Brilliant sound. I'm loving the Soloist after 2 weeks. An amp must sound good to have my interest for that long, especially when there's no tubes to roll and nothing for me to fiddle. I can see why Lachlan of Passion For Sound love it so much. Pretty wide soundstage, clarity, details, texture and a fullness of sound that makes it sound rich and alive.
I get satisfying results with all of my headphones, LCD4, He1000se, He6se V2. Can't decide which one is the best pairing yet because they all sound good in their own way with the Soloist 3XP.
With dacs, I've used SMSL Do200 and NAD M51. I prefer the M51 for it's greater clarity though the Do200 is still good enough. Haven't been able to get my Yggdrasil yet because it's in my work accommodation and the Bifrost 2 is with my son.
Right now I have Odyssey my tube amp and Soloist connect to NAD M51 and I swap my LCD4 between the 2. While I still prefer Odyssey for it's sparkle and it's better dynamics, the Soloist is a surprise in getting close. This solid state amp sound really good, regardless of price.