These are not the same size of amplifier: NAD Masters Series M33 has roughly 2.5x the power of NAD C 700. That is about 4dB, so it is a question of room size and how hard your speakers are to drive, not of one being the better amplifier.
| Area | Better | Why |
|---|
| Power | B | NAD Masters Series M33 has more power - 200W against 80W into 8 ohms. That is about 4dB, so it plays usefully louder before it runs out and has more in hand on peaks. |
| Room size | depends | We rate NAD C 700 the better fit for desk or near-field listening, a small room and a mid-size room, and NAD Masters Series M33 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 | B | NAD Masters Series M33 holds up better into a 4-ohm load: its output nearly doubles to 380W, where the other barely increases. That matters with demanding speakers far more than the 8-ohm figure does. |
| Noise floor | B | NAD Masters Series M33 is the quieter design on paper - 120dB against 84dB. Audible mainly with sensitive speakers in a quiet room. |
| Built-in DAC | A | Both decode on board, but only NAD C 700 handles MQA. |
| Streaming | evenly matched | The same streaming platforms and services on both. |
| Analogue inputs | evenly matched | The same number of line-level inputs (2). |
| Phono stage | depends | NAD Masters Series M33 has a built-in phono stage (MM,MC) and NAD C 700 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. |
| Headphones | depends | Only NAD Masters Series M33 has a headphone output. Worth something if you listen late, nothing if you never do. |
| Shelf space | depends | NAD C 700 takes up about 67% less shelf area (651cm² against 1949cm²), and it is 152mm shallower, which is the measurement that decides whether a rack door shuts. |
| Price | A | NAD C 700 costs less - $1,599 against $5,999 at list. |
| Watts per dollar | A | NAD C 700 is the cheaper watt - about $20 per watt against $30. A blunt measure, and it says nothing about how either sounds, but it is the honest one for raw output. |
A NAD C 700 B NAD Masters Series M33
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?
NAD Masters Series M33 is ahead, but on only 1 of the measured areas, and it costs about 3.8x the price. That is a lot of money for a narrow margin - NAD C 700 is the sensible buy unless a specific feature above decides it for you. If your speakers are a difficult load - 4 ohms nominal, big woofers, or a sensitivity in the low 80s - NAD Masters Series M33 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 - NAD Masters Series M33 has the headroom, and headroom is what stops an amplifier hardening up on peaks. At desk distance or in a small room, 80 watts is already more than most people ever use, and the extra 120 watts would be headroom you pay for and never hear - we rate NAD Masters Series M33 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.