hmm, the Harman Curve for headphones:
these guys spent a lot of money testing hundreds of headphones on hundreds of people to find what was the most pleasing sound combination across as many people as possible, then they came up with the curve that represents that sound signature.
any headphone coming closest to it, should in theory, produce the most pleasing sound, be it cheap or expensive. i actually think it's true, i mostly listen on n5005 and i love the sound signature -- maybe there is a tiny bit of of too much bass for my taste, i suppose i can swap out the included filters -- but otherwise i'm a big fan of the sound across many genres of music.
interestingly enough, for truly portable situations i use my beats wireless -- and i'm saying it only here because it's sound science and i feel safe saying it -- i think they're extremely underrated headphones and sound amazing. i looked up some of their sound profile and when compared to the Harman curve they were very close. there are internet posts that you can look up if you search for "headphones closest to harman curve".