Full disclosure: for the last 10 yrs, all of my listening has happened on my desktop audio system, which I 've consistently upgraded. The powered speakers are next to be upgraded (Swan M200 MKIIs). They're quite pleasant, but not a top-level, audiophile design.
Regarding DACs: my 2nd DAC was the very good, inexpensive Peachtree Audio DAC iTx (I'm in agreement w/Vdotman about this unit). Still, I was restless w/"digital" aspects of sound on my system even w/this DAC. I got interested in R2R DACs. That led me to non-oversampling (NOS) DACs.
A Chinese company named Audio GD offers very well regarded R2R DACs (ie, DAC 19) and an NOS DAC, the NOS 19. Last summer I purchased the NOS 19. It proved to be a major detour in--and a major refinement of--my entire relationship w/digital audio.
What does it sound like? Well, digital "glare" is utterly gone. Transients aren't highlighted in the least. All the detail is there, but it sounds natural/organic. All the frequencies are there. I don't find the treble rolled off, for example...it scales up suitably w/a recording known to be bright). The midrange is just about perfect. And the bass has a very pleasing, rounded quality. I have a good sub and hear all the bass: it sounds very good.
I've gotten several high-quality headphone amp/preamps (Audio GD SA-31SE; Violectric V281). On headphones (multiple types), each sounds extremely good, albeit in very different ways. When I listen via speakers + sub, I hear all those differences, just larger. So I think the DAC is "telling the truth" in my system.
The NOS 19 is so good that I stopped thinking about DACs--no upgrade fever. I don't even think of the DAC day-to-day. It just does what it does, and music sounds better for it.