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 Audio AXR100 has more power - 100W against 75W into 8 ohms. That is about 1.2dB, which is a small step in loudness but real headroom on peaks. |
| Built-in DAC | A | Both decode on board, but only Marantz Stereo 70s handles DSD. |
| Streaming | A | Only Marantz Stereo 70s has AirPlay 2 and HEOS. |
| Use with a TV | depends | Only Marantz Stereo 70s has HDMI ARC, so the television can drive it directly and one remote controls the volume. If the system is for music only, this changes nothing. |
| Room to grow | A | Only Marantz Stereo 70s offers preamp outputs - which decides whether you can add a subwoofer or a power amplifier later without replacing the box. |
| Price | B | Cambridge Audio AXR100 costs less - $699 against $1,000 at list. |
| Watts per dollar | B | Cambridge Audio AXR100 is the cheaper watt - about $7 per watt against $13. A blunt measure, and it says nothing about how either sounds, but it is the honest one for raw output. |
A Marantz Stereo 70s B Cambridge Audio AXR100
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?
Marantz Stereo 70s is ahead, but on only 1 of the measured areas, and it costs about 43% more. That is a lot of money for a narrow margin - Cambridge Audio AXR100 is the sensible buy unless a specific feature above decides it for you. If this sits under a television, Marantz Stereo 70s is the one to buy - HDMI ARC means the TV remote controls the volume and there is no second box in the way. Think about the whole system: the roughly $301 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.