THIEAUDIO MONARCH MKII vs THIEAUDIO Monarch MKIV: which should you buy?

On aggregated review scores the THIEAUDIO Monarch MKIV comes out ahead with a HearWiki score of 84. The full breakdown - sub-scores, specs and what reviewers actually said - is below.

Our pick: THIEAUDIO Monarch MKIV - Outstanding overall at around $1149.

Wired IEMs

Score breakdown

Each axis is a 0–10 blend of what reviewers scored, not a lab measurement.

THIEAUDIO Monarch MKIV leads on 3 of 4 measures.

THIEAUDIO MONARCH MKII
THIEAUDIO Monarch MKIV

HearWiki score

Sound

9.0

9.4

Value

6.4

7.6

Price (USD)

$1,000

$1,150

Generation & platform

The scores rank quality. This is the other question: is the newer one actually newer technology, or the same platform in a new shell?

Same generation

The THIEAUDIO Monarch MKIV is 4 years newer, but it is the same generation of hardware: nothing in the radio, the codecs or the noise cancelling separates them. Nothing separates them on convenience features either, so the choice comes down to tuning and price. For 4 years between them, that is a thin return - treat this as a restyle rather than a new platform.

MONARCH MKII2021
Monarch MKIV20254 yr newer

Specifications

MONARCH MKIIMonarch MKIV

Type: Wired IEMs; Wired IEMs
Price (USD): $1,000; $1,150
HearWiki score: 74; 84
Released: 2021; 2025
Availability: Discontinued; Sold new
Driver: tribrid; 2DD + 6BA + 2EST tribrid
Driver type: tribrid; tribrid
Driver configuration: -; 2DD + 6BA + 2EST
Driver size: 10 mm; 8 mm
Drivers per side: -; 10
Impedance: 36 Ω; -
Connector: 2-pin 0.78 mm; -

Specification comparison of THIEAUDIO MONARCH MKII vs THIEAUDIO Monarch MKIV
Spec	THIEAUDIO MONARCH MKII	THIEAUDIO Monarch MKIV
Type	Wired IEMs	Wired IEMs
Price (USD)	$1,000	$1,150
HearWiki score	74 / 100 Great	84 / 100 Outstanding
Released	2021	2025
Audio
Driver	tribrid	2DD + 6BA + 2EST tribrid
Driver type	tribrid	tribrid
Driver configuration	-	2DD + 6BA + 2EST
Driver size	10 mm	8 mm
Drivers per side	-	10
Impedance	36 Ω	-
Design
Connector	2-pin 0.78 mm	-

What reviewers said

THIEAUDIO MONARCH MKII

This in-ear monitor uses a tri-hybrid driver setup, blending a 10 mm dynamic driver with balanced-armature and electrostatic units for a detailed, layered sound. Aimed at critical listeners, it delivers a polished, high-resolution performance that suits both audiophile enjoyment and studio-style monitoring. Its wired, 2-pin connection keeps things straightforward for those who already own quality cables and sources.

Pro:Layered, high-resolution tuning across the frequency range
Pro:Tribrid driver design offers a cohesive blend of dynamics and detail
Pro:Comfortable fit with standard 2-pin connector for easy cable swapping

Con:Requires a quality source and amplifier to shine fully
Con:No noise isolation features, so external sounds can interfere
Con:Bulky shell may not suit smaller ears

THIEAUDIO Monarch MKIV

This flagship in-ear monitor packs a ten-driver hybrid setup—pairing dual 8mm dynamics with six balanced armatures and two electrostatic tweeters—to deliver a reference-grade, studio-neutral signature. It also offers a switchable RUMBLE mode for those who prefer a more pronounced low-end, catering to both purists and bass enthusiasts. The wired-only design focuses on audiophile-grade sound without active noise cancellation.

Pro:Reference-neutral tuning with optional bass boost
Pro:Layered, detailed treble from dual electrostats
Pro:Solid build and premium fit for long sessions

Con:No wireless or ANC options
Con:Large shell may not suit smaller ears
Con:Requires a quality source to shine fully

Summaries are AI-condensed and paraphrased from published reviews and specs - not original hands-on testing. More on our method.

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