Different price classes - Marantz PM6007 costs roughly 2.6x what Yamaha A-S301 does. Expect it to lead on paper; the question is whether you will hear the difference through the speakers you own.
| Area | Better | Why |
|---|
| Power | A | Yamaha A-S301 has more power - 60W against 45W into 8 ohms. That is about 1.2dB, which is a small step in loudness but real headroom on peaks. |
| Grip on hard loads | B | Marantz PM6007 holds up better into a 4-ohm load: its output increases modestly to 60W, where the other barely increases. 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 99dB. 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. |
| Analogue inputs | A | Yamaha A-S301 takes more analogue sources - 6 against 4. |
| Room to grow | evenly matched | The same expansion options on both. |
| Price | A | Yamaha A-S301 costs less - $350 against $899 at list. |
| Watts per dollar | A | Yamaha A-S301 is the cheaper watt - about $6 per watt against $20. A blunt measure, and it says nothing about how either sounds, but it is the honest one for raw output. |
A Yamaha A-S301 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?
Yamaha A-S301 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 - Marantz PM6007 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 $549 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.