No single best amplifier here. What decides it is what you have to drive, what you need to plug in, and how much of the system you want in one box.
| Area | Better | Why |
|---|
| Power | evenly matched | Effectively the same output - 125W against 150W into 8 ohms is under 1dB, which is not an audible difference in loudness. |
| Room size | depends | We rate MOON 330A the better fit for desk or near-field listening, a small room and a mid-size room, and Cambridge Audio Evo 150 for a very large room. Match the amplifier to the room you actually have, not the one you want. |
| Grip on hard loads | A | MOON 330A holds up better into a 4-ohm load: its output nearly doubles to 250W, where the other increases strongly. That matters with demanding speakers far more than the 8-ohm figure does. |
| Built-in DAC | B | Cambridge Audio Evo 150 has a DAC on board; the other needs an external one, which is another box, another power lead and another purchase. |
| Analogue inputs | evenly matched | The same number of line-level inputs (2). |
| Phono stage | depends | Cambridge Audio Evo 150 has a built-in phono stage (MM) and MOON 330A 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. |
| Use with a TV | depends | Only Cambridge Audio Evo 150 has HDMI ARC, so the television can drive it directly and one remote controls the volume. If the system is for music only, this changes nothing. |
| Headphones | depends | Only Cambridge Audio Evo 150 has a headphone output. Worth something if you listen late, nothing if you never do. |
| Amplifier class | depends | MOON 330A is Class A/B and Cambridge Audio Evo 150 is Class D. Class A/B runs warm and is the long-established mainstream choice; Class D runs cool and draws almost nothing at idle. Modern examples of both measure well - judge by the rest of the page. |
| Shelf space | depends | Cambridge Audio Evo 150 takes up about 22% less shelf area (1190cm² against 1527cm²). |
| Price | B | Cambridge Audio Evo 150 costs less - $3,249 against $4,400 at list. |
| Watts per dollar | B | Cambridge Audio Evo 150 is the cheaper watt - about $22 per watt against $35. A blunt measure, and it says nothing about how either sounds, but it is the honest one for raw output. |
A MOON 330A B Cambridge Audio Evo 150
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?
Cambridge Audio Evo 150 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 - MOON 330A is the safer partner, because how an amplifier behaves when the impedance drops matters more than its 8-ohm rating. If you play records, Cambridge Audio Evo 150 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.