These are not the same size of amplifier: Rotel RA-1572 MKII has roughly 2.4x the power of MOON 250i v2. That is about 3.8dB, 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 | Rotel RA-1572 MKII has more power - 120W against 50W into 8 ohms. That is about 3.8dB, so it plays usefully louder before it runs out and has more in hand on peaks. |
| Room size | depends | We rate MOON 250i v2 the better fit for desk or near-field listening and a small room, and Rotel RA-1572 MKII for a mid-size room, a large room and a very large room. Match the amplifier to the room you actually have, not the one you want. |
| Grip on hard loads | A | MOON 250i v2 holds up better into a 4-ohm load: its output nearly doubles to 100W, where the other increases strongly. That matters with demanding speakers far more than the 8-ohm figure does. |
| Noise floor | evenly matched | Much the same signal-to-noise ratio (101dB vs 100dB). |
| Built-in DAC | B | Rotel RA-1572 MKII has a DAC on board; the other needs an external one, which is another box, another power lead and another purchase. |
| Analogue inputs | A | MOON 250i v2 takes more analogue sources - 6 against 4. |
| Price | B | Rotel RA-1572 MKII costs less - $2,100 against $2,400 at list. |
| Watts per dollar | B | Rotel RA-1572 MKII is the cheaper watt - about $18 per watt against $48. A blunt measure, and it says nothing about how either sounds, but it is the honest one for raw output. |
A MOON 250i v2 B Rotel RA-1572 MKII
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?
Rotel RA-1572 MKII 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 - MOON 250i v2 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 - Rotel RA-1572 MKII has the headroom, and headroom is what stops an amplifier hardening up on peaks. At desk distance or in a small room, 50 watts is already more than most people ever use, and the extra 70 watts would be headroom you pay for and never hear - we rate Rotel RA-1572 MKII 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.