The FiiO FT1 is 32Ω at 98.0 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 9.9 dB more than the FT1 to reach the same loudness — 15 mW against 1.6 mW.
| Specification | FT1 | JT1 |
|---|---|---|
| Impedance | 32 Ω | 32 Ω |
| Sensitivity | 98.0 dB/mW | 88.1 dB/mW |
| Sensitivity (voltage) | 112.9 dB/V | 103.0 dB/V |
| Power for 100 dB | 1.6 mW | 15 mW |
| Voltage for 100 dB | 0.23 V | 0.70 V |
| Current for 100 dB | 7.0 mA | 22.0 mA |
| Highest source impedance that leaves them alone (one-eighth rule) | 4.00 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 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 (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 than 63%.
| dB SPL | FT1 power | FT1 voltage | JT1 power | JT1 voltage |
|---|---|---|---|---|
| 80 | 0.02 mW | 23 mV | 0.15 mW | 70 mV |
| 85 | 0.05 mW | 40 mV | 0.49 mW | 0.13 V |
| 90 | 0.16 mW | 71 mV | 1.5 mW | 0.22 V |
| 95 | 0.50 mW | 0.13 V | 4.9 mW | 0.40 V |
| 100 | 1.6 mW | 0.23 V | 15 mW | 0.70 V |
| 105 | 5.0 mW | 0.40 V | 49 mW | 1.25 V |
| Source | Price | Headroom, FT1 | Headroom, JT1 | Output impedance | Noise |
|---|---|---|---|---|---|
| JadeAudio JA11 | $20 | 12.8 dB | 2.9 dB | 0.5 Ω | 1.7 µV |
| FiiO KA11 | $29 | 21.0 dB | 11.1 dB | 0.7 Ω | 1.7 µV |
| FiiO BTR11 | $36 | 12.8 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 12.8 dB of headroom on the FT1 and 2.9 dB on the JT1, its output impedance is 0.5 Ω against a one-eighth limit of 4.00 Ω for both, and its noise figure puts the hiss floor 22 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 | 10Hz-40kHz | not printed | not printed |
| JT1 | 15Hz-30KHz | not printed | not printed |
FiiO prints 10Hz-40kHz for the FT1. 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.
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 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.