KEF R400b Specification
| Enclosure type | Sealed |
| Frequency Response | 26 - 140 Hz |
| Driver | 2 x 225 mm (9 in.) |
| Inputs | L&R, LFE, Speaker Level |
| Amplifier | 2 x 250 W (500 W) built-in Class-D |
| Phase | 0/180 |
| Crossover Frequency | 40 - 140 Hz |
| Weight | 22.4 kg / 49.28 lbs. |
| Dimensions (WxHxD) | 365 x 330 x 351 mm / 14.37 x 12.99 x 13.82 in. |
