Moondrop CHU II vs TRN CS4: which should you buy?

On aggregated review scores the Moondrop CHU II comes out ahead with a HearWiki score of 75. The full breakdown - sub-scores, specs and what reviewers actually said - is below.

Our pick: Moondrop CHU II - Great overall at around $19.

Wired IEMs

Score breakdown

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

Moondrop CHU II leads on 3 of 4 measures.

Moondrop CHU II
TRN CS4

HearWiki score

Sound

7.4

4.8

Value

8.7

6.8

Price (USD)

$19

$10

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

Moondrop CHU II (2023) against TRN CS4 (2022). These are 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.

CHU II20231 yr newer
CS42022

Specifications

CHU IICS4

Type: Wired IEMs; Wired IEMs
Price (USD): $19; $10
HearWiki score: 75; 50
Released: 2023; 2022
Availability: Still sold new; Still sold new
Driver: 1DD; 10 mm dynamic
Driver type: dynamic; dynamic
Driver configuration: 1DD; -
Driver size: 10 mm; 10 mm
Drivers per side: 1; 1
Frequency response: -; 20 Hz - 20 kHz
Impedance: 18 Ω; 23 Ω
Sensitivity: -; 118 dB/mW
Active noise cancelling: No; No
Weight: -; 4.2 g
Detachable cable: -; Yes
USB-C: -; Yes
Connector: 2-pin 0.78 mm; 2-pin 0.78 mm

Specification comparison of Moondrop CHU II vs TRN CS4
Spec	Moondrop CHU II	TRN CS4
Type	Wired IEMs	Wired IEMs
Price (USD)	$19	$10
HearWiki score	75 / 100 Great	50 / 100 Weak
Released	2023	2022
Audio
Driver	1DD	10 mm dynamic
Driver type	dynamic	dynamic
Driver configuration	1DD	-
Driver size	10 mm	10 mm
Drivers per side	1	1
Frequency response	-	20 Hz - 20 kHz
Impedance	18 Ω	23 Ω
Sensitivity	-	118 dB/mW
Features
Active noise cancelling	No	No
Design
Weight	-	4.2 g
Detachable cable	-	Yes
USB-C	-	Yes
Connector	2-pin 0.78 mm	2-pin 0.78 mm

What reviewers said

Moondrop CHU II

The Moondrop CHU II is a budget-friendly wired IEM that builds on its predecessor with a more comfortable fit, a detachable 2-pin cable, and a satisfyingly warm yet detailed sound signature. Its 10mm dynamic driver is easy to drive and offers strong performance per dollar, making it a solid entry point for newcomers, though its compact shell can feel slightly weighty and isolation is only average. The tuning leans toward fun with punchy bass, but the treble can occasionally edge into brightness on certain recordings, and the soundstage remains on the narrower side.

Pro:Comfortable and improved fit over the original
Pro:Removable 0.78mm 2-pin cable adds longevity
Pro:Engaging bass-forward tuning with good detail

Con:Treble can become bright or harsh on some tracks
Con:Soundstage is relatively narrow
Con:Slightly heavy build for an IEM

TRN CS4

The TRN CS4 is a very affordable wired IEM built around a single 10mm dynamic driver. It delivers energetic treble and respectable detail for the price, though its stock tuning can come across as sharp; with some tweaks, it offers surprisingly good imaging and soundstage for a budget model. A lightweight, detachable-cable design adds value at this low cost.

Pro:Strong treble energy
Pro:Decent detail retrieval
Pro:Surprisingly good imaging and soundstage for the price

Con:Can sound harsh out of the box
Con:Not especially polished stock tuning
Con:Limited frequency range

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

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