Sony IER-Z1R 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 4 of 4 measures.

Sony IER-Z1R
THIEAUDIO Monarch MKIV

HearWiki score

Sound

9.1

9.4

Value

7.3

7.6

Price (USD)

$1,700

$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 7 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 7 years between them, that is a thin return - treat this as a restyle rather than a new platform.

IER-Z1R2018
Monarch MKIV20257 yr newer

Specifications

IER-Z1RMonarch MKIV

Type: Wired IEMs; Wired IEMs
Price (USD): $1,700; $1,150
HearWiki score: 69; 84
Released: 2018; 2025
Availability: Discontinued; Sold new
Driver: hybrid; 2DD + 6BA + 2EST tribrid
Driver type: hybrid; tribrid
Driver configuration: -; 2DD + 6BA + 2EST
Driver size: 12 mm; 8 mm
Drivers per side: -; 10
Impedance: 40 Ω; -
Sensitivity: 103 dB/mW; -
Active noise cancelling: No; -
Weight: 26.1 g; -
Detachable cable: Yes; -

Specification comparison of Sony IER-Z1R vs THIEAUDIO Monarch MKIV
Spec	Sony IER-Z1R	THIEAUDIO Monarch MKIV
Type	Wired IEMs	Wired IEMs
Price (USD)	$1,700	$1,150
HearWiki score	69 / 100 Good	84 / 100 Outstanding
Released	2018	2025
Audio
Driver	hybrid	2DD + 6BA + 2EST tribrid
Driver type	hybrid	tribrid
Driver configuration	-	2DD + 6BA + 2EST
Driver size	12 mm	8 mm
Drivers per side	-	10
Impedance	40 Ω	-
Sensitivity	103 dB/mW	-
Features
Active noise cancelling	No	-
Design
Weight	26.1 g	-
Detachable cable	Yes	-

What reviewers said

Sony IER-Z1R

The Sony IER-Z1R is a flagship hybrid in-ear monitor that prioritizes a powerful, immersive sound with deep, impactful bass and a wide soundstage. Its tuning is far from neutral, favoring excitement and engagement over reference accuracy, making it a top choice for bass lovers despite some ergonomic and midrange compromises. Build quality and technical performance are exemplary, though the fit can be challenging for some users.

Pro:Deep, powerful bass with excellent impact
Pro:Expansive soundstage and strong imaging
Pro:High-quality build and elegant design

Con:Mids can sound recessed or overshadowed
Con:Fit may be uncomfortable for some ears
Con:Requires significant burn-in for optimal performance

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

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

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