Short answer: the WW Speaker Cabinets X21 for the highest tested output. Its 21-inch driver in a large ported cabinet delivers a 131.3dB CEA-2010-A average, the highest output of any passive subwoofer tested, against 125.2dB from the Chase SS18.1’s 18-inch sealed driver. The X21 is the heavier option at 52 kg (114.6 lbs) with a premium price and ported room gain dependency, while the Chase is passive and needs external amplification.
On the Chase Home Theater SS18.1 side: 18-inch sealed driver delivers 125.2dB CEA-2010-A average from a dedicated cinema-style sealed cabinet. The tradeoff: Passive design needs external amplification, 41 kg (90.4 lbs) weight, and sealed design room modes.
The case for the WW Speaker Cabinets X21 - B&C 21DS115-4: 21-inch driver in a large ported cabinet delivers 131.3dB CEA-2010-A average, the highest output of any passive subwoofer tested. Set against that: Premium $3,995 price, massive 52 kg (114.6 lbs) cabinet, and ported room gain dependency.
One note: the Chase Home Theater SS18.1 is no longer sold new, but at #32 of 110 subwoofers by sound quality it still outranks most current models, so used is worth considering.
Buy the WW Speaker Cabinets X21 - B&C 21DS115-4. It is rated higher for sound quality, and the $1496 saving on the Chase Home Theater SS18.1 is not enough to make up the difference.
Looking for alternatives? See the complete Subwoofers rankings.
Specifications Side By Side
| Chase Home Theater SS18.1 | WW Speaker Cabinets X21 - B&C 21DS115-4 | |
|---|---|---|
| Price | $2499 Passive, Discontinued | $3995 Passive |
| Ranked | #32 of 110 in Large Home Subwoofers (Over 75 lbs) | #3 of 110 in Large Home Subwoofers (Over 75 lbs) |
| Enclosure | sealed | ported, front |
| Passive | Yes | Yes |
| Output SPL at 12.5 Hz | 92.8 dB | 96.2 dB |
| Output SPL at 15 Hz | 97.2 dB | 111.9 dB |
| Output SPL at 20 Hz | 101.3 dB | 121.9 dB |
| Output SPL at 25 Hz | 106.0 dB | 120.8 dB |
| Output SPL at 31.5 Hz | 111.6 dB | 122.5 dB |
| Output SPL at 40 Hz | 118.2 dB | 126.7 dB |
| Output SPL at 50 Hz | 123.6 dB | 129.2 dB |
| Output SPL at 63 Hz | 128.1 dB | 132.9 dB |
| Output SPL at 80 Hz | 130.8 dB | 136.3 dB |
| Output SPL at 100 Hz | 132.6 dB | 139.0 dB |
| Output SPL at 125 Hz | 133.7 dB | 140.1 dB |
| CEA-2010-A Average (40-80Hz) | 125.2 dB | 131.3 dB |
| Dimensions | 22"H x 24"W x 22"D (558.8 x 609.6 x 558.8 mm) | 24"H x 32"W x 32"D (609.6 x 812.8 x 812.8 mm) |
| Measurement Source | Data-bass | Data-bass |
| Discontinued | Yes | - |
| Weight | 89.9 lbs (40.8 kg) | 115.1 lbs (52.2 kg) |
| Drivers | 18" (457mm) driver | 21" (533mm) driver |
| Country | USA | United States |
Related Speaker Comparisons
How WW Speaker Cabinets X21 - B&C 21DS115-4 compares with other leading options:
- Pro Audio Technology LFC-24sm vs WW Speaker Cabinets X21 - B&C 21DS115-4
- JTR Speakers Captivator S2 vs WW Speaker Cabinets X21 - B&C 21DS115-4
- JTR Speakers Growler (2015) vs WW Speaker Cabinets X21 - B&C 21DS115-4
- Danley Sound Labs DTS10 vs WW Speaker Cabinets X21 - B&C 21DS115-4
- Monoprice Monolith 16 THX Ultra vs WW Speaker Cabinets X21 - B&C 21DS115-4
Prices on this page were last checked September 23, 2026 at 11:24 PM UTC. Product prices and availability are accurate as of that date/time and are subject to change; the price and availability shown on Amazon at the time of purchase will apply to the purchase of this product.
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The Two Speakers In Full
Chase Home Theater SS18.1: $2499 Passive, Discontinued eBay
Pros: 18-inch sealed driver delivers 125.2dB CEA-2010-A average from a dedicated cinema-style sealed cabinet.
Cons: Passive design needs external amplification, 41 kg weight, and sealed design room modes. Discontinued.
Full Chase Home Theater SS18.1 review and specifications →
| CEA-2010-A Average (40-80Hz) | 125.2 dB |
|---|---|
| Country | USA |
| Dimensions | 22"H x 24"W x 22"D (558.8 x 609.6 x 558.8 mm) |
| Discontinued | Yes |
| Drivers | 18" (457mm) driver |
| Enclosure | sealed |
| Measurement Source | Data-bass |
| Output SPL at 12.5 Hz | 92.8 dB |
| Output SPL at 15 Hz | 97.2 dB |
| Output SPL at 20 Hz | 101.3 dB |
| Output SPL at 25 Hz | 106.0 dB |
| Output SPL at 31.5 Hz | 111.6 dB |
| Output SPL at 40 Hz | 118.2 dB |
| Output SPL at 50 Hz | 123.6 dB |
| Output SPL at 63 Hz | 128.1 dB |
| Output SPL at 80 Hz | 130.8 dB |
| Output SPL at 100 Hz | 132.6 dB |
| Output SPL at 125 Hz | 133.7 dB |
| Passive | Yes |
| Weight | 89.9 lbs (40.8 kg) |
- Reviews, Comparisons and Sound Samples
- Independently measured by Data-bass; the published figures above come from this ASR subwoofer measurement thread.
- Head-to-Head Comparisons
- Chase Home Theater SS18.1 vs JBL 4645C
- Chase Home Theater SS18.1 vs Reaction Audio PV-15X
- Chase Home Theater SS18.1 vs Monoprice Monolith 16 THX Ultra
- Chase Home Theater SS18.1 vs Danley Sound Labs DTS10
- Chase Home Theater SS18.1 vs HSU Research VTF-15H MK2
- Chase Home Theater SS18.1 vs JTR Speakers Growler (2015)
- Chase Home Theater SS18.1 vs HSU Research VTF-3 MK5 HP
- Chase Home Theater SS18.1 vs JTR Speakers Captivator S2
- See all 9 comparisons
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 $3995 price, massive 52 kg cabinet, and ported room gain dependency.
Full WW Speaker Cabinets X21 - B&C 21DS115-4 review and specifications →
| CEA-2010-A Average (40-80Hz) | 131.3 dB |
|---|---|
| Country | United States |
| 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) |
- Reviews, Comparisons and Sound Samples
- Independently measured by Data-bass; the published figures above come from this ASR subwoofer measurement thread.
- Head-to-Head Comparisons
- WW Speaker Cabinets X21 - B&C 21DS115-4 vs Pro Audio Technology LFC-24sm
- WW Speaker Cabinets X21 - B&C 21DS115-4 vs JTR Speakers Captivator S2
- WW Speaker Cabinets X21 - B&C 21DS115-4 vs JTR Speakers Growler (2015)
- WW Speaker Cabinets X21 - B&C 21DS115-4 vs Danley Sound Labs DTS10
- WW Speaker Cabinets X21 - B&C 21DS115-4 vs Monoprice Monolith 16 THX Ultra
- WW Speaker Cabinets X21 - B&C 21DS115-4 vs Reaction Audio PV-15X
- WW Speaker Cabinets X21 - B&C 21DS115-4 vs JBL 4645C
- WW Speaker Cabinets X21 - B&C 21DS115-4 vs HSU Research VTF-15H MK2
- See all 9 comparisons