These are not the same size of amplifier: Yamaha A-S801 has roughly 2x the power of Audiolab 6000A. 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 | Yamaha A-S801 has more power - 100W against 50W into 8 ohms. That is about 3dB, so it plays usefully louder before it runs out and has more in hand on peaks. |
| Room size | depends | We rate Yamaha A-S801 the better fit for a mid-size room, a large room and a very large room, and Audiolab 6000A for desk or near-field listening and a small room. Match the amplifier to the room you actually have, not the one you want. |
| Noise floor | A | Yamaha A-S801 is the quieter design on paper - 99dB against 76dB. Audible mainly with sensitive speakers in a quiet room. |
| Built-in DAC | A | Both decode on board. Yamaha A-S801 goes higher - 384kHz against 192kHz. Very few recordings exist above 192kHz, so treat this as headroom, not as sound quality. |
| Analogue inputs | A | Yamaha A-S801 takes more analogue sources - 6 against 4. |
| Room to grow | B | Only Audiolab 6000A offers a pre-out/main-in loop - which decides whether you can add a subwoofer or a power amplifier later without replacing the box. |
| Price | evenly matched | Priced within a few per cent of each other. |
| Watts per dollar | A | Yamaha A-S801 is the cheaper watt - about $9 per watt against $18. A blunt measure, and it says nothing about how either sounds, but it is the honest one for raw output. |
A Yamaha A-S801 B Audiolab 6000A
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?
Yamaha A-S801 has the edge on paper, though not by much. The rows marked "depends" are more likely to decide this than the score is. 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 - Yamaha A-S801 has the headroom, and headroom is what stops an amplifier hardening up on peaks. At desk distance or in a small room, 50 watts is already more than most people ever use, and the extra 50 watts would be headroom you pay for and never hear - we rate Yamaha A-S801 poorly for near-field use for exactly that reason.
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.