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 | NAD C 368 has more power - 80W against 60W into 8 ohms. That is about 1.2dB, which is a small step in loudness but real headroom on peaks. |
| Room size | depends | We rate NAD C 368 the better fit for a mid-size room, a large room and a very large room, and Cambridge Audio CXA61 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 | B | Cambridge Audio CXA61 holds up better into a 4-ohm load: its output increases strongly to 90W, where the other barely increases. That matters with demanding speakers far more than the 8-ohm figure does. |
| Noise floor | B | Cambridge Audio CXA61 is the quieter design on paper - 105dB against 98dB. Audible mainly with sensitive speakers in a quiet room. |
| Built-in DAC | B | Both decode on board, but only Cambridge Audio CXA61 handles DSD. |
| Analogue inputs | B | Cambridge Audio CXA61 takes more analogue sources - 5 against 2. |
| Phono stage | depends | NAD C 368 has a built-in phono stage (MM) and Cambridge Audio CXA61 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 | NAD C 368 is Class D and Cambridge Audio CXA61 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 CXA61 takes up about 13% less shelf area (1595cm² against 1840cm²), and it is 53mm shallower, which is the measurement that decides whether a rack door shuts. |
| Price | B | Cambridge Audio CXA61 costs less - $1,099 against $1,199 at list. |
A NAD C 368 B Cambridge Audio CXA61
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 CXA61 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 - Cambridge Audio CXA61 is the safer partner, because how an amplifier behaves when the impedance drops matters more than its 8-ohm rating. If you play records, NAD C 368 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.