What input did you use to the CH2, e.g. was it USB or optical when you did the comparison ?
For my serious A/B session I used them both on USB input, Hugo2 plugged into the wall using my most well known FLAC files. I also bypassed the preamp (edit: of my speakers' amplifier) for the Hugo2 in this session. I learned the preamp section on my amp isn't bad at all.
At first I compared the 2Qute on USB with FLAC with the Hugo2 on the same song, but on 320 over bluetooth. The Hugo2 still won here in depth and realism, even with the technical disadvantages. The margins weren't huge but still perceptable. Big complement to the Hugo2 here.
Only on my hi fi system (the ELAC BS244 go to very high frequencies, they have ribbon tweeters) I could hear the difference between the filters. I like them, the red ones mellow out the high end on some tracks when I think they need it meaning I can turn it up and enjoy the bass a bit more.
I would wait for more impressions from more users before coming to a definite conclusion. A/B tests are never the way to go, they may reveal minor differences in the short term but given time once comes to realize the whole is greater than the sum. I remember reading on the Dave thread one user bought a Dave and couldn't hear much difference when compared to Mojo in their speaker setup, I think with more time his thoughts have changed. Hugo 2's preamp is incredibly transparent and the PRAT makes the VTL 5.5 pre seem almost sluggish in comparison. Cymbals, drums, guitars, are rendered so beautifully and realistically that they have given me many What moments, blurring the line between what is digital and what is real. Of course, every system is not the same and the overall synergy and transparency of the system will have a lot to do with how the system sounds, YMMV.
Yes, the system is important. I think the fairest test in comparing what the Hugo2 with it's new specs compared to the Hugo1 (and thus the taps on the 2Qute) is to compare with the best headphones possible to get the best revelations.
I back the A/B method as a direct in the moment comparison as a fair test in my opinion, due to the human's brain only being able to hold onto the memory of the sound quality for not much more than a minute.
I'm not saying the other option has no value or is weaker, the emotional effect the better performing DAC can have on the listener of the music and thus overall experience can can be more amplify musical pleasure more than what the objective A/Bing might tell you. But I think that could even come down to psychology (which can be influenced by price) and personality. And with audiophiles, a lot of our sonic taste preferences for the best end up damaging our hip pockets, a personality trait most people don't struggle with and thus are happy with the cheaper lesser performing products, the margins for them don't have the same impact (or they haven't had the luxury to sit with and feel the long term impact so it isn't an issue, but fair enough). I think to keep an objective A/B method is important as it lets the personality traits step aside for a moment. The immediacy of the assessment has value for all personalities.
I remember A/Bing the Mojo to the Hugo1. My impression was that the Mojo was good enough and the difference didn't bother me (if I never had the 2Qute, the Mojo may have became my main desktop DAC as the differences between them were less apparent through my speakers + amp when I A/Bd them). A year or so later I A/B'd the Hugo1 to the Mojo again using headphones (HD800s both times), and the Hugo1 leapt out as heaps better than what I remembered the difference being. The Mojo to my ears became second rate with my IEMs from then on (which I now want to upgrade because I believe the SE535 are second rate due to more A/B comparisons using other IEMs with the Hugo2). Psychology must have had something to do with it, even if it was ignorance is bliss. There are plenty of personalities, tastes and synergistic matches to headphones that keep people happy with the Mojo. So I do agree with letting something sit for a while then coming back, the clinical nature of an A/B session still has its place to inform.
To boil my thoughts down, what makes sense is that sometimes a small margin can mean a lot given time.