One is a streaming all-in-one and the other is an amplifier. Judge them on how many boxes you want and what you already own, not on the spec sheet alone.
| Area | Better | Why |
|---|
| Power | evenly matched | Effectively the same output - 90W against 100W into 8 ohms is under 1dB, which is not an audible difference in loudness. |
| Room size | depends | We rate Yamaha A-S1200 the better fit for a small room, and NAD Masters Series M10 V2 for a large room and a very large room. Match the amplifier to the room you actually have, not the one you want. |
| Grip on hard loads | A | Yamaha A-S1200 holds up better into a 4-ohm load: its output increases strongly to 150W, where the other barely increases. That matters with demanding speakers far more than the 8-ohm figure does. |
| Noise floor | A | Yamaha A-S1200 is the quieter design on paper - 110dB against 90dB. Audible mainly with sensitive speakers in a quiet room. |
| Built-in DAC | B | NAD Masters Series M10 V2 has a DAC on board; the other needs an external one, which is another box, another power lead and another purchase. |
| Streaming | B | Only NAD Masters Series M10 V2 has AirPlay 2, Roon and BluOS. |
| Analogue inputs | A | Yamaha A-S1200 takes more analogue sources - 6 against 2. |
| Phono stage | depends | Yamaha A-S1200 has a built-in phono stage (MM,MC) and NAD Masters Series M10 V2 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. |
| Headphones | depends | Only Yamaha A-S1200 has a headphone output. Worth something if you listen late, nothing if you never do. |
| Amplifier class | depends | Yamaha A-S1200 is Class A/B and NAD Masters Series M10 V2 is Class D. Class A/B runs warm and is the long-established mainstream choice; Class D runs cool and draws almost nothing at idle. Modern examples of both measure well - judge by the rest of the page. |
| Shelf space | depends | NAD Masters Series M10 V2 takes up about 71% less shelf area (606cm² against 2123cm²), and it is 210mm shallower, which is the measurement that decides whether a rack door shuts. |
| Price | evenly matched | Priced within a few per cent of each other. |
A Yamaha A-S1200 B NAD Masters Series M10 V2
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?
Yamaha A-S1200 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 - Yamaha A-S1200 is the safer partner, because how an amplifier behaves when the impedance drops matters more than its 8-ohm rating. If you play records, Yamaha A-S1200 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.