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 | B | Cambridge EXA100 has more power - 100W against 70W 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 Marantz Model 40n the better fit for a small room, and Cambridge EXA100 for 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 (100W and 155W). |
| Noise floor | A | Marantz Model 40n is the quieter design on paper - 106dB against 91dB. Audible mainly with sensitive speakers in a quiet room. |
| Built-in DAC | B | Both decode on board. Cambridge EXA100 goes higher - 384kHz against 192kHz. Very few recordings exist above 192kHz, so treat this as headroom, not as sound quality. |
| Streaming | A | Only Marantz Model 40n has AirPlay 2 and HEOS. |
| Analogue inputs | B | Cambridge EXA100 takes more analogue sources - 5 against 3. |
| Phono stage | depends | Marantz Model 40n has a built-in phono stage (MM) and Cambridge EXA100 does not. Decisive if you own a turntable, completely irrelevant if you do not - and an outboard phono stage is easy to add later either way. |
| Room to grow | evenly matched | The same expansion options on both. |
| Shelf space | depends | Cambridge EXA100 takes up about 25% less shelf area (1595cm² against 2126cm²), and it is 111mm shallower, which is the measurement that decides whether a rack door shuts. |
| Price | B | Cambridge EXA100 costs less - $2,199 against $2,499 at list. |
| Watts per dollar | B | Cambridge EXA100 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 Marantz Model 40n B Cambridge EXA100
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?
Cambridge EXA100 is the easier recommendation: it leads on most of the measured areas and costs less. Take Marantz Model 40n if one of the "depends" rows above describes your system. If you play records, Marantz Model 40n saves you buying a phono stage; if you do not, ignore that row entirely.
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.