Where they actually differ
The most decisive specs, ranked by how much they matter — before the full spec table.
| Spec | Etymotic - ER4XR | Shure - AONIC 3 |
|---|---|---|
| Sensitivity | 98 dB | 113 dB |
| Impedance | 45 Ω | 30 Ω |
Between the ER4XR and AONIC 3, the ER4XR comes out ahead in several specs, while the AONIC 3 wins on sensitivity / impedance. Overall, the ER4XR scores 39.7 and the AONIC 3 scores 56.6 on our Mars Score.
Which should you buy?
The AONIC 3 is the clear pick on raw spec strength, leading by 16.9 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 does not pull ahead on any single popular-comparison spec — its strengths sit in the spec-table groups rather than the headline advantages.
Pick the AONIC 3 if you care most about sensitivity / impedance. Its strongest claims are sensitivity, impedance. The single most decisive one: Sensitivity — 15.31% more. 113 dB vs 98 dB.
Both ship with comparable driver count, detachable cable, so those specs do not separate the two — focus on the differences below.
Bottom line: the AONIC 3 is the safer default. The other model is the right choice only when its specific advantages line up with your priorities.
Which should you buy: Etymotic - ER4XR or Shure - AONIC 3?
Shure - AONIC 3 leads the current Mars Score by 16.9 points.The more useful decision is the trade-off behind that result: compare impedance, sensitivity against the way you will actually use the product.
Choose Etymotic - ER4XR if…
Etymotic - ER4XR does not lead a decisive measured field here, so choose it for price, ecosystem, design, or availability when those matter more to you.
Choose Shure - AONIC 3 if…
Shure - AONIC 3 has the measurable edge on sensitivity db, impedance ohm.
This is a structured comparison of the published catalog values. It is not a claim of identical real-world performance across every workload; use the linked spec drill-downs and methodology page to inspect the inputs.
Why Etymotic - ER4XR wins
- No decisive advantages.
Why Shure - AONIC 3 wins
- ▲Sensitivity — 15.31% more. 113 dB vs 98 dB.
- ▲Impedance — 15.00 Ω less. 30 vs 45.
Spec comparison
Drivers
| Spec | Etymotic - ER4XR | Shure - AONIC 3 |
|---|---|---|
| Driver count | 1 | 1 |
| Driver types | Balanced Armature | Single Balanced Armature |
| Impedanceⓘ | 45 Ω | 30 Ωlead |
| Sensitivityⓘ | 98 dB | 113 dBlead |
Build
| Spec | Etymotic - ER4XR | Shure - AONIC 3 |
|---|---|---|
| Detachable cable | true | true |
| Connector | MMCX | MMCX |