These are not the same size of amplifier: Rotel RB-1582 MkII has roughly 2x the power of Audiolab 9000P. That is about 3dB, 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 | A | Rotel RB-1582 MkII has more power - 200W against 100W into 8 ohms. That is about 3dB, so it plays usefully louder before it runs out and has more in hand on peaks. |
| Analogue inputs | evenly matched | The same number of line-level inputs (2). |
| Price | B | Audiolab 9000P costs less - $1,499 against $2,499 at list. |
A Rotel RB-1582 MkII B Audiolab 9000P
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 RB-1582 MkII is ahead, but on only 1 of the measured areas, and it costs about 67% more. That is a lot of money for a narrow margin - Audiolab 9000P is the sensible buy unless a specific feature above decides it for you. 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 RB-1582 MkII 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 100 watts would be headroom you pay for and never hear. Think about the whole system: the roughly $1,000 saved by taking the cheaper one would buy better speakers or a subwoofer, which does more for the sound than the difference between two competent amplifiers.
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.