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 | HiFi Rose RS520 has more power - 250W against 200W into 8 ohms. That is about 1dB, which is a small step in loudness but real headroom on peaks. |
| Grip on hard loads | B | Anthem STR holds up better into a 4-ohm load: its output nearly doubles to 400W, where the other barely increases. That matters with demanding speakers far more than the 8-ohm figure does. |
| Noise floor | B | Anthem STR is the quieter design on paper - 120dB against 109dB. Audible mainly with sensitive speakers in a quiet room. |
| Built-in DAC | A | Both decode on board. HiFi Rose RS520 goes higher - 768kHz against 192kHz. Very few recordings exist above 192kHz, so treat this as headroom, not as sound quality. |
| Streaming | evenly matched | Only HiFi Rose RS520 has Roon. Neither list is longer in a way that matters - check the one service you actually pay for. |
| Analogue inputs | B | Anthem STR takes more analogue sources - 5 against 1. |
| Phono stage | depends | Anthem STR has a built-in phono stage (MM,MC) and HiFi Rose RS520 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 | HiFi Rose RS520 is Class AD and Anthem STR is Class A/B. 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 | HiFi Rose RS520 takes up about 41% less shelf area (1135cm² against 1931cm²), and it is 119mm shallower, which is the measurement that decides whether a rack door shuts. |
| Price | A | HiFi Rose RS520 costs less - $3,695 against $5,000 at list. |
| Watts per dollar | A | HiFi Rose RS520 is the cheaper watt - about $15 per watt against $25. A blunt measure, and it says nothing about how either sounds, but it is the honest one for raw output. |
A HiFi Rose RS520 B Anthem STR
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?
Neither runs away with it - they trade advantages. Let the "depends" rows and the speakers you already own settle it. If your speakers are a difficult load - 4 ohms nominal, big woofers, or a sensitivity in the low 80s - Anthem STR is the safer partner, because how an amplifier behaves when the impedance drops matters more than its 8-ohm rating. If you play records, Anthem STR 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.