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

Good to hear some other folks own an Audio Research Ref CD9se… an incredible DAC that gets the details and nuances in order with exceptional balance and musicality.

Mine has really profoundly influenced the sound quality of my system in all the right ways.

I'll probably be castigated for this recommendation.

Before you do anything, install a dedicated grounding system and connect it to every metal case with a separate lead back to the grounding point rather than creating a daisy chain between pieces of equipment.

That should make a massive improvement, but to completely fix the issue, you'll need to do that same with all speaker drivers. Sometimes just grounding the frames or baskets isn't enough and it's necessary to also ground the magnets.

It that fails, then and only then consider changing equipment.

I’m going to re-iterate that changing your front end streamer is most likely to take away the edginess with your existing excellent DAC.

The aforementioned Grimm MU1 is my favourite for achieving this and it’s all in one box with the Roon "NUC" included in the tin (so you don’t even need to worry about finding a separate Roon Server).

It’s a stunning piece of kit.

Someone mentioned earlier that they replace their dCS stack with it.

One of the BEST for the money = Chord Qutest

And if you want to spend RIDICULOUS amounts of money = dcs Bartok

I really loved the Aqua audio la scala dac.  The roon player was a lumin, I don’t recall the model, their entry level.   I would describe the sq as sweet and relaxed, like a fine Italian dinner and wine pairing.  If I wasn’t closing in on retirement,  would swallow the cost.  Currently using sonore ultra rendu player and audio gd r7.  Combined 3700 dollars.  I call it my high quality knock off.