No single best amplifier here. What decides it is what you have to drive, what you need to plug in, and how much of the system you want in one box.
| Area | Better | Why |
|---|
| Power | B | JBL SA750 75th Anniversary Edition has more power - 130W against 100W into 8 ohms. That is about 1.1dB, which is a small step in loudness but real headroom on peaks. |
| Grip on hard loads | B | JBL SA750 75th Anniversary Edition holds up better into a 4-ohm load: its output increases strongly to 200W, where the other barely increases. That matters with demanding speakers far more than the 8-ohm figure does. |
| Noise floor | B | JBL SA750 75th Anniversary Edition is the quieter design on paper - 112dB against 90dB. 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. |
| Streaming | evenly matched | Only NAD Masters Series M10 V2 has BluOS; only JBL SA750 75th Anniversary Edition has Chromecast. Neither list is longer in a way that matters - check the one service you actually pay for. |
| Analogue inputs | B | JBL SA750 75th Anniversary Edition takes more analogue sources - 4 against 2. |
| Phono stage | depends | JBL SA750 75th Anniversary Edition has a built-in phono stage (MM,MC) and NAD Masters Series M10 V2 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 JBL SA750 75th Anniversary Edition has a headphone output. Worth something if you listen late, nothing if you never do. |
| Amplifier class | depends | NAD Masters Series M10 V2 is Class D and JBL SA750 75th Anniversary Edition is Class G. Class D runs cool and draws almost nothing at idle; Class G/H switches its supply rails to cut the heat a Class A/B design wastes. Modern examples of both measure well - judge by the rest of the page. |
| Shelf space | depends | NAD Masters Series M10 V2 takes up about 65% less shelf area (606cm² against 1718cm²), and it is 103mm shallower, which is the measurement that decides whether a rack door shuts. |
| Price | evenly matched | Priced within a few per cent of each other. |
| Watts per dollar | B | JBL SA750 75th Anniversary Edition is the cheaper watt - about $23 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 Masters Series M10 V2 B JBL SA750 75th Anniversary Edition
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?
JBL SA750 75th Anniversary Edition 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 - JBL SA750 75th Anniversary Edition is the safer partner, because how an amplifier behaves when the impedance drops matters more than its 8-ohm rating. If you play records, JBL SA750 75th Anniversary Edition 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.