These are not the same size of amplifier: NAD Masters Series M33 V2 has roughly 2x the power of Cambridge Audio Edge A. That is about 3dB, 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 | A | NAD Masters Series M33 V2 has more power - 200W against 100W into 8 ohms. That is about 3dB, so it plays usefully louder before it runs out and has more in hand on peaks. |
| Grip on hard loads | evenly matched | Both behave much the same into 4 ohms - output nearly doubles (380W and 200W). |
| Noise floor | A | NAD Masters Series M33 V2 is the quieter design on paper - 120dB against 103dB. Audible mainly with sensitive speakers in a quiet room. |
| Built-in DAC | B | Both decode on board, but only Cambridge Audio Edge A handles DSD. |
| Streaming | A | Only NAD Masters Series M33 V2 has AirPlay 2, Roon and BluOS. |
| Phono stage | depends | NAD Masters Series M33 V2 has a built-in phono stage and Cambridge Audio Edge A 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 Masters Series M33 V2 is Class D and Cambridge Audio Edge A is Class XA. Class D runs cool and draws almost nothing at idle. Modern examples of both measure well - judge by the rest of the page. |
| Price | B | Cambridge Audio Edge A costs less - $6,499 against $7,399 at list. |
| Watts per dollar | A | NAD Masters Series M33 V2 is the cheaper watt - about $37 per watt against $65. A blunt measure, and it says nothing about how either sounds, but it is the honest one for raw output. |
A NAD Masters Series M33 V2 B Cambridge Audio Edge A
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?
NAD Masters Series M33 V2 leads across most of the measured areas for a fairly modest premium, so it is the easier pick if the budget stretches. Cambridge Audio Edge A is the one to take if it does not. 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 - NAD Masters Series M33 V2 has the headroom, and headroom is what stops an amplifier hardening up on peaks. At desk distance or in a small room, 100 watts is already more than most people ever use, and the extra 100 watts would be headroom you pay for and never hear. If you play records, NAD Masters Series M33 V2 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.