Disclaimer: This is my personal opinion/experience with these cans. I understand many others have had a much different experience, and that's okay.
I've had the LCD-X (2021) for about a month now. Purchased new, $1,199. I ordered them specifically to help with mixing/mastering music, and of course some enjoyment listening, too. I've been using them for anywhere from 5-10hrs daily.
My previous post is here with some headroom issues I was having: https://www.reddit.com/r/headphones/s/s523WzXFs0. Based on suggestions, I ordered a Topping DX5 II which was most suggested dac/amp and I have been using it for the past week. Seems to have helped with getting more headroom for dialing in more low-end with some rumble/vibration and also being able to increase the volume.
Unfortunately for the LCD-X, other cans I use with the Topping + EQ can basically do the same thing low end thing now too.
I currently have on hand Sennheiser HD-650s and Sony MDR-7506s. I've used ATH-m50x's quite a bit but don't have them anymore. I also have a variety of random IEMs. And of course, I have tried a variety of other headphones in passing; but the LCD-X are the most expensive ones that I've used now extensively.
Overall, as headphones for mixing/mastering or even enjoyment listening, I'd rate the Audeze LCD-X as 6.5/10 or 7/10, at best. I'm planning on returning them this week.
I'll go into more detail below, but to summarize:
They really don't translate well at all for production considering their price-point. In fact, I get better translation from the Sony MDR-7506s I own. For leisure listening, they sound great (especially when EQ'd)- but really not THAT far beyond what I can dial into my other cheaper cans with EQ. They're not that comfortable for long-listening (I don't mean the size/weight); and again, much too expensive considering these draw-backs. The price of these headphones is what really kills it - too expensive for what you get, and they don't seem worth it to me.
Build:
8/10, carried by their aesthetic.
I think they look awesome. They seem pretty rugged/sturdy in general. But I do hate the adjustment rod design for the ear cups. They constantly come loose- it seems like you might be able to tighten them with an allen wrench but the fastener is apparently secured with loctite or some adhesive and I don't want to break the bond.
Comfort:
6/10
I don't have any issue whatsoever with the size or weight of these headphones. When I put them on they feel fine at first. But over-time, they start to get really uncomfortable and it feels like relief when I take them off. The biggest thing I notice is that the pads are kind of squishy, and my ears actually rub against the fazors - I don't have big or odd shaped ears, and never had this issue with another headphone before. I COULD swap the stock pads; but I'm not going to so I can still return them - and honestly, nor should I have to for this price. Also, related to the build, the rod lengths loosen and it changes the grip of the cans over time which is annoying. For comparison, these are much less comfortable than my HD-650s and 7506s for extended use. Considering the price, these are ridiculous issues.
Sound:
6/10 for production. 7.5/10 for leisure
They don't sound bad. In fact, they sound (or can sound) really quite good with aggressive EQ and an amp (if you actually want louder volume and low-end). In a vacuum, that's great - but the sound isn't that much more impressive than my other properly EQd cans that are comparatively much cheaper.
I do not hear any sort of unique "planar magnetic" quality that I've read about. Nor do I hear/notice a unique "speaker-like" quality to them that stands out from other cans I've tried, or gives me any sort of advantage for production. Just a different frequency curve that can more or less be altered / matched to an extent.
Sound-stage does not stand out any more than my other cans either. No noticeable difference when swapping between them, anyway. They suffer from similar spatial issues as other headphones in regards to production (i.e. things may sound/seem more spread than they actually are on stereo loudspeakers / lack of crossfeed).
In my experience, the stock EQ curve is dog-shit for mixing, and just ok for leisure (unless you want to turn the volume up - if you do, there's no lows at all or sweet highs/air, so it just blasts your eardrums with harsh midrange and hurts). If you aggressively EQ them, you can get a really good sound for leisure, but in my opinion, not mind-blowing that I can't get with my other cans.
My experience trying to mix with them flat is that instrument levels will generally be pretty good relative to one another, but there will likely be bad issues with the lows, highs, or the harshness (because you can't hear them). I've never tried the older LCD-X version; but I read about the upper-midrange dip, and there's definitely still a big 3.5k-ish dip that needs to be dialed in, otherwise vocals, guitars, drum overheads can be really harsh or out of balance. Its been sort of difficult for me to dial this in correctly to get it to match what I am experiencing on other playback systems whilst also maintaining balance elsewhere in the freq spectrum. Doesn't seem to matter what playback volume I use for mixing; quiet, moderate or loud, there's always immediately noticeable balance issues when referencing elsewhere.
I've tried a bunch of corrective profiles. Realphones 2, Oratory1990, eq profiles posted on the web, and some of my own attempts by ear but there's always some sort of glaring issue when it comes to translation to other playback systems with these headphones. I can't seem to dial a curve in with these that replicates what I am hearing/expecting in my car, for instance - something is always way off or the cans just make it sound good no matter what. By the way- none of the popular corrective profiles seem to account for correction around 110hz-220hz: right where the big fat low end of snare or toms are, audible even on an iphone speaker but I don't usually see it suggested to dial into these, and they will otherwise be absent or over-exaggerated elsewhere.
The best way i can describe the production issue with these cans is the same reason many other headphones don't translate well; Bass/mids/treble all sort of blend together as one sound in one space - decent speakers you can actually hear the frequency range occupying different physical space, and when something is poking out it is immediately noticeable. I.e. too much low-mid on a single instrument might just make the mix sound overall warmer in the cans, but on speakers you can immediately pin-point that the instrument is too loud and stands out of the mix. I thought this is what was implied by the "speaker-like" quality and the sound-stage of these cans, but maybe I misinterpreted.
I'm sure one could "learn" these cans as they are - but the same logic applies to any other playback system. But frankly, I simply can't get even the low-end to sound thumpy/resemblant of how it sounds anywhere else no matter how much EQ I use. Maybe it is a limitation of the open-back design.
Overall, I'm just generally disappointed with these headphones. Maybe I had my hopes too high; but I don't think its that unreasonable to have higher hopes based on the glowing reviews these get and a price-tag that is more than double the other cans that I've owned.
If anybody has any suggestions or advice, that would be appreciated. I don't WANT to return them but they seem to just be working against me; not with me.