Recently, there was an Audeze sale in my local shop so I could get these for 670€. I wanted to try them for a long time so I finally gave them a shot. I've been reading that they are less resolving but more neutral than LCD-2C, which is also what I would say about M1570 in comparison to LCD-2C, so I was hoping they could replace my M1570. Both LCD-GX and LCD-2 Classic are the latest 2021 versions with open-cell pads (the OG version had memory foam pads).
DISCLAIMER: I was writing it like I would talk to myself so when I say for example that headphone A is more comfortable than headphone B, I really mean that I personally find it more comfortable. Everything I say is just my impression I just didn't want to write "IMO" in every sentence.
Comfort
So far, the LCD-2C has the best ergonomics of any headphones I've ever tried. I always thought that LCDs with magnesium chassis were the same in this regard. So considering the GX is even lighter than 2C (457g vs 530g), I was expecting them to be an improvement to the already comfortable 2C. And for the most part, they are the same. The same headband, the same cable, and the same pads, but there is one thing that completely changes the way they feel. Different yokes.
Yokes on the GX have a more aggressive angle and more aggressive offset. That results in a lot tighter clamping and most importantly, most of that clamping is shifted in front of my ears. So whenever I pitch my head forward, the headphones will fall off. Even when I don't pitch my head, headphones will slowly slide forward until there is a gap behind my ears. It feels really awkward wearing them. Because of that aggressive angle, the rods connecting the yokes and the headband are now larger and I need to extend the headband more on the GX. Also, because of that angle, the headband doesn't hold its position but wants to open up all the time so I have to constantly close it to my size (which is 5 notches on the GX and 2 notches on the 2C as shown in the picture).
Also, the back side of the spring steel is sitting on my head because of the aggressive offset. And one last thing, the yokes are now also bigger because they're rounded so when I want to adjust the headphones on my head by grabbing the yokes, I can barely stretch my hands around them because they're so large. None of this was an issue on the 2C design. I can barely notice the weight difference but when it comes to ergonomics, it's really bad on the GX while on the 2C it's the best I've experienced so far. Overall, I find the GX a lot less comfortable.
more aggressive headband offset (tried to align them with cups)
more aggressive yoke angle (tried to align them with rods)
2C yoke angle when stretched around the same length
GX yoke angle when stretched around the same length
2C vs GX on the smallest headband position - GX would probably fit a cat when stretched
this is how the 2C headband sits on my head
this is how the GX headband sits on my head - btw I have a very average head
Practicality
GX is easier to drive (gets louder on the same volume) than 2C.
In terms of isolation, there's about as much of it as on the 2C, but I would say it feels a bit more closed in the higher frequencies and more open in the lower frequencies. Both are somewhere between open and semi-open in terms of total isolation.
What I don't like about 2C is an aggressive pneumatic effect, so it feels like wearing a closed-back. I can hear every movement, cable is microphonic because of it, and I can even hear my own breath and heartbeat which is pretty annoying. I don't get this issue on the GX, or at least not as much as on the 2C.
GX comes with an extra boom mic cable which retails for $180. The mic is pretty good. Sounds better than most integrated mics but not as good as the dedicated FOX mic I use. The boom mic cable is terminated with CTIA wiring where the mic and ground are inverted (common in China). But there is an adapter that fixes it to OMTP wiring where the ground is on the sleeve and the mic on the ring (common for the rest of the world - works with Apple dongle, phones, or any other amp). There is also a splitter if you want separate jacks for headphones and a mic. The splitter is wired for CTIA input so you should unplug the adapter first.
Sound
When compared to 2C, the GX has a more linear midrange which results in more cohesive imaging.
Unfortunately, it comes with a big cost of treble being very dull. It's not just slightly less detailed, it's a lot less detailed than both 2C and M1570. I would say it's competing with headphones like M1070 or Verum 1.
In terms of dynamics, it's still one of the more interesting features of LCD-GX but in comparison to other headphones for less money, it's really nothing special. M1570 or Verum 1 are more engaging than GX. I guess it's mostly because of that dull-sounding treble that makes everything sound compressed. It still has pretty good transience in the midrange and still sounds somewhat large, but it lacks that tactile feeling from the treble.
The soundstage feels a bit more intimate than 2C. I guess that could be also because 2C sounds generally more U-shaped so it feels more distant and more separated between left and right. I don't find 2C to be particularly spacious anyway. The soundstage is decent but nothing special. Comparable to something like Sundara.
The bass is similar but less noticeable and less textured on the GX.
Imaging, while being better than 2C, is still nothing special tbh. I tried them for competitive fps and while I didn't have spatial distortion like with 2C, I didn't find GX to be very competitive. Pretty average.
So all in all, LCD-GX are IMO very average-sounding headphones and that's the biggest issue considering how expensive they are. There isn't anything that makes them special. Anything interesting that's better than on other headphones. The best thing about them is that they don't sound offensive in any way. Their tuning is pretty casual and they're OK in every aspect. But there are cheaper headphones that are also OK...
Comparisons
LCD-2C is more detailed, more dynamic, more spacious, more neutral (general midrange to treble balance), and more comfortable, but also more U-shaped so they can get a bit too sharp at times and their upper midrange is a bit too dark and distant. That results in slightly unnatural imaging where you can't tell if something is in front or behind.
M1570 (lambskin pads) is more detailed, more dynamic, more neutral, and more comfortable (despite being very heavy at 689g), but the midrange is slightly less linear. Spatial qualities are similar.
Verum 1 is more neutral, more dynamic, more comfortable, and with better imaging, but the soundstage is slightly smaller. In terms of detail, they're fairly comparable.
M1070 (lambskin pads) is more neutral, but slightly less resolving, less dynamic, and there is a hole in the upper mids. Spatial qualities are similar. Trading blows with comfort.
Avantone Planar is slightly more detailed, significantly more spacious with a lot better imaging, but probably even darker and less comfortable than GX. Hard to compare the dynamics since Avantone is a bit rolled off in the sub-bass but more present in the mid-bass. I would say it's similar but different.
Thieaudio Phantom (without front foams) is significantly more spacious (probably even more than Avantone), and a lot more explosive, but less detailed and has a very weird tonality so it's brighter and more muffled at the same time, which results in inconsistent imaging.
HD660S is more neutral, more detailed, and with better imaging, but has a bit smaller soundstage and worse low-end.
HD660S2 is even more neutral, even more detailed, and with even better imaging, but still has a smaller soundstage. Low-end might be better on the 660S2. Feels more punchy for the very least.
Use case
I tried all kinds of genres of music, competitive shooters, ASMR, immersion, everything, and I really struggled to find anything that would sound impressive on the LCD-GX. It doesn't sound bad, but it didn't impress me at anything. The best experience I had with them was for immersion while watching some movies. But in the end, I still preferred M1570 or HD660S2 which are both cheaper.
Value
Even if there wasn't a boom mic making LCD-GX cheaper for $180. And even if it was on sale for 670€ like I bought them, I still don't think they're worth it. They are competing with headphones in the 200-400€ price range and they're more than twice as expensive...
Conclusion
As you can probably tell by now, I am very disappointed with the LCD-GX 2021. They aren't bad and I could enjoy them with certain content on lower volume. But I would expect this kind of experience for a lot less money.