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 | evenly matched | Effectively the same output - 50W against 50W into 8 ohms is under 1dB, which is not an audible difference in loudness. |
| Grip on hard loads | evenly matched | Both behave much the same into 4 ohms - output increases strongly (75W and 75W). |
| Noise floor | evenly matched | Much the same signal-to-noise ratio (76dB vs 76dB). |
| Built-in DAC | B | Both decode on board. Audiolab Omnia goes higher - 768kHz against 192kHz. Very few recordings exist above 192kHz, so treat this as headroom, not as sound quality. |
| Streaming | evenly matched | Only Audiolab Omnia has Roon. Neither list is longer in a way that matters - check the one service you actually pay for. |
| Analogue inputs | evenly matched | The same number of line-level inputs (4). |
| Room to grow | evenly matched | The same expansion options on both. |
| Built-in sources | depends | Audiolab Omnia has a CD player built in. That is one less box if you still play discs or listen to radio, and dead weight if you do not. |
| Price | A | Audiolab 6000A Play costs less - $1,700 against $2,300 at list. |
| Watts per dollar | A | Audiolab 6000A Play is the cheaper watt - about $34 per watt against $46. A blunt measure, and it says nothing about how either sounds, but it is the honest one for raw output. |
A Audiolab 6000A Play B Audiolab Omnia
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. Think about the whole system: the roughly $600 saved by taking the cheaper one would buy better speakers or a subwoofer, and either 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 interface feels 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.