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 - 75W against 70W into 8 ohms is under 1dB, which is not an audible difference in loudness. |
| Grip on hard loads | evenly matched | Both behave much the same into 4 ohms - output nearly doubles (150W and 140W). |
| Built-in DAC | evenly matched | Both have a DAC on board with much the same capability. |
| Streaming | A | Only Cambridge Audio Evo 75 has AirPlay 2, Chromecast and Roon. |
| Analogue inputs | B | Denon PMA-1700NE takes more analogue sources - 3 against 1. |
| Phono stage | depends | Denon PMA-1700NE has a built-in phono stage (MM,MC) and Cambridge Audio Evo 75 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 | A | Only Cambridge Audio Evo 75 offers preamp outputs - which decides whether you can add a subwoofer or a power amplifier later without replacing the box. |
| Amplifier class | depends | Cambridge Audio Evo 75 is Class D and Denon PMA-1700NE is Class A/B. Class D runs cool and draws almost nothing at idle; Class A/B runs warm and is the long-established mainstream choice. Modern examples of both measure well - judge by the rest of the page. |
| Shelf space | depends | Cambridge Audio Evo 75 takes up about 39% less shelf area (1190cm² against 1949cm²), and it is 76mm shallower, which is the measurement that decides whether a rack door shuts. |
| Price | B | Denon PMA-1700NE costs less - $2,099 against $2,499 at list. |
A Cambridge Audio Evo 75 B Denon PMA-1700NE
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?
The usual trade-off: Cambridge Audio Evo 75 measures better, Denon PMA-1700NE costs about 16% less. With most speakers in most rooms that gap is smaller in practice than it looks here. If you play records, Denon PMA-1700NE 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 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.