Where they actually differ
The most decisive specs, ranked by how much they matter — before the full spec table.
| Spec | Sony - IER-M9 | Truthear - Nova |
|---|---|---|
| Sensitivity | 103 dB | 123 dB |
| Impedance | 18 Ω | 15 Ω |
Between the IER-M9 and Nova, the IER-M9 comes out ahead in several specs, while the Nova wins on sensitivity / impedance. Overall, the IER-M9 scores 54.5 and the Nova scores 73.9 on our Mars Score.
Which should you buy?
The Nova is the clear pick on raw spec strength, leading by 19.4 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 IER-M9 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 Nova if you care most about sensitivity / impedance. Its strongest claims are sensitivity, impedance. The single most decisive one: Sensitivity — 19.42% more. 123 dB vs 103 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 Nova 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: Sony - IER-M9 or Truthear - Nova?
Truthear - Nova leads the current Mars Score by 19.4 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 Sony - IER-M9 if…
Sony - IER-M9 does not lead a decisive measured field here, so choose it for price, ecosystem, design, or availability when those matter more to you.
Choose Truthear - Nova if…
Truthear - Nova 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 Sony - IER-M9 wins
- No decisive advantages.
Why Truthear - Nova wins
- ▲Sensitivity — 19.42% more. 123 dB vs 103 dB.
- ▲Impedance — 3.00 Ω less. 15 vs 18.
Spec comparison
Drivers
| Spec | Sony - IER-M9 | Truthear - Nova |
|---|---|---|
| Driver count | 5 | 5 |
| Driver types | 5 Balanced Armature | 1DD + 4BA Hybrid |
| Impedanceⓘ | 18 Ω | 15 Ωlead |
| Sensitivityⓘ | 103 dB | 123 dBlead |
Build
| Spec | Sony - IER-M9 | Truthear - Nova |
|---|---|---|
| Detachable cable | true | true |
| Connector | MMCX | 0.78mm 2-pinlead |