A valve amplifier against a solid-state one. They are not really rivals: they differ in character, in what they will drive and in what owning them involves, so start there rather than with the watts.
| Area | Better | Why |
|---|
| Power | B | Marantz PM7000N has more power - 60W against 35W into 8 ohms. That is about 2.3dB, so it plays usefully louder before it runs out and has more in hand on peaks. |
| Room size | depends | We rate Cayin Jazz 70 the better fit for desk or near-field listening, and Marantz PM7000N for a very large room. Match the amplifier to the room you actually have, not the one you want. |
| Grip on hard loads | B | Marantz PM7000N holds up better into a 4-ohm load: its output increases modestly to 80W, where the other barely increases. That matters with demanding speakers far more than the 8-ohm figure does. |
| Noise floor | B | Marantz PM7000N is the quieter design on paper - 115dB against 100dB. 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 | evenly matched | The same number of line-level inputs (3). |
| Phono stage | depends | Marantz PM7000N has a built-in phono stage (MM) and Cayin Jazz 70 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. |
| Amplifier type | depends | Cayin Jazz 70 is Tube and Marantz PM7000N is Solid State. Valve designs are usually warmer and softer at the limits and need their tubes replaced eventually; solid state is the lower-maintenance choice. This is a taste and ownership decision, not a quality one. |
| Shelf space | depends | Cayin Jazz 70 takes up about 40% less shelf area (1014cm² against 1684cm²), and it is 43mm shallower, which is the measurement that decides whether a rack door shuts. |
| Price | B | Marantz PM7000N costs less - $1,299 against $1,399 at list. |
| Watts per dollar | B | Marantz PM7000N is the cheaper watt - about $22 per watt against $40. A blunt measure, and it says nothing about how either sounds, but it is the honest one for raw output. |
A Cayin Jazz 70 B Marantz PM7000N
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 PM7000N 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 PM7000N is the safer partner, because how an amplifier behaves when the impedance drops matters more than its 8-ohm rating. 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 - Marantz PM7000N has the headroom, and headroom is what stops an amplifier hardening up on peaks. At desk distance or in a small room, 35 watts is already more than most people ever use, and the extra 25 watts would be headroom you pay for and never hear.
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.