How much does a DAC do the more expensive it is?

@simao you experience a wow moment after adding the Gungnir then pose the question, what do even more expensive DACs do better/different than cheaper ones like your Gungnir, then later you describe a listening session where an uber expensive CD player wasn't memorably better than your digital front end, which anecdote suggests you are persuaded by those posters here who state that there's no correlation in hifi between higher cost and the feeling the higher cost ALSO represents value-for-money. The Law of Diminishing Returns IS a thing in digital hifi, but the resolution of the rest of your system will determine whether you get a value-for-money feeling if/when you upgrade from the Gungnir to, for example, a Gustard R26 streamer/DAC for $2K. I guarantee you the Gustard is MUCH better sonically than your Gungnir, but whether your system can exploit that sonic improvement is something nobody here can say. You will have to take the plunge and listen for yourself in your system, there is no other way unfortunately 😕 

@simao great that you are satisfied with the Gungnir, I must admit it has been expensive suffering from upgraditis! My limited understanding of the technical design differences between expensive and cheap DACs is that power supply, isolation, and clocking are the key areas. I'm not an engineer so I can't assess design choices, but one look inside an MSB Reference was a damn convincing experience of what your money buys you when you spend $$$$. As an aside, it's interesting that "superbly" measuring DACs like my Topping D90SE don't sound as good as the more expensive DACs in my collection that measure comparatively poorly... whatever design and parts choices that lead to great measurements don't correlate with great sound necessarily.

@charles1dad yes it's obvious that if measurements captured ALL sonically relevant parameters then excellent measurements would correlate strongly with sonic excellence. One such parameter is soundstage width/depth - which set of measurements reliably correlate with a wide/deep soundstage? Answer: nobody seems to know. Why is there not more curiosity about answers to these sorts of specific questions amongst the measurements-first crowd? Even I would be interested in studies done to determine the answers, so one is left to surmise that crowd aren't interested really in science as much as they are interested in being right and trolling those who aren't convinced that the current sonic measurements regime is a completed field of study.