Which DACs are known to be sweet/rich/relaxed?

The best dac’s I owned/had: Metronome Technologie “Le Dac” / C6 signature/ C8+ ,Ear Yoshino DAc 4 , and Audio Note dac 4.1x ( all dac’s with tubes!

@robert1976 

i guess there are just several things i would address before a dac. Perhaps you have already addressed them. Dedicated line was great. Good on you. So many don’t have a clean source. Ignore the slamming of this. It is so important. Also you are building a great system. Most of what you already have. Synchronicity is so important and trust that. Use your gut instincts on that. They are probably right. I have found that set up by a great system set up guru is so key. It was a whole new system after I had a top set up person come out here. Changed EVERYTHING. For the better. Build the system bottom up and enjoy. Yes though, please consider a great speaker/system set up person. Game changer and maybe the best component I ever added to my system.

With your budget, you really need to clean up your USB connection between the Nucleus server and the DAC. Think Singxer SU-6 or similar (or better). That is your current weak link and will continue to be no matter how much you spend on a DAC. 

Try a Musical Paradise MP-D2, get the DAC chip upgrade, Jupiter Copper Foil caps, GZ34 rectifier and 6SN7 tubes. That ought to do the trick.

@x5owner1 I don't use USB. The Nucleus connects to a wireless access point via ethernet. The Tambaqui DAC is a Roon endpoint and connected via ethernet to the same wireless access point. The Nucleus acts as a server only, the playing/rendering happens in the DAC.