Importance of a DAC's elements

I recommend looking at this from the high level / sound quality perspective. Merits of the particular technologies… say R2R… etc. become irrelevant in the larger picture of the design of the component and each subcomponent chosen within the box… well, for that matter the box as well. So concentrate on the overall components.

If you want to assemble a good sounding system. Then you will want to concentrate on a streamer box and DAC to plug into your preamp. While there are many combined units, they severely limit flexibility in upgrading and generally do not sound as good as separate boxes (too much stuff crammed into a box). Since streamers are a bit newer than the DACs… it is hard to get the very best streamer and DAC in the same box at any given price level.

Choosing the right streamer / DAC will depend on the rest of your system. As I have built systems over the decades typically I end up with a system with each box very roughly of the same cost. You cannot make decisions based on cost… but very generally they reflect the amount of design effort, component cost, and assembly time. So, just generally. I bring this up, because folks tend to think that going cheap on the streamer is appropriate… it is not. It is every bit as important as the preamp or amp.

I have experience with components from the $500 to over $20K… more on the high end than the low end (see my virtual systems). But I can assure you that as you move up… say from the $1K component, doubling the investment repeatedly to over $20K there is a very profound and important improvement in the sound quality at each level (if you have done your homework and found the best for the price, compatible with your equipment and tastes). In general, all aspects of sound quality improve: transparency, tonal character, detail, noise floor, dynamics, imaging, rhythm and pace… etc.

I highly recommend looking at Aurender streamers… at the highest level you can afford (I own two). Each level up is a significant improvement in all aspects of sound over the lower. A very high quality DAC is required as well. I like Audio Research, and Berkeley… although there are a number of very good DACs for over $5K

Listening is the best way to evaluate, but this requires experience. DACs like other audio components are easily broke into hyper detailed vs natural / musical. Many folks want detail at any cost… the problem for me with that is they often remove the music and natural sound and they become sterile. Reading and listening, be cautious of reviews touting highly detailed / analytical or you can end up with a scientific instrument for extracting detail that does not make your foot tap and is without emotional connection.

I think you might drive yourself nuts getting too deep in the weeds on individual product details, but if you enjoy that by all means have at it. I always start by identifying what sound characteristics I’m looking for, and then once I have some promising candidates I’ll look a bit further into design details but the final arbiter will always be sound. I mean, who cares if a DAC or streamer uses this design or that part if it doesn’t deliver the sound qualities you’re looking for? Now, if I’ve got a couple products like, say, DACs that are pretty much equal on all fronts and one offers a beefier power supply, galvanic isolation on the USB input, etc. then I’ll use design/parts to help make the final decision, but delivering the sound I’m looking for always takes precedence otherwise. Just my $0.02 FWIW.

Many DACs have various output analog stages just like preamps and those do bring the most of difference. Digital domain is pretty much standard and certainly less contributing to the SQ. Just like in preamps priced anywhere from few to gazilion DACs can be built differently by different designers with different materials and certainly different looks. To me $2500 is where should be the best DAC priced that is built from best materials and technologies with tube or solid state output stages. Also having all various types of digital inputs for multiple components. 

From my perspective streamers are simply purpose built computers that provide a digital signal to your dac.  That can be as simple a single board computer like the Raspberry PI to some of the ultra expensive highly modified computers that go as far as to supply three separate power supplies for the the voltages required to process your signal.  They refine the internals and isolate the output to unimaginable levels. 

Allo who makes streamer hats (and power supplies) for the Rasberry PI emphasize  how less than clean power can degrade the sound.

From Allo website: "The Digione Signature needs 2 PSUs to run.
We strongly recommend you purchase the battery pack or use a very good power supply for the clean side."

The other difference, the software interface.  It's ease of use and whether it supports your streaming service or the OS you are going to use to control your music. For instance the Lumin control software doesn't have Windows PC version.

I've not stepped up to an expensive streamer.  The major issue for me (besides the money) is that the support for Amazon Music.  I also haven't completely explored getting the most out of the streamers I'm currently using.  I do think that both the streamer and dac are important and providing the best source will pay dividends on your systems performance.