I have got my LCD-MX4, and have been listening to it for a few hours now (only 6 hours or less), and so far, I am experiencing a sort of "good news"/"not so good news" kind of result.
Good news : I like the headphone a lot, aesthetically, build-wise, and most importantly of all, SQ-wise. Oh, and they are brand new, not B-stock, and that is great.
Not so good news : I have been comparing them with my LCD-X playing both on my nearfield rig, and they seem to sound too much alike to my ears, to the point where, I am already thinking of letting one of them go. From what I can tell, the MX4 seems to be edging the X slightly in the clarity of the mids, in imaging, and overall refinement. However, the bass of the X seems to hit slightly harder than the MX4, very slightly. The differences are subtle, and not pronounced enough (at this point) to create a big enough delta of preference between the two cans to my ears, and that is precisely the issue.
The rig is:
Metrum Acoustics Ambre/Roon ==>> Metrum Acoustics Onyx ==>> Cavalli/Monolith Liquid Platinum (with "Holy Grail" Reflektor tubes)...I am also using a Norne Audio Silvergarde S aftermarket cable with both cans, and playing them in balanced mode...
I am wondering whether the similarity has something to do with the MX4 being too new and not "broken" in or "burnt" in enough, or whether there is something in my chain of components, which is blurring or erasing the differences between these two cans... Strangely, it was relatively easier for me to tell the difference between the sound of my LCDi4, when it arrived, and the LCD-X... I am very fond of my LCD-X, for sonic, as well as sentimental reasons (it was my first Audeze headphone), but I knew within the first 5 minutes of using the LCDi4, that I would prefer many SQ aspects of the latter over those of the former (notably, soundstagive, instrument separation, air, and a sense of overall refinement), at least for some types of music...
Again I like how the MX4 sounds, and would easily consider it to be a keeper under normal circumstances. What I do not like is the redundancy of having two Audeze cans sounding so seemingly alike on my rigs. When I get the chance, I am going to try both of them on my Yggdrasil2 ==>> Violectric V281 rig too, and see whether those will produce more marked differences between the two cans. If not, then I might have to consider selling one of them (maybe the MX4) or trading it up for another pair of cans that would provide me with a more different flavor (A used LCD-4, or Susvara, or something from the ZMF range of new releases, which I have only read about so far, but never experienced)...
The sad thing is I have the MX4 on my head now, listening to Nik Bartsch & his Ronin's Randori album, and I am absolutely digging the way the MX4 is resolving and presenting the entire sound-field. The way it is positioning each instrument in its own place, within that field, --and the coherence of the whole ...Quiet a thing of beauty... This is good! Maybe, it is my own head that needs some "burn-in" time with the MX4.... Maybe I just need a little more time to get used to these new cans in order to really discern and pick out its subtle SQ differences, before I can get to appreciate what really makes it different from the X? I do not really know.
If anyone has any insights into this rather odd situation, kindly share your thoughts.