I think the 380s are another solid closed-back, I would suggest either it or the HM5 for anyone looking for a neutral closed back, although it's been a long time since I've heard either the HM5 or HD 380. I am in the market for a closed headphone as I am satisfied in terms of open-backs with the K612. I have like 4 or 5 closed-backs I am debating between, I need to sell my MA900 first and I want to try my vintage closed backs I left at home again with tubes to see how it sounds on them before taking the plunge with another headphone. I want to find a good closed back I would be satisfied with for a long time so I can be free of this expensive hobby until I can afford to put more money into audio.
I saw one of your pics ... you have a shimian .... good choice enjoy all the pixels :D