These are not the same size of amplifier: WiiM Amp Ultra has roughly 2.5x the power of Bluesound POWERNODE Edge. That is about 4dB, so it is a question of room size and how hard your speakers are to drive, not of one being the better amplifier.
| Area | Better | Why |
|---|
| Power | A | WiiM Amp Ultra has more power - 100W against 40W into 8 ohms. That is about 4dB, so it plays usefully louder before it runs out and has more in hand on peaks. |
| Built-in DAC | B | Both decode on board, but only Bluesound POWERNODE Edge handles MQA. |
| Streaming | evenly matched | Only WiiM Amp Ultra has Chromecast; only Bluesound POWERNODE Edge has AirPlay 2 and BluOS. Neither list is longer in a way that matters - check the one service you actually pay for. |
| Room to grow | evenly matched | The same expansion options on both. |
| Price | A | WiiM Amp Ultra costs less - $549 against $649 at list. |
| Watts per dollar | A | WiiM Amp Ultra is the cheaper watt - about $5 per watt against $16. A blunt measure, and it says nothing about how either sounds, but it is the honest one for raw output. |
A WiiM Amp Ultra B Bluesound POWERNODE Edge
depends neither is better in the abstract - it turns on your room, your system or how you will use them. Only specs published for both amplifiers are judged; anything missing on either side is left out rather than guessed.
Which should you choose?
WiiM Amp Ultra has the edge on paper, though not by much. The rows marked "depends" are more likely to decide this than the score is. Start with the room. In a large or open-plan room, or with speakers that are hard to drive - low sensitivity, or an impedance that dips - WiiM Amp Ultra has the headroom, and headroom is what stops an amplifier hardening up on peaks. At desk distance or in a small room, 40 watts is already more than most people ever use, and the extra 60 watts would be headroom you pay for and never hear.
What a spec sheet cannot show: how either sounds with your speakers, how the controls feel day to day, and what the app is like to live with - which is where most all-in-one amplifiers are actually won or lost. Power figures are the manufacturers' own and are not measured to a common standard, so treat small differences as noise. If you can hear both, that will tell you more than any row above.