ThieAudio - Monarch MKIV

For me it’s a mix of the feel of the build quality along with generally higher resolution and better separation of instruments as you go up in price (to a point). Other than that tuning is largely the difference and you could easily prefer a $300 IEM with your tuning style to a $1000 one with a different signature. I just got the s12 ultra used for $120 and compared it to my $1000 monarch mk4 and honestly it’s tough to justify keeping the monarch. The resolution and separation on the s12 are pretty impressive, the bass hits more to my liking as well… then I compared to my old apple ear buds and there is a clear difference in resolution even though to me the apple buds still sound pretty dang good. Other ppl will have better explanations I’m sure and it’s debatable what resolution means to people in this hobby. Either way In today’s market, $50-300 can get you some incredible sounding IEMs

can't judge about others. got the monarch mkiv only as 2025 release and enjoying them quite a bit. my only comparison is the dunus sa6mk2.

Never tried the mk3 but own the 4 and agree with most of your impressions. Particularly that they are much more unforgiving on poor recordings than my Dunus SA6MK2. I can’t listen to some Bob Marley tracks unless they are remastered with them, even though all my files are flac. Also agree that the bass is a tad heavy, and so is the high trebles to my ears. Am going to spend some time eqing them to my taste over the weekend

Purchased the Monarch mk4 last week, looking for a warm upgrade from my Dunu SA6mk2 for easy and musical listening with a bass boost compared to the Dunus. After burning them in for a few hours and paired to my iBasso Dx180 I feel like it's a miss. Pros: - the extra bass rumble is there, particularly in the sub bass department - very revealing - large soundstage - goes higher in the trebles - Nice for bass heavy music like afrobeat or hip hop Cons (to my needs and taste): - the soundstage is larger but more forward. so not a laid back listening - the voice timbres can get fatiguing. overall i prefer the male voices on the Dunus. - i find them overall less musical (and more revealing) in their presentation than the Dunus - they are more unforgiving on old tracks with poor recording in example some Bob Marley tracks sound horrible with it - they tend to get fatiguing soundwise to my sensitive ears So yes it has its qualities and I can see a crowd for it. But it's quite a big miss for me, i get an energetic, in your face, revealing iem while i was looking for something musical, laid back, but with extra sub-bass vs the Dunus. I'll give them another try when my new dap (onix xm5) arrives but have little hopes, will probably end up flipping them (in Europe if someone interested). Based on this experience, what would you recommend i go for to reach my aim: laid back, warm and musical listening with just enough extra details to make it worth vs bluetooth earbuds, and good enough bass rumble - not necessarily basshead as I listen to lots of jazz also-? Price not the top consideration, anything from 200 to 1500 usd is fine. Just looking for the one and only second iem that will complement my Dunus and rest my game.

yes these will probably end up in my rotation sometime as I'm reading such good about them. my concern for now is that they don't seem to have the added sub-bass I'm looking for vs the sa6. for the story was hesitant between the Volume S and the SA6 when i made my first iem purchase. went with the Dunus.

Probably one of the Thieaudio Monarchs. Either the MK2 or the MK4 while in standard mode.

Tips are extremely different on IEMs. I have Monarch Mk4 right now, one tip even with the bass tuning switch can make it far more open, lower end more detailed than more boom, then I swap to another, stage shrinks a bit, but its a bass head set suddenly. Part of beauty of IEMs is tip rolling. Not just comfort but the entire sound can change. You can to some extend do this with headphones, but not on the same scale.

If you can afford the MKIV, it is truly amazing, metal shell, tuning switches that make it a very close MKII tuning or a MK3-LTD. If not that I would say the tea pro or odyssey 2 for less bass, I personally regret and truly hated the top pro, I loved the vocals but there was in fact some weird warm. And the 3D shell IMHO was a downgrade from resin builds, felt like I could crush it. Could be a pro for you if you really hate the weight of IEMs. The RSV MKII looks nice and graphs amazing but for a 5BA set, 700$ seems a little much tbh. Dawn X looks great, but the only thing to consider is if you care about bass it definitely is more balanced or reference tuning, so is the MKIV but has 2 options if you ever want to tone it up or down. PLUS, it doesn’t have a lip on the nozzle so tips could get stuck in your ear every now and then. I'll end by saying that the MKIV is basically a better top pro, with rumble off it graphs almost identical, and has ESTs. Top pro has a very noticable mid bass scoop and thats what most reviewers dislike when they say it doesnt have enough bass. If you want something more affordable than the MKIV while being like the top pro I would look at the NiceHCK Rockies, for the same 500$ you get more for your money (BUT doesn't have a lot of bass, tea pro would be the better alternative).

So that’s the thing. You CAN have great quality bass by using good drivers, while minimizing quantity. But with modern woofer improvements, manufacturers naturally went with MORE bass. Easy way to test this: take a good quality bass iem (i’m testing with Monarch MKIV) and just EQ the bass down by 5dB. You still get really nice bass texture, but cleaner tone

Disclaimer: I'm not a reviewer. I'm just an audio engineer and a guy that loves music. These are my impressions. If I left anything out, please feel free to ask. I've had several days to compare both of these IEMs. Originally, I'd bought just the MkIII, but after several days with it I contacted a rep at Bloom Audio and asked him for some advice. I asked if there were something he could recommend with less mid bass and a more open sound. Without hesitation, he recommended I try the Monarch MkIV. I asked about the Prestige LTD and Dunu Glacier, but he insisted again that I try the MkIV for what I'm after. I listened to various genres over the last several days, mainly metal, rock, classic rock, and EDM. I'm using an Astell & Kern HC4 plugged into the USB C port of my iPhone 16 Pro Max. I tested both cables on both IEMs, and used both the 3.5mm and 4.4mm tips. Cable and accessories- Cables: Both sets come with a nice modular cable. The MkIII comes with 2.5mm balanced, 3.5mm unbalanced, and 4.4mm balanced tips. The MkIV comes with only the 3.5mm unbalanced, and the 4.4mm balanced. The MkIV's cable seems a bit higher end, but is a little too bulky and heavy for me compared to the MkIII. I prefer the MkIII's cable here simply for the comfort. Tips: The MkIII comes with a set of standard silicone tips and a set of foam tips. The MkIV comes with a standard bore silicone, narrow bore silicone, and foam tips. I've tried swapping in Azla SednaEarFit ASMR, TRI Clarion, and Spinfit W1 tips. To my surprise I liked the stock silicones the best, and the standard bore silicone over the narrow on the MkIV. The stock silicone tips on the MkIV do seem to be of higher quality than the stock ones on the MkIII. Case: The MkIII wins hands down here with its semi hard zip up case. The felt covered cardboard puck of the MkIV is simply trash. My package was brand new in the plastic and the sides of the puck were already starting to collapse when I took it out of the box. I've already ordered a replacement case on Amazon. Sound Impressions- Bass: This is one of the main noticeable differences between the two IEMs. While the MkIV has less upper mid bass energy than the MkIII (a welcome change), both IEMs are what I would consider bass heavy in their sound. If I could reduce it just a little more on the MkIV I would prefer it. The bass on both sets is big and punchy, if a little undefined at times, and not as snappy as I'd like, but overall of nice quality. Worth noting that the bass quality is better at moderate volumes than the lower volumes I tend to listen to. I think if anything, these IEMs tend to highlight flaws in mixes and masters. Tracks with a well defined and sculpted low end tend to shine here, while sloppy and bloated low ended tracks are exaggerated. The main thing that turned me off from the MkIII is its mid bass that does quite often tend to dominate the sound of whatever I'm listening to. The MkIV is much more controlled here, though you do have the "rumble" switch that will give you a 3dB lift in the mid and sub bass area, giving you a somewhat more controlled emulation of the MkIII's bass if that's what you're after. It can definitely make the right track bigger and more engaging for certain genres. Mid Range: This is the Monarch's wheelhouse. There's a saying in the pro audio world that "the magic is in the midrange", and I strongly agree. Without great detail in this frequency range, you're really missing out on a lot of crucial information about the song. Both sets have a natural and detailed mid range here, with nothing to objectively complain about. The MkIII is elevated, as you can see in the FR graph, at around the 4-6khz area. And while this does give the MkIII slightly more detail with vocals, drum attack, and guitars, it can also be the source of fatigue. And in my case, irritating my tinnitus. Because of this, I found I tended to listen to the MkIII at a much quieter level than I'd like after about 15 minutes, while on the MkIV I can listen to moderate levels for much longer without fatigue or amplifying my tinnitus. Upper Treble and Air: I was a little surprised at how much more open the MkIV's sounded compared to the MkIII when looking at the FR graph (last pic in my post). The slight lift at 10k and the big spike around 15k seems to contribute a lot to the general sense of space and air in the MkIV. The MkIII sounds a little rolled off in the upper treble, the MkIV sounds open, airy, and gives you a better sense of space. These are just different flavors, and I can see some preferring the warmer top end of the MkIII. It's reminiscent of listening to a recording on older analog tape to me. The upper frequencies are slightly subdued, but all of the information is still there. The MkIII shines on recordings like David Bowie's Ziggy Stardust and the Spiders from Mars. It sounds accurate to the recording and to the era. The MkIV makes the same album sound like it was remastered for more air, cleaner bass, and more separation. This is where a case could be made for owning both sets of IEMs. Comfort and Fit: This is another area that surprised me. I find the MkIV to fit perfectly in my ear, and for long periods of time. I was expecting a heavier and clunkier feeling IEM because of its slightly larger size and the fact that it's made from aluminum. They must have fine tuned some of the contours because I don't have to twist or push the MkIV to sit in my ear like I do with the MkIII. It also feels lighter, even though I saw a review where they actually weighed both sets and the MkIV is the slightly heavier of the two. The large nozzle of the MkIII also started to hurt my left ear canal after about an hour, whereas I haven't had that issue with the MkIV yet. In the included pics I show the fit of the MkIV, which sits very comfortably in the ear, but does protrude just a little more than the MkIII. Summary: I guess it's obvious by now that I prefer the Mk IV for my own tastes, and will be sending the MkIII back to Bloom tomorrow. I didn't see many comparisons out there when I was originally searching for a replacement for the MkIII, so I'm hoping this review can help some people that are also considering these two great IEMs. Thanks for reading.

Small update, went a size down on the Spinfit W1 tips and I'm really happy with how those sound compared to stock. More open, more mid clarity. Slightly subdued bass, so the rumble switch on the MkIV actually works great here.

the monarch mkiv can sound jarring if you’re coming from a warmer iem (i have the sa6 mk2 and it’s hard for me to categorize. sometimes it sounds warm, sometimes it sounds open and bright—not sure how you hear it). but, since it’s already in your hands, i’d give it some more time. just today, i put mine on and found them to be warmer than i remembered. sometimes it just depends on what you heard last, how tired you are, etc. otherwise, maybe the mega5est. it’s more vocal forward than the sa6 mk2 and more conventionally tuned, so it would complement your sa6 by giving you something that sounds a little more proper while being more laid back and natural than the monarch mkiv. you also don’t give up too much in terms of technicalities. coming from the monarch mkiv, the bass will definitely sound less defined, but i think it fits the overall sound signature well. some people call the mega5est boring, but musicality is subjective and hard to define. i’m a neutral head and the mega5est has a touch more warmth and bass than what i consider neutral, so in that sense, it’s musical to me. if you want to be risk-averse, the ziigaat arcanis has pretty much replaced the sa6 mk2 in my rotation. it’s what i expected the sa6 mk2 to sound like (and what i wanted the mega5est to sound like). a bit more sub bass and bit more satisfying bass overall. i find the upper mids and vocals of the sa6 mk2 to be too recessed and the arcanis addresses this by bringing them forward just a smidge (but not as much as the mega5est). vocals have a vibrant quality to them that you might consider musical. and there is just enough treble extension to give it air and sparkles. it doesn’t come across as technical as the sa6 mk2, but all of the details are still there. it’s unique and i actually like it more than the mega5est, but that comes down to how it fits in my collection penon/isn has been recommended a lot. i can vouch for the ebc80. its warm, has phenomenal sound stage, and is super fun. it isn’t fatiguing at all to me, but it doesn’t really fall under the category of laid back. their other iems might for the bill, though. these recommendations i think would be an “upgrade” to the sa6 mk2. however, my philosophy is that for a laid back sound, you don’t need to spend a lot of money. so personally, my warm, laid back iem is the ziigaat arcadia. it’s warm, punchy, has just enough treble, and with the right tips, can sound just as well-executed and beautiful as anything in the $200-$250 range. i prefer it to my penon serial and canon 2 for this purpose. i’ve also been going to the odyssey 2 a lot for a laid back listen, though it is not as warm. the punch audio martilo is also a good choice if you think you can tolerate a lot of sub bass. it sounds mostly normal and conventional, which, like the mega5est, could complement the sa6 mk2 well. when there isn’t a lot of sub bass in a song, it doesn’t sound like a bass head iem. but when there is, the bass sounds like you have a sealed subwoofer in front of your face.

I love it and I also have monarch 4 but still love it especially for older harsher music

The monarch mk 4 sounds deliciously balanced on all source material

My Monarch 4s with bass boost are pretty great for metal but I still find the explorer better suited for harsher older stuff

Also audio engineer and agree with most your thoughts. It takes me a while to learn new monitoring but I feel the mk4 is very intuitive. It seems to combine what I like about my genelec, lcdx, and aryas. And its just plain fun to listen to. A true marvel in my opinion that would be hard to beat.

Try before you buy! Demoed it yesterday and big guy did not want to fit. I can get a seal but it's not for me.

https://preview.redd.it/6nhpgy886mnf1.jpeg?width=3000&format=pjpg&auto=webp&s=0b14ec1d717dc99b4c7a4ed7b4b7b2419cb3d528 They're just too good! Monarch mk4

I had a Tea Pro, now own a Monarch mk4. I would say its slight better, maybe around 10% better if that.

i was researching for my endgame stuff and this is what i think monarch mk4 ought to fit the bill, neutral with a slight treble and bass boost without the switch, bassy sound with the switch. Best of both worlds and you can just use an HSQ filter to turn down the treble if it is too spicy. I was thinking of getting em but the size scared me off. Not in the market for anything that won't fit my ears, even the Moondrop DUSK fits a little weird for me lol The best actual all rounder I think is the U12T. Inoffensive with loads of technicalities. The only con people i've seen people give is that the tonality is too neutral/boring and some others complain about ba timbre. Some say the ThieAudio Valhalla is either slightly better or worse than the U12T but mostly people talk about the shell size and its bassy signature, complaining about the treble lacking air but not detail. I love all rounders but I value bass quality the most which is why I was looking at the Z1R but fit issues scared me off so I'm just off the iem market entirely now. Using the Moondrop DUSK and anything bigger would just be a waste of money for me and my ears. I'm curious though what do you like about the Volare and how do the DUSK and Variations compare to it?

Get ThieAudio Monarch MK4 and have peace.

I actually prefer braindance over monarch. Monarch is a safe choice, bd is something else, it doesn't need to be perfect.

If we assume that all differences in sound are due to frequency response, then any hobbyist with the right information would be able to recreate the frequency response of any iem. Is that a correct statement? If true, then the reason I'd purchase a Thieaudio Monarch MK4 to replace my Meze Alba is because I wanted the sound signature of the MK4 (because that is the sound signature that I liked) but was unable to replicate it via the tools available to me and the eq grit/knowledge necessary to work hard to get to that point. I'd spend more to make up for the shortfall in the tools I had and the eq knowledge I lacked - I'm paying a tax for not having those abilities. Is that a reasonable statement, or am I wrong?

I won't be able to use the correct terms for you, but here's what I experienced. Tuning is really important. I can take my Alba or MP145 and EQ it to a point where I am very happy. $143 - $159. At CanJam, I got to listen to expensive Thieaudio iems (Valhalla, Monarch MK4, V16 Divinity). I could appreciate the clarity of sound and the placement of instruments while listening to the Valhalla and MK4, that was just plain better than my Alba or MP145. But not better enough to warrant me spending 6x - 10x more. The V16 Divinity was a whole 'nuther situation for me. It sounded like God touched me in the brain! Now, guess what? The sound signature of the V16 is pretty similar to that of the MP145 when I look at the graphs. So - my opinion only - once a higher-end iem aligned with my sound preference, the details really stood out (instrument placement and sound clarity for me). The V16 has 16 Knowles and Sonion BA drivers in each ear (Alba has one DD, MP145 has one Planar). Clearly better driver technology - which I appreciated (in my opinion) because the sound signature was closer to what I like. Somebody else might prove me wrong, that's fine. For somebody else, the MK4 will sound fabulous and the V16 will be like, meh. A $200 sound signature you like will likely be a better choice for you than spending $1,000+ on something that doesn't align with your preferences.

Odd diatribe. Are you some kind of mind reader who somehow knows that most IEM buyers are lying to themselves and are actually just getting hoodwinked into wasting money by spending more? And how can you possibly know that IEMs aren’t “worth” their price? Worth is subjective, in the eye of the beholder. I disagree with your central claim that IEM buyers are not “getting quality for what they are paying.” I’ve owned IEMs across a reasonably wide price range from $15 to $1,300. The list of them includes the KZ ATE, Moondrop Aria, 7Hz Timeless, Sony IER-M9, Thieaudio Monarch MK4 and Nightjar Singularity. I also listened to the Elysian Pilgrim and Pilgrim Noir for a week when they were sent around on a demo tour. My source has either been a dongle DAC/amp (L&P W2, Cayin RU7) connected to an iPad or the Chord Mojo 2 + Poly streaming Roon. Each of the IEMs I listed sounds different and the sound quality is strongly, positively correlated with the price of the IEM. So as an example, the $220 7Hz Timeless sounds good and most people would be happy with it, but it delivers wooly, somewhat bloated bass. It’s really noticeably inferior in sound quality when compared to the Monarch MK4 or Nightjar Singularity, both of which sound much better to me. When I consider whether to buy an IEM, I don’t care about aesthetics in the slightest. I use IEMs exclusively at home and neither I nor my wife cares how they look. What I do care about is whether an IEM will last, meaning I greatly prefer IEMs with recessed 2-pin cable receptacles or MMCX connectors and try to make sure that the IEM manufacturer offers good long-term customer support. I won’t spend more than $1,500 on an IEM and think the pricing of TOTL IEMs has become absurd. You can buy a really good 2-channel system that will last forever for the price of some IEMs. You’d have to be very gullible to be “tricked” into buying IEMs by YouTube reviewers or comments from internet randos. Most hobbyists do a fair amount of legwork before buying. Ideally, you attend meets to actually demo IEMs to narrow down to the ones you like. On top of that, it’s worth seeing whether a consensus forms around an IEM among people you personally know or at least trust from their post history on various forums, but only after a new IEM loses its flavor-of-the-month status. And it makes sense to talk to retailers to see if the brand offers good long-term customer support. Finally, headphones offer a different listening experience from IEMs. I own a high-end headphone rig to listen to a set of HD800s. Yes, it offers a more realistic soundstage and better dynamics than IEMs, but the downside is that good full-size open-back headphones (which almost always sound better than closed-backs) don’t block out external noise, they leak noise to people around you, and are heavy and uncomfortable to wear for long periods. IEMs are more “in your head” but I really like how comparatively weightless and comfortable they are and how well they isolate from external noise.

I feel you with the soundstage part. Before getting my monarch mk4 I had some musics that I liked because everything is mixed with no separations. It sure feels weird because it feels like it’s 2 different musics lol

Hard to say what's the best for "neutral" since there's almost always trade-off which is funny as I haven't found any IEM that has achieved decent neutral response (mid-treble according to IEF 2025 target and mid-low according to Harman 2019) with near-perfect diffuse field response (JM-1 target (5128 DF has certain flaws for IEMs as it overphamsizes on the pinna's contribution to the response and IEM is directly fed into the ears)). I think a near-perf. neutral would be low Harman, mid (somewhere between), and treble, IEF 2025. We also have to consider Harmonic Distortion + (Noise) of the setup (ideally at around <= 0.5% at 1 kHz, 94 dB). But honestly, having tested THIEAUDIO Monarch MK4 and Divinity, Moondrop Meteor, and Letshuoer Cadenza 12 on Moonriver 2 Ti at around 70-80 dBa, and compared the diffuse field/freq responses, group delays, and whatnot on some 32-bit 96kHz tracks (a bit pointless but want to make the details like decaying sounds, scratches, etc. are clear enough). As for instrumental separation and imaging, I'd say maybe Divinity has overall best based on how close it matches the JM-1 target, but based on my experience, I can't faithfully say I have noticed audible spatial difference between Meteor, MK4, and Divinity on imaging and instrumental separation. Though, Cadenza doesn't do too well well on treble, and the clarity is noticeable. MK4 is also amazing, but it fleshes out too much detail on high freq, and sometimes, we can hear some unnatural emphasis on breathing or air noises; we can hear those sounds neutral enough on Meteor and Divinity. Also, my hearing is not bad as I can faithfully hear up to \~19.5 kHz and down to 20 Hz with my setup, and I've cleared hearing tests. Though, for treble, I think that Moondrop Meteor really aced it the most neutral out of all of them; I think it might have the most neutral overall treble in all IEMs based on the graphs. For mid-range, honestly, I haven't noticed much difference as all of the them sound exceptionally natural and clear. Now, for the bass region, I think MK4 nailed it the best, and also I think that Meteor does better at bass region than Divinity. So, it depends what region of neutrality you care the most about as there isn't one that aces all of them... In my case, I chose Meteor as I'm way more into treble details. It's also relatively cheaper than others \~$600, and if you can get it from some Chinese stores in China, it can be reduced to around $500 USD. Also, the bass on Meteor is quite punchy and the decaying details are clearly present (if you play at around 70-80 dBa); it's just that it doesn't hit as much as the others.

In case you aren’t sure, you can wait a bit or try to attend some shops/conventions. But if you want to go blind, then I would just elaborate again with bit more detail and tips. I’d say that MK4 isn’t really good if you’re sensitive to treble and your tracks also contain lots of mid-high trebles since if we look at both Harman and IEF preferences, the high treble differs by like 3dB from both curves which would be very bright if you are sensitive. There’s no need to worry about bass as all of them have bass under decent control. Though, if most of your songs don’t contain much high treble (can caused by breathing/air, percussions, violin, overtones…), you can still consider MK4 as it would be the the smoothest/neutral for bass and midrange as the curve sits right between IEF and Harman curve and its DF response almost perfectly overlaps with JM-1 besides for mid-high treble region. Or, in other cases, you can consider V16 as it should provide best overall separation (even mid-high treble) while also having decently smooth/neutral treble (fits IEF-2025) and bass (fits Harman bass + midrange). It’s a combo I also really enjoy as Moondrop Meteor also follows the same pattern besides MM really smoothened that treble to fit IEF and has decent separation too (it’s just that its bass might feel a bit less natural to some given bit higher deviation from JM-1). In a way, Meteor and V16 are very versatile for various tracks where V16 would have more natural overall imaging and Meteor would have more natural treble and as for bass region, I think MM better but that’s more debatable. I’m not sure about other expensive IEMs as I haven’t tried.

Yep, that’s the monarchs for you, I have the same issue with the Mesk MK2, too. Unfortunately, some IEMS require such a deep fit, the comfortability is just not there for long listening sessions. If I know I’m going to be listening for more than a couple of hours, I usually pick up the Noble Audio Spartacus or the U12T.

I A/B the penon archangel against the monarch mk4. Bass def goes to archangel as it has better texture with great kick and hits hard. Midrange is a toss up: monarch mk4 if you like forward midrange sound, whereas archangel sounds balanced and neutral to my ears. Treble on the mk4 is a bit too smooth for my liking, so I prefer the archangel as it has more bite and ironically not having EST drivers I found the archangel to be slightly more airy than the mk4. https://preview.redd.it/xi6f2yy6vonf1.jpeg?width=4000&format=pjpg&auto=webp&s=5f21762a9bcb1ecbccb492f90959e6d7ce086f4f

Great review mate, I’ve tried both and I completely fell in love with the MkIII over the MK4, i agree with every single thing you wrote but I love that midbass on the III’s haha wish here in brazil we had better prices on those, unfortunately thieaudio it’s way out of my league as you pay twice the price cause of taxes. And btw, i think you should invest your time into reviewing more stuff, your writing is brilliant

this is probably the best piece of advice ive ever seen. i had the exact same scenario as OP, where monarchs would hurt my ears after just an hour. after switching to s&s tips, the discomfort is mitigated by quite a bit. however, there are a good amount of kilobuck iems that are more comfortable/smaller, like the 64audio u4s or prestige ltd. would you not recommend to get those instead of the monarch?

The Tea Pro has a little more sub bass emphasis, but the Top Pro is superior in every other area, and I'd strongly recommend it over the Tea Pro. It's probably the best set at that $400-$600 range, and punches well above its weight. Minus maybe the Thieaudio Origin, I'd go so far as to say it's one of (if not the) best sets under a $1000. For context, one of those $1200 sets I referred to above is the recent Monarch MKIV, and it gets more play time than the Monarch, despite being less than half the price. Besides its tuning, it's much more comfortable for long listening sessions than most kilobuck IEMs. It's an all-day set for me.

Very different tunings; the MKIV in its default mode is similar to the MKII, and in its "rumble" mode it is similar to the MKIII, but with a bit more roundness in the mid bass. It's a little less incisive. However, I would not recommend the MKIV for gaming. Besides the fact that emphasized lower frequencies narrow stage (might not be an issue for you in immersive/single-player titles), the MKIV is bulky, with an extended nozzle. Fit/comfort issues are pretty common with the MKIV; I'd consider myself to have larger ear canals than most (I have to use XL tips or large barrel tips like the S&S), and it can be fatiguing, even for me. Sort of hard to see in [these](https://imgur.com/a/mkiv-size-comparison-DrsdZ3G) side-by-sides, but the MKIV definitely suffers from Grand Maestro syndrome. Those odd resonances you're associating with BA timbre, can still be an issue with ESTs and planars. They all have their idiosyncrasies, which is why tuning is much more important than the driver technology. When BA's are pushed to emphasize clarity and detail, as they reach those peaks in the upper mids and treble, that's where you encounter those BA qualities that some people are more sensitive to -- the myth is that a better BA driver doesn't have those qualities, and I don't know that I agree. The irony is, that's why you probably feel it's near perfect; if it were less clear and detailed, you'd likely not hear that BA timbre, but then you'd be missing the clarity and detail. Personally, my favorite gaming IEMs are mostly budget/midif IEMs; the Meze Alba, Simgot EM6L, the Hype 4, and Mega5est Bass+ edition. I run the Hype 4 and Mega5est most often for single-player titles. The Mega5est is probably my favorite for that use case; the slightly bass-boosted JM1 tuning just works really well as an all 'rounder, with that typical meta cleanliness, but with some extra sub bass energy you'd want for immersive games. I can also wear both the Hype 4 and Mega5est all day with no issues. I love the MKIV; it's Thieaudio's best iteration of the Monarch, but definitely wouldn't be my first pick for gaming.

My go-to for most kilobuck/summit-fi IEMs -- which many of them suffer from the same issue, either requiring deeper insertion with a much longer nozzle, or just being larger than other sets since many of them have a much higher driver count -- are the Dunu S&S tips. I have a large collection of tips from SpinFit, Azla, Final Audio, Kbear, Sancai, Divinus, etc. The issue with most of these is the size and shape of the tip itself. They're almost always dome-shaped, but that shape can differ from being globe-like and more rounded in the middle, or consisting of a much shallower taper, with the widest point being near the base. Adding to that, bore size can often force the pressure further outward, making wide-bore tips harder to use with IEMs that require deeper insertion into the ear. Materials also come into play, with tips like Spinfit or Kbear using a much more rigid silicone housing, which can add to discomfort. Where the S&S can help is that they are a consistent barrel-shaped tip; instead of relying on a rounded construction, which can apply pressure in a more narrow location, they provide a larger surface area and distribute pressure much more evenly -- with the added benefit of often improving the seal. These are the same tips I use with the MKIV, where other tips -- like the Divinus Velvets -- are much more fatiguing, requiring me to take a break after a couple of hours. As an aside, you're probably not going to solve your issue by throwing money at another kilobuck IEM. They all suffer from similar issues, and the MKIV is one of the best sets in the segment, competing with IEMs 2-3x its price. It's just a damn good set and one of Thieaudio's best releases (they've ostensibly found a way to put an MKII and MKIII in the same housing). I would, however, recommend the opposite approach; spend less, and find yourself a solid midfi or budget set you can run alongside the MKIV as a daily driver. I give almost as much time to sets like the Top Pro and Mega5est as I do the MKIV, simply because I can wear either of them for an entire day without issue.

thank-you, excellent summary! I will likely get Monarch MK IV, I will try them on first though. The FX17 I want to try those also in person.

Going to buy Monarch MKIV

Did you get the Prestige LTD? If so, has it resolved the forward sounding audio? I have the MK4 myself and was expecting something else when enabling the rumble switch. It sounds rather more of the same (enabling it to me makes it sound more muddy rather than more bassy) rather than a boost in bass impact. I've been thinking about getting the Fiio FX17 but i'm not sure whether that would help.

I wish I came across your post before purchase 🥲, my MKIV arrived 3 days ago and I agree with all your points. The IEM is just a hint too Detailed for me and while it stages pretty well, the Mids are pushed too forward so most of the time, a lot of sounds are placed inside my head and it makes the IEM less enjoyable to listen to even with a good R2R source like SE300. The one good aspect for me is that the Bass is pretty Fun to listen to on some tracks but otherwise, the huge shell, fatiguing listen... It's a pass for me. If you are still looking for something, give 64 Audio Solo a try. I love that set and it is better than the MKIV to my ears.

Still evaluating. There aren’t any graphs of this so I’m taking longer to confirm my findings. But initial take is pretty good so far. Bass seems tighter but just as impactful as the mmk4 (rumble switch off). Mids are difficult to figure out, initial impressions are simply more realistic. Still evaluating the treble. If I boost the bass 3db in the 90 to 120hz range (peak, not shelf), it sounds like a tighter and cleaner mmk4 (w rumble switch on). Hard for me to talk about something without comparing to another iem. Definitely interested in the mest mk2 tho.

Thieaudio monarch Mk4 and be done with. There's no improving from that point, only different flavors

Monarch MK4, because I bought them. Also because I think they are really good. That's the only reason, I'm biased.

It's more of a reference tuning to monitor with. The bass switch is supposed to make it more "fun", but still analytical reference. Overall, it is better suited for a audio producer, otherwise it may come to be disappointing.

Can't find anything wrong with the 4 myself but reading some of these comments makes me think about switching them out for the LTD's.  Any opinions on LTD's vs Mk4's?

Keeping the 4 for it's reference abilities. 

Everything comes down to your preference in music and comfort. Check if you have any previous IEMs or headphones that you really liked, and see if there's a particular genre of music you listen to. Pinpoint exactly what you enjoy in that music. If you like bass, you buy stuff with a lot of bass. You like treble more? You buy something with lots of treble. If you're buying for gaming, just aim for something with a lot of sub-bass and bass. (And stage. Really important for shooters and sh). For comfort if the nozzle is too big for your ear canal, you’ll have a bad experience. Some IEMs can be bulky, and that can also affect comfort. And well, I think this won’t be too useful since you guys are already buying IEMs. Some people can’t appreciate all the sound frequencies (like me), and the effects of IEMs only really kick in after spending a bajillion on high-end ones. Had 1 iem out if each price category and got satisfied only after buying monarchs (spending so much felt like a gut punch). And like it's usually really nice to find someone who already has iems and ask for a listen (this advice literally never works but if you actually manage to find anyone willing it's amazing) Overall you have to choose yourself (what a helpful guide). Stick to the new once (zs and kefine) and then it comes to details.

Monarchs are not V shaped, but not neutral either so you're 50% right.

Long useless post, TL;DR reached endgame. MH334SR good. Started with the KZ ZS1 a long time ago, with many incremental upgrades until I landed on the 7Hz Timeless. Then, after moving to Japan, I replaced it with the Variations paired with a DT990 for gaming. Somewhere along the way, I became that guy who kept making a fuss about cables, claiming they made everything sound so much better. I turned into a file format snob, only wanting to listen to FLAC and DSD. I kept talking about it to my friends (damn, I must have been really annoying). Ultimately, I purchased a used LCD i4 as a reward for enduring all the hard work of labor and finally landing a much better job. It stopped me from wearing headphones entirely since the soundstage and sound quality were more than enough. The bass and soundstage were incredibly addicting. At this point, I started to realize that cables were just snake oil, Bluetooth was a godsend, and my ears didn’t even care when listening to 128kbps audio. Qudelix is life. Recently, I got myself a pair of Diamond 220 speakers. However, they ruined my i4 in a sense that listening to speakers became so enjoyable that I spent less and less time with the i4. It felt like the entire area in front of me was a sound field. It was quite wild to be able to "see" (or feel) sound moving in front of me. The speaker itself looks like "muted", I don't hear sound from the speaker itself. Idk how to describe it haha. I still needed an IEM for outdoor use, though. Demoed the Z1R, Monarch, and others. They were okay, but it was hard to justify their sound when my main IEM was the i4. So, instead of deciding based on sound, I thought, why not prioritize comfort? That’s when I started looking into custom IEMs and came across the MH334SR on sale for 200k yen. Checked the frequency response, Immediately pulled the trigger and went to their clinic the next day to get ear impressions. It took about a month from there until the IEM was completed and delivered to my apartment. Honestly, I wasn’t expecting great bass (I thought it might be bloated) since it’s just a BA. But damn, maybe it’s the seal. It’s definitely not on the same level as the i4’s airy bass, but it’s good enough to satisfy my ears. The mids, highs, and technicalities are fine. At this price point, they’re as resolving as expected, just tuned differently. I listen almost exclusively to Japanese songs. Specifically, those leaning more into vocaloid, UTAU, visual novel OSTs, etc. If I see weeb art, I play it. Artists like DAZBEE, Nanami Urara, and Isekaijoucho are my daily dose. Below is just me trying too hard to explain the sound of the MH334SR: The highs are slightly above my preference (not that the IEM is harsh, but I butchered 4kHz in my i4). However, I got used to it pretty quickly in few hours. All instruments have presence. I don’t have to try hard to distinguish them (which is different from being able to hear all instruments). I can clearly hear vocal harmonies, which is a big plus. Can’t hear the sub-bass (drum) sound in the Aster Lore song at 3:37 - 3:50 though, which is a bit of a bummer (though so far, I’ve only been able to hear it on the Timeless). The beats are satisfying, most likely due to a bump at 200Hz. It’s not bloated, just a nice, punchy drum sound. I love that I don’t have to use EQ at all. I might even replace the Qudelix with something that looks nicer and has a knob in the future. But damn, the comfort is just peak, and the isolation is awesome. It’s close to Etymotics-level isolation without violating my ears. I desire nothing more for IEMs now (more like I don't care that much anymore), but I’ll still visit the shop regularly to demo IEMs since friends often ask for recommendations, especially in the budget range. Hopefully this doesn't make me plunge into speaker rabbit hole which is many times scarier. But so far satisfied since I only listen in very-very low volume anyway.

I tried TheAudio Monarch and Oracle (don't remember Mk numbers) some time ago and wasn't impressed really. The do sound good, and have good technicalities but nowhere near the headphones at this price (Arya or LCD-2C) or substantially better than good quality $200-300 planar IEMs. Tonality is different but that's taste more than anything else. Timeless (1 or 2) is where IEM peaks for me personally, and diminishing return is hitting hard after that. At least based on my hearing abilities.

Honestly for an entry level iem just save up some more for the supermix 4, skip the timeless soundstage is so narrow. Then the next upgrade with honestly be either the Variations or Xenns Top. Final endgame will be the Thieaudio big boys (Monarch, Prestige, Origin). Alternatives would be Elysian endgame range iems too.