kumizi
I would also like to see more professional reviews with A/B comparisons between the D-1 and other DACs.
FWIW, I did listen to both DACs, but under very different conditions, so it's hard to extrapolate too much.
I tried the D-1 for 2 weeks in my own system, thanks to the gracious support of Danny McKinney. I came away very impressed. IMO the D-1 is one of those few 'step-function' innovations, which truly pushed the boundaries within a category (DAC in this case). I would argue the same could apply to Silversmith Fidelium cables. Not sure if Allnic's OTL/OCL preamps would also fall within that category, or whether they are just an example of masterful design and execution within an existing paradigm.
I listened to the Tambaqui DAC at a dealers, in a full Mola Mola system with Piega speakers. A very well-put together system overall, but harder to isolate the effect from the DAC vs the rest of the system. We put the Tamabqui then in a few other systems, including Accuphase and EAR (closer to my Allnic system than Mola Mola). I really liked the Tambaqui but was more in awe than in love with its sound. The Tambaqui offered great resolution and speed, a lot of detail, a very 'airy', extended sound, but was somewhat lacking in body and timbre , for my tastes.
If I could have multiple systems (audio fantasy) I would love to have a Mola Mola type set-up. If I can only have one system, I'd favor a more organic sound.
De gustibus et coloribus, etc.
I spent much more time with the D-1, in my own system. Compared to my impressions of the Tambaqui, it had a similar airy extension into the highs, but with even stronger, better-defined bass, and greater resolution of tonality in the mids. Voices and instruments sounded very layered on the D-1. I.e. for me, taking into account the different listening conditions, the D-1 beat the Tamaqui at its own game and then offered other qualities too.
During the same 2-week period, I also tried the Allnic D-15000 DAC and L10000 preamp in my system. Both are amazing, in very different ways from the Imersiv.
Paradoxically, perhaps, the obvious strengths that the D-1 and the D15000 DACs offer, led me to delay my upgrade decision. Each DAC is so specularly good at a specific sound quality (tonality for the Allnic, resolution , bass & imaging for the Imersiv) that it is hard to give up one for the other. I really want a DAC that offers both and hope such a DAC will become available 'soon'ish.

