Fwiw, It's a demanding headphone, infamous for highlighting deficiencies in a chain. Your source also has to be equal to the task. It baffles me that so much focus is placed on amping requirements. Sure, the HD800 demands (a relatively high minimum level) of quality amplification compared to other headphones, but too often people put all their eggs in that basket. The possibility that the source component is the culprit is often overlooked. Careful consideration has to be taken with all components when building a system around the HD800. Anyone who has spent time with this headphone knows this. Those who haven't will regurgitate the old myths of grating treble, lack of bass and unnatural imaging.
I'd say thats the same with all good headphones. If any of the above (bolded) is happening with a modern mid price dac and amp, then it has to be a fault of the headphone (and maybe recordings) and not the equipment. Theres far too many comments on the HD800 needing certain requirements to calm the treble and boost the bass to ignore; And that would be called coloring the headphone, which is different to pursuing super high end transparency. But as you say.. this is for another thread.