Ears hurt when listening after changing speakers

I would add one more thing. The kind of fatigue you describe could also be caused by bad or shorted interconnects up stream, causing a real low hum. 

That beryllium dome could be making you a little jumpy. I had been a dealer for Merlin's until I realized that the Esotar tweeter was so bright I couldn't stand to listen.  Sold the demo's and discontinued the line. I never want to let a customer suffer through that or myself. 

Hmm. You think Dynaudio Esotar tweeters are bright? Never heard that before. 

mofojo

I attribute that to my excellent hearing.........lol

Brighness is a matter of balance, so involves the entire system, not just the tweeter.

I haven't heard those speakers, but I am sure I can make speakers with any drivers sound bright. 😀

I can't suggest a reason, but I had a similar experience with a pair of Golden Ear 2s.  I finally had to give up on them.  I have owned many brands and sizes of speakers and played all volumes and kinds of music, but only the Golden Ears had this effect.  It seemed to be some high-frequency causing it, but similar ribbon tweeters in Martin Logans don't produce that effect.