KZ Symphony 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.

KZ Symphony
Letshuoer S12 Ultra

HearWiki score

Sound

6.1

8.6

Value

5.7

8.9

Price (USD)

$85

$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 KZ Symphony (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.

Symphony2024
S12 Ultra20251 yr newer

Specifications

SymphonyS12 Ultra

Type: Wired IEMs; Wired IEMs
Price (USD): $85; $170
HearWiki score: 54; 83
Released: 2024; 2025
Availability: Still sold new; Sold new
Driver: 2-driver hybrid; 1 planar magnetic
Driver type: hybrid; planar
Driver configuration: -; 1 planar magnetic
Driver size: 13.2 mm; 14.8 mm
Drivers per side: 2; 1
Frequency response: 20 Hz - 40 kHz; -
Impedance: 18 Ω; 16 Ω
Sensitivity: 95 dB/mW; -
Active noise cancelling: No; -
Connector: 3.5 mm; -

Specification comparison of KZ Symphony vs Letshuoer S12 Ultra
Spec	KZ Symphony	Letshuoer S12 Ultra
Type	Wired IEMs	Wired IEMs
Price (USD)	$85	$170
HearWiki score	54 / 100 Average	83 / 100 Outstanding
Released	2024	2025
Audio
Driver	2-driver hybrid	1 planar magnetic
Driver type	hybrid	planar
Driver configuration	-	1 planar magnetic
Driver size	13.2 mm	14.8 mm
Drivers per side	2	1
Frequency response	20 Hz - 40 kHz	-
Impedance	18 Ω	16 Ω
Sensitivity	95 dB/mW	-
Features
Active noise cancelling	No	-
Design
Connector	3.5 mm	-

What reviewers said

KZ Symphony

The KZ Symphony is a wired hybrid in-ear monitor that pairs a 13.2mm dynamic driver with a balanced armature for a punchy, detailed sound. Its build feels solid for the price, but the tuning leans heavily V-shaped with a bright treble and recessed mids, which may not suit everyone. Technicalities like microdetail are above average, though the accessory package is basic.

Pro:Solid build quality
Pro:Strong sub-bass impact
Pro:Good treble microdetail and resolution

Con:Very V-shaped tuning with recessed mids
Con:Bright treble can be fatiguing
Con:Timbre sounds unnatural at times

Letshuoer S12 Ultra

The Letshuoer S12 Ultra is a wired in-ear monitor that delivers Hi-Fi sound through a single 14.8mm planar magnetic driver housed in a lightweight aluminum-alloy shell. Aimed at music enthusiasts, it offers the signature planar-driver clarity and detail of the S12 series in a refreshed design, without any active noise cancellation or wireless features. Priced around $169, it's a straightforward, high-performance option for wired listening.

Pro:Detailed and fast planar magnetic sound
Pro:Lightweight and durable aluminum-alloy build
Pro:Accurate bass response with low distortion

Con:Requires a wired connection, no wireless freedom
Con:No active noise cancellation for noisy environments
Con:Open-back style may leak sound in quiet settings

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

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New comparison KZ Symphony Letshuoer S12 Ultra