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 | A | Cambridge Audio Evo 75 has more power - 75W against 50W into 8 ohms. That is about 1.8dB, which is a small step in loudness but real headroom on peaks. |
| Room size | depends | We rate Cambridge Audio Evo 75 the better fit for a mid-size room, a large room and a very large room, and Audiolab Omnia 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 | A | Cambridge Audio Evo 75 holds up better into a 4-ohm load: its output nearly doubles to 150W, where the other increases strongly. That matters with demanding speakers far more than the 8-ohm figure does. |
| Built-in DAC | B | Both decode on board. Audiolab Omnia goes higher - 768kHz against 384kHz. Very few recordings exist above 192kHz, so treat this as headroom, not as sound quality. |
| Streaming | evenly matched | Only Cambridge Audio Evo 75 has AirPlay 2 and Chromecast; only Audiolab Omnia has DTS Play-Fi. Neither list is longer in a way that matters - check the one service you actually pay for. |
| Analogue inputs | B | Audiolab Omnia takes more analogue sources - 4 against 1. |
| Phono stage | depends | Audiolab Omnia has a built-in phono stage (MM) and Cambridge Audio Evo 75 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 | B | Only Audiolab Omnia offers a pre-out/main-in loop - which decides whether you can add a subwoofer or a power amplifier later without replacing the box. |
| Built-in sources | depends | Audiolab Omnia has a CD player built in. That is one less box if you still play discs or listen to radio, and dead weight if you do not. |
| Amplifier class | depends | Cambridge Audio Evo 75 is Class D and Audiolab Omnia is Class A/B. Class D runs cool and draws almost nothing at idle; 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 | Cambridge Audio Evo 75 takes up about 25% less shelf area (1190cm² against 1582cm²). |
| Price | B | Audiolab Omnia costs less - $2,300 against $2,499 at list. |
| Watts per dollar | A | Cambridge Audio Evo 75 is the cheaper watt - about $33 per watt against $46. A blunt measure, and it says nothing about how either sounds, but it is the honest one for raw output. |
A Cambridge Audio Evo 75 B Audiolab Omnia
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 - Cambridge Audio Evo 75 is the safer partner, because how an amplifier behaves when the impedance drops matters more than its 8-ohm rating. If you play records, Audiolab Omnia 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 interface feels 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.