A valve amplifier against a solid-state one. They are not really rivals: they differ in character, in what they will drive and in what owning them involves, so start there rather than with the watts.
| Area | Better | Why |
|---|
| Power | A | PS Audio Stellar M1200 has more power - 600W against 250W into 8 ohms. That is about 3.8dB, so it plays usefully louder before it runs out and has more in hand on peaks. |
| Grip on hard loads | A | PS Audio Stellar M1200 holds up better into a 4-ohm load: its output nearly doubles to 1200W, where the other barely increases. That matters with demanding speakers far more than the 8-ohm figure does. |
| Noise floor | A | PS Audio Stellar M1200 is the quieter design on paper - 112dB against 109dB. Audible mainly with sensitive speakers in a quiet room. |
| Built-in DAC | B | HiFi Rose RS520 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 (1). |
| Use with a TV | depends | Only HiFi Rose RS520 has HDMI eARC, so the television can drive it directly and one remote controls the volume. If the system is for music only, this changes nothing. |
| Amplifier type | depends | PS Audio Stellar M1200 is Hybrid and HiFi Rose RS520 is Solid State. Valve designs are usually warmer and softer at the limits and need their tubes replaced eventually; solid state is the lower-maintenance choice. This is a taste and ownership decision, not a quality one. |
| Shelf space | depends | HiFi Rose RS520 takes up about 14% less shelf area (1135cm² against 1316cm²), and it is 23mm shallower, which is the measurement that decides whether a rack door shuts. |
| Price | A | PS Audio Stellar M1200 costs less - $3,499 against $3,695 at list. |
| Watts per dollar | A | PS Audio Stellar M1200 is the cheaper watt - about $6 per watt against $15. A blunt measure, and it says nothing about how either sounds, but it is the honest one for raw output. |
A PS Audio Stellar M1200 B HiFi Rose RS520
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?
PS Audio Stellar M1200 has the edge on paper, though not by much. The rows marked "depends" are more likely to decide this than the score is. If your speakers are a difficult load - 4 ohms nominal, big woofers, or a sensitivity in the low 80s - PS Audio Stellar M1200 is the safer partner, because how an amplifier behaves when the impedance drops matters more than its 8-ohm rating. 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 - PS Audio Stellar M1200 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 350 watts would be headroom you pay for and never hear - we rate PS Audio Stellar M1200 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.