Our inventory arrived this week, and we've spent time comparing the Audeze LCD-X (open) and Audeze LCD-XC (closed) pairs on familiar material. These things have insane depth and detail for sure, and I would not say one is "better" in general but that each serves a particular purpose and does have its own delivery.
LCD-X are the open version, and are popular for mixing and mastering engineers to hear a ruler flat response and an unrestricted sort of openness rare in headphones. Listening to familiar mixes easily reveals compression and EQ choices, and individual elements are easy to focus on. Their flat response renders them an excellent tool for decision making for sure.
LCD-XC are the closed version, of course many are mixing and mastering with these as well. The first thing I notice is that this is what hi-fi is supposed to be like. Refined and detailed, but they are more musical and deliver a FEEL you expect from a high quality playback system. Somehow they are more familiar as a reference for me personally, like things gel as a complete picture and have a size to the sound I really enjoy.
We are excited to be your stocking, authorized Audeze dealer!