With all due respect, I’d prefer the digital experts at Esoteric to hardwire what they believe is best for their units. Plug, play and keep it simple.
I couldn’t agree more. I used to have a K-01 and I found it sounded best with upsampling set to "Original" and filter set to "Off".
I have since upgraded to the Esoteric N-05 dac with the new gen AK chip and again, it sounds best with the same settings for both.
It has also been stated by Steve of Empirical Audio in another thread :-
I agree that a good preamp is more important than the DAC, however they are both important.
You need a great preamp to optimise an Esoteric's potential. It took me a while to find mine and boy, was it worth it!
Enjoy the Music!
J. :)