FT3 (32Ω) vs JT1: which needs more amplifier?

The FiiO FT3 (32Ω) is 32Ω at 95.1 dB/mW; the FiiO JT1 is 32Ω at 88.1 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.

The JT1 needs 7.0 dB more than the FT3 (32Ω) to reach the same loudness — 15 mW against 3.1 mW.

The numbers that decide it

SpecificationFT3 (32Ω)JT1
Impedance32 Ω32 Ω
Sensitivity95.1 dB/mW88.1 dB/mW
Sensitivity (voltage)110.0 dB/V103.0 dB/V
Power for 100 dB3.1 mW15 mW
Voltage for 100 dB0.31 V0.70 V
Current for 100 dB9.8 mA22.0 mA
Highest source impedance
that leaves them alone (one-eighth rule)
4.00 Ω4.00 Ω
Sources that reach 100 dB
out of 280
280278

Where the two part company

2 of the 280 sources have the power for the FT3 (32Ω) but not for the JT1 — Apple USB-C dongle (EU), Steinberg UR22C.

278 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.

What each one needs from 80 to 105 dB

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 JT1 is more demanding than 93% of the 567 non-electrostatic models in this database; the FT3 (32Ω) than 76%. 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 SPLFT3 (32Ω) powerFT3 (32Ω) voltageJT1 powerJT1 voltage
800.03 mW31 mV0.15 mW70 mV
850.10 mW56 mV0.49 mW0.13 V
900.31 mW99 mV1.5 mW0.22 V
950.98 mW0.18 V4.9 mW0.40 V
1003.1 mW0.31 V15 mW0.70 V
1059.8 mW0.56 V49 mW1.25 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.

The cheapest source that satisfies both

SourcePriceHeadroom, FT3 (32Ω)Headroom, JT1Output impedanceNoise
JadeAudio JA11$209.9 dB2.9 dB0.5 Ω1.7 µV
FiiO KA11$2918.1 dB11.1 dB0.7 Ω1.7 µV
FiiO BTR11$369.9 dB2.9 dB0.5 Ω8.0 µV

Of the 280 sources here, 278 reach 100 dB on both. That is the easy axis. 70 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 206 of them are in the second group.

The cheapest of the 70 is the JadeAudio JA11, at $20. It leaves 9.9 dB of headroom on the FT3 (32Ω) 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 25 dB and 32 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.

What each sheet prints, and what it is worth

ModelAs printedToleranceStandard
FT3 (32Ω)nothing printed——
JT115Hz-30KHznot printednot printed

FiiO prints nothing at all for the FT3 (32Ω). 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.

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 JT1 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.

Both pages in full

Each model has a page of its own with the full source list, the hiss estimate and the provenance of every figure above: FiiO FT3 (32Ω) 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.

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