Point of diminishing return for a DAC

Once again millercarbon pollutes another thread with his constant shilling of Synergistic Research snake oil.  Please stop!

You can do much better by spending more than $2500 for a dac. $2500 buys you a mid-fi dac. The best dacs are of the FPGA type which costs more and you get upgrades that improve the SQ 1 or 2 times a year for free. Also, the better dacs have Ethernet network connections.
Also, you don’t need a dedicated music server for a number of reasons:
1: you don’t want any kind of server in your audio room
2: you don’t want to use USB to any dac, it is a flawed connection

your Mac mini is fine running Roon, just place the server in a different room and connect to your dac by Ethernet, keep it simple and provides the best SQ

I would second the suggestion with a streamer and a DAC. Mine are 1:1 at around 1.000 €. 
In terms of diminishing returns it is worth noting that many more expensive DAC are based on another technology. Many DAC’s around less than 2K are chip-based, whilst some more expensive are FPGA-based, which means upgradeable. So it is not just about SQ, but also Lifecycle cost. 

Since I have recent experience from Pi DAC through DCS Vivaldi stack, I might as well chime in. I ended up with an Ayre Codex fed by a Roon Nucleus. I have been quite underwhelmed by the Rendu products - Digital and lifeless, reminiscent of the recent McIntosh preamps.
The Codex was a massive step up in musicality, pace, as well as micro detail and soundstage over every less expensive option. Meaning full up grades cost nearly to over $10k. If I were to upgrade, I have to say the DCS Bartok is the most affordable DAC through which vocalists sound human.
As a side note, the R2R people and to a lesser extent the Chord people make me laugh. 1) are you really going to find two resisters that match?
2) a billion taps does not make your DAC sound as good as anything from DCS.

Well! I feel like I just finished my masters in DACs.   I’m very grateful for all who took time to comment!