Both are desktop DAC/amps, $319 against $349. 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 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 |
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.
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. That is a power count and nothing more; whether either source suits a given headphone also depends on the two lines above.
Each has a page of its own with every power figure traced to what the maker published and a full headphone list: Aune X1s GT and WiiM Ultra. Or put either against your own headphones in the source comparison tool.