Skip to content
HearWiki

64 Audio U4S vs FiiO FX17: which should you buy?

On aggregated review scores the FiiO FX17 comes out ahead with a HearWiki score of 83. The full breakdown - sub-scores, specs and what reviewers actually said - is below.

Our pick: FiiO FX17 - Outstanding overall at around $1499.

Score breakdown

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

Neither pulls ahead overall - they trade wins across the measures.

  • 64 Audio U4S
  • FiiO FX17
HearWiki score
73
83
Sound
8.5
9.0
Value
6.6
6.0
Price (USD)
$1,100
$1,500

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 FiiO FX17 is 3 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 3 years between them, that is a thin return - treat this as a restyle rather than a new platform.

  • U4S2023
  • FX1720263 yr newer

Specifications

U4SFX17
Type
Wired IEMs
Wired IEMs
Price (USD)
$1,100
$1,500
HearWiki score
73
83
Released
2023
2026
Availability
Discontinued
Sold new
Driver
1DD + 3BA hybrid
1DD + 4BA + 8EST tribrid
Driver type
hybrid
tribrid
Driver configuration
1DD + 3BA
1DD + 4BA + 8EST
Driver size
-
10 mm
Drivers per side
4
13
Impedance
11 Ω
16 Ω
Sensitivity
107 dB/mW
99 dB/mW
Active noise cancelling
No
No
Weight
-
12.2 g
Detachable cable
-
Yes
Connector
-
4.4 mm balanced

What reviewers said

64 Audio U4S

The 64 Audio U4S is a premium hybrid universal IEM that blends a dynamic driver with three balanced armatures to deliver a lively, well-rounded sound. Its tuning strikes a balance between engaging bass and clear treble, offering solid resolution and layering for a versatile listening experience. With an 11-ohm impedance and 107 dB sensitivity, it is easy to drive from most sources.

  • Pro:Energetic and punchy bass response
  • Pro:Smooth lower mids with fast treble
  • Pro:Solid technical performance with good layering
  • Con:Lower mids can feel slightly recessed
  • Con:Price may be steep for some buyers
  • Con:No included cable options for balanced use

FiiO FX17

The FiiO FX17 is a premium wired tribrid IEM that combines a 10mm dynamic driver, four balanced armatures, and eight electrostatic drivers per side for a detailed, multi-layered sound. Its titanium shell and five-way crossover aim to deliver a refined, high-resolution listening experience, while the included 4.4mm balanced cable offers versatility for audiophile setups.

  • Pro:Precision-milled titanium shell for durability and resonance control
  • Pro:Hybrid driver array (1DD + 4BA + 8EST) offers expansive treble and dynamic bass
  • Pro:Swappable plugs on the cable provide flexible connectivity
  • Con:No active noise cancellation, requiring a quiet environment or isolation tips
  • Con:High price point may limit accessibility
  • Con:16-ohm impedance may need a powerful source for optimal performance

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 comparison64 Audio U4SFiiO FX17