Short answer
Both are desktop DAC/amps, $349 against $449.
The xDuoo XA-10 reaches 100 dB on 567 of the 567 models here, the WiiM Ultra on 562.
| Specification | WiiM Ultra | xDuoo XA-10 |
|---|---|---|
| Power into 32Ω | 150 mW | 3.0 W |
| Power into 150Ω | 22 mW | 640 mW |
| Power into 300Ω | 6.0 mW | 320 mW |
| Power into 600Ω | 3.0 mW | 160 mW |
| Output impedance | not published | not published |
| Output noise | not published | not published |
| Price | $349 | $449 |
| Headphones it reaches 100 dB on out of 567 | 562 | 567 |
Not published means the maker leaves it out, so that axis cannot be compared.
| Balanced | WiiM Ultra | xDuoo XA-10 |
|---|---|---|
| Socket | no separate rating | 4.4mm |
| Power into 32Ω | — | 4.0 W |
| Power into 300Ω | — | 427 mW derived |
| Output impedance | — | not published |
| Output noise | — | not published |
| Headphones it reaches 100 dB on out of 567 | — | 567 |
Only the xDuoo XA-10 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 | WiiM Ultra | xDuoo XA-10 |
|---|---|---|
| 32 Ω | Published | Published |
| 150 Ω | Derived | Derived |
| 300 Ω | Published | Derived |
| 600 Ω | Derived | Derived |
Both makers publish a power rating. WiiM Ultra publishes at 32 Ω and at 300 Ω; xDuoo XA-10 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 WiiM Ultra 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 xDuoo XA-10 but not on the WiiM Ultra — Moondrop PARA, Sennheiser HD 600, Symphonium Crimson, 2 more.
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 Sennheiser HD 600: xDuoo XA-10 has +17 dB of headroom there against -0 dB. 17 dB is about 53 times the power, which matters for peaks rather than for how loud the music sits.
The hiss columns are empty for WiiM Ultra and xDuoo XA-10 because neither maker publishes no output noise figure.
| Headphone | Impedance | Needs | WiiM Ultra headroom | xDuoo XA-10 headroom | WiiM Ultra hiss | xDuoo XA-10 hiss |
|---|---|---|---|---|---|---|
| Shure SE846 | 9 Ω | 0.04 mW | +30 dB | +43 dB | not published | not published |
| Campfire Audio Andromeda 2020 | 9 Ω | 4.0 mW | +10 dB | +23 dB | not published | not published |
| Audeze LCD-2 Classic | 70 Ω | 0.79 mW | +19 dB | +32 dB | not published | not published |
| Beyerdynamic DT 1990 Pro (250Ω) | 250 Ω | 0.63 mW | +12 dB | +28 dB | not published | not published |
| HiFiMAN HE400se | 25 Ω | 7.9 mW | +12 dB | +25 dB | not published | not published |
| Audio-Technica ATH-R70X | 470 Ω | 1.6 mW | +4 dB | +21 dB | not published | not published |
| Sennheiser HD 600 | 300 Ω | 6.6 mW | -0 dB | +17 dB | not published | not published |
| HiFiMAN Susvara | 60 Ω | 50 mW | +2 dB | +15 dB | not published | not published |
The xDuoo XA-10 costs $100 more than the WiiM Ultra. Out of the 567 models here, that difference buys 5 more models driven to 100 dB.
Nothing runs the other way: there is no axis here on which the cheaper of the two does better.
Only published figures count here; blank axes are counted separately.
Each in full: WiiM Ultra and xDuoo XA-10.