A generation apart: Klipsch The Nines II is the newer design, against a 2020 model. Newer is not automatically better, but the older one is more likely to be discounted or near run-out.
| Area | Better | Why |
|---|
| Bass | A | Klipsch The Nines II digs deeper - 31Hz against 45Hz. |
| Connections | B | Klipsch The Nines II adds phono; KEF LS50 Wireless II adds Wi-Fi and streaming. |
| Size | depends | KEF LS50 Wireless II is easier to place; Klipsch The Nines II is bigger, which usually goes with fuller bass. Your room decides. |
| Expandability | depends | Klipsch The Nines II: a sub output; KEF LS50 Wireless II: a sub output. |
| Price | A | Klipsch The Nines II is cheaper - $2,399 against $2,999, about 20% less. |
A Klipsch The Nines II B KEF LS50 Wireless II
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?
Neither runs away with it - they trade advantages. Let the "depends" rows and your own room settle it. If a subwoofer is in your plans, the bass gap largely stops mattering - you would be crossing over above 45Hz anyway, so judge these on the other rows instead. In a large or open-plan room, Klipsch The Nines II has the cabinet volume to fill it more easily; in a small room, near a wall or at desk distance, KEF LS50 Wireless II 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.