 15’ from the side wall, which will help de-emphasize the lower frequencies on that side. Also our ears are less sensitive to lower frequencies at lower volume levels. In my opinion you have three things working against you, but I think room treatments is by far the best place to start.