| Specifications for: KF-CI200QSB-THX: KEF 8" THX Certified Ultra Square Subwoofers – Pair | 
|---|
| Model | Ci200QSb-THX Passive Mode (Crossover "ON") | Ci200QSb-THX Active Mode (KASA500) | 
| Series | Q Series | Q Series | 
| Nominal impedance | 6 Ω | - | 
| Sensitivity (2.83V/1m) | 85dB | - | 
| Frequency response (±6dB) open-backed | 40Hz - 100Hz | 30Hz - 140Hz | 
| Frequency range (-10dB) | 29Hz - 140Hz | 25Hz - KASA setting | 
| Nominal coverage | Not Provided | Not Provided | 
| Max SPL | 104dB | 104dB | 
| Crossover frequency | 100Hz | - | 
| Drive units | LF: 200 mm (8 in.) | LF: 200 mm (8 in.) | 
| Required amplifier | - | KEF KASA500 | 
| Recommended amplifier power | 10 - 150 W | - | 
| Recommended high-pass filter | - | KASA | 
| Recommended low-pass filter | 80Hz - 120Hz | 50Hz - 120Hz | 
| Product external dimensions (H x W x D) | 273 x 273 x 106 mm (10.75 x 10.75 x 4.17 in.) | 273 x 273 x 106 mm (10.75 x 10.75 x 4.17 in.) | 
| Product external dimensions (Diameter ⌀ x Depth) | Not Applicable | Not Applicable | 
| Cut-out dimensions (H x W) | 238 x 238 mm (9.37 x 9.37 in.) | 238 x 238 mm (9.37 x 9.37 in.) | 
| Cut-out dimensions (Diameter ⌀) | Not Applicable | Not Applicable | 
| Net Weight | 3.3 kg (7.28 lbs) | 3.3 kg (7.28 lbs) | 
| Mounting depth from surface | 101.6 mm (4 in.) | 101.6 mm (4 in.) | 
| Optional rough in frame | RIF200S | RIF200S | 
| Optional rear enclosure | Not Provided | Not Provided | 
| Ideal rear volume | 32L per speaker | 32L per speaker | 
| Minimum rear volume | 20L | 20L | 
| Certification | THX ULTRA2, THX SELECT2, IP64 | THX ULTRA2, THX SELECT2, IP64 |