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 | B | SVS Prime SoundBase has more power - 75W against 55W into 8 ohms. That is about 1.3dB, which is a small step in loudness but real headroom on peaks. |
| Room size | depends | We rate Yamaha WXA-50 the better fit for desk or near-field listening and a small room, and SVS Prime SoundBase for a mid-size room, a large room and a very large room. Match the amplifier to the room you actually have, not the one you want. |
| Grip on hard loads | evenly matched | Both behave much the same into 4 ohms - output nearly doubles (105W and 150W). |
| Noise floor | A | Yamaha WXA-50 is the quieter design on paper - 110dB against 90dB. Audible mainly with sensitive speakers in a quiet room. |
| Built-in DAC | A | Both decode on board, but only Yamaha WXA-50 handles DSD. |
| Streaming | B | Only SVS Prime SoundBase has AirPlay 2, Chromecast and DTS Play-Fi. |
| Analogue inputs | B | SVS Prime SoundBase takes more analogue sources - 2 against 1. |
| Use with a TV | depends | Only SVS Prime SoundBase has HDMI ARC/eARC, so the television can drive it directly and one remote controls the volume. If the system is for music only, this changes nothing. |
| Room to grow | evenly matched | The same expansion options on both. |
| Headphones | depends | Only SVS Prime SoundBase has a headphone output. Worth something if you listen late, nothing if you never do. |
| Price | A | Yamaha WXA-50 costs less - $599 against $699 at list. |
A Yamaha WXA-50 B SVS Prime SoundBase
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?
The usual trade-off: SVS Prime SoundBase measures better, Yamaha WXA-50 costs about 14% less. With most speakers in most rooms that gap is smaller in practice than it looks here. If this sits under a television, SVS Prime SoundBase is the one to buy - HDMI ARC means the TV remote controls the volume and there is no second box in the way.
What a spec sheet cannot show: how either sounds with your speakers, how the interface feels 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.