A floor-standing against a bookshelf. They are built for different places in a room, so start with where these have to go rather than which looks better on paper.
| Area | Better | Why |
|---|
| Bass | evenly matched | Much the same reach (30Hz vs 28Hz). |
| Built-in power | evenly matched | Similar onboard amplification (670W vs 600W RMS). |
| Connections | evenly matched | The same set of inputs and streaming options. |
| Size | depends | Dynaudio Focus 30 is easier to place; JBL 4329P is bigger, which usually goes with fuller bass. Your room decides. |
| Type | depends | A Powered Floor-standing against a Powered Bookshelf - a different job rather than a better one. |
| 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 30: a sub output; JBL 4329P: a sub output. JBL 4329P sits in a wider range (8 models), so a matched surround system is easier later. |
| Price | B | JBL 4329P is cheaper - $4,500 against $8,250, about 45% less; arguably a different class. |
A Dynaudio Focus 30 B JBL 4329P
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. Think about the whole system, not just the speakers: the roughly $3,750 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.