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 - 55W against 60W into 8 ohms is under 1dB, which is not an audible difference in loudness. |
| Grip on hard loads | A | Yamaha WXA-70A holds up better into a 4-ohm load: its output nearly doubles to 105W, where the other barely increases. That matters with demanding speakers far more than the 8-ohm figure does. |
| Built-in DAC | A | Both decode on board, but only Yamaha WXA-70A handles DSD. |
| Streaming | A | Only Yamaha WXA-70A has AirPlay 2, Chromecast and Roon. |
| Analogue inputs | B | Yamaha A-S301 takes more analogue sources - 6 against 1. |
| Phono stage | depends | Yamaha A-S301 has a built-in phono stage (MM) and Yamaha WXA-70A 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. |
| Headphones | depends | Only Yamaha A-S301 has a headphone output. Worth something if you listen late, nothing if you never do. |
| Shelf space | depends | Yamaha WXA-70A takes up about 65% less shelf area (587cm² against 1701cm²), and it is 124mm shallower, which is the measurement that decides whether a rack door shuts. |
| Price | B | Yamaha A-S301 costs less - $350 against $1,300 at list. |
| Watts per dollar | B | Yamaha A-S301 is the cheaper watt - about $6 per watt against $24. A blunt measure, and it says nothing about how either sounds, but it is the honest one for raw output. |
A Yamaha WXA-70A 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?
Yamaha WXA-70A is ahead, but on only 1 of the measured areas, and it costs about 3.7x the price. That is a lot of money for a narrow margin - Yamaha A-S301 is the sensible buy unless a specific feature above decides it for you. If your speakers are a difficult load - 4 ohms nominal, big woofers, or a sensitivity in the low 80s - Yamaha WXA-70A 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.