Digital Upgrade Recommendations

I would first research what is the best digital input on the Pontus II. Some DAC's perform better with I2S, others with USB. This will determine the ideal device feeding the DAC. The last link in the chain before the DAC is the most vital; components further upstream can be isolated by streaming over a network–lessening their significance.

Owning a Roon Nucleus I assume you are using Roon? If the Nucleus is running Roon Core, it is not only playing the role of streamer but also the role of server. In this case I would suggest offloading the streamer/Roon endpoint duties to something like a Sonore ultraRendu or microRendu. Connect either of these devices to your router/switch/modem over ethernet, and as long as they are on the same network as the Nucleus you can use them as Roon endpoints. Then go USB into the DAC.

You can supplant ethernet with fiber optic for even better isolation, but cost and complexity increases.

@tom2441

i apologize, i was wrong, i misread your op, misunderstood your setup and assumed it is like mine

in your case, i do think that of the 3 choices you gave, you should get the ddc gaia and use i2s into the pontus - i had that set up, it worked well, improved the bass and imaging of the pontus somewhat, my pontus was fed by a bluesound node streamer as roon endpoint at that point

that said, @sonic79’s suggestion below is superior - don’t use the core machine as an end point at all, just have it do the processing/computing, data/file management, traffic flow - and then have an outboard streamer endpoint that is fully isolated via optical (sonore opticalrendu w lps, or equivalent - this provides the most effective isolation, better than the gaia’s electrical isolation) -- and then take the music stream from the opticalrendu into the pontus via its super clean usb output (this method is noticeably the superior to having the gaia take a very noisy feed from the core machine, then only partially cleaning it into the pontus - i tried it, sold the gaia, i determined the optical isolation was most effective, produced the most easeful sound)

in the way of explanation for my error, in my current case, i use a weiss dac501 -- this works as an endpoint with dac, it takes the ethernet feed from my dedicated core -- in this case, i chose use the uptone etheregen to clean/isolate the ethernet feed into the weiss, and the weiss does the rest

hope this explanation is clear, sorry for the confusion

Audiogon Discussion Forum

As a first step buy an Intona Isolator and cable for your USB connection. After that improve the power supply to the Nucleus or buy a better server such as Auralic, Aurender, InnuOs or Lumin

Thanks everyone for all the great suggestions so far.  The Nucleus is running solely as the streamer as I have the Roon core on a separate computer in the office serving all of the Roon endpoints in my house.  So that one I've done already.

JJSS49 - thanks for clarifying your setup.  Good to know you had an improvement going I2S in the Pontus.  Did you have the Etherregen in at that time or did you add it later?

Sonic79 - I think your comment that "The last link in the chain before the DAC is the most vital" is very important.  That's why I think the DDC would be the best place to start for upgrades.  There have been many reviews of that combination online all stating strong improvements in performance.  Besides, doesn't the DDC effectively have the same benefit on the signal as the Etherregen?