Wired IEMs
THIEAUDIO Monarch MKIV
84Outstanding
$1,150
Full review dataTHIEAUDIO Monarch MKIV vs Westone ES40: which should you buy?
Specs, scores and condensed review verdicts for the THIEAUDIO Monarch MKIV vs Westone ES40, side by side. Where a product has no HearWiki score yet, not enough reviews have been aggregated to rate it.
Wired IEMs
Westone ES40
Not yet scored
$1,000
Full review dataScore 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 ES40
HearWiki score
84
-
Sound
9.4
-
Value
7.6
-
Price (USD)
$1,150
$1,000
Specifications
Monarch MKIVES40
- Type
- Wired IEMs
- Wired IEMs
- Price (USD)
- $1,150
- $1,000
- HearWiki score
- 84
- Not scored
- Released
- 2025
- 2018
- Availability
- Sold new
- Discontinued
- Driver
- 2DD + 6BA + 2EST tribrid
- 4× balanced armature
- Driver type
- tribrid
- balanced-armature
- Driver configuration
- 2DD + 6BA + 2EST
- -
- Driver size
- 8 mm
- -
- Drivers per side
- 10
- 4
- Frequency response
- -
- 10 Hz - 20 kHz
- Impedance
- -
- 28 Ω
- Sensitivity
- -
- 112 dB/mW
- Controls
- -
- buttons
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 ES40
The Westone ES40 is a premium custom-fit in-ear monitor tailored for professional audio work, delivering detailed and accurate sound through a quad balanced-armature setup. Its personalized shell ensures comfort and isolation, while the 28-ohm impedance and 112 dB sensitivity make it easy to drive from a variety of sources.
- Pro:Custom-fit comfort and isolation
- Pro:Detailed, balanced sound from four drivers
- Pro:High sensitivity for use with portable devices
- Con:Premium price point
- Con:Requires custom fitting process
- Con:Limited to wired use only
Summaries are AI-condensed and paraphrased from published reviews and specs - not original hands-on testing. More on our method.
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