Between the AONIC 3 and IER-M9, the AONIC 3 comes out ahead in sensitivity, while the IER-M9 wins on impedance / driver count. Overall, the AONIC 3 scores 56.6 and the IER-M9 scores 54.5 on our Mars Score.
Which should you buy?
These two are nearly even on the Mars Score (56.6 vs 54.5). The decision is not about overall quality — both clear the bar — it is about which specific trade-offs fit your use.
Pick the AONIC 3 if you care most about sensitivity. The biggest gaps in its favor are sensitivity.
Pick the IER-M9 if you care most about impedance / driver count. Its strongest claims are impedance, driver count.
Both ship with comparable detachable cable, so those specs do not separate the two — focus on the differences below.
Bottom line: there is no wrong answer here — match the spec advantages to how you actually use the product. The Mars Score parity says both are well-rounded; the differences are about trade-offs, not quality.
Why Shure - AONIC 3 wins
- ▲Sensitivity — 9.71% more. 113 dB vs 103 dB.
Why Sony - IER-M9 wins
- ▲Impedance — 12.00 Ω less. 18 vs 30.
- ▲Driver count — 4.00 more. 5 vs 1.
Spec comparison
Drivers
| Spec | Shure - AONIC 3 | Sony - IER-M9 |
|---|---|---|
| Driver count | 1 | 5lead |
| Driver types | Single Balanced Armature | 5 Balanced Armature |
| Impedanceⓘ | 30 Ω | 18 Ωlead |
| Sensitivityⓘ | 113 dBlead | 103 dB |
Build
| Spec | Shure - AONIC 3 | Sony - IER-M9 |
|---|---|---|
| Detachable cable | true | true |
| Connector | MMCX | MMCX |
Spec-level deep dives
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