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 | A | SVS Prime SoundBase has more power - 75W against 60W into 8 ohms. That is about 1dB, which is a small step in loudness but real headroom on peaks. |
| Room size | depends | We rate SVS Prime SoundBase the better fit for a mid-size room, a large room and a very large room, and OSD Nero Stream XD2 for desk or near-field listening and a small 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 (150W and 120W). |
| Noise floor | B | OSD Nero Stream XD2 is the quieter design on paper - 95dB against 90dB. 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 SVS Prime SoundBase has AirPlay 2, Chromecast and DTS Play-Fi. |
| Analogue inputs | A | SVS Prime SoundBase takes more analogue sources - 2 against 1. |
| Room to grow | evenly matched | The same expansion options on both. |
| Shelf space | depends | SVS Prime SoundBase takes up about 25% less shelf area (517cm² against 688cm²), and it is 57mm shallower, which is the measurement that decides whether a rack door shuts. |
| Price | B | OSD Nero Stream XD2 costs less - $400 against $699 at list. |
| Watts per dollar | B | OSD Nero Stream XD2 is the cheaper watt - about $7 per watt against $9. A blunt measure, and it says nothing about how either sounds, but it is the honest one for raw output. |
A SVS Prime SoundBase B OSD Nero Stream XD2
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?
SVS Prime SoundBase is ahead, but on only 1 of the measured areas, and it costs about 75% more. That is a lot of money for a narrow margin - OSD Nero Stream XD2 is the sensible buy unless a specific feature above decides it for you. Think about the whole system: the roughly $299 saved by taking the cheaper one would buy better speakers or a subwoofer, which does more for the sound than the difference between two competent amplifiers.
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.