I once owned Sonus Faber Extremas that had the Dynaudio Esotar tweeter that is absolutely incredible. I now have a pair of Merlin VSM speakers that also have this tweeter. They are top of the line tweeters.
What speaker has the best tweeter?
I love the AMT tweeters in my speakers. They are definitely different from other tweeters I have heard. I enjoy their openness and air. But there are qualities of other tweeters that excel in other ways. Some v pricy speakers use beryllium or diamond or diamond coated beryllium. I see that the price of, Seas I think, diamond tweeter is like $6K a pair. Then ribbons offer used. Not to mention plasma, etc.