I am not disagreeing with anyone else’s experienced perspectives: HEK, Z1R, TH900, Aeolus all strike me as very reasonable recommendations. I would just add to that list the Auteur, whose biodynamic driver may offer a compelling contrast to that of the beryllium Utopia. If you can snag a 3F amplifier, you would be able to drive the Utopia/Auteur with equally impressive, top-shelf synergy. However, both can sound great out of many other setups. From the planar lineup, obviously you may consider Abyss, Susvara, or LCD-4, but I cannot speak from experience regarding these.