It sounds strange, but there is a special synergy between a Headroom amp and the Utopia. It sounds really excellent, with strong,controlled bass and tons of detail and silky vocals and mids, and even some fine layering in staging.
I have a Headroom Max with it and I just love the sound. (It also is doing a very nice job with my LCD4.)
Try to seek one out.
Here's one for $800 I just found by googling; I would snap it up ($800 is like spare change jangling around in your pocket in this crazy hobby):
https://www.amazon.com/HeadRoom-Desktop-Balanced-Headphone-Amplifier/dp/B013Z8P6CU
(It's not a Max, but it's in the same close family; designed by Tyll.)
Original review of the Max by the late Wes Phillips (who had a great ear for things):
https://www.stereophile.com/headphones/261/index.html