THIEAUDIO Monarch MKIV vs Westone Pro X50: 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 Pro X50

HearWiki score

Sound

9.4

6.9

Value

7.6

4.9

Price (USD)

$1,150

$600

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 2 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.

Monarch MKIV20252 yr newer
Pro X502023

Specifications

Monarch MKIVPro X50

Type: Wired IEMs; Wired IEMs
Price (USD): $1,150; $600
HearWiki score: 84; 57
Released: 2025; 2023
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: -; 20 Hz - 20 kHz
Sound signature: -; bass-heavy
Impedance: -; 45 Ω
Sensitivity: -; 115 dB/mW
Active noise cancelling: -; No
Controls: -; buttons
Weight: -; 6 g
USB-C: -; No

Specification comparison of THIEAUDIO Monarch MKIV vs Westone Pro X50
Spec	THIEAUDIO Monarch MKIV	Westone Pro X50
Type	Wired IEMs	Wired IEMs
Price (USD)	$1,150	$600
HearWiki score	84 / 100 Outstanding	57 / 100 Average
Released	2025	2023
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	-	20 Hz - 20 kHz
Sound signature	-	bass-heavy
Impedance	-	45 Ω
Sensitivity	-	115 dB/mW
Features
Active noise cancelling	-	No
Controls	-	buttons
Design
Weight	-	6 g
USB-C	-	No

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 Pro X50

The Westone Pro X50 is a compact, five-driver wired in-ear monitor that delivers a warm, musical, and engaging sound with strong low-end extension. Its lightweight, ergonomic design ensures all-day comfort, while the included accessory bundle and two-year warranty add to its premium value. The signature leans toward a bass-heavy presentation, which may appeal to some but could be adjusted with EQ for those seeking a flatter response.

Pro:Very comfortable and lightweight design
Pro:Rich, warm sound with good bass extension
Pro:High level of detail and clarity from five balanced-armature drivers

Con:Bass-heavy tuning may not suit all listeners
Con:Requires an external DAC or amp for best performance (wired only)
Con:No active noise cancellation or wireless connectivity

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 Pro X50