I touched on this a few days ago with the below comment.
Of course this isn’t to a tee. Just a humorous way to sort of sum it up. They’re both easy listens for me. The EST shines more in the mix on the Moonlight. There’s a touch of airiness to the mix. Hence why I made the comment about it being more euphoric. I’m able to pull out the amazing details in songs easier while it not being analytical or dry in overall tuning.
For me UP is all warmth and personal. The soundstage is small and the vocals closer. That’s part of how I define intimacy. Like the band is doing a personal show in small room under candle light for my wife and I at a nice restaurant. The night is all about her and I don’t want the music or my mind to take away from it yet enhance it. As if it’s there but not meant to distract or guide the night.
Moonlight has warmth but, leans slightly towards being neutral. Soundstage is wider, imaging is fantastic, vocals are cooler and details and energy pull through better. As if my wife and I were in an open field on a nice cool yet warm early spring night. Sitting on a blanket enjoying a glass of wine and a fine cheese. The night is still about her but, the music pulls you two in more. Suddenly you find the music guiding the night more.
Well sorry for my ramblings. I realize it’s probably an awkward way to compare them. Just been my approach lately. See what feelings an IEM/Bud brings forward with a song or how I’d imagine the presentation/tuning fit into a scenario of my life. Even something like the ASG 2.5 had a fun nostalgia that brought me back to my younger club going days. Just didn’t find it getting much use for its price and let it go. Still looking for cheaper replacement for it.