What a loaded question!
Akg k701s, ety er4s (plus amp and lod of course) for critical listening (classical mainly), monster miles Davis tributes for pop and most other genres on the go..
I've had so many headphones/iems over the years, it's really a great hobby to be into..
And if you're considering the beats, go to audiophile websites and look for comparisons to others. I've heard a few of their models (including their most expensive pair) and..if sound quality is your main concern - there's similar for much less available. Same for Bose, which I've also owned..
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