Between the Aria 2 and IE 900, the Aria 2 comes out ahead in several specs, while the IE 900 wins on impedance and sensitivity. Overall, the Aria 2 scores 65.4 and the IE 900 scores 66.4 on our Mars Score.
Which should you buy?
These two are nearly even on the Mars Score (65.4 vs 66.4). The decision isn't about overall quality — both clear the bar — it's about which specific trade-offs fit your use.
The Aria 2 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 IE 900 if you care most about impedance and sensitivity. Its strongest claims are impedance, sensitivity.
Both ship with comparable driver count, detachable cable, so those specs don't 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 tells you both are well-rounded; the differences are about trade-offs, not quality.
Why Moondrop - Aria 2 wins
- No decisive advantages.
Why Sennheiser - IE 900 wins
- ▲Impedance — 16.00 Ω less. 16 vs 32.
- ▲Sensitivity — 0.82% more. 123 dB vs 122 dB.
Spec comparison
Drivers
| Spec | Moondrop - Aria 2 | Sennheiser - IE 900 |
|---|---|---|
| Driver count | 1 | 1 |
| Driver types | Dynamic | Dynamic (X3R) |
| Impedanceⓘ | 32 Ω | 16 Ωlead |
| Sensitivityⓘ | 122 dB | 123 dBlead |
Build
| Spec | Moondrop - Aria 2 | Sennheiser - IE 900 |
|---|---|---|
| Detachable cable | true | true |
| Connector | 0.78mm 2-pinlead | MMCX |
Spec-level deep dives
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