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 | Marantz PM8006 has more power - 70W against 50W 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 Audiolab 6000A MKII the better fit for desk or near-field listening and a small room, and Marantz PM8006 for a mid-size room, 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 | evenly matched | Both behave much the same into 4 ohms - output increases modestly (75W and 100W). |
| Noise floor | A | Audiolab 6000A MKII is the quieter design on paper - 110dB against 106dB. Audible mainly with sensitive speakers in a quiet room. |
| Built-in DAC | A | Audiolab 6000A MKII has a DAC on board; the other needs an external one, which is another box, another power lead and another purchase. |
| Analogue inputs | B | Marantz PM8006 takes more analogue sources - 5 against 3. |
| Room to grow | A | Only Audiolab 6000A MKII offers a pre-out/main-in loop - which decides whether you can add a subwoofer or a power amplifier later without replacing the box. |
| Shelf space | depends | Audiolab 6000A MKII takes up about 25% less shelf area (1328cm² against 1772cm²), and it is 102mm shallower, which is the measurement that decides whether a rack door shuts. |
| Price | A | Audiolab 6000A MKII costs less - $1,099 against $1,499 at list. |
A Audiolab 6000A MKII B Marantz PM8006
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 you already own a DAC or a streamer, the built-in one is money you are paying twice for, and Marantz PM8006 becomes the more rational buy. Think about the whole system: the roughly $400 saved by taking the cheaper one would buy better speakers or a subwoofer, which does more for the sound than the difference between two competent amplifiers.
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.