Different kinds of product: one is active with its amplifier built in, the other passive and needs one. Judge them on how you want to own the system, not just the specs.
| Area | Better | Why |
|---|
| Bass | A | Dynaudio Focus 50 digs deeper - 22Hz against 46Hz. |
| What you buy | depends | Dynaudio Focus 50 is a complete system - just add a source. B&W 702 S3 also needs an amplifier: more money and another box, but you choose it. |
| Connections | depends | Dynaudio Focus 50 has Bluetooth, Wi-Fi and streaming built in. With B&W 702 S3 that all comes from the amplifier you pair it with. |
| Upgrade path | depends | B&W 702 S3 can be re-amped later and outlive several amplifiers; Dynaudio Focus 50 ages as one unit. |
| Size | depends | Similar cabinet size - neither is easier to fit. |
| Cabinet | depends | Sealed vs Ported. Sealed is tighter and happier near a wall; ported digs lower but wants space behind it. |
| Expandability | depends | Dynaudio Focus 50: a sub output; B&W 702 S3: bi-amping. B&W 702 S3 sits in a wider range (8 models), so a matched surround system is easier later. |
| Price | B | B&W 702 S3 is cheaper - $6,998 against $11,000, about 36% less. Speakers only - an amplifier narrows that gap. |
A Dynaudio Focus 50 B B&W 702 S3
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?
Dynaudio Focus 50 suits you if you want one box, ready to play, with nothing else to buy. B&W 702 S3 suits you if you already have an amplifier, want to choose the electronics, or expect to upgrade in stages. Neither is the better speaker in the abstract. If a subwoofer is in your plans, the bass gap largely stops mattering - you would be crossing over above 46Hz anyway, which makes the cheaper B&W 702 S3 much easier to justify. Think about the whole system, not just the speakers: the roughly $4,002 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.