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 | B | Primare I35 Prisma has more power - 150W against 105W into 8 ohms. That is about 1.5dB, which is a small step in loudness but real headroom on peaks. |
| Room size | depends | We rate Devialet Expert 140 Pro the better fit for desk or near-field listening, a small room and a mid-size room, and Primare I35 Prisma for a large room and a very large room. Match the amplifier to the room you actually have, not the one you want. |
| Noise floor | A | Devialet Expert 140 Pro is the quieter design on paper - 130dB against 100dB. Audible mainly with sensitive speakers in a quiet room. |
| Built-in DAC | B | Both decode on board. Primare I35 Prisma goes higher - 768kHz against 192kHz. Very few recordings exist above 192kHz, so treat this as headroom, not as sound quality. |
| Streaming | B | Only Primare I35 Prisma has AirPlay 2 and Chromecast. |
| Analogue inputs | B | Primare I35 Prisma takes more analogue sources - 5 against 1. |
| Phono stage | depends | Devialet Expert 140 Pro has a built-in phono stage (MM,MC) and Primare I35 Prisma 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. |
| Room to grow | B | Only Primare I35 Prisma offers preamp outputs - which decides whether you can add a subwoofer or a power amplifier later without replacing the box. |
| Amplifier class | depends | Devialet Expert 140 Pro is ADH (Analog Digital Hybrid) and Primare I35 Prisma is Class D. Class D runs cool and draws almost nothing at idle. Modern examples of both measure well - judge by the rest of the page. |
| Shelf space | depends | Devialet Expert 140 Pro takes up about 23% less shelf area (1521cm² against 1970cm²), and it is 59mm shallower, which is the measurement that decides whether a rack door shuts. |
| Price | B | Primare I35 Prisma costs less - $5,795 against $6,500 at list. |
| Watts per dollar | B | Primare I35 Prisma is the cheaper watt - about $39 per watt against $62. A blunt measure, and it says nothing about how either sounds, but it is the honest one for raw output. |
A Devialet Expert 140 Pro B Primare I35 Prisma
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?
Primare I35 Prisma is the easier recommendation: it leads on most of the measured areas and costs less. Take Devialet Expert 140 Pro if one of the "depends" rows above describes your system. If you play records, Devialet Expert 140 Pro 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.