These sit in different price classes - KEF Coda W costs roughly 1.7x what Wharfedale Diamond Active A1 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 | KEF Coda W digs deeper - 41Hz against 55Hz. |
| Built-in power | evenly matched | Similar onboard amplification (100W vs 100W RMS). |
| Connections | B | KEF Coda W adds HDMI and digital inputs. |
| Size | depends | Similar cabinet size - neither is easier to fit. |
| Expandability | B | KEF Coda W: a sub output. |
| Price | A | Wharfedale Diamond Active A1 is cheaper - $600 against $999, about 40% less; arguably a different class. |
A Wharfedale Diamond Active A1 B KEF Coda W
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?
The usual trade-off: KEF Coda W measures better, Wharfedale Diamond Active A1 costs about about 67% more% less. Whether that gap is worth the money is the call only you can make - and in a normal room it is often smaller than the numbers suggest. If a subwoofer is in your plans, the bass gap largely stops mattering - you would be crossing over above 55Hz anyway, which makes the cheaper Wharfedale Diamond Active A1 much easier to justify. Think about the whole system, not just the speakers: the roughly $399 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.