Thieaudio Monarch MKIII | Flagship Tribrid Universal IEMs

A Brilliantly Re-engineered Threequel: ThieAudio Enhances Their Tribrid Legend with the Monarch MKIII 2 Dynamic drivers, 6 Balanced Armatures, and 2 Electrostatic drivers Enhanced Ultra-treble Output: now features Sonion's EST drivers and increased frequencies for improved staging and resolution Improved Bass Quality: enjoy better quality bass without sacrificing tonal integrity with ThieAudio's IMPACT2 subwoofer innovation Upgraded thicker 22AWG stock cable with modular plug design including 2.5mm, 3.5mm, and 4.4mm smart-switch plugs (x6) shell colors with (x15) faceplate styles now available for a customizable finish Check out our measurement of Monarch MKIII Read our 2025 Thieaudio Buyer's Guide! Bloom's Take With the Monarch MK2, ThieAudio captured the highly resolving nature and micro-detail presentation of a flagship experience and delivered them with impressive value for the money. It was easily a best-seller IEM, earned a seat at the table of Bloom Audio's "Best Bang for your Buck" IEMs, and was rated as one of the best IEMs in the world by a number of reviewers and critics. These are extremely big shoes to fill... but ThieAudio may have done just that with the Monarch MK3. The MK3 successfully maintains a core tuning balance and delivers an elevated level of technical performance with excellent bass extension, natural and lifelike mids, and improved treble that provides sparkle and shimmer without sibilance and stabbing. Additionally, the imaging and soundstage are a clear standout. The packaging and accessory kit for the MK3 remains essentially the same and is largely shared across ThieAudio’s lineup. However, the stock cable has changed and is more akin to the Oracle MKII cable. And while the new default faceplate is gorgeous, one of the big draws of the MK3 is the range of customizations available with the shells and faceplates offering about 80 possible combinations making this a special IEM. Whether or not you love the changes from the MK2, the price, performance, and design make a really compelling case for Monarch MK3 as a near-flagship quality $1000 IEM that approaches "bass-head" territory. Read our full review here. IMPACT2 IMPACT2 (“Impact Squared”) is ThieAudio's latest technological innovation to change the personalized audio industry. IMPACT2 is a new subwoofer solution consisting of (x2) 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 the in-house isobaric chamber design keeps the frequency and pressure constant. This means you can enjoy better quality bass without sacrificing tonal integrity. Enhanced Ultra-Treble Output The Monarch MKIII has been updated with Sonion’s latest EST drivers and re-tuned to better exhibit their full potentials. Thanks to the 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 this extension. Balanced Tonal Signature At the core of the MKIII is a commitment to tonal excellence. It retains a studio-monitor like tonal signature with a focused sub-bass impact for a clean, natural, 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, the MKIII mids have been revamped to better separate respective driver ranges for maximum output while minimizing the THD. This means the mids 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. Specifications Drivers: Sonion EST, Knowles DWFK 31785 (x2), Sonio 28UAP (x1), IMPACT2 (x2 10mm Composite DD) Crossover: 4-Way Passive with 4 Sound Bores Sensitivity: 99dB @ 1kHz (+/- 1dB) Driver Impedance: 20Ω Frequency Response: 20Hz-40kHz Cable: 4' 22AWG 6N OCC Silver-plated and Graphene Silver-plated Termination: 2-pin 0.78mm with (x3) modular Smart-switch (2.5mm, 3.5mm, 4.4mm)