Skip to content
HearWiki

Cozoy D2 vs Hidizs Mermaid MS2: which should you buy?

On aggregated review scores the Cozoy D2 comes out ahead with a HearWiki score of 81. The full breakdown - sub-scores, specs and what reviewers actually said - is below.

Our pick: Cozoy D2 - Outstanding overall at around $55.

Score breakdown

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

Cozoy D2 leads on 4 of 4 measures.

  • Cozoy D2
  • Hidizs Mermaid MS2
HearWiki score
81
62
Sound
8.5
6.8
Value
9.0
7.6
Price (USD)
$55
$63

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 Cozoy D2 is 5 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 5 years between them, that is a thin return - treat this as a restyle rather than a new platform.

  • D220265 yr newer
  • Mermaid MS22021

Specifications

D2Mermaid MS2
Type
Wired IEMs
Wired IEMs
Price (USD)
$55
$63
HearWiki score
81
62
Released
2026
2021
Availability
Sold new
Discontinued
Driver
2DD
2-driver hybrid
Driver type
dynamic
hybrid
Driver configuration
2DD
-
Driver size
-
10.2 mm
Drivers per side
2
2
Frequency response
-
20 Hz - 40 kHz
Impedance
20 Ω
18 Ω
Sensitivity
-
112 dB/mW
Active noise cancelling
-
No
Weight
-
10 g
Detachable cable
-
Yes
USB-C
-
No
Connector
2-pin 0.78 mm
3.5 mm

What reviewers said

Cozoy D2

The Cozoy D2 is a budget-friendly wired IEM that pairs a 6 mm beryllium driver with a 10 mm graphene-composite driver for a dual-dynamic setup. It offers a flexible connection via a 2-pin 0.78 mm cable that includes swappable 3.5 mm and 4.4 mm plugs, catering to both standard and balanced sources. With a 20-ohm impedance, it's easy to drive from most devices.

  • Pro:Dual-driver hybrid design for detailed sound
  • Pro:Interchangeable 3.5 mm and 4.4 mm plugs
  • Pro:Low impedance (20 ohms) for easy pairing
  • Con:No active noise cancellation
  • Con:Wired only, limiting portability
  • Con:Budget build may not suit all users

Hidizs Mermaid MS2

The Hidizs Mermaid MS2 is a budget-friendly hybrid in-ear monitor that pairs a 10.2mm dynamic driver with an additional driver for a balanced, coherent sound. Its lightweight resin shell and detachable cable make it a practical daily driver, while its tuning leans toward a lively, detailed presentation that suits energetic music genres. It offers strong value for its price, though its forward treble may not appeal to those who prefer a smoother, more relaxed listening experience.

  • Pro:Coherent hybrid tuning with good detail retrieval
  • Pro:Lightweight resin shell for comfortable wear
  • Pro:Detachable cable for easy replacement or upgrades
  • Con:Treble can be over-energetic for sensitive listeners
  • Con:Not a universally flattering tuning for all genres
  • Con:Lacks accessories or features beyond the basics

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

Compare something else

Swap either side out, or start again from the picker.

New comparisonCozoy D2Hidizs Mermaid MS2