Should I upgrade from a Mac Mini to a dedicated server or should I upgrade my dac?

One thing I'm not clear on. Are you connecting mini to ethernet switch or bridging thunderbolt out directly to Moon? Mini direct out to Moon would likely be preferable. You're doing well by doing no rendering with mini, could still benefit greatly with powering mini with lps, such as Uptone MMK and JS-2. So take thunderbolt bridge direct out to Moon with quality power supply, add operating system optimization and you have first rate non rendering server, essentially you have network device. Would take really top flight server to beat this setup. The issue with all this requires much diy work.

@pgastone

Keep the Mac Mini.I have one and hate the MAC OS but you d not need to replace it to get great sound.

Read the John Swenson white paper on streaming. If you want to try his approach, get a media converter such as a Sonore OpticalModule, Uptone EtherRegen (use reverse), etc.. Then get a Sonore OpticalRendu to take the FibreOptical from the media converter int the OpticalRendu and then tale USB into the DAC.

If you want to save some cash for a slight los in quality then get a network switch that has a Fibre Optical output. Take the Fibre directly into the OpticalRendu and then USB into your DAC.

Fibre cannot carry analog noise like Ethernet can and pollute your DAC. I was under the impression that the very best method to stream was Fibre directly into a DAC (like Lumin X1 DAC) or second best the Sonore OpticalRendu. However, after reading John Swenson’s comments about adding a media convertor in front of the OpticalRendu I tried it and my tunes sounded even more focused so now I also do that for 2 or my 3 OpticalRendu’s.

Ethernet streaming is easier but most DACs do not have this and the DACs that I have heard with it sound better streaming via an OpticalRendu to the USB input of a DAC.

All the Rendu’s are ROON READY.

I’m using Mac Mini as a roon core (I think it’s the 2018 version with 128gb SSD). No issues. 
I would keep the roon core away from the system and use it purely as Roon Core. Then run Ethernet into the streaming DAC from either the router or an access point. In both cases use EtherREGEN or a network filter between router/access point and the streaming DAC. 
Now to your question…upgrading the DAC in your setup, IMO, will reward you with a more noticeable improvement than upgrading the Roon Core. There are good options for a streaming DAC that are certified Roon endpoints,  either within or outside of Moon product line. 

@mofojo: I agree that trying all possible combinations is simply too time consuming but I certainly will continue to use Tidal/Qobuz. through Roon....hence my question of what is the most reasonable upgrade path.

@jjss49: I am sure that everything ultimately matters to some degree but I like to move incrementally and see how the system evolves.  And since there seem to be various approaches I am just trying to get a sense from others who have more experience and expertise than I do on where they think is the best place to start.


@sns: thanks for the tip but yes this may be a little more DIYing than I would feel comfortable tackling.  And just to clarify the system is set up as follows
Router -> Switch (2 outputs) -> (1) Mac Mini
                                              -> (2) Dac (newtork/endpoint)
All these are ethernet connection- switch has separate LPS.

@yyzsantabarbara: this sounds like an option and I'll look at the white paper.  The move to optical would cost some $2-2,5k so this would open the upgrade choices to three- either mac mini or dac or optical stream ...sounds like your last option would be a better choice than changing the mac mini- would go that route also if the choice were between this and getting a better dac?

@audphile1: this is what I always thought but then several times others told me that I would get a bigger improvement by switching out the mac.  Even verdantaudio brought this up on his very extensive dac resting post when I queried him on some of the dacs he was discussing- and as a dealer I thought I should take heed because from that perspective he, or any other dealer would probably stand to gain more if there were to sell a high end dac,  I have to say I have always found his input invaluable,  In any event I was looking to get some more feedback,

And btw thanks for all the inputs thus far- all very helpful !! 

@pgastone  Moving to Fibre is at most $1500 on the Rendu lineup. I have 3 of them with LPS. Including a used one for half that price.

Baby step would be to get a network switch with Fibre output and a $1500  (or less) package of the OpticalRendu + LPS. You can get it for less and I do not think you need to get the audiophile upgrades (I have both the upgraded and standard).

https://www.smallgreencomputer.com/pages/systemoptique-certified

I have the ROON ONLY model since I do not do any else with the stream outside of ROON.