Received the LCD-X earlier today. Some early impressions:
-First off, this is not Audeze's take on a neutral headphone, this is Audeze's take on a u-shaped headphone. Tonal response similar to the HE-400 but less treble.
-Soundstage is ridiculously deep with good imaging capabilities, not too wide.
-Same smooth goodness and lack of grain you're used to with Audeze products
-Treble isn't as extended as it could be, slight spike at around 8-9khz that can come off as hard.