These sit in different price classes - KEF LS LUXE costs roughly 1.7x what Cambridge Audio L R X does. Expect it to lead on paper; the question is whether the gap is audible enough in your room to be worth it.
| Area | Better | Why |
|---|
| Bass | B | Cambridge Audio L R X digs deeper - 35Hz against 42Hz. A subwoofer would even that out. |
| Built-in power | B | Cambridge Audio L R X has the bigger amplifier (800W vs 380W RMS). |
| Connections | evenly matched | The same set of inputs and streaming options. |
| Size | depends | Similar cabinet size - neither is easier to fit. |
| Cabinet | depends | Ported vs Passive Radiator. |
| Price | B | Cambridge Audio L R X is cheaper - $2,299 against $4,000, about 43% less; arguably a different class. |
A KEF LS LUXE B Cambridge Audio L R X
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?
Cambridge Audio L R X is the easier recommendation: it leads on most of the measured areas and costs less. Take KEF LS LUXE if its size, looks or fit in your room suit you better. If a subwoofer is in your plans, the bass gap largely stops mattering - you would be crossing over above 42Hz anyway, so judge these on the other rows instead. Think about the whole system, not just the speakers: the roughly $1,701 saved by taking the cheaper pair would buy a subwoofer or a better amplifier, and either usually does more for the sound than the difference between these two.
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.