Rögnir is a very impressive HP. I had the VO before and I wasn't also a huge fan of its signature -I preferred Stellia over VO. Then I heard the D9200 and chose D9200 over Stellia, especially because of the clarity it has. Now, I heard the Rögnir and it is the next level of everything.
First thing that really surprised me is the build. I saw a wood containing HP and I immediately thought of Audeze, ZMF etc., but then I took it in my hand and it is light as a feather! Wow! then I put it on my ears and I have to says, one of the best, if not the best, fits I have ever come across. Fantastic comfort! First time I am a having this type of headband design and it is very well made and designed. So good!
It is the next level in every way: Clarity, comfort, instrument separation, stage, depth, tuning, detail. D9200 has a harder hitting bass but Rögnir is more detailed and clearer. Stage width and depth on Rögnir is better, but that makes in some recording mids to be slightly further away, but I prefer that - I don't like it to be right in my ear. It has a neutral sound with an extended and slightly more energetic treble tuning (but not as pronounced as D9200).
Rögnir can easily become the "the" HP to cover your both open and closed back needs. It is the best closed back, and one of the best HPs I have ever heard.