I alluded to my basic issue in my post. For my ears, they are very fatiguing. They are very good phones and I can completely see how a lot of people will love these. They are impactful and exciting but for my taste, they push all the wrong buttons. To my ears they are thin and wiry with a shouty midrange. There is possibly too much separation and depth such that they lack coherence. In the end, they just don’t seem natural or musical. For $1500.00 they need to knock me out but time after time, I switch back to the HD650 and think ahhhh, that’s just right. Hope that helps.
And I do list an amp, the Simaudio Moon 230HAD which has paired well with a variety of phones.