These are not the same size of amplifier: Arcam SA30 has roughly 2.6x the power of Arcam A5+. That is about 4.1dB, so it is a question of room size and how hard your speakers are to drive, not of one being the better amplifier.
| Area | Better | Why |
|---|
| Power | B | Arcam SA30 has more power - 130W against 50W into 8 ohms. That is about 4.1dB, so it plays usefully louder before it runs out and has more in hand on peaks. |
| Room size | depends | We rate Arcam A5+ the better fit for desk or near-field listening and a small room, and Arcam SA30 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 increases strongly (75W and 200W). |
| Noise floor | B | Arcam SA30 is the quieter design on paper - 112dB against 106dB. Audible mainly with sensitive speakers in a quiet room. |
| Built-in DAC | B | Both decode on board, but only Arcam SA30 handles MQA. |
| Streaming | B | Only Arcam SA30 has AirPlay 2, Chromecast and Roon. |
| Analogue inputs | B | Arcam SA30 takes more analogue sources - 4 against 3. |
| Use with a TV | depends | Only Arcam SA30 has HDMI 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. |
| Amplifier class | depends | Arcam A5+ is Class A/B and Arcam SA30 is Class G. Class A/B runs warm and is the long-established mainstream choice; 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 | A | Arcam A5+ costs less - $1,200 against $3,300 at list. |
A Arcam A5+ 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?
The usual trade-off: Arcam SA30 measures better, Arcam A5+ costs about 64% less. With most speakers in most rooms that gap is smaller in practice than it looks here. 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 - Arcam SA30 has the headroom, and headroom is what stops an amplifier hardening up on peaks. At desk distance or in a small room, 50 watts is already more than most people ever use, and the extra 80 watts would be headroom you pay for and never hear - we rate Arcam SA30 poorly for near-field use for exactly that reason. If this sits under a television, Arcam SA30 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 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.