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 increases modestly (115W and 100W). |
| Noise floor | A | LEAK Stereo 230 is the quieter design on paper - 109dB against 106dB. Audible mainly with sensitive speakers in a quiet room. |
| Built-in DAC | A | Both decode on board. LEAK Stereo 230 goes higher - 768kHz against 192kHz. Very few recordings exist above 192kHz, so treat this as headroom, not as sound quality. |
| Streaming | B | Only Marantz Model 40n has AirPlay 2, Roon and HEOS. |
| Analogue inputs | B | Marantz Model 40n takes more analogue sources - 3 against 2. |
| Room to grow | evenly matched | The same expansion options on both. |
| Shelf space | depends | LEAK Stereo 230 takes up about 32% less shelf area (1454cm² against 2126cm²), and it is 39mm shallower, which is the measurement that decides whether a rack door shuts. |
| Price | A | LEAK Stereo 230 costs less - $1,695 against $2,499 at list. |
| Watts per dollar | A | LEAK Stereo 230 is the cheaper watt - about $23 per watt against $36. A blunt measure, and it says nothing about how either sounds, but it is the honest one for raw output. |
A LEAK Stereo 230 B Marantz Model 40n
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?
LEAK Stereo 230 has the edge on paper, though not by much. The rows marked "depends" are more likely to decide this than the score is. Think about the whole system: the roughly $804 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.