The FiiO FT1 Pro is 20Ω at 95.0 dB/mW; the FiiO FT3 (32Ω) is 32Ω at 95.1 dB/mW. This page is only about what they ask of an amplifier — not how they sound, which no specification on either sheet can tell you.
In amplifier terms these two are the same headphone. The gap between what they need for 100 dB is under half a decibel, which is smaller than the step between two clicks of most volume controls.
| Specification | FT1 Pro | FT3 (32Ω) |
|---|---|---|
| Impedance | 20 Ω | 32 Ω |
| Sensitivity | 95.0 dB/mW | 95.1 dB/mW |
| Sensitivity (voltage) | 112.0 dB/V | 110.0 dB/V |
| Power for 100 dB | 3.2 mW | 3.1 mW |
| Voltage for 100 dB | 0.25 V | 0.31 V |
| Current for 100 dB | 12.6 mA | 9.8 mA |
| Highest source impedance that leaves them alone (one-eighth rule) | 2.50 Ω | 4.00 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.
1 source stays below the audible-hiss threshold with the FT3 (32Ω) but crosses it with the FT1 Pro (Schiit Mjolnir 3).
280 of the 280 sources here reach 100 dB on both. That count is about power only — the output-impedance and hiss lines above are separate questions, and a source can pass this one and fail those.
The gap between these two in decibels does not change with volume — it is a property of the two headphones. What changes is the size of the numbers, and it changes fast: every 10 dB costs ten times the power. The row that matters is the one nearest the level you listen at, and for most people that is nearer the top of this table than the bottom.
The FT3 (32Ω) is more demanding than 76% of the 567 non-electrostatic models in this database; the FT1 Pro than 68%. Both figures use the same measure as the rest of the site: whichever runs out first against a 2 V, 100 mW dongle, voltage or power.
| dB SPL | FT1 Pro power | FT1 Pro voltage | FT3 (32Ω) power | FT3 (32Ω) voltage |
|---|---|---|---|---|
| 80 | 0.03 mW | 25 mV | 0.03 mW | 31 mV |
| 85 | 0.10 mW | 45 mV | 0.10 mW | 56 mV |
| 90 | 0.32 mW | 80 mV | 0.31 mW | 99 mV |
| 95 | 1.0 mW | 0.14 V | 0.98 mW | 0.18 V |
| 100 | 3.2 mW | 0.25 V | 3.1 mW | 0.31 V |
| 105 | 10 mW | 0.45 V | 9.8 mW | 0.56 V |
105 dB is included because forum power figures are usually quoted there or higher. It is also a level that damages hearing in minutes — how many minutes is its own calculator.
| Source | Price | Headroom, FT1 Pro | Headroom, FT3 (32Ω) | Output impedance | Noise |
|---|---|---|---|---|---|
| JadeAudio JA11 | $20 | 7.7 dB | 9.9 dB | 0.5 Ω | 1.7 µV |
| FiiO KA11 | $29 | 18.5 dB | 18.1 dB | 0.7 Ω | 1.7 µV |
| FiiO BTR11 | $36 | 10.9 dB | 9.9 dB | 0.5 Ω | 8.0 µV |
Of the 280 sources here, 280 reach 100 dB on both. That is the easy axis. 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 rest either fail one of those or never printed the number at all, and 208 of them are in the second group.
The cheapest of the 69 is the JadeAudio JA11, at $20. It leaves 7.7 dB of headroom on the FT1 Pro and 9.9 dB on the FT3 (32Ω), its output impedance is 0.5 Ω against a one-eighth limit of 2.50 Ω and 4.00 Ω, and its noise figure puts the hiss floor 23 dB and 25 dB below the 20 dB SPL this site treats as the point where a quiet room stops hiding it.
Cheapest that satisfies three published numbers is not the same as best, and none of it is about how either headphone sounds. To put either model against a source this page does not mention, or to change the target loudness, use the amplifier matcher.
| Model | As printed | Tolerance | Standard |
|---|---|---|---|
| FT1 Pro | 7Hz-40kHz | not printed | not printed |
| FT3 (32Ω) | nothing printed | — | — |
FiiO prints 7Hz-40kHz for the FT1 Pro and nothing at all for the FT3 (32Ω).
FT1 Pro: FiiO prints no specification table for this model at all; the range appears only as a marketing headline on the product page.
FT3 (32Ω): FiiO has one FT3 page and it is the 350 Ω version: it prints "Frequency response: 7Hz-40kHz" beside "Impedance: 350Ω". No page of their own covers the 32 Ω FT3, so there is no range printed for this variant — which is not the same as FiiO printing nothing for the FT3.
So one side of this comparison has a frequency-response number and the other does not — which changes less than it looks. The range printed for the FT1 Pro comes with no tolerance beside it, and a range without a ±dB figure says nothing about how loud the headphone is at either end of it: thirty decibels down at the bottom and the sentence would still be true. On the only reading that would have made it a specification, the two sheets say the same amount: nothing.
None of this is a measurement. What each maker publishes, and what it is worth, is set out in the frequency response audit.
Each model has a page of its own with the full source list, the hiss estimate and the provenance of every figure above: FiiO FT1 Pro and FiiO FT3 (32Ω). Each figure on this page is labelled on those pages with where it came from, including the ones FiiO never published — what that maker publishes, counted.