Short answer: the WW Speaker Cabinets X21 for the last decibel, the JTR Growler for about $1,000 less. The X21’s 21-inch driver in a large ported cabinet delivers 131.3dB CEA-2010-A average, the highest output of any passive subwoofer tested. The Growler’s 12-inch ported driver reaches 130.2dB, nearly matching it, though it still brings ported room interaction and a 99.2 lbs (45 kg) frame.
Buy the WW Speaker Cabinets X21 - B&C 21DS115-4. It is rated higher for sound quality; the JTR Speakers Growler (2015) is no longer sold new.
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Specifications Side By Side
| JTR Speakers Growler (2015) | WW Speaker Cabinets X21 - B&C 21DS115-4 | |
|---|---|---|
| Price | $2,995 Passive, Discontinued | $3,995 Passive |
| Ranked | #13 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 | 92.8 dB | 121.9 dB |
| Output SPL at 25 Hz | 97.2 dB | 120.8 dB |
| Output SPL at 31.5 Hz | 106.6 dB | 122.5 dB |
| Output SPL at 40 Hz | 122.7 dB | 126.7 dB |
| Output SPL at 50 Hz | 130.0 dB | 129.2 dB |
| Output SPL at 63 Hz | 133.6 dB | 132.9 dB |
| Output SPL at 80 Hz | 134.4 dB | 136.3 dB |
| Output SPL at 100 Hz | 135.5 dB | 139.0 dB |
| Output SPL at 125 Hz | 136.0 dB | 140.1 dB |
| CEA-2010-A Average (40-80Hz) | 130.2 dB | 131.3 dB |
| Dimensions | 22.5”H x 30”W x 20”D (571.5 x 762.0 x 508.0 mm) | 24”H x 32”W x 32”D (609.6 x 812.8 x 812.8 mm) |
| Country | United States | United States |
| Measurement Source | Data-bass | Data-bass |
| Weight | 100.1 lbs (45.4 kg) | 115.1 lbs (52.2 kg) |
| Drivers | 12” (305mm) driver | 21” (533mm) driver |
| Warranty | 5 years | - |
| Output SPL at 12.5 Hz | - | 96.2 dB |
| Output SPL at 15 Hz | - | 111.9 dB |
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