A generation apart: Onkyo Creator Series GX-30ARC is the newer design, against a 2018 model. Newer is not automatically better, but the older one is more likely to be discounted or near run-out.
| Area | Better | Why |
|---|
| Bass | A | Onkyo Creator Series GX-30ARC digs deeper - 55Hz against 62Hz. A subwoofer would even that out. |
| Built-in power | evenly matched | Similar onboard amplification (100W vs 100W RMS). |
| Connections | A | Onkyo Creator Series GX-30ARC adds HDMI. |
| Size | depends | Onkyo Creator Series GX-30ARC is easier to place; Klipsch R-15PM is bigger, which usually goes with fuller bass. Your room decides. |
| Expandability | depends | Onkyo Creator Series GX-30ARC: a sub output; Klipsch R-15PM: a sub output. Klipsch R-15PM sits in a wider range (5 models), so a matched surround system is easier later. |
| Price | A | Onkyo Creator Series GX-30ARC is cheaper - $349 against $499, about 30% less. |
A Onkyo Creator Series GX-30ARC B Klipsch R-15PM
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?
Onkyo Creator Series GX-30ARC is the easier recommendation: it leads on most of the measured areas and costs less. Take Klipsch R-15PM if its size, looks or fit in your room suit you better. If a subwoofer is in your plans, the bass gap largely stops mattering - you would be crossing over above 62Hz anyway, so judge these on the other rows instead. In a large or open-plan room, Klipsch R-15PM has the cabinet volume to fill it more easily; in a small room, near a wall or at desk distance, Onkyo Creator Series GX-30ARC is the easier speaker to get right.
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.