I realize this is eighteen months late, but I can comment about the LCD-X and the Atticus.
I purchased a pair of Atticus to add a head phone with more authoritative bass than my HifiMAN HE-500. I like the Atticus for exactly that. Bass rumbles a bit more and has noticeably more slam than the planar head phones do. That does not come at the expense of the mids or highs, which are still smooth and easy to listen to. That said, the Atticus may not be the last word in treble extension, but to me they are satisfying. I don't notice sound staging in head phones that much. The Atticus; however, has a more 3D presentation than my HE-500 and more volume than the LCD-X I am currently trying. The Atticus are definitely warm, a plus for me. I like lush sounding gear.
The LCD-X are a different breed altogether. A friend loaned me his LCD-X. What you've heard is true: the first thing you notice is bass. It goes quite deep and at high volume actually hits hard. Bass quantity is actually dependent on volume level with the LCD-X more than the other head phones I've tried. They are quite extended in the treble, but I'd expect that. What is a surprise is how immediate they are. Notes start instantaneously, which is fun. Unfortunately, the price of the blazing fast start-stop is a lack of bloom. I noticed this with vibraphones (which I've been listening to frequently these days). The LCD-X, like the Auteur I had a few weeks ago, does an amazing job of highlighting the leading edge of each mallet strike. But where my HE-500 then allow each note to swell and fill the listening space with lush reverberating sound, the LCD-X moves on to the next note. This characteristic is a strength for fast music and music with lots of transient information: plucked guitar, pizzicato strings, bells, etc. But for more mellow fare, I feel like some of the development is missing. To me the LCD-X is a "between-the-ears" experience. Within that small space, there are localization cues, but the soundstage is not expansive. Another surprise for me is how much energy the LCD-X bring forth. With their bass capability it's hard not to turn them up louder than you usually do. I find myself physically tired after listening to them. Unwinding before bed is not something the LCD-X is suited for.
I have not heard the LCD-2, but I think the bass freak inside you would be satisfied with the LCD-X.
