The yincrow was recommended to me by Amar, who goes under the monikers of UncleRuckus and GhandisFist.
I bought one which included a microphone

The first and most important thing about earbuds is the fit, unlike the monks I own the foams on these didn't irritate my ears, neither did they feel rough. Despite apparently being the same shell these seemed to not cause any fatigue issues like the monk which would press into my ears. The included clip mean that I could quite easily go for a run in them without them falling out.
Overall the fit of these are really good and would stay in where beater devices would usually fall out due to poor ergonomics.

Moving onto the sound the two main strengths of these earbuds are the dynamics and bass extension.

Usually, an earbud falls apart in jazz or even modern pop because they don't have the extension to even have any form of midbass. The extension of these was enough to satisfy my requirements even in films. Aside from the extension, the bass performance itself was really good, it could accurately convey texture in drums to the point where you could determine between how hard the drum was struck, etc.. mainly because you could hear the difference between sustain and notes on kick drums. This same ability was present in cellos and double bass instruments in the Blade Runner 2049 soundtrack.

Moving onto the lower mids, the bass was well integrated with the lower mids, there is no real sense of bleed even in modern pop songs (like Havana) where the fundamentals and bass line were clearly separate and were resolved as such. The integration of the lower mids and dynamics leads to a very convincing sense of imaging (I will explain this in more detail later) since what you get in the lower mids is a good sense of spatial cues from the music. You can get a feel for the movements which make the sound happen. Obviously not to the extent of an hd800 or even hd580, but it is better than most other budget offerings. The timbre of the lower mids can be considered a bit wet, a lot like the HD6x0, where the decay is pretty liquid and it doesn't sound too fast, maybe even a bit slow for some.

The upper mids are in line with the mids and don't feel dipped or necessarily bumped, maybe slightly dipped compared to my hd580. A nice thing about this earbud is that the upper mid resolution is quite good for something at this price. it leads to the lower parts of the decay being in place because you have a sense of space.

The presence region of these earbuds presents some issues. There is a sense of congestion with these earbuds which comes across particularly in this region, it's more that the music feels stuffy as opposed to hazey like something with a 5k dip would cause. It's not really spiked either given that it definitely doesn't come across as nasal

The lower treble isn't dipped like the presence region seems to be and because of that cymbals have a good amount of sibilance as opposed to sounding damped like on the hd580, realistically there is a serviceable level of texture in this region compared to more expensive offerings.

the mid-treble and upper treble are dipped compared to flat FR speakers and headphones known for treble extension. These aren't the strengths of these earbuds and really anything at this price range. One thing I will mention is that the upper treble is considerably more present than a lot of iems simply because you have a greater sense of air.

The imaging of this earbud is really natural, I would consider it wider than the monks with a bit more depth using the full foams. what it does within this stage is really nice for an earbud, there isn't any significant rounding at the edges like most other earbuds, the decay seems well textures and expands into the stge, the congestion means that the seperation isn't quite as good but I wouldn't consider it smothered.

All in all it's my favourite cheap earbud which works well for running.

I have since sold these headphones after experiencing much better.

These headphones gave me a poor taste of high end audio and ruined my enthusiasm. I preferred the shp9500s to this and akg k712s/612s do what this attempts to do in a more agreeable package.

Let's start with the bass. The extension was quite limited and in fact all it was, was a mid bass bump. Instead of feeling the punch of a kickdrum or the reverberance of a bass guitar all you got was a warm blanket of enveloping distorting bass with no physicality. It wasn't controlled enough to feel like a good warm headphone.

The lower mids were sucked out, making sounds come across as distant, I'll come onto this in soundstage again, but it's a really poor quality. Listening more closely you notice a lot of the lower mids are smoothed over quite often the seperation between different notes and tones are merged together. Reducing fundamentals to simply a noise, it sounded quite disjointed and didn't feel real.

The upper mids are bumped on these which could easily five people the impression that it has got smooth Vocals with presence. However the presence region is inaccurate and ultimately the subtle dip spike causes a significant hazey quality to the sound.
The upper mids are where you get a sense for the space from the sound, where the lower mids make up the actual sound. In this case the unevenness leads to a hazey characteristic to the sound as if vocals are pushing through a film of air. It's the equivalent of trying to see something through a fog.
This leads into the lower treble where you have a spike in the sibilance region. A common misconception I have seen is that sibilance is solely from the headphone. It's inherent to a lot of vocals and instruments and up to a mastering. What a headphone does is change how forward the sibilance is and the qualities of the sibilance.
What the Fidelio x2s do is present them in a forward peaky way. S sounds and cymbals usually have a trailing decay, what the x2s do is push this forward and make it sound sharper than it is. This leads to a peircing quality.
Which ultimately makes them very fatiguing and isn't natural.

The treble isn't much better.
There is an inherent grain to the treble which comes across as constant background noise in almost every song. Even modern songs produced in something like 32bit with no artificial tape hiss have this grainy quality ackin to listening to old satellite tv speakers.
Ultimately the upper treble is quite lacking, there is a lack of air to the sound which would make a lot of the problems easier to live with.

One thing I notice this is praised about is soundstage.
It's reported as wide sounding.
My comment on this is that the dip in the midrange makes every sound originate further away than it does.
This doesn't do what headphones with good soundstage do and give you a varying sense of depth and width. Sounds either happen for right , far left or right in front of you and a bit forward.
Commenting on imaging and layering it's quite poor in this sense. The dt880600ohm,k712pro/612pro and hd6x0 outperform it quite significantly in this characteristic. You get a greater idea of how the sound decays in it's stage, how distant certain sounds are in any of those headphones.
The layering is also significantly worse with sounds often merging together and having similar qualities as opposed to what they should do and be different.

The overall tonal balance is quite poor and introduces significant colouration. This would be fine if the technical ability was at it's tier, but it isn't. The timbre is quite metallic across the board which indicates an unnatural quality of decay.

This review is in reference to it's price point it's not technically capable enough to be considered mid-fi by any stretch of the imagination. I'd even go as far as saying the dt990 is more technically capable with the same v shape tuning and arguably better comfort.
If you want a wide sounding Headphone with good imaging the a900x is probably a better option and more agreeable.

My main issue with these headphones is that they are priced to compete in a saturated market and don't compete with any of the options currently there.

I'm grateful for the people at audio sanctuary for letting me demo these headphones. I know a thanks is meaningless when my wallet should do the talking as they are a business.

I got to try these running off of the Dave and with the skull amp at audio sanctuary, alongside a lot of other totl headphones.
I feel like these compare most closely with the hd800 and to some extent the hek v1

I don't really have set music tastes. Quite recently drake, Charlotte Cardin and Amy Winehouse have been the artist's I have listened to the most.

Starting with comfort.
These are on the comfortable light side of the spectrum. Anyone who knows me from discord knows that I am really sensitive to weight and clamp, to the extent that I find the utopia uncomfortable after a few minutes. This doesn't feel as rigid as the hd800 on my head but clamps a bit more and sort of dissapears like my hd580 does.

Moving on to sound.
Bass
The bass levels aren't much higher than the hd800, if at all. It feels more punchier and more dynamic, and sometimes there is some minor bloat relative to the hd 800. It doesn't have the same level texture but matches a greater variety of genre, simply by having a greater sense of impact. This isn't a warm can by any means and at times can feelanaemic due to the lack of depth. Anyone who had visited a concert or been arounddrummers should know how a kickdrumfeels, while in recordings some mastering is at play, neither truely convey the impact of something like that.

The mids are where the ad5000x really shine. I'm particularly sensitive to mid tone so it won't come as a surprise that the stuffiness of the hd800 really coloured the tone. Whilethe texture came through on it, it sounded really stuffy, as if there was no presence. Thead5000x isn't really weebfi by any means.The upper mids relative to lower mids ismore balanced, I'd go as far as saying the upper mids aren't as bumped in fr as the er4sr Charlotte Cardin's main girl (stripped) and Amy Winehouse's back to black both highlight the raw meatiness of the artist's vocals without getting shouty. It conveys this in a way which doesn't sound smoothed over in a very Romantic sweet way.
While the upper mids can seem slightly emphasised compared to my hd580 it's so slight that I had to keep switching between them to notice the extra presence. The extra texture made it quite hard to discernbecause it didn't have the same overall relaxed balance as the 580. The mid timbreand tone between the two are different, butit's quite a subtle difference, just notsomething you have to work on to figure out. Pianos and accoustic guitars came through really well with an accurate tone. You had a sense of the individual strums and the air being pushed, overall there was a lot of resolution in terms of texture being conveyed. Aggressive pianos conveyed that sense of aggression with no attempt to hide the nastier parts of the sound. It allows asignificant amount of character to be addedto each instrument, as you would. Brass instruments have the raspiness that you get(why I never liked the trumpet), stringsresonate in the space and have the edge that they do when pushed. These doesn't smooth over detail, which makes it quite unforgiving with poorly mastered songs and anything using instruments which are usedaggressively which might not play into otherstastes. It does add character to instruments,which for people like me, makes me more involved in the sound.

The lower treble provides a good amount ofair which is similar to that of the hd800. It doesn't feel closed in despite it's smaller stage and because of that sounds seem to exist within a space and decay into the space. The issue with the hd800 is that the airhighlights the stuffy mids by isolating them in space.
In this particular instance I don't get it, but the lower treble of either doesn't bother me, like the x2 did, or the hs1551. Both conveysome form of sibilance in sibilant songs, but the air allows it to dissipate. The nature of the sibilance in both is quite different. The hd800 seems more subdued and dulled as opposed to veiled. The adx5000 has more sustain and more body making it a tiny bit more prominent, but the timbre of it is different. Which sibilance is natural is beyond me, I prefer the adx5000 here due to preference, I can't say which is technically better in this regard, only that they portray it differently. Neither has painful sibilancewhich bleeds into the rest of the sound, it'sjust there.
In terms of mid treble and it's integrationwith lower treble, the headphone works really well.
The cymbals have a TISHHhhhh sound as oppose to the TUSHH of the clear or the TISSsss of the he100v1. Treble is conveyed accurately with a good timbre. One thing tonote is that these headphones will spit glare at you when dealing with glarey treble in the mix because of this, they're definitely unforgiving
I personally believe that technically superior unforgiving headphones still sound betterthan low quality ones on a poorly mastered songs, other people will focus on this more.
I should mention most of my listening is focused around the mids, I'm not a treble head, so the treble glare isn't particularlyannoying to me.
Coming back to the mid treble I can't help but feel it is ever so slightly veiled in comparison to the hd800, despite theresolution and accuracy. The treble of neither bothers me too much, so the veil hasn't meant that I think the glare is worse than it is, since both of these headphones do that.

Being an idiot I mentioned air in the lower treble part, when it's upper treble. I'm not bothered to redo the structure of this so I'llcarry on. Both are quite airy headphones. But the hd800 is superior in this sense. Itconveys a greater sense of air which makes sounds seem more in place than theadx5000 at times. It's quite a stark difference. Both are more airy than the focals and to some extent the he1000v1 can sit in between the two.

Presentation is slightly different on the two. The adx5000 had more body to the sound, it was quite noticeable. However it was far from the utopias which is the king ofheadphones in this regard. It maybe had more body than the he1000v1 but don't quote me on that. Nevertheless, it is still thin, lacks impact and dynamics.

In terms of staging they are quite different.The adx5000 has a smaller soundstage and is therefore quite closer. I believe it's equal in width to the hekv1. In addition to the body itcreates a more intimate sound. The level of seperation and imaging created a good stage in which instruments and vocals came fromdifferent places with a good amount of depth to seem convincing. The sounds didn't seemrounded at the source and neither did they seem to dissipate all over the stage andsmother it. The good level of clarity added to this stage. But these stages were quite close and at times sounds could come 70° off from in front of you. It's disorientating and attimes annoying.

This doesn't do the same thing the hd800 does with staging. The closest thing to thehd800 was the kuru da, but I believe that is a technically worse, thinner and a less enjoyable headphone. While I initially thought there was a limit on how close the sounds on the hd800 are from you. It wasquite clear that this is a result of the staging properties in general. It is an out of yourhead kind of sound, the stage is in front ofyou, not a metre a way but closer to what you get at a performance. On that stage there is a great amount of depth, it expandsfar and not at weird extremities to you. Because of this the superior imaging andseperation, alongside the air provides the most accurate sense of stage you could probably get in a headphone. It's quite unique and hard to describe. To some it can feel diffuse (kind of me), but for people who enjoy this, the staging capacity of this headphone is unmatched and the adx5000 doesn't touch this whatsoever. It's staging is more typical to a headphone.

In conclusion I prefer the adx5000, I like the extra body and more accurate mid tone, as those are my preferences. I feel as though this tuning allows it to resolve slightly betterthan the hd800 by conveying a greater sense of texture.
The hd800 on the other hand has it's unique staging akin to speakers. It's the thickest sounding of this kind of headphone and I feel as though the tuning aids it's sense of staging.
Both are analytical and unforgiving headphones with accurate treble and a thin sound, but that's as far as the similarities go.

Sorry for the wall of text.