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 - 125W against 105W into 8 ohms is under 1dB, which is not an audible difference in loudness. |
| Room size | depends | We rate Mark Levinson No.5805 the better fit for a large room and a very large room, and Devialet Expert 140 Pro for a small room. Match the amplifier to the room you actually have, not the one you want. |
| Noise floor | B | Devialet Expert 140 Pro is the quieter design on paper - 130dB against 103dB. Audible mainly with sensitive speakers in a quiet room. |
| Built-in DAC | A | Both decode on board. Mark Levinson No.5805 goes higher - 384kHz against 192kHz. Very few recordings exist above 192kHz, so treat this as headroom, not as sound quality. |
| Streaming | evenly matched | Only Devialet Expert 140 Pro has Roon. Neither list is longer in a way that matters - check the one service you actually pay for. |
| Analogue inputs | A | Mark Levinson No.5805 takes more analogue sources - 3 against 1. |
| Room to grow | A | Only Mark Levinson No.5805 offers preamp outputs - which decides whether you can add a subwoofer or a power amplifier later without replacing the box. |
| Headphones | depends | Only Mark Levinson No.5805 has a headphone output. Worth something if you listen late, nothing if you never do. |
| Amplifier class | depends | Mark Levinson No.5805 is Class A/B and Devialet Expert 140 Pro is ADH (Analog Digital Hybrid). 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 140 Pro takes up about 38% less shelf area (1521cm² against 2454cm²), and it is 162mm shallower, which is the measurement that decides whether a rack door shuts. |
| Price | B | Devialet Expert 140 Pro costs less - $6,500 against $10,500 at list. |
| Watts per dollar | B | Devialet Expert 140 Pro is the cheaper watt - about $62 per watt against $84. A blunt measure, and it says nothing about how either sounds, but it is the honest one for raw output. |
A Mark Levinson No.5805 B Devialet Expert 140 Pro
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?
Mark Levinson No.5805 is ahead, but on only 1 of the measured areas, and it costs about 62% more. That is a lot of money for a narrow margin - Devialet Expert 140 Pro is the sensible buy unless a specific feature above decides it for you. Think about the whole system: the roughly $4,000 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.