These are not the same size of amplifier: Mark Levinson No.536 has roughly 2.7x the power of Devialet Astra. That is about 4.3dB, 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 | Mark Levinson No.536 has more power - 400W against 150W into 8 ohms. That is about 4.3dB, so it plays usefully louder before it runs out and has more in hand on peaks. |
| Room size | depends | We rate Devialet Astra the better fit for desk or near-field listening, a small room and a mid-size room, and Mark Levinson No.536 for a very large room. Match the amplifier to the room you actually have, not the one you want. |
| Grip on hard loads | evenly matched | Both behave much the same into 4 ohms - output nearly doubles (300W and 800W). |
| Built-in DAC | A | Devialet Astra has a DAC on board; the other needs an external one, which is another box, another power lead and another purchase. |
| Analogue inputs | evenly matched | The same number of line-level inputs (2). |
| Phono stage | depends | Devialet Astra has a built-in phono stage (MM/MC with 13 equalization curves and adjustable cartridge loading) and Mark Levinson No.536 does not. Decisive if you own a turntable, completely irrelevant if you do not - and an outboard phono stage is easy to add later either way. |
| Amplifier class | depends | Devialet Astra is ADH (Analog Digital Hybrid) and Mark Levinson No.536 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. |
| Price | B | Mark Levinson No.536 costs less - $18,500 against $20,000 at list. |
| Watts per dollar | B | Mark Levinson No.536 is the cheaper watt - about $46 per watt against $133. A blunt measure, and it says nothing about how either sounds, but it is the honest one for raw output. |
A Devialet Astra B Mark Levinson No.536
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.536 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 - Mark Levinson No.536 has the headroom, and headroom is what stops an amplifier hardening up on peaks. At desk distance or in a small room, 150 watts is already more than most people ever use, and the extra 250 watts would be headroom you pay for and never hear - we rate Mark Levinson No.536 poorly for near-field use for exactly that reason. If you play records, Devialet Astra saves you buying a phono stage; if you do not, ignore that row entirely.
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.