A floor-standing against a bookshelf. They are built for different places in a room, so start with where these have to go rather than which looks better on paper.
| Area | Better | Why |
|---|
| Bass | A | Fluance Ai81 digs deeper - 30Hz against 50Hz. |
| Built-in power | A | Fluance Ai81 has the bigger amplifier (150W vs 100W RMS). |
| Connections | B | Kanto YU6 adds phono. |
| Size | depends | Kanto YU6 is easier to place; Fluance Ai81 is bigger, which usually goes with fuller bass. Your room decides. |
| Type | depends | A Powered Floor-standing against a Powered Bookshelf - a different job rather than a better one. |
| Expandability | depends | Fluance Ai81: a sub output; Kanto YU6: a sub output. |
| Price | evenly matched | Much the same money ($499 vs $540 a pair). |
A Fluance Ai81 B Kanto YU6
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 speakers are judged; anything missing on either side is left out rather than guessed.
Which should you choose?
Fluance Ai81 has the edge on paper, though the margin is not large. The rows marked "depends" may matter more to you than the score does. If a subwoofer is in your plans, the bass gap largely stops mattering - you would be crossing over above 50Hz anyway, so judge these on the other rows instead. In a large or open-plan room, Fluance Ai81 has the cabinet volume to fill it more easily; in a small room, near a wall or at desk distance, Kanto YU6 is the easier speaker to get right.
And remember what a spec sheet cannot show: how each looks in your room and whether the finish suits it, what dealer support and warranty are like where you live, and how they actually sound to you. If you can hear them first - ideally with your own music - that will tell you more than any number above.