Short answer: the WW Speaker Cabinets X21 - B&C 21DS115-4. It ranks #3 of 143 subwoofers by sound quality (rated 4.6/5) at $3,995 and is still sold new; the Reaction Audio PV-15X ranks #22 (rated 4.4/5) and is discontinued, so it is only an option used.
The case for the Reaction Audio PV-15X: A passive 15 inch ported subwoofer in a cinema style cabinet with strong output for home theater use, now discontinued. Watch for: Passive design requires a separate external amplifier and weighs 149.9 lbs (68 kg).
What the WW Speaker Cabinets X21 - B&C 21DS115-4 does well: A passive 21 inch ported subwoofer with enormous output, made for big home theater rooms. The catch: Premium $3995 price, massive 114.6 lbs (52 kg) cabinet, and ported room gain dependency.
Buy the WW Speaker Cabinets X21 - B&C 21DS115-4. It is rated higher for sound quality; the Reaction Audio PV-15X is no longer sold new.
Want more options? Browse the full Subwoofers rankings.
A passive 15 inch ported subwoofer in a cinema style cabinet with strong output for home theater use, now discontinued.
A passive 21 inch ported subwoofer with enormous output, made for big home theater rooms.
Prices on this page were last checked October 29, 2026 at 4:42 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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Specifications Side By Side
| Reaction Audio PV-15X | WW Speaker Cabinets X21 - B&C 21DS115-4 | |
|---|---|---|
| Price | $1,999 Passive, Discontinued | $3,995 Passive |
| Ranked | #22 of 143 in Large Home Subwoofers (Over 75 lbs) | #3 of 143 in Large Home Subwoofers (Over 75 lbs) |
| Enclosure | ported, rear | ported, front |
| Output SPL at 15 Hz | 105.3 dB | 111.9 dB |
| Output SPL at 20 Hz | 111.3 dB | 121.9 dB |
| Output SPL at 25 Hz | 116.1 dB | 120.8 dB |
| Output SPL at 31.5 Hz | 119.8 dB | 122.5 dB |
| Output SPL at 40 Hz | 125.3 dB | 126.7 dB |
| Output SPL at 50 Hz | 126.8 dB | 129.2 dB |
| Output SPL at 63 Hz | 126.1 dB | 132.9 dB |
| Output SPL at 80 Hz | 126.5 dB | 136.3 dB |
| Output SPL at 100 Hz | 126.4 dB | 139.0 dB |
| Output SPL at 125 Hz | 126.1 dB | 140.1 dB |
| CEA-2010-A Average (40-80Hz) | 126.2 dB | 131.3 dB |
| Dimensions | 18”H x 22”W x 29”D (457.2 x 558.8 x 736.6 mm) | 24”H x 32”W x 32”D (609.6 x 812.8 x 812.8 mm) |
| Measurement Source | Data-bass | Data-bass |
| Weight | 149.9 lbs (68 kg) | 115.1 lbs (52.2 kg) |
| Drivers | 15” (381mm) driver | 21” (533mm) driver |
| Passive | Yes | Yes |
| Output SPL at 12.5 Hz | - | 96.2 dB |
| Country | - | United States |
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