HD 579

I consider discontinued HD330 (later HD465 I think) as the best on-ears I've heard, but they are pain to refurbish - no direct replacement for earpads or rubber/silicone headband strap (straps can still be in good condition though). There is a higher model HD340 / HD475 which I haven't tried, nor anything Grado. I consider the above to be better than 60Ohm Koss (not a comparison really), or the very popular HD480 Classic II, or some more current lower-mid level over-ears like HD559, but not as good as say HD555/558/579. I might pick them over HD599 though, just because I don't like the bloated tonality of HD599. So all in all, it is still not the level of hundreds of dollars, but very usable.

570S are the kings in that price range

There are dedicated subs for audio which is more useful, but the truth is for the majority of PC use cases, any decent set of headphones is good enough. I have an ancient pair of Sennheiser HD5-- headphones that are still awesome. A monitor or any other PC part from that era is basically garbage today.

Sennheiser’s HD500 series models used

The build quality feels so much better than the 5 series. It's a shame the HD550 didn't inherit the metal headband. I absolutely love the comfort and isolation with these. I use the 500BAM microphone for phone calls. Pretty good value as I got them brand new for $213 + $66 for the 500BAM.

I honestly really like the stock cable on the 620S and the 5 Series headphones. It's not a fancy braided cable, but it's smooth and the kinks loosen up fairly quickly. My only issue with the 620S' build is the glued-on headband cushion. Surely they could have come up with some other solution, like the velcro on the 490 Pro.

Sennheiser 500eries goes on sale or refurb often cheap. They lasted me about 15 years, hella comfy as they use a velvet cup instead of fake leather shite