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 | HiFi Rose RS520 has more power - 250W against 130W into 8 ohms. That is about 2.8dB, so it plays usefully louder before it runs out and has more in hand on peaks. |
| Room size | depends | We rate JBL SA750 75th Anniversary Edition the better fit for desk or near-field listening, a small room and a mid-size room, and HiFi Rose RS520 for a very large room. Match the amplifier to the room you actually have, not the one you want. |
| Grip on hard loads | A | JBL SA750 75th Anniversary Edition holds up better into a 4-ohm load: its output increases strongly to 200W, where the other barely increases. That matters with demanding speakers far more than the 8-ohm figure does. |
| Noise floor | A | JBL SA750 75th Anniversary Edition is the quieter design on paper - 112dB against 109dB. Audible mainly with sensitive speakers in a quiet room. |
| Built-in DAC | B | Both decode on board. HiFi Rose RS520 goes higher - 768kHz against 192kHz. Very few recordings exist above 192kHz, so treat this as headroom, not as sound quality. |
| Streaming | A | Only JBL SA750 75th Anniversary Edition has AirPlay 2 and Chromecast. |
| Analogue inputs | A | JBL SA750 75th Anniversary Edition takes more analogue sources - 4 against 1. |
| Phono stage | depends | JBL SA750 75th Anniversary Edition has a built-in phono stage (MM,MC) and HiFi Rose RS520 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 | evenly matched | The same expansion options on both. |
| Headphones | depends | Only JBL SA750 75th Anniversary Edition has a headphone output. Worth something if you listen late, nothing if you never do. |
| Amplifier class | depends | JBL SA750 75th Anniversary Edition is Class G and HiFi Rose RS520 is Class AD. Class G/H switches its supply rails to cut the heat a Class A/B design wastes. Modern examples of both measure well - judge by the rest of the page. |
| Shelf space | depends | HiFi Rose RS520 takes up about 34% less shelf area (1135cm² against 1718cm²), and it is 53mm shallower, which is the measurement that decides whether a rack door shuts. |
| Price | A | JBL SA750 75th Anniversary Edition costs less - $3,000 against $3,695 at list. |
| Watts per dollar | B | HiFi Rose RS520 is the cheaper watt - about $15 per watt against $23. A blunt measure, and it says nothing about how either sounds, but it is the honest one for raw output. |
A JBL SA750 75th Anniversary Edition 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?
JBL SA750 75th Anniversary Edition 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 - JBL SA750 75th Anniversary Edition 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 - 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, 130 watts is already more than most people ever use, and the extra 120 watts would be headroom you pay for and never hear - we rate HiFi Rose RS520 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.