Siblings in KEF's LS series, so they share a family sound. It comes down to size, output and price.
| Area | Better | Why |
|---|
| Bass | A | KEF LSX digs deeper - 59Hz against 79Hz. |
| Built-in power | evenly matched | Similar onboard amplification (200W vs 230W RMS). |
| Connections | evenly matched | The same set of inputs and streaming options. |
| Size | depends | KEF LSX is easier to place; KEF LS50 Wireless is bigger, which usually goes with fuller bass. Your room decides. |
| Expandability | depends | KEF LSX: a sub output; KEF LS50 Wireless: a sub output. |
| Price | A | KEF LSX is cheaper - $1,250 against $2,200, about 43% less; arguably a different class. |
A KEF LSX B KEF LS50 Wireless
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?
KEF LSX 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 79Hz anyway, so judge these on the other rows instead. In a large or open-plan room, KEF LS50 Wireless has the cabinet volume to fill it more easily; in a small room, near a wall or at desk distance, KEF LSX 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.