Short answer: the WW Speaker Cabinets X21 - B&C 21DS115-4. Both are rated 4.6/5 for sound quality (#3 and #4 of 143 subwoofers), and the WW Speaker Cabinets X21 - B&C 21DS115-4 costs $3,995 against $10,000 for the Pro Audio Technology LFC-24sm, so with nothing between them on sound quality, price settles it.
Buy the WW Speaker Cabinets X21 - B&C 21DS115-4. Both are rated the same for sound quality, and it costs $6,005 less than the Pro Audio Technology LFC-24sm.
Looking for alternatives? See the complete Subwoofers rankings.
Prices on this page were last checked November 7, 2026 at 7:34 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
| Pro Audio Technology LFC-24sm | WW Speaker Cabinets X21 - B&C 21DS115-4 | |
|---|---|---|
| Price | $10,000 Passive | $3,995 Passive |
| Ranked | #4 of 143 in Large Home Subwoofers (Over 75 lbs) | #3 of 143 in Large Home Subwoofers (Over 75 lbs) |
| Enclosure | ported, front | ported, front |
| Passive | Yes | Yes |
| Output SPL at 20 Hz | 123.7 dB | 121.9 dB |
| Output SPL at 25 Hz | 131.4 dB | 120.8 dB |
| Output SPL at 31.5 Hz | 133.6 dB | 122.5 dB |
| Output SPL at 40 Hz | 135.4 dB | 126.7 dB |
| Output SPL at 50 Hz | 136.0 dB | 129.2 dB |
| Output SPL at 63 Hz | 135.2 dB | 132.9 dB |
| CEA-2010-A Average (40-80Hz) | 135.5 dB (avg of 3/4 bands) | 131.3 dB |
| Dimensions | 26”H x 60.5”W x 21”D (660.4 x 1536.7 x 533.4 mm) | 24”H x 32”W x 32”D (609.6 x 812.8 x 812.8 mm) |
| Weight | 266.1 lbs (120.7 kg) | 115.1 lbs (52.2 kg) |
| Cabinet Color | black | - |
| Country | United States | United States |
| Measurement Source | Brent Butterworth | Data-bass |
| Drivers | 24” (610mm) driver | 21” (533mm) driver |
| Output SPL at 12.5 Hz | - | 96.2 dB |
| Output SPL at 15 Hz | - | 111.9 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 |
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