Node2i + Qutest or Yggy or Codex or something else

Since the budget is $1800 here are options:
if you want clarity and realism and detail then the Schiit Yggy used is a good choice. Someone also mentioned the Gugnir. Also a good choice. Those are both multibit DACs. The Quetest is also good and in your price range. It has different filters and is adjustable to taste. A quality product FPGA DAC that is built like a tank. Another good DAC you can sometimes find used (I did) is the Mytek (a chip DAC) Brooklyn DAC+. I don’t have experience with the Codex. But these are all quality DAC and it’s a matter of taste. 

FYI the PS Audio DirectStream DAC has digital volume control though the touch screen. So it can drive power amps directly without another preamp. 

Btw, I do have a collection of DACs which include the PS Audio DirectStream DAC and the Mytek Brooklyn DAC+. But I can’t give impressions on a comparison yet as I have not spent enough time with the Mytek yet.