These are not the same size of amplifier: Hegel H30A has roughly 4.4x the power of Hegel H400. That is about 6.4dB, 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 | Hegel H30A has more power - 1100W against 250W into 8 ohms. That is about 6.4dB - a different class of amplifier rather than a bigger version of the same one, and far more than most rooms will ever ask for. |
| Speaker load rating | B | Hegel H30A is rated down to 1 ohms against 2, so it is the safer partner for a low-impedance speaker. |
| Bass control | A | Hegel H400 has the higher damping factor (4000 vs 500), which usually means a tighter grip on a woofer. Above about 100 the returns flatten out, so read this as a tendency rather than a ranking. |
| Noise floor | evenly matched | Much the same signal-to-noise ratio (100dB vs 100dB). |
| Built-in DAC | A | Hegel H400 has a DAC on board; the other needs an external one, which is another box, another power lead and another purchase. |
| Analogue inputs | A | Hegel H400 takes more analogue sources - 3 against 2. |
| Shelf space | depends | Hegel H400 takes up about 23% less shelf area (1892cm² against 2473cm²), and it is 135mm shallower, which is the measurement that decides whether a rack door shuts. |
| Price | A | Hegel H400 costs less - $7,700 against $20,000 at list. |
| Watts per dollar | B | Hegel H30A is the cheaper watt - about $18 per watt against $31. A blunt measure, and it says nothing about how either sounds, but it is the honest one for raw output. |
A Hegel H400 B Hegel H30A
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?
Neither runs away with it - they trade advantages. Let the "depends" rows and the speakers you already own settle it. 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 H30A has the headroom, and headroom is what stops an amplifier hardening up on peaks. At desk distance or in a small room, 250 watts is already more than most people ever use, and the extra 850 watts would be headroom you pay for and never hear - we rate Hegel H30A poorly for near-field use for exactly that reason. If you already own a DAC or a streamer, the built-in one is money you are paying twice for, and Hegel H30A becomes the more rational buy.
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.