THIEAUDIO Monarch MKIV vs Westone MACH 50: 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

THIEAUDIO Monarch MKIV

84Outstanding

$1,150

Full review data

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 MKIV
Westone MACH 50

HearWiki score

Sound

9.4

7.2

Value

7.6

5.1

Price (USD)

$1,150

$620

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 3 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 3 years between them, that is a thin return - treat this as a restyle rather than a new platform.

Monarch MKIV20253 yr newer
MACH 502022

Specifications

Monarch MKIVMACH 50

Type: Wired IEMs; Wired IEMs
Price (USD): $1,150; $620
HearWiki score: 84; 62
Released: 2025; 2022
Availability: Sold new; Still sold new
Driver: 2DD + 6BA + 2EST tribrid; 5× balanced armature
Driver type: tribrid; balanced-armature
Driver configuration: 2DD + 6BA + 2EST; -
Driver size: 8 mm; -
Drivers per side: 10; 5
Frequency response: -; 8 Hz - 20 kHz
Impedance: -; 32 Ω
Sensitivity: -; 110 dB/mW
Active noise cancelling: -; No
Controls: -; none
Weight: -; 7.2 g
USB-C: -; No
Connector: -; MMCX

Specification comparison of THIEAUDIO Monarch MKIV vs Westone MACH 50
Spec	THIEAUDIO Monarch MKIV	Westone MACH 50
Type	Wired IEMs	Wired IEMs
Price (USD)	$1,150	$620
HearWiki score	84 / 100 Outstanding	62 / 100 Average
Released	2025	2022
Audio
Driver	2DD + 6BA + 2EST tribrid	5× balanced armature
Driver type	tribrid	balanced-armature
Driver configuration	2DD + 6BA + 2EST	-
Driver size	8 mm	-
Drivers per side	10	5
Frequency response	-	8 Hz - 20 kHz
Impedance	-	32 Ω
Sensitivity	-	110 dB/mW
Features
Active noise cancelling	-	No
Controls	-	none
Design
Weight	-	7.2 g
USB-C	-	No
Connector	-	MMCX

What reviewers said

THIEAUDIO Monarch MKIV

The Monarch MKIV is a flagship in-ear monitor built around a ten-driver tribrid configuration, blending dual 8mm dynamic drivers, six balanced armatures, and two electrostatic tweeters. It offers a studio-neutral sound signature with an additional switchable bass-boost mode for listeners who prefer a more impactful low end.

Pro:Reference-grade neutral tuning with excellent clarity
Pro:Versatile bass boost mode adds flexibility
Pro:Detailed and extended treble from electrostatic tweeters

Con:High price point limits accessibility
Con:Requires a capable source to perform at its best
Con:Large shell may not suit smaller ears

Westone MACH 50

The Westone MACH 50 is a five-driver balanced-armature in-ear monitor designed for a clean, detailed, and midrange-focused sound signature. Its lightweight, compact build and high sensitivity make it easy to drive, while the wired MMCX connection and strong passive isolation cater to listeners seeking a refined, no-frills listening experience. It sits as a capable step up in the Mach lineup, prioritizing clarity in vocals and instruments over heavy bass.

Pro:Excellent midrange clarity and detail
Pro:Very lightweight and comfortable fit
Pro:Easy to drive with high sensitivity

Con:Light on bass weight compared to some rivals
Con:No inline controls or microphone on cable
Con:Wired-only design with no wireless options

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

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New comparison THIEAUDIO Monarch MKIV Westone MACH 50