Thieaudio Monarch MKIV | Flagship Tribrid Universal IEMs

Take Control of Your Own Sound with Monarch MKIV, Thieaudio's First Signature Series IEM with an Adjustable Tuning Switch (2x) Dynamic, (6x) Balanced Armature + (2x) Electrostatic drivers Successor to the Thieaudio Monarch MKIII Features adjustable tuning switch for versatile sound T6 Aircraft grade aluminum alloy shell Includes Thieaudio's latest modular cable system with 4.4mm + 3.5mm plugs Bloom's Take Building on one of the most acclaimed tribrids in recent memory, the Thieaudio Monarch MKIV pushes the series forward with upgraded materials, greater versatility, and refined sonic performance. The Monarch MKIII was a massive hit for its balance of technical precision and musicality, and the MKIV answers the call for even more flexibility, comfort, and low-end authority without compromising the Monarch’s core identity. Retaining its 10-driver tribrid foundation—dual dynamic drivers, six balanced armatures, and dual ESTs—the MKIV introduces a new CNC-milled aluminum shell for a sturdier, more premium feel. But the real innovation lies in the dual-mode tuning switch: Standard mode offers clean, detailed, reference-grade tuning, while Rumble mode engages a more muscular, bass-enhanced profile for added energy and low-end slam. The result is an IEM that can go from critical listening to guilty-pleasure bass tracks with a flick of a switch. Visually striking and sonically adaptive, the Monarch MKIV represents Thieaudio’s most mature and well-rounded flagship to date. For those who loved the MKIII or are stepping into the Monarch line for the first time, the MKIV offers flagship-level performance with flexibility rarely seen at this level. Read our full review. Custom Tuning at Your Fingertips Switch between studio-neutral and basshead tunings whenever you want. For the first time in Thieaudio’s Signature Series lineup, the Monarch MKIV comes with an adjustable tuning switch. Extensive R&D has led up to a functional tuning switch that is stylish, easy to use, and makes an extensive impact on the tuning. Users can switch between “STANDARD” and “RUMBLE” modes. RUMBLE adds an additional 3dB to the entire sub-bass shelf, increasing both the sub-bass and low-mid power. With RUMBLE, the overall tuning profile becomes thicker, warmer, and more powerful. Monarch MKIV’s tuning switch allows users to enjoy both Monarch’s signature neutral tuning, while giving the option to experience the powerful bass slam like that of the Thieaudio Origin.  T6 Aircraft Grade Aluminum Construction The Monarch MKIV elevates its status by utilizing a premium T6 aluminum alloy shell. Precision CNC engineering achieves our most durable, yet lightweight, shell. Surface hardening also ensures more scratch resistance and corrosion resistance against sweat. Experience the fullness of your music with featherlight comfort in your ears. All New Tuning Profile The Monarch MKIV encompasses both tradition and modernity in its tuning profiles. Standard Mode In STANDARD tuning mode, the MKIV goes back to its roots by bringing back a studio-neutral tonal balance. The sub-bass dishes out a whopping 10dB of hard hitting bass, but with a sharp 150Hz low-mid cutoff, the bass is fast and precise, allowing for a clean midrange. The midrange has been cleaned up to be more neutral between 150Hz and 1kHz, while the treble is more crisp and natural. Compared to the previous generation, the MKIV’s treble focuses more on vocal clarity while eliminating unnecessary upper treble harmonics for a smoother and more candid treble extension. Rumble Mode In RUMBLE mode, the low-mid crossover is loosened, unleashing a more powerful bass and thicker mids. The sub-bass is boosted to 13dB to enable significantly greater thump and low-end presence. The low-mid range at 200Hz to 500Hz is also boosted by 2dB, giving greater body, depth, and texture to bass guitar, male vocals, and fundamental notes of instruments. RUMBLE is designed for those who love a thicker body in their music and want a more engaging bass. IMPACT2 The IMPACT2 (“Impact Squared”) is Thieaudio’s tried and true subwoofer solution consisting of two latest generation of 8mm composite diaphragm drivers arranged in an isobaric design. The new 8mm dynamic driver focuses on speed and hard-hitting slam for a powerful, yet clean sub-bass thump. The usage of two 8mm subwoofers 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. Electrostatic Tweeters The Monarch MKIV completely redesigns EST driver utilization. By more efficiently targeting the treble range of its balanced armature tweeters, the Monarch MKIV can focus the EST tweeters specifically at the 10-40kHz region. This new crossover technique allows smoother treble transition between the BA and EST drivers for a more natural treble timbre, while simultaneously enhancing EST output into the ultra-treble range. The result is a greater treble extension compared to previous generations while sounding smoother and more natural. Enjoy the spacious soundstage, clarity, and air in the sound - more comfortably.  Next Generation Modular Cable System The Monarch MKIV comes with the latest iteration of Thieaudio’s modular cable system: Chocolate. Consisting of ultra pure oxygen-free copper (OFC) wires and silver plated OFC wires, enjoy cleaner and more fuller audio transmission. The modular plug design allows users to switch between 4.4mm balanced and 3.5mm unbalanced plugs for integration with any audio device.  Specifications Driver (2x) IMPACT2 8mm Composite DD (6x) BA (1x) Sonion E50 EST + (1x) Sonion 28UAP Crossover: 4-Way Frequency Response: 10Hz-44kHz Impedance: 10/9 ohms (±1 ohm) @1kHz Sensitivity: 100dB ±1dB @1kHz THD: <1% @1kHz Thieaudio 1 Year Warranty In the Box Thieaudio Monarch MKIV New upgrade cable 3 Sets of ear tips Cable tie Cleaning cloth User manual + After sales service card Monarch MKIV stickers