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 RA280 has more power - 250W against 130W into 8 ohms. That is about 2.8dB, so it plays usefully louder before it runs out and has more in hand on peaks. |
| Grip on hard loads | B | Arcam SA30 holds up better into a 4-ohm load: its output increases strongly to 200W, where the other barely increases. That matters with demanding speakers far more than the 8-ohm figure does. |
| Noise floor | B | Arcam SA30 is the quieter design on paper - 112dB against 109dB. Audible mainly with sensitive speakers in a quiet room. |
| Built-in DAC | B | Arcam SA30 has a DAC on board; the other needs an external one, which is another box, another power lead and another purchase. |
| Streaming | B | Only Arcam SA30 has AirPlay 2 and Roon. |
| Room to grow | B | Only Arcam SA30 offers preamp outputs - which decides whether you can add a subwoofer or a power amplifier later without replacing the box. |
| Headphones | depends | Only Arcam SA30 has a headphone output. Worth something if you listen late, nothing if you never do. |
| Amplifier class | depends | HiFi Rose RA280 is Class AD and Arcam SA30 is Class G. Class G/H switches its supply rails to cut the heat a Class A/B design wastes. Modern examples of both measure well - judge by the rest of the page. |
| Price | evenly matched | Priced within a few per cent of each other. |
| Watts per dollar | A | HiFi Rose RA280 is the cheaper watt - about $14 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 RA280 B Arcam SA30
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?
Arcam SA30 has the edge on paper, though not by much. The rows marked "depends" are more likely to decide this than the score is. If your speakers are a difficult load - 4 ohms nominal, big woofers, or a sensitivity in the low 80s - Arcam SA30 is the safer partner, because how an amplifier behaves when the impedance drops matters more than its 8-ohm rating. Start with the room. In a large or open-plan room, or with speakers that are hard to drive - low sensitivity, or an impedance that dips - HiFi Rose RA280 has the headroom, and headroom is what stops an amplifier hardening up on peaks. At desk distance or in a small room, 130 watts is already more than most people ever use, and the extra 120 watts would be headroom you pay for and never hear.
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.