Skip to content
HearWiki

Letshuoer S12 Ultra vs Tanchjim FISSION: which should you buy?

Specs, scores and condensed review verdicts for the Letshuoer S12 Ultra vs Tanchjim FISSION, side by side. Where a product has no HearWiki score yet, not enough reviews have been aggregated to rate it.

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.

  • Letshuoer S12 Ultra
  • Tanchjim FISSION
HearWiki score
83
-
Sound
8.6
-
Value
8.9
-
Price (USD)
$170
$130

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

Both shipped in 2025. 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.

  • S12 Ultra2025
  • FISSION2025

Specifications

S12 UltraFISSION
Type
Wired IEMs
Wired IEMs
Price (USD)
$170
$130
HearWiki score
83
Not scored
Released
2025
2025
Availability
Sold new
Sold new
Driver
1 planar magnetic
2× dynamic
Driver type
planar
dynamic
Driver configuration
1 planar magnetic
-
Driver size
14.8 mm
-
Drivers per side
1
2
Frequency response
-
8 Hz - 48 kHz
Impedance
16 Ω
16 Ω
Active noise cancelling
-
No
Connector
-
2-pin 0.78 mm

What reviewers said

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

Tanchjim FISSION

The Tanchjim FISSION is a wired in-ear monitor that pairs two dynamic drivers in a dual-chamber design, using an inner and outer double-magnetic circuit to keep distortion low. It delivers a broad frequency range from 8 Hz to 48 kHz, making it a solid choice for detail-focused listening without active noise cancellation.

  • Pro:Dual dynamic drivers with dual-chamber design for balanced sound
  • Pro:Wide frequency response extends from 8 Hz to 48 kHz
  • Pro:Low distortion thanks to double-magnetic circuit technology
  • Con:No active noise cancellation, so external noise may intrude
  • Con:Requires a wired source, which may not suit all users
  • Con:16-ohm impedance may need a decent source for optimal volume

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 comparisonLetshuoer S12 UltraTanchjim FISSION