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 | evenly matched | Much the same reach (38Hz vs 39Hz). |
| What you buy | depends | Q Acoustics M40 is a complete system - just add a source. DALI Oberon 5 also needs an amplifier: more money and another box, but you choose it. |
| Connections | depends | Q Acoustics M40 has Bluetooth and streaming built in. With DALI Oberon 5 that all comes from the amplifier you pair it with. |
| Upgrade path | depends | DALI Oberon 5 can be re-amped later and outlive several amplifiers; Q Acoustics M40 ages as one unit. |
| Size | depends | Similar cabinet size - neither is easier to fit. |
| Expandability | A | Q Acoustics M40: a sub output. |
| Price | A | Q Acoustics M40 is cheaper - $999 against $1,299, about 23% less. And that is the whole system. |
A Q Acoustics M40 B DALI Oberon 5
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?
Q Acoustics M40 suits you if you want one box, ready to play, with nothing else to buy. DALI Oberon 5 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.
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.