Between the ER4XR and ZAR, the ER4XR comes out ahead in several specs, while the ZAR wins on impedance and sensitivity. Overall, the ER4XR scores 39.7 and the ZAR scores 65.4 on our Mars Score.
Which should you buy?
The ZAR is the clear pick on raw spec strength, leading by 25.7 points on the Mars Score. The margin is wide enough that the underdog only makes sense if its individual strengths line up with what you specifically need.
The ER4XR doesn't pull ahead on any single popular-comparison spec — its strengths sit in the spec table groups rather than the headline advantages.
Pick the ZAR if you care most about impedance and sensitivity. Its strongest claims are impedance, sensitivity, driver count.
Both ship with comparable detachable cable, so those specs don't separate the two — focus on the differences below.
Bottom line: the ZAR is the safer default. The other model is the right choice only when its specific advantages line up with your priorities.
Why Etymotic - ER4XR wins
- No decisive advantages.
Why KZ - ZAR wins
- ▲Impedance — 19.00 Ω less. 26 vs 45.
- ▲Sensitivity — 10.20% more. 108 dB vs 98 dB.
- ▲Driver count — 7.00 more. 8 vs 1.
Spec comparison
Drivers
| Spec | Etymotic - ER4XR | KZ - ZAR |
|---|---|---|
| Driver count | 1 | 8lead |
| Driver types | Balanced Armature | 1DD + 7BA Hybrid |
| Impedanceⓘ | 45 Ω | 26 Ωlead |
| Sensitivityⓘ | 98 dB | 108 dBlead |
Build
| Spec | Etymotic - ER4XR | KZ - ZAR |
|---|---|---|
| Detachable cable | true | true |
| Connector | MMCX | 0.78mm 2-pinlead |
Spec-level deep dives
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