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 (31Hz vs 32Hz). |
| What you buy | depends | Klipsch The Nines II is a complete system - just add a source. Klipsch RF-7 III also needs an amplifier: more money and another box, but you choose it. |
| Connections | depends | Klipsch The Nines II has Bluetooth, HDMI and phono built in. With Klipsch RF-7 III that all comes from the amplifier you pair it with. |
| Upgrade path | depends | Klipsch RF-7 III can be re-amped later and outlive several amplifiers; Klipsch The Nines II ages as one unit. |
| Size | depends | Klipsch The Nines II is easier to place; Klipsch RF-7 III is bigger, which usually goes with fuller bass. Your room decides. |
| Type | depends | A Powered Bookshelf against a Passive Floor-standing - a different job rather than a better one. |
| Expandability | depends | Klipsch The Nines II: a sub output; Klipsch RF-7 III: bi-amping. |
| Price | A | Klipsch The Nines II is cheaper - $2,399 against $4,398, about 45% less; arguably a different class. And that is the whole system. |
A Klipsch The Nines II B Klipsch RF-7 III
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?
Klipsch The Nines II suits you if you want one box, ready to play, with nothing else to buy. Klipsch RF-7 III 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. In a large or open-plan room, Klipsch RF-7 III has the cabinet volume to fill it more easily; in a small room, near a wall or at desk distance, Klipsch The Nines II is the easier speaker to get right. Think about the whole system, not just the speakers: the roughly $1,999 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.