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 | Buchardt I150 has more power - 150W against 120W into 8 ohms. That is about 1dB, which is a small step in loudness but real headroom on peaks. |
| Room size | depends | We rate Rotel RA-1572 MKII the better fit for desk or near-field listening, a small room and a mid-size room, and Buchardt I150 for a very large room. Match the amplifier to the room you actually have, not the one you want. |
| Grip on hard loads | B | Buchardt I150 holds up better into a 4-ohm load: its output nearly doubles to 300W, where the other increases strongly. That matters with demanding speakers far more than the 8-ohm figure does. |
| Noise floor | B | Buchardt I150 is the quieter design on paper - 121dB against 100dB. Audible mainly with sensitive speakers in a quiet room. |
| Built-in DAC | B | Both decode on board. Buchardt I150 goes higher - 394kHz against 384kHz. Very few recordings exist above 192kHz, so treat this as headroom, not as sound quality. |
| Streaming | evenly matched | Only Rotel RA-1572 MKII has Roon. Neither list is longer in a way that matters - check the one service you actually pay for. |
| Analogue inputs | A | Rotel RA-1572 MKII takes more analogue sources - 4 against 1. |
| Phono stage | depends | Rotel RA-1572 MKII has a built-in phono stage (MM) and Buchardt I150 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 Rotel RA-1572 MKII has a headphone output. Worth something if you listen late, nothing if you never do. |
| Amplifier class | depends | Rotel RA-1572 MKII is Class A/B and Buchardt I150 is Class D. Class A/B runs warm and is the long-established mainstream choice; 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 | Buchardt I150 takes up about 32% less shelf area (1147cm² against 1675cm²), and it is 76mm shallower, which is the measurement that decides whether a rack door shuts. |
| Price | A | Rotel RA-1572 MKII costs less - $2,100 against $2,500 at list. |
A Rotel RA-1572 MKII B Buchardt I150
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?
Buchardt I150 leads across most of the measured areas for a fairly modest premium, so it is the easier pick if the budget stretches. Rotel RA-1572 MKII is the one to take if it does not. If your speakers are a difficult load - 4 ohms nominal, big woofers, or a sensitivity in the low 80s - Buchardt I150 is the safer partner, because how an amplifier behaves when the impedance drops matters more than its 8-ohm rating. If you play records, Rotel RA-1572 MKII 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.