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 | A | Audiolab 6000A MKII is the quieter design on paper - 110dB against 76dB. Audible mainly with sensitive speakers in a quiet room. |
| 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 | B | Only Audiolab Omnia has Roon and DTS Play-Fi. |
| Analogue inputs | B | Audiolab Omnia takes more analogue sources - 4 against 3. |
| 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. |
| Shelf space | depends | Audiolab 6000A MKII takes up about 16% less shelf area (1328cm² against 1582cm²), and it is 59mm shallower, which is the measurement that decides whether a rack door shuts. |
| Price | A | Audiolab 6000A MKII costs less - $1,099 against $2,300 at list. |
| Watts per dollar | A | Audiolab 6000A MKII is the cheaper watt - about $22 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 MKII 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?
Audiolab Omnia is ahead, but on only 1 of the measured areas, and it costs about 109% more. That is a lot of money for a narrow margin - Audiolab 6000A MKII is the sensible buy unless a specific feature above decides it for you. Think about the whole system: the roughly $1,201 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.