Thieaudio Monarch MKIII impressions, reviews, and pictures thread
Aug 5, 2023 at 3:44 PM Thread Starter Post #1 of 404


1000+ Head-Fier
Dec 11, 2012
2DD+6BA+2EST Flagship IEM

Technical Details


IMPACT² (2 x 10mm Composite DD), Knowles DWFK 31785 (x2), Sonion 28UAP (x1), Sonion EST


4-Way Passive Crossover with 4 Sound Bores.


99dB @ 1kHz (+/- 1dB)


20 ohms




1.2 meter 22AWG 6N OCC Silver-Plated and Graphene Silver-Plated Cable

Taken from Linsoul's product page:

IMPACT²: THIEAUDIO's latest innovation in personalized audio with a powerful subwoofer solution using isobaric design and composite diaphragm drivers.
Enhanced Ultra-Treble Output: The Monarch MKIII now features Sonion's electrostatic drivers and increased frequencies for a more comprehensive upper frequency extension, resulting in improved staging and resolution.
Balanced Tonal Signature: The Monarch MKIII maintains a studio-monitor-like tonal excellence with clean, natural, and detailed sound, while offering a focused sub-bass impact.
Improved Bass Quality: The addition of another 10mm subwoofer in IMPACT² enhances the power and texture of the bass without compromising tonal integrity, providing better bass quality for an immersive audio experience.

IMPACT² is a new subwoofer solution consisting of two 10mm composite diaphragm drivers arranged in an isobaric design. The addition of another 10mm subwoofer significantly enhances the power and texture of the bass, while our in-house isobaric chamber design keeps the frequency and pressure constant. This means you can enjoy better quality bass without sacrificing tonal integrity.

With updated drivers, tuning strategies, and significantly improved ergonomics, the Monarch MKIII offers the legendary performance of the MKII with enhanced technicalities and comfort.

The Monarch MKIII has been updated with Sonion’s latest electrostatic (EST) drivers and re-tuned to better exhibit these drivers’ full potentials. Thanks to our new tuning strategy, the ultra-treble frequencies at +15kHz to 20kHz have been increased for a more comprehensive upper frequency extension. Compared to its predecessor, the Monarch MKIII will have a greater sense of staging, atmosphere, and an overall enhancement in perceived resolution thanks to the treble extension.

Balanced Tonal Signature​

At the core of the Monarch MKIII is THIEAUDIO’s commitment to tonal excellence. The Monarch MKIII retains a studio-monitor like tonal signature with a focused sub-bass impact for a clean, natural, and detailed sound. Engineered with a true 4-way crossover with 9 separate passive components, the Monarch MKIII stays true to its tonal legacy. Thanks to IMPACT² , the subbass is punchier, but the mids from 200Hz to 800Hz retain their ruler-flat neutrality. This tonality of the mids mimics the true sound of studio monitors used in recording studios to deliver accurate audio reproduction.

Furthermore, compared to its predecessors, the Monarch MKIII mids have been revamped with a new tuning strategy, which better separates respective driver ranges to maximize output while minimizing the total harmonic distortion. This means the mids on the MKIII will sound higher in resolution while retaining the same monitor-esque tonality. The treble has also been slightly re-tuned to offer more coherency throughout the region, as well as little more clarity and definition. This slight tonal modification better mixes with the renewed ultra-treble response, providing a more crisp sound signature.

Medical Grade Resin Housing​

Each Monarch MKIII unit is individually handmade by our dedicated engineers. The housing is constructed from 3D-printed medical-grade resin, which is safe on the skin and durable. Additionally, each faceplate of the Monarch MKIII is individually decorated and coated, presenting a truly bespoke experience.

Upgraded Modular Cable​

The Monarch MKIII has been upgraded with Thieaudio’s latest modular cable. The upgraded cable is composed of thicker 22AWG 6N OCC silver-plated and graphene silver-plated composite wires. This upgrade in cable materials provides a little more clarity and refinement compared to the previous generation of Thieaudio’s modular cables. With three separate interchangeable plugs at 3.5mm single, 4.4mm balanced, and 2.5mm balanced terminations, you can easily pair the Monarch MKIII with any device, without changing cables.


Monarch MKIII HBB Graph.jpg

Monarch MKIII Elise Audio Graph.jpg

Monarch MKIII TechPowerUp Graph.jpg

Monarch MKIII HeadphonesDotCom Graph.jpg


Headphonics' written review by @marcusd

Bloom Audio's written review's written review by @FcConstruct

Headphonia's written review's written review

Not allowed to link HBB's video on head-fi

Where to purchase
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Aug 5, 2023 at 3:49 PM Post #2 of 404
I don't do reviews, so here's my first impressions:

The packaging, presentation, and accessories is not so good for a kilobuck IEM. Cable is pretty nice but not the nicest at or around this price. Decent enough to use I suppose.

The shell is very thick and chunky, but it's lightweight, smooth, and ergonomic, so it's comfortable once you find the right tips for your ear shape and size. Small ears beware.

Faceplates all look amazing, even the default one. Some of the faceplate designs are really beautiful and it will be hard not to spend 10-15% the cost of the IEM to have a more unique version of this IEM, but I think it's a ripoff. $100-$150 is a bit ridiculous for bling in my opinion, but people spending $1,000 for an IEM probably won't mind ponying up more money for extra bling. Very smart of ThieAudio/Linsoul to send out the premium faceplate options to reviewers so they can make their audience want to buy the blinged out versions.

Sound quality is just amazing. It will be tough to find a better all-around IEM at $1k, in my opinion. Some IEMs might do some things better than the Monarch MkIII at around this price, but probably won't be so well rounded and great at replaying all music genres like the MkIII is able to do.

Initial impressions are very, very good. Deep rumbling bass, good slam, but not at basshead level in my opinion. Not boomy or muddy bass. Really satisfying. Both the low end and highs extends for days. Bass also has amazing texture. Those double 10mm DDs are doing some work!

Mids and highs are very high quality. Lush and warm, yet sparkly and precise. No sibilance. Tonality is great. Imaging, soundstage, details are all insanely good. Basically, technicalities are all great. Very resolving IEM with a lot of microdetails.

SpinFit W1 and AZLA SednaEarfitLight Short are the eartips I'm currently using with the Monarch MkIII.

Highly recommend this IEM if you want an engaging, fun, highly technical IEM with amazing timbre, incisiveness, and dynamics.

Monarch MK3-6.jpg

Monarch MK3-4.jpg

Monarch MKIII Ear-2.jpg
Aug 5, 2023 at 5:16 PM Post #3 of 404
how is the size vs the mk2? Loved the mk2 sound but the shell was a bit too big for comfort. Not far off, though.
Aug 5, 2023 at 5:23 PM Post #4 of 404
how is the size vs the mk2? Loved the mk2 sound but the shell was a bit too big for comfort. Not far off, though.
MK3 is bigger but more ergonomic so it might be more comfortable. It’s also slightly thinner on some sides. Won’t know for sure unless you try it yourself.
Aug 5, 2023 at 5:30 PM Post #5 of 404
If anyone is familiar with the size/comfort of the Sony wf-1000xm4 and the monarch mk 3, I'd love to hear how they compare since I'm afraid the monarch might be too big and I already consider the Sony to be on the bigger size of things (but still very wearable).
Aug 6, 2023 at 12:39 PM Post #8 of 404
Aug 6, 2023 at 12:41 PM Post #9 of 404
Aug 6, 2023 at 3:16 PM Post #11 of 404
Linsoul published their own video on the mk3....couldn't do much worse. The text was read without comprehension or any actual interest by a lady with strange manicure...their videos are not up to the level of their iems for sure

Here it is.
Those were poorly fitting detachable nails, ew.
The graph from video shows more difference in bass and treble than previously posted measurements and more inline with sonic impressions.
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Aug 6, 2023 at 10:08 PM Post #13 of 404
Curious of any impressions of these vs the U4s or the Mext.
Aug 6, 2023 at 11:45 PM Post #15 of 404
Curious of any impressions of these vs the U4s or the Mext. wrote a comparisons article, including a short comparison with the U4s.

The 64 Audio U4s is our first recommendation for anyone looking for a kilobuck IEM. It opts for a fun bassy signature that doesn’t sacrifice tonal coherency. As such, it doesn’t quite compare to the carefully-balanced tuning of the MkII. The MkIII is closer in spirit but is still better tuned compared to the U4s. The best way I can describe the midrange is that the MkII is clean, the MkIII is slightly warm, and the U4s is thick. The U4s brings a weightier timbre and heightened dynamics which makes it such an enjoyable listen. And really, that’s what sets the U4s apart. Though it doesn’t outdo the MkIII in resolving ability nor does it come close to the treble performance of the MkII, the fun, easy-going nature of the U4s is why it’s such an easy recommendation for someone looking to get into the game.

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