The FiiO FT1 Pro is 20Ω at 95.0 dB/mW; the FiiO JT1 is 32Ω at 88.1 dB/mW. This page covers what they ask of an amplifier, not how they sound.
The JT1 needs 6.9 dB more than the FT1 Pro to reach the same loudness — 15 mW against 3.2 mW.
| Specification | FT1 Pro | JT1 |
|---|---|---|
| Impedance | 20 Ω | 32 Ω |
| Sensitivity | 95.0 dB/mW | 88.1 dB/mW |
| Sensitivity (voltage) | 112.0 dB/V | 103.0 dB/V |
| Power for 100 dB | 3.2 mW | 15 mW |
| Voltage for 100 dB | 0.25 V | 0.70 V |
| Current for 100 dB | 12.6 mA | 22.0 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 | 278 |
2 of the 280 sources have the power for the FT1 Pro but not for the JT1 — Apple USB-C dongle (EU), Steinberg UR22C.
1 source stays below the audible-hiss threshold with the JT1 but crosses it with the FT1 Pro (Schiit Mjolnir 3).
278 of the 280 sources here reach 100 dB on both.
The JT1 is more demanding than 93% of the 567 non-electrostatic models in this database; the FT1 Pro than 68%.
| dB SPL | FT1 Pro power | FT1 Pro voltage | JT1 power | JT1 voltage |
|---|---|---|---|---|
| 80 | 0.03 mW | 25 mV | 0.15 mW | 70 mV |
| 85 | 0.10 mW | 45 mV | 0.49 mW | 0.13 V |
| 90 | 0.32 mW | 80 mV | 1.5 mW | 0.22 V |
| 95 | 1.0 mW | 0.14 V | 4.9 mW | 0.40 V |
| 100 | 3.2 mW | 0.25 V | 15 mW | 0.70 V |
| 105 | 10 mW | 0.45 V | 49 mW | 1.25 V |
| Source | Price | Headroom, FT1 Pro | Headroom, JT1 | Output impedance | Noise |
|---|---|---|---|---|---|
| JadeAudio JA11 | $20 | 7.7 dB | 2.9 dB | 0.5 Ω | 1.7 µV |
| FiiO KA11 | $29 | 18.5 dB | 11.1 dB | 0.7 Ω | 1.7 µV |
| FiiO BTR11 | $36 | 10.9 dB | 2.9 dB | 0.5 Ω | 8.0 µV |
Of the 280 sources here, 278 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 2.9 dB on the JT1, 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 32 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 |
| JT1 | 15Hz-30KHz | not printed | not printed |
FiiO prints 7Hz-40kHz for the FT1 Pro. FiiO's German distributor shop lists 15Hz-30KHz for the JT1. That figure stands on FiiO's German distributor shop, not on a document published by the maker.
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 a wider range on one sheet is not deeper bass or more treble.
Not a measurement; maker by maker.
Both have a page of their own. In full: FiiO FT1 Pro and FiiO JT1. 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.