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 - 50W against 45W into 8 ohms is under 1dB, which is not an audible difference in loudness. |
| Grip on hard loads | A | Audiolab 6000A Play holds up better into a 4-ohm load: its output increases strongly to 75W, where the other increases modestly. That matters with demanding speakers far more than the 8-ohm figure does. |
| Noise floor | B | Marantz PM6007 is the quieter design on paper - 102dB against 76dB. Audible mainly with sensitive speakers in a quiet room. |
| Built-in DAC | evenly matched | Both have a DAC on board with much the same capability. |
| Streaming | evenly matched | Only Audiolab 6000A Play has DTS Play-Fi. Neither list is longer in a way that matters - check the one service you actually pay for. |
| Analogue inputs | evenly matched | The same number of line-level inputs (4). |
| Room to grow | A | Only Audiolab 6000A Play offers a pre-out/main-in loop - which decides whether you can add a subwoofer or a power amplifier later without replacing the box. |
| Price | B | Marantz PM6007 costs less - $899 against $1,700 at list. |
| Watts per dollar | B | Marantz PM6007 is the cheaper watt - about $20 per watt against $34. A blunt measure, and it says nothing about how either sounds, but it is the honest one for raw output. |
A Audiolab 6000A Play B Marantz PM6007
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?
Neither runs away with it - they trade advantages. Let the "depends" rows and the speakers you already own settle it. If your speakers are a difficult load - 4 ohms nominal, big woofers, or a sensitivity in the low 80s - Audiolab 6000A Play is the safer partner, because how an amplifier behaves when the impedance drops matters more than its 8-ohm rating. Think about the whole system: the roughly $801 saved by taking the cheaper one would buy better speakers or a subwoofer, and either 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 interface feels 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.