The FiiO F9 Pro ranks #538 out of 865 total In-Ear Headphones for sound quality. See all Headphones rankings for every top pick.
Brand: Fiio
Prices on this page were last checked October 13, 2026 at 3:17 PM UTC. Product prices and availability are accurate as of that date/time and are subject to change; the price and availability shown on Amazon at the time of purchase will apply to the purchase of this product.
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#538 FiiO F9 Pro Discontinued eBay
Pros: Its tonal tilt of +0.11 sits close to the target, so the overall balance is neither dark nor bright. It uses 1 x 9.2mm dynamic + 2 x balanced armature with an easy 28 ohm load.
Cons: Discontinued, so it is mainly found used. Its 2.84 dB spread is less even than the best measured sets.
| Released | 2017 (9 years ago) |
|---|---|
| Connection | Wired |
| Deviation From Target | 2.84 dB standard deviation |
| Driver Type | Hybrid |
| Drivers | 1 x 9.2mm dynamic + 2 x balanced armature |
| Form Factor | In-ear |
| Frequency Response | 15Hz - 40kHz |
| Harman Preference Score | 67 (measured by crinacle, via AutoEQ) |
| Impedance | 28 ohms |
| Sensitivity | 106 dB/mW |
| Tonal Tilt | +0.11 (negative is warmer, positive brighter) |
| Weight | 0 lbs (3.76 g) |
EQ preset to match the Harman target
Set a preamp of -5.1 dB, then add these filters in any parametric equalizer (Wavelet, Equalizer APO, Peace, or a player with parametric EQ). Calculated by AutoEQ from its measured frequency response.
| Filter | Frequency | Gain | Q |
|---|---|---|---|
| Low shelf | 105 Hz | +1.5 dB | 0.70 |
| Peak | 733 Hz | +3.9 dB | 1.87 |
| Peak | 147 Hz | -2.8 dB | 0.81 |
| Peak | 7,715 Hz | -6.4 dB | 1.63 |
| Peak | 5,251 Hz | +5.5 dB | 1.20 |
| High shelf | 10,000 Hz | -0.5 dB | 0.70 |
| Peak | 1,973 Hz | -4.2 dB | 2.08 |
| Peak | 3,014 Hz | +4.8 dB | 3.69 |
| Peak | 1,034 Hz | +2.2 dB | 3.30 |
| Peak | 1,530 Hz | -0.9 dB | 1.62 |
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