Kinera Celest Relentless vs Letshuoer S12 Ultra: which should you buy?

On aggregated review scores the Letshuoer S12 Ultra comes out ahead with a HearWiki score of 83. The full breakdown - sub-scores, specs and what reviewers actually said - is below.

Our pick: Letshuoer S12 Ultra - Outstanding overall at around $169.

Wired IEMs

Score breakdown

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

Letshuoer S12 Ultra leads on 3 of 4 measures.

Kinera Celest Relentless
Letshuoer S12 Ultra

HearWiki score

Sound

7.4

8.6

Value

6.4

8.9

Price (USD)

$170

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

Letshuoer S12 Ultra (2025) against Kinera Celest Relentless (2024). 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.

Celest Relentless2024
S12 Ultra20251 yr newer

Specifications

Celest RelentlessS12 Ultra

Type: Wired IEMs; Wired IEMs
Price (USD): $170; $170
HearWiki score: 68; 83
Released: 2024; 2025
Availability: Discontinued; Sold new
Driver: 1DD + 6BA hybrid; 1 planar magnetic
Driver type: hybrid; planar
Driver configuration: 1DD + 6BA; 1 planar magnetic
Driver size: -; 14.8 mm
Drivers per side: 7; 1
Impedance: 27 Ω; 16 Ω
Detachable cable: Yes; -
Connector: 2-pin 0.78 mm; -

Specification comparison of Kinera Celest Relentless vs Letshuoer S12 Ultra
Spec	Kinera Celest Relentless	Letshuoer S12 Ultra
Type	Wired IEMs	Wired IEMs
Price (USD)	$170	$170
HearWiki score	68 / 100 Good	83 / 100 Outstanding
Released	2024	2025
Audio
Driver	1DD + 6BA hybrid	1 planar magnetic
Driver type	hybrid	planar
Driver configuration	1DD + 6BA	1 planar magnetic
Driver size	-	14.8 mm
Drivers per side	7	1
Impedance	27 Ω	16 Ω
Design
Detachable cable	Yes	-
Connector	2-pin 0.78 mm	-

What reviewers said

Kinera Celest Relentless

This hybrid in-ear monitor from Kinera's Celest range packs seven drivers—one dynamic and six balanced-armature—into a wired design. It features a detachable cable with modular terminations, catering to audiophiles who prefer a flexible, high-resolution listening setup without wireless features.

Pro:Rich, detailed sound from a seven-driver hybrid configuration
Pro:Detachable modular cable offers versatility with different sources
Pro:Compact hybrid design suits critical listening at a mid-range price

Con:No active noise cancellation, requiring a quiet environment or isolation tips
Con:Requires a wired source, limiting convenience for mobile use
Con:May need a capable amplifier to fully drive the 27-ohm load

Letshuoer S12 Ultra

The Letshuoer S12 Ultra is a wired in-ear monitor built around a single 14.8mm planar magnetic driver housed in a lightweight aluminum shell. It delivers the signature planar sound of the S12 line—fast, detailed, and punchy—in a refreshed design aimed at hi-fi enthusiasts. With a low 16-ohm impedance, it pairs easily with most sources, though it lacks any active noise cancellation.

Pro:Fast, detailed planar sound with strong dynamics
Pro:Lightweight and sturdy aluminum-alloy build
Pro:Easy to drive thanks to low impedance

Con:No noise cancellation or isolation features
Con:Planar timbre may not suit all listeners
Con:Cable and accessories are basic for the price

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 comparison Kinera Celest Relentless Letshuoer S12 Ultra