The WW Speaker Cabinets X21 - B&C 21DS115-4 ranks #3 out of 110 total Large Home Subwoofers (Over 75 lbs) for sound quality. See all Subwoofers rankings for every top pick.

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WW Speaker Cabinets X21 - B&C 21DS115-4 - ranked #3 of 110 Large Home Subwoofers (Over 75 lbs) · Editor's rating 4.6/5

#3 WW Speaker Cabinets X21 - B&C 21DS115-4: $3995 Passive eBay

Pros: 21-inch driver in a large ported cabinet delivers 131.3dB CEA-2010-A average, the highest output of any passive subwoofer tested.

Cons: Premium $3,995 price, massive 52 kg cabinet, and ported room gain dependency.

How it compares: Just above it: JTR Speakers Orbit Shifter LFU - $3000 more, 2.5dB more max output. Just below it: Pro Audio Technology LFC-24sm - $6005 more, 4.2dB more max output.

CEA-2010-A Average (40-80Hz)	131.3 dB
Dimensions	24"H x 32"W x 32"D (609.6 x 812.8 x 812.8 mm)
Drivers	21" (533mm) driver
Enclosure	ported, front
Measurement Source	Data-bass
Output SPL at 12.5 Hz	96.2 dB
Output SPL at 15 Hz	111.9 dB
Output SPL at 20 Hz	121.9 dB
Output SPL at 25 Hz	120.8 dB
Output SPL at 31.5 Hz	122.5 dB
Output SPL at 40 Hz	126.7 dB
Output SPL at 50 Hz	129.2 dB
Output SPL at 63 Hz	132.9 dB
Output SPL at 80 Hz	136.3 dB
Output SPL at 100 Hz	139.0 dB
Output SPL at 125 Hz	140.1 dB
Passive	Yes
Weight	115.1 lbs (52.2 kg)

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Reviews, Comparisons and Sound Samples
- Independently measured by Data-bass; the published figures above come from this ASR subwoofer measurement thread.
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