These are not the same size of amplifier: Michi X5 Series 2 has roughly 2.4x the power of Devialet Expert 220 Pro. That is about 3.7dB, 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 | Michi X5 Series 2 has more power - 390W against 165W into 8 ohms. That is about 3.7dB, so it plays usefully louder before it runs out and has more in hand on peaks. |
| Speaker load rating | A | Devialet Expert 220 Pro is rated down to 2 ohms against 4, so it is the safer partner for a low-impedance speaker. |
| Noise floor | A | Devialet Expert 220 Pro is the quieter design on paper - 130dB against 102dB. Audible mainly with sensitive speakers in a quiet room. |
| Built-in DAC | B | Both decode on board. Michi X5 Series 2 goes higher - 384kHz against 192kHz. Very few recordings exist above 192kHz, so treat this as headroom, not as sound quality. |
| Streaming | evenly matched | The same streaming platforms and services on both. |
| Analogue inputs | B | Michi X5 Series 2 takes more analogue sources - 5 against 2. |
| Room to grow | evenly matched | The same expansion options on both. |
| Amplifier class | depends | Devialet Expert 220 Pro is ADH (Analog Digital Hybrid) and Michi X5 Series 2 is Class A/B. Class A/B runs warm and is the long-established mainstream choice. Modern examples of both measure well - judge by the rest of the page. |
| Shelf space | depends | Devialet Expert 220 Pro takes up about 31% less shelf area (1521cm² against 2192cm²), and it is 55mm shallower, which is the measurement that decides whether a rack door shuts. |
| Price | B | Michi X5 Series 2 costs less - $9,499 against $10,000 at list. |
| Watts per dollar | B | Michi X5 Series 2 is the cheaper watt - about $24 per watt against $61. A blunt measure, and it says nothing about how either sounds, but it is the honest one for raw output. |
A Devialet Expert 220 Pro B Michi X5 Series 2
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?
Michi X5 Series 2 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 - Michi X5 Series 2 has the headroom, and headroom is what stops an amplifier hardening up on peaks. At desk distance or in a small room, 165 watts is already more than most people ever use, and the extra 225 watts would be headroom you pay for and never hear - we rate Michi X5 Series 2 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.