No single best amplifier here. What decides it is what you have to drive, what you need to plug in, and how much of the system you want in one box.
| Area | Better | Why |
|---|
| Power | A | Audiolab 9000A has more power - 100W against 70W into 8 ohms. That is about 1.5dB, which is a small step in loudness but real headroom on peaks. |
| Room size | depends | We rate Audiolab 9000A the better fit for a large room and a very large room, and Denon PMA-1600NE for a small room. Match the amplifier to the room you actually have, not the one you want. |
| Grip on hard loads | B | Denon PMA-1600NE holds up better into a 4-ohm load: its output nearly doubles to 140W, 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 (110dB vs 108dB). |
| Built-in DAC | B | Both decode on board. Denon PMA-1600NE goes higher - 384kHz against 192kHz. Very few recordings exist above 192kHz, so treat this as headroom, not as sound quality. |
| Analogue inputs | evenly matched | The same number of line-level inputs (3). |
| Room to grow | A | Only Audiolab 9000A offers preamp outputs and a pre-out/main-in loop - which decides whether you can add a subwoofer or a power amplifier later without replacing the box. |
| Shelf space | depends | Audiolab 9000A takes up about 22% less shelf area (1518cm² against 1949cm²), and it is 106mm shallower, which is the measurement that decides whether a rack door shuts. |
| Price | B | Denon PMA-1600NE costs less - $2,099 against $2,999 at list. |
A Audiolab 9000A B Denon PMA-1600NE
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?
Neither runs away with it - they trade advantages. Let the "depends" rows and the speakers you already own settle it. If your speakers are a difficult load - 4 ohms nominal, big woofers, or a sensitivity in the low 80s - Denon PMA-1600NE is the safer partner, because how an amplifier behaves when the impedance drops matters more than its 8-ohm rating. Think about the whole system: the roughly $900 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.