The KEF R400b is rated 3.6/5 for sound quality, #137 of 212 Medium Home Subwoofers (30-75 lbs). See all Subwoofers rankings for every top pick.
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Brand: KEF
#137 KEF R400b: $699 Discontinued eBay
Pros: A compact sealed subwoofer with two opposed 9 inch woofers, styled to match KEF’s R series speakers. The opposed drivers cancel cabinet vibration, and a 500W RMS amplifier drives them. It measures 110.8dB output across the bands tested from 40Hz up and has a listed response of 26-140Hz. It is built to pair visually with KEF R series speakers.
Cons: Output falls off sharply below 40Hz, at 92.7dB at 31.5Hz and 85.8dB at 20Hz, so it lacks the deep bass for big movie effects. It weighs 21.5kg and the 365.8H x 330.2W x 350.5D mm cabinet is not especially small for its output. It is discontinued, so buying means finding one used.
| Amplifier Power | 500W RMS |
|---|---|
| CEA-2010-A Average (40-80Hz) | 110.8 dB (avg of 3/4 bands) |
| Country | United Kingdom |
| Dimensions | 14.4”H x 13”W x 13.8”D (365.8 x 330.2 x 350.5 mm) |
| Drivers | 2x 9” (229mm) driver |
| Enclosure | sealed |
| Frequency Response | 26-140Hz |
| Measurement Source | Brent Butterworth |
| Output SPL at 20 Hz | 85.8 dB |
| Output SPL at 25 Hz | 87.3 dB |
| Output SPL at 31.5 Hz | 92.7 dB |
| Output SPL at 40 Hz | 107.4 dB |
| Output SPL at 50 Hz | 111.5 dB |
| Output SPL at 63 Hz | 113.6 dB |
| Warranty | 5/2/5 |
| Weight | 47.4 lbs (21.5 kg) |
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- Independently measured by Brent Butterworth; the published figures above come from this ASR subwoofer measurement thread.