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 | A | Advance Paris Playstream A7 has more power - 115W against 70W into 8 ohms. That is about 2.2dB, so it plays usefully louder before it runs out and has more in hand on peaks. |
| Room size | depends | We rate Advance Paris Playstream A7 the better fit for a large room and a very large room, and Marantz Model 40n for a small 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 (180W and 100W). |
| Noise floor | B | Marantz Model 40n is the quieter design on paper - 106dB against 98dB. 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 | Advance Paris Playstream A7 takes more analogue sources - 4 against 3. |
| Shelf space | depends | Advance Paris Playstream A7 takes up about 25% less shelf area (1591cm² against 2126cm²), and it is 111mm shallower, which is the measurement that decides whether a rack door shuts. |
| Price | evenly matched | Priced within a few per cent of each other. |
| Watts per dollar | A | Advance Paris Playstream A7 is the cheaper watt - about $22 per watt against $36. A blunt measure, and it says nothing about how either sounds, but it is the honest one for raw output. |
A Advance Paris Playstream A7 B Marantz Model 40n
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?
Advance Paris Playstream A7 has the edge on paper, though not by much. The rows marked "depends" are more likely to decide this than the score is. Start with the room. In a large or open-plan room, or with speakers that are hard to drive - low sensitivity, or an impedance that dips - Advance Paris Playstream A7 has the headroom, and headroom is what stops an amplifier hardening up on peaks. At desk distance or in a small room, 70 watts is already more than most people ever use, and the extra 45 watts would be headroom you pay for and never hear - we rate Advance Paris Playstream A7 poorly for near-field use for exactly that reason.
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.