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 | evenly matched | Effectively the same output - 50W against 50W into 8 ohms is under 1dB, which is not an audible difference in loudness. |
| Grip on hard loads | B | Audiolab 6000A MKII holds up better into a 4-ohm load: its output increases strongly to 75W, where the other barely increases. That matters with demanding speakers far more than the 8-ohm figure does. |
| Noise floor | B | Audiolab 6000A MKII is the quieter design on paper - 110dB against 90dB. Audible mainly with sensitive speakers in a quiet room. |
| Built-in DAC | A | Both decode on board. NAD C3030 goes higher - 384kHz against 192kHz. Very few recordings exist above 192kHz, so treat this as headroom, not as sound quality. |
| Room to grow | B | Only Audiolab 6000A MKII offers preamp outputs and a pre-out/main-in loop - which decides whether you can add a subwoofer or a power amplifier later without replacing the box. |
| Amplifier class | depends | NAD C3030 is Class D and Audiolab 6000A MKII 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. |
| Price | B | Audiolab 6000A MKII costs less - $1,099 against $1,199 at list. |
A NAD C3030 B Audiolab 6000A MKII
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?
Audiolab 6000A MKII 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 - Audiolab 6000A MKII 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.