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 | B | Rotel RAS-5000 has more power - 140W against 100W into 8 ohms. That is about 1.5dB, which is a small step in loudness but real headroom on peaks. |
| Room size | depends | We rate NAD Masters Series M10 V2 the better fit for desk or near-field listening, a small room and a mid-size room, and Rotel RAS-5000 for a very large room. Match the amplifier to the room you actually have, not the one you want. |
| Grip on hard loads | B | Rotel RAS-5000 holds up better into a 4-ohm load: its output increases strongly to 220W, where the other barely increases. That matters with demanding speakers far more than the 8-ohm figure does. |
| Noise floor | B | Rotel RAS-5000 is the quieter design on paper - 103dB against 90dB. Audible mainly with sensitive speakers in a quiet room. |
| Built-in DAC | B | Both decode on board. Rotel RAS-5000 goes higher - 384kHz against 192kHz. Very few recordings exist above 192kHz, so treat this as headroom, not as sound quality. |
| Streaming | evenly matched | Only NAD Masters Series M10 V2 has BluOS; only Rotel RAS-5000 has Chromecast. Neither list is longer in a way that matters - check the one service you actually pay for. |
| Analogue inputs | A | NAD Masters Series M10 V2 takes more analogue sources - 2 against 1. |
| Room to grow | evenly matched | The same expansion options on both. |
| Headphones | depends | Only Rotel RAS-5000 has a headphone output. Worth something if you listen late, nothing if you never do. |
| Amplifier class | depends | NAD Masters Series M10 V2 is Class D and Rotel RAS-5000 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 | NAD Masters Series M10 V2 takes up about 69% less shelf area (606cm² against 1940cm²), and it is 169mm shallower, which is the measurement that decides whether a rack door shuts. |
| Price | evenly matched | Priced within a few per cent of each other. |
| Watts per dollar | B | Rotel RAS-5000 is the cheaper watt - about $21 per watt against $30. A blunt measure, and it says nothing about how either sounds, but it is the honest one for raw output. |
A NAD Masters Series M10 V2 B Rotel RAS-5000
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?
Rotel RAS-5000 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 - Rotel RAS-5000 is the safer partner, because how an amplifier behaves when the impedance drops matters more than its 8-ohm rating.
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.