Both are desktop DAC/amps, $199 against $229. This page puts them side by side on the only three things a maker can be held to — power, output impedance and noise — and then asks the question that actually matters: which headphones do they treat differently?
The FiiO K7 reaches 100 dB on 567 of the 567 models here, the iFi Zen DAC 3 on 564.
| Specification | FiiO K7 | iFi Zen DAC 3 |
|---|---|---|
| Power into 32Ω | 1.2 W | 210 mW |
| Power into 150Ω | 269 mW | 50 mW |
| Power into 300Ω | 140 mW | 28 mW |
| Power into 600Ω | 70 mW | 18 mW |
| Output impedance | 1.0 Ω | 1 Ω |
| Output noise | 3.1 µV | not published |
| Price | $199 | $229 |
| Headphones it reaches 100 dB on out of 567 | 567 | 564 |
A figure marked not published is missing from the maker’s own material, which is not the same as being good or bad. Where one of these two publishes a number and the other does not, the comparison on that axis cannot be made at all — and saying so is more useful than guessing.
| Load | FiiO K7 | iFi Zen DAC 3 |
|---|---|---|
| 32 Ω | Published | Published |
| 150 Ω | Derived | Derived |
| 300 Ω | Published | Derived |
| 600 Ω | Derived | Published |
Both makers publish a power rating, which is less common than the table above makes it look: of the 280 sources here, 209 publish a figure at at least one load and only 2 publish one at all four. FiiO K7 publishes at 32 Ω and at 300 Ω; iFi Zen DAC 3 at 32 Ω and at 600 Ω. Every other row is worked out from those — between two published loads, or beyond them holding voltage constant, which understates rather than flatters.
So the two columns are not equally firm row by row: at 300 Ω only the FiiO K7 figure is the maker’s own and at 600 Ω only the iFi Zen DAC 3 figure is the maker’s own. On those rows the derived number is the one to doubt first.
What each of these labels means, and why a derived figure is still worth printing, is set out in how this data was built.
3 headphones reach 100 dB on the FiiO K7 but not on the iFi Zen DAC 3 — Moondrop PARA, Symphonium Crimson, Symphonium Titan.
564 of the 567 models here reach 100 dB on both. That is a power count and nothing more; whether either source suits a given headphone also depends on the two lines above.
The counts above say how many models the two treat differently. This says by how much. The same 8 headphones appear on every page of this kind, ordered from the easiest to drive to the hardest, so a row can be read across pages as well as across columns. Headroom is at a 100 dB SPL peak.
The widest gap on the list is the Shure SE846: FiiO K7 has +39 dB of headroom there against +32 dB. 8 dB is about 5.8 times the power, which matters for peaks rather than for how loud the music sits.
The hiss columns are empty for iFi Zen DAC 3 because that maker publishes no output noise figure. That is a gap in the specification, not a quiet amplifier, and it is left blank here rather than filled with a plausible number.
| Headphone | Impedance | Needs | FiiO K7 headroom | iFi Zen DAC 3 headroom | FiiO K7 hiss | iFi Zen DAC 3 hiss |
|---|---|---|---|---|---|---|
| Shure SE846 | 9 Ω | 0.04 mW | +39 dB | +32 dB | 24 dB | not published |
| Campfire Audio Andromeda 2020 | 9 Ω | 4.0 mW | +19 dB | +12 dB | 4 dB | not published |
| Audeze LCD-2 Classic | 70 Ω | 0.79 mW | +29 dB | +21 dB | 2 dB | not published |
| Beyerdynamic DT 1990 Pro (250Ω) | 250 Ω | 0.63 mW | +24 dB | +17 dB | -2 dB | not published |
| HiFiMAN HE400se | 25 Ω | 7.9 mW | +21 dB | +13 dB | -3 dB | not published |
| Audio-Technica ATH-R70X | 470 Ω | 1.6 mW | +18 dB | +11 dB | -9 dB | not published |
| Sennheiser HD 600 | 300 Ω | 6.6 mW | +13 dB | +6 dB | -13 dB | not published |
| HiFiMAN Susvara | 60 Ω | 50 mW | +11 dB | +4 dB | -15 dB | not published |
The iFi Zen DAC 3 costs $30 more than the FiiO K7, and on these three axes the money buys nothing: among the 567 models here there is not one that the iFi Zen DAC 3 handles and the FiiO K7 does not — not on power, not on the one-eighth rule, not on hiss. The traffic runs the other way: the cheaper FiiO K7 drives 3 models to 100 dB that the iFi Zen DAC 3 does not.
Everything in this paragraph counts only figures the two makers published. An advantage on an axis one of them leaves blank cannot be counted, and is not counted — how often that happens is its own page.
Each has a page of its own with every power figure traced to what the maker published and a full headphone list: FiiO K7 and iFi Zen DAC 3. Or put either against your own headphones in the source comparison tool.