Siblings in Paradigm's Premier series, so they share a family sound. It comes down to size, output and price.
| Area | Better | Why |
|---|
| Bass | B | Paradigm Premier 820 v2 digs deeper - 52Hz against 73Hz. |
| Amplifier needs | evenly matched | Similar sensitivity (92dB vs 93dB) - both want much the same power. |
| Size | depends | Paradigm 500C is easier to place; Paradigm Premier 820 v2 is bigger, which usually goes with fuller bass. Your room decides. |
| Type | depends | A Passive Center Channel against a Passive Floor-standing - 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. |
A Paradigm 500C B Paradigm Premier 820 v2
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?
Paradigm Premier 820 v2 has the edge on paper, though the margin is not large. The rows marked "depends" may matter more to you than the score does. If a subwoofer is in your plans, the bass gap largely stops mattering - you would be crossing over above 73Hz anyway, so judge these on the other rows instead. In a large or open-plan room, Paradigm Premier 820 v2 has the cabinet volume to fill it more easily; in a small room, near a wall or at desk distance, Paradigm 500C 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.