Front view — side by side at true scale
ACastle Richmond IVBPolk Reserve R100
Click either cabinet to swap A ↔ B · Reference height: 324 mm (32.4 cm) · 1 mm = 1.73 px
| A | B | |
|---|---|---|
| Manufacturer | Castle | Polk |
| Model | Castle Richmond IV | Polk Reserve R100 |
| Height | 305 mm | 324 mm |
| Width | 190 mm | 167 mm |
| Depth | 262 mm | 260 mm |
| Weight | 6.3 kg | 5.5 kg |
| Enclosure | bass-reflex-rear | bass-reflex-rear |
| Drivers | 1× 150 mm mid-bass, 1× 32 mm tweeter (soft dome) | 1× 25 mm tweeter (Pinnacle ring radiator), 1× 133 mm mid-bass (Turbine cone) |
| Frequency — low | 58 Hz | 58 Hz |
| Frequency — high | 22000 Hz | 39000 Hz |
| Sensitivity | 87 dB | 86 dB |
| Impedance | 8 Ω | 4 Ω |
| Recommended amp | 25–100 W | 30–150 W |
| MAP (USD) | $760 / pair | $699 / pair |
| Where to buy | Check availability ↗ | Check availability ↗ |
| Brand website | castle.uk.com ↗ | polkaudio.com ↗ |
| Product page | Open product page ↗ | Open product page ↗ |
Larger value highlighted in green. For low-frequency extension, lower Hz = greater bass reach, so the deeper side is highlighted.