The FiiO FT1 Pro is 20Ω at 95.0 dB/mW; the FiiO FT3 (350Ω) is 350Ω at 100.4 dB/mW. This page covers what they ask of an amplifier, not how they sound.
The FT1 Pro needs 5.4 dB more than the FT3 (350Ω) to reach the same loudness — 3.2 mW against 0.91 mW.
| Specification | FT1 Pro | FT3 (350Ω) |
|---|---|---|
| Impedance | 20 Ω | 350 Ω |
| Sensitivity | 95.0 dB/mW | 100.4 dB/mW |
| Sensitivity (voltage) | 112.0 dB/V | 105.0 dB/V |
| Power for 100 dB | 3.2 mW | 0.91 mW |
| Voltage for 100 dB | 0.25 V | 0.56 V |
| Current for 100 dB | 12.6 mA | 1.6 mA |
| Highest source impedance that leaves them alone (one-eighth rule) | 2.50 Ω | 43.75 Ω |
| Sources that reach 100 dB out of 280 | 280 | 280 |
Every source in the database that drives one of them drives the other. On power, the choice between these two changes nothing about what amplifier you need.
20 sources are low enough in output impedance for the FT3 (350Ω) under the one-eighth rule but not for the FT1 Pro (Zoom AMS-22, Arturia MiniFuse 2, Arturia MiniFuse 1, 17 more).
1 source stays below the audible-hiss threshold with the FT3 (350Ω) but crosses it with the FT1 Pro (Schiit Mjolnir 3).
280 of the 280 sources here reach 100 dB on both.
The FT3 (350Ω) is more demanding than 89% of the 567 non-electrostatic models in this database; the FT1 Pro than 68%.
| dB SPL | FT1 Pro power | FT1 Pro voltage | FT3 (350Ω) power | FT3 (350Ω) voltage |
|---|---|---|---|---|
| 80 | 0.03 mW | 25 mV | 9.1 µW | 56 mV |
| 85 | 0.10 mW | 45 mV | 0.03 mW | 0.10 V |
| 90 | 0.32 mW | 80 mV | 0.09 mW | 0.18 V |
| 95 | 1.0 mW | 0.14 V | 0.29 mW | 0.32 V |
| 100 | 3.2 mW | 0.25 V | 0.91 mW | 0.56 V |
| 105 | 10 mW | 0.45 V | 2.9 mW | 1.00 V |
| Source | Price | Headroom, FT1 Pro | Headroom, FT3 (350Ω) | Output impedance | Noise |
|---|---|---|---|---|---|
| JadeAudio JA11 | $20 | 7.7 dB | 4.8 dB | 0.5 Ω | 1.7 µV |
| FiiO KA11 | $29 | 18.5 dB | 13.2 dB | 0.7 Ω | 1.7 µV |
| FiiO BTR11 | $36 | 10.9 dB | 4.5 dB | 0.5 Ω | 8.0 µV |
Of the 280 sources here, 280 reach 100 dB on both. 69 of them also publish an output impedance low enough for both under the one-eighth rule and a noise figure that stays below the audible-hiss threshold with both.
The cheapest of the 69 is the JadeAudio JA11, at $20. It leaves 7.7 dB of headroom on the FT1 Pro and 4.8 dB on the FT3 (350Ω), its output impedance is 0.5 Ω against a one-eighth limit of 2.50 Ω and 43.75 Ω, and its noise figure puts the hiss floor 23 dB and 30 dB below the 20 dB SPL this site treats as the point where a quiet room stops hiding it.
| Model | As printed | Tolerance | Standard |
|---|---|---|---|
| FT1 Pro | 7Hz-40kHz | not printed | not printed |
| FT3 (350Ω) | 7Hz-40kHz | not printed | not printed |
FiiO prints the same thing for both the FT1 Pro and the FT3 (350Ω): 7Hz-40kHz.
FT1 Pro: FiiO prints no specification table for this model at all; the range appears only as a marketing headline on the product page.
Neither range has a tolerance printed beside it, so the matching numbers say little.
Not a measurement; maker by maker.
Both have a page of their own. In full: FiiO FT1 Pro and FiiO FT3 (350Ω). Every figure on this page comes from what FiiO published, or is derived from it — what that maker publishes, counted.