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 | NAD C 3050 has more power - 100W against 72W into 8 ohms. That is about 1.4dB, which is a small step in loudness but real headroom on peaks. |
| Built-in DAC | B | Both decode on board. NAD C 3050 goes higher - 384kHz against 192kHz. Very few recordings exist above 192kHz, so treat this as headroom, not as sound quality. |
| Use with a TV | depends | Only NAD C 3050 has HDMI, so the television can drive it directly and one remote controls the volume. If the system is for music only, this changes nothing. |
| Room to grow | evenly matched | The same expansion options on both. |
| Amplifier class | depends | Rega Elex Mk4 is Class A/B and NAD C 3050 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. |
| Price | evenly matched | Priced within a few per cent of each other. |
| Watts per dollar | B | NAD C 3050 is the cheaper watt - about $19 per watt against $26. A blunt measure, and it says nothing about how either sounds, but it is the honest one for raw output. |
A Rega Elex Mk4 B NAD C 3050
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 3050 has the edge on paper, though not by much. The rows marked "depends" are more likely to decide this than the score is. If this sits under a television, NAD C 3050 is the one to buy - HDMI ARC means the TV remote controls the volume and there is no second box in the way.
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.