some people said ZMF is the best closed headphone, you never know till you try it. I like my AP, but I'm trying out the ZMF OMNI whenever it coming. sorry dont know anything about IFI, but if they are using Bur Brown Chip it will have a warm sound sig, I dont know about you but I dont really like warmth sound signature. Theorem does have balance input.
8/24/15 at 8:58pm