From Denafrips Pontus to Lumin

is it better keep dac and streamer separate?

Pros and cons to both approaches.

THE Only Way for you to know is to bring in the Lumin and compare it head to head with your current front end source chain.

my Denafrips Pontus (with sotm 200ultra / sotm500 / sotm tx usb ultra)

What you have is very good. I recommend separating the sound quality/ performance choice and the convenience (all-in-one) choice and evaluate each on their own merits. There will be compromises / tradeoffs, no matter the outcome, and only you can make that call.

I’ve chosen to go with separate components for my source needs / requirements (computer audio front end) and have a mix of Small Green Computer / Sonore / SOtM / SR feeding my Denafrips Terminator DAC.

All the best!

@david_ten  thanks. With Terminator are you using USB or i2s?? 

@paoz  I'm using USB, only because I was already heavily invested in it and have optimized around it over the years.

If you have a choice, I2S is excellent as well as being a much less 'pricey' path.

I use the Innuos Zen 3, as a streamer and hard drive to store my CD’s, into a Denafrips Iris DDC and then i2S from that into the Pontus. I love the Denafrips sound.

@paoz what are you using for control app? Would you use Lumin app via UPnP if you make the switch? 
Asking because while I preferred the Lumin app over many other UPnP/DLNA options, changing to Roon was a revelation UX-wise. If you are considering similar, that might affect your decision on the hardware. Cheers,
Spencer