These are not the same size of amplifier: Hegel H400 has roughly 2x the power of Mark Levinson No.5802. That is about 3dB, 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 | Hegel H400 has more power - 250W against 125W into 8 ohms. That is about 3dB, so it plays usefully louder before it runs out and has more in hand on peaks. |
| Room size | depends | We rate Mark Levinson No.5802 the better fit for desk or near-field listening, a small room and a mid-size room, and Hegel H400 for a very large room. Match the amplifier to the room you actually have, not the one you want. |
| Noise floor | A | Mark Levinson No.5802 is the quieter design on paper - 103dB 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. |
| Streaming | B | Only Hegel H400 has Chromecast and Roon. |
| Room to grow | evenly matched | The same expansion options on both. |
| Headphones | depends | Only Mark Levinson No.5802 has a headphone output. Worth something if you listen late, nothing if you never do. |
| Shelf space | depends | Hegel H400 takes up about 23% less shelf area (1892cm² against 2454cm²), and it is 119mm shallower, which is the measurement that decides whether a rack door shuts. |
| Price | B | Hegel H400 costs less - $7,700 against $8,500 at list. |
| Watts per dollar | B | Hegel H400 is the cheaper watt - about $31 per watt against $68. A blunt measure, and it says nothing about how either sounds, but it is the honest one for raw output. |
A Mark Levinson No.5802 B Hegel H400
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?
Hegel H400 has the edge on paper, though not by much. The rows marked "depends" are more likely to decide this than the score is. 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 - Hegel H400 has the headroom, and headroom is what stops an amplifier hardening up on peaks. At desk distance or in a small room, 125 watts is already more than most people ever use, and the extra 125 watts would be headroom you pay for and never hear - we rate Hegel H400 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.