One is a streaming all-in-one and the other is an amplifier. Judge them on how many boxes you want and what you already own, not on the spec sheet alone.
| Area | Better | Why |
|---|
| Power | evenly matched | Effectively the same output - 60W against 60W into 8 ohms is under 1dB, which is not an audible difference in loudness. |
| Grip on hard loads | A | WiiM Amp Pro holds up better into a 4-ohm load: its output nearly doubles to 120W, where the other barely increases. That matters with demanding speakers far more than the 8-ohm figure does. |
| Noise floor | A | WiiM Amp Pro is the quieter design on paper - 105dB against 99dB. Audible mainly with sensitive speakers in a quiet room. |
| Built-in DAC | evenly matched | Both have a DAC on board with much the same capability. |
| Streaming | A | Only WiiM Amp Pro has Chromecast and Roon. |
| Phono stage | depends | Yamaha A-S301 has a built-in phono stage (MM) and WiiM Amp Pro does not. Decisive if you own a turntable, completely irrelevant if you do not - and an outboard phono stage is easy to add later either way. |
| Room to grow | evenly matched | The same expansion options on both. |
| Amplifier class | depends | WiiM Amp Pro is Class D and Yamaha A-S301 is Class A/B. Class D runs cool and draws almost nothing at idle; Class A/B runs warm and is the long-established mainstream choice. Modern examples of both measure well - judge by the rest of the page. |
| Shelf space | depends | WiiM Amp Pro takes up about 75% less shelf area (420cm² against 1701cm²), and it is 171mm shallower, which is the measurement that decides whether a rack door shuts. |
| Price | B | Yamaha A-S301 costs less - $350 against $379 at list. |
A WiiM Amp Pro B Yamaha A-S301
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 Pro leads across most of the measured areas for a fairly modest premium, so it is the easier pick if the budget stretches. Yamaha A-S301 is the one to take if it does not. If your speakers are a difficult load - 4 ohms nominal, big woofers, or a sensitivity in the low 80s - WiiM Amp Pro is the safer partner, because how an amplifier behaves when the impedance drops matters more than its 8-ohm rating. If you play records, Yamaha A-S301 saves you buying a phono stage; if you do not, ignore that row entirely.
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.