Two versions of the same amplifier rather than two different designs, so the question is not which is better built but which set of features you actually need - and what the difference costs.
| Area | Better | Why |
|---|
| Power | evenly matched | Effectively the same output - 80W against 80W into 8 ohms is under 1dB, which is not an audible difference in loudness. |
| Grip on hard loads | evenly matched | Both behave much the same into 4 ohms - output barely increases (80W and 80W). |
| Noise floor | evenly matched | Much the same signal-to-noise ratio (84dB vs 84dB). |
| Built-in DAC | A | Both decode on board. NAD C 700 V2 goes higher - 384kHz against 192kHz. Very few recordings exist above 192kHz, so treat this as headroom, not as sound quality. |
| Streaming | evenly matched | The same streaming platforms and services on both. |
| Phono stage | depends | NAD C 700 V2 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 | evenly matched | Priced within a few per cent of each other. |
A NAD C 700 V2 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 C 700 V2 has the edge on paper, though not by much. The rows marked "depends" are more likely to decide this than the score is. If you play records, NAD C 700 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.