Hello,
I used to own the 400xi for almost 2 years. This is a pretty neutral and analytic piece, but I didn't realized at first it was really lifeless regarding music.
I started asking me questions when I realised I spent less and less time listening music. I was bored.
My system was Rega Satur + 400xi + Totem Forest
When I changed the Krell for the Plinius 9200 it was like a complete new system. Same transparency but so much more involving, with more dynamic, better timbers, instruments took their body back.
Since then I can stop listening and enjoying music again. I added the Hovland Radia which gave me more impact and dynamic. That's all about music !
I listen essentially Jazz and World music, And I prefer subtelty over strengh even if my description tells more about strengh.
Sorry for my approximative english. Good luck
Fabien