Both are NAD, from different ranges - the engineering approach is shared and the differences are mostly in power, connectivity and price.
| Area | Better | Why |
|---|
| Power | A | NAD M10 V3 has more power - 100W against 80W into 8 ohms. That is about 1dB, which is a small step in loudness but real headroom on peaks. |
| Grip on hard loads | evenly matched | Both behave much the same into 4 ohms - output barely increases (100W and 80W). |
| Noise floor | A | NAD M10 V3 is the quieter design on paper - 90dB against 84dB. Audible mainly with sensitive speakers in a quiet room. |
| Built-in DAC | evenly matched | Both have a DAC on board with much the same capability. |
| Streaming | evenly matched | The same streaming platforms and services on both. |
| Phono stage | depends | NAD M10 V3 has a built-in phono stage and NAD C 700 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. |
| Price | B | NAD C 700 costs less - $1,599 against $2,499 at list. |
| Watts per dollar | B | NAD C 700 is the cheaper watt - about $20 per watt against $25. A blunt measure, and it says nothing about how either sounds, but it is the honest one for raw output. |
A NAD M10 V3 B NAD C 700
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 M10 V3 is ahead, but on only 1 of the measured areas, and it costs about 56% more. That is a lot of money for a narrow margin - NAD C 700 is the sensible buy unless a specific feature above decides it for you. If you play records, NAD M10 V3 saves you buying a phono stage; if you do not, ignore that row entirely. Think about the whole system: the roughly $900 saved by taking the cheaper one would buy better speakers or a subwoofer, which does more for the sound than the difference between two competent amplifiers.
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.