Short answer
Both are desktop DAC/amps, $319 against $349.
The Aune X1s GT reaches 100 dB on 565 of the 567 models here, the WiiM Ultra on 562.
| Specification | Aune X1s GT | WiiM Ultra |
|---|---|---|
| Power into 32Ω | 320 mW | 150 mW |
| Power into 150Ω | 68 mW | 22 mW |
| Power into 300Ω | 34 mW | 6.0 mW |
| Power into 600Ω | 17 mW | 3.0 mW |
| Output impedance | not published | not published |
| Output noise | not published | not published |
| Price | $319 | $349 |
| Headphones it reaches 100 dB on out of 567 | 565 | 562 |
Not published means the maker leaves it out, so that axis cannot be compared.
| Balanced | Aune X1s GT | WiiM Ultra |
|---|---|---|
| Socket | 4.4mm | no separate rating |
| Power into 32Ω | 1.2 W | — |
| Power into 300Ω | 128 mW derived | — |
| Output impedance | not published | — |
| Output noise | not published | — |
| Headphones it reaches 100 dB on out of 567 | 567 | — |
Only the Aune X1s GT has a separate balanced rating from its maker; through it, it reaches 100 dB on 567 of the 567 models here. The WiiM Ultra may still have a balanced socket — its spec sheet simply gives no figure for one, so there is nothing to put beside it. Derived figures are worked out from the loads the maker did publish.
| Load | Aune X1s GT | WiiM Ultra |
|---|---|---|
| 32 Ω | Published | Published |
| 150 Ω | Derived | Derived |
| 300 Ω | Derived | Published |
| 600 Ω | Derived | Derived |
Both makers publish a power rating. Aune X1s GT publishes at 32 Ω; WiiM Ultra at 32 Ω and at 300 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 WiiM Ultra figure is the maker’s own. On those rows the derived number is the one to doubt first.
3 headphones reach 100 dB on the Aune X1s GT but not on the WiiM Ultra — Sennheiser HD 600, Symphonium Crimson, Symphonium Helios.
562 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 Audio-Technica ATH-R70X: Aune X1s GT has +11 dB of headroom there against +4 dB. 8 dB is about 5.7 times the power, which matters for peaks rather than for how loud the music sits.
The hiss columns are empty for Aune X1s GT and WiiM Ultra because neither maker publishes no output noise figure.
| Headphone | Impedance | Needs | Aune X1s GT headroom | WiiM Ultra headroom | Aune X1s GT hiss | WiiM Ultra hiss |
|---|---|---|---|---|---|---|
| Shure SE846 | 9 Ω | 0.04 mW | +34 dB | +30 dB | not published | not published |
| Campfire Audio Andromeda 2020 | 9 Ω | 4.0 mW | +14 dB | +10 dB | not published | not published |
| Audeze LCD-2 Classic | 70 Ω | 0.79 mW | +23 dB | +19 dB | not published | not published |
| Beyerdynamic DT 1990 Pro (250Ω) | 250 Ω | 0.63 mW | +18 dB | +12 dB | not published | not published |
| HiFiMAN HE400se | 25 Ω | 7.9 mW | +15 dB | +12 dB | not published | not published |
| Audio-Technica ATH-R70X | 470 Ω | 1.6 mW | +11 dB | +4 dB | not published | not published |
| Sennheiser HD 600 | 300 Ω | 6.6 mW | +7 dB | -0 dB | not published | not published |
| HiFiMAN Susvara | 60 Ω | 50 mW | +5 dB | +2 dB | not published | not published |
The WiiM Ultra costs $30 more than the Aune X1s GT, and on these three axes the money buys nothing: among the 567 models here there is not one that the WiiM Ultra handles and the Aune X1s GT does not — not on power, not on the one-eighth rule, not on hiss. The traffic runs the other way: the cheaper Aune X1s GT drives 3 models to 100 dB that the WiiM Ultra does not.
Only published figures count here; blank axes are counted separately.
Each in full: Aune X1s GT and WiiM Ultra.