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 | B | HiFi Rose RS520 has more power - 250W against 100W into 8 ohms. That is about 4dB, so it plays usefully louder before it runs out and has more in hand on peaks. |
| Room size | depends | We rate Rogue Audio Stereo 100 the better fit for desk or near-field listening, a small room and a mid-size room, and HiFi Rose RS520 for a large room and a very large room. Match the amplifier to the room you actually have, not the one you want. |
| 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 | A | Rogue Audio Stereo 100 takes more analogue sources - 2 against 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 | Rogue Audio Stereo 100 is Tube 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. |
| Price | B | HiFi Rose RS520 costs less - $3,695 against $4,195 at list. |
| Watts per dollar | B | HiFi Rose RS520 is the cheaper watt - about $15 per watt against $42. A blunt measure, and it says nothing about how either sounds, but it is the honest one for raw output. |
A Rogue Audio Stereo 100 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?
HiFi Rose RS520 is the easier recommendation: it leads on most of the measured areas and costs less. Take Rogue Audio Stereo 100 if one of the "depends" rows above describes your system. 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 - HiFi Rose RS520 has the headroom, and headroom is what stops an amplifier hardening up on peaks. At desk distance or in a small room, 100 watts is already more than most people ever use, and the extra 150 watts would be headroom you pay for and never hear - we rate HiFi Rose RS520 poorly for near-field use for exactly that reason. If this sits under a television, HiFi Rose RS520 is the one to buy - HDMI ARC means the TV remote controls the volume and there is no second box in the way.
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.