Short answer
Both are dongles, $29 against $40.
The FiiO KA11 reaches 100 dB on 566 of the 567 models here, the Tanchjim Stargate II on 561.
| Specification | FiiO KA11 | Tanchjim Stargate II |
|---|---|---|
| Power into 32Ω | 200 mW | 75 mW |
| Power into 150Ω | 43 mW | 16 mW |
| Power into 300Ω | 22 mW | 8.0 mW |
| Power into 600Ω | 11 mW | 4.0 mW |
| Output impedance | 0.7 Ω | not published |
| Output noise | 1.7 µV | not published |
| Price | $29 | $40 |
| Headphones it reaches 100 dB on out of 567 | 566 | 561 |
Not published means the maker leaves it out, so that axis cannot be compared.
| Load | FiiO KA11 | Tanchjim Stargate II |
|---|---|---|
| 32 Ω | Published | Published |
| 150 Ω | Derived | Derived |
| 300 Ω | Published | Derived |
| 600 Ω | Derived | Derived |
Both makers publish a power rating. FiiO KA11 publishes at 32 Ω and at 300 Ω; Tanchjim Stargate II at 32 Ω. The other rows are worked out from those.
So the two columns are not equally firm row by row: at 300 Ω only the FiiO KA11 figure is the maker’s own. On those rows the derived number is the one to doubt first.
5 headphones reach 100 dB on the FiiO KA11 but not on the Tanchjim Stargate II — HiFiMAN Susvara, Moondrop PARA, Moondrop SKYLAND, 2 more.
561 of the 567 models here reach 100 dB on both.
Headroom is at a 100 dB SPL peak.
The widest gap on the list is the Campfire Audio Andromeda 2020: FiiO KA11 has +15 dB of headroom there against +11 dB. 5 dB is about 3 times the power, which matters for peaks rather than for how loud the music sits.
The hiss columns are empty for Tanchjim Stargate II because that maker publishes no output noise figure.
| Headphone | Impedance | Needs | FiiO KA11 headroom | Tanchjim Stargate II headroom | FiiO KA11 hiss | Tanchjim Stargate II hiss |
|---|---|---|---|---|---|---|
| Shure SE846 | 9 Ω | 0.04 mW | +35 dB | +31 dB | 19 dB | not published |
| Campfire Audio Andromeda 2020 | 9 Ω | 4.0 mW | +15 dB | +11 dB | -1 dB | not published |
| Audeze LCD-2 Classic | 70 Ω | 0.79 mW | +21 dB | +16 dB | -3 dB | not published |
| Beyerdynamic DT 1990 Pro (250Ω) | 250 Ω | 0.63 mW | +16 dB | +12 dB | -7 dB | not published |
| HiFiMAN HE400se | 25 Ω | 7.9 mW | +14 dB | +10 dB | -8 dB | not published |
| Audio-Technica ATH-R70X | 470 Ω | 1.6 mW | +9 dB | +5 dB | -14 dB | not published |
| Sennheiser HD 600 | 300 Ω | 6.6 mW | +5 dB | +1 dB | -18 dB | not published |
| HiFiMAN Susvara | 60 Ω | 50 mW | +3 dB | -1 dB | -20 dB | not published |
The Tanchjim Stargate II costs $11 more than the FiiO KA11, and on these three axes the money buys nothing: among the 567 models here there is not one that the Tanchjim Stargate II handles and the FiiO KA11 does not — not on power, not on the one-eighth rule, not on hiss. The traffic runs the other way: the cheaper FiiO KA11 drives 5 models to 100 dB that the Tanchjim Stargate II does not.
Only published figures count here; blank axes are counted separately.
Each in full: FiiO KA11 and Tanchjim Stargate II.