Short answer: the HSU Research ULS-15 MK2 if bass quality is the priority, the Klipsch R-121SW if it is price. The HSU’s sealed cabinet delivers tight, accurate bass with low bloat and ranks #4 of 212 subwoofers, at $999. The Klipsch ranks #132 but costs $609.01 less, and its 12-inch spun-copper driver with a 200W RMS amplifier gives controlled, musical bass with minimal distortion.
Buy the HSU Research ULS-15 MK2. It is rated higher for sound quality, and the $609.01 saving on the Klipsch R-121SW is not enough to make up the difference.
Still deciding? The full Subwoofers rankings cover every ranked option.
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Specifications Side By Side
| HSU Research ULS-15 MK2 | Klipsch R-121SW | |
|---|---|---|
| Price | $999.00 | $389.99 |
| Ranked | #4 of 212 in Medium Home Subwoofers (30-75 lbs) | #132 of 212 in Medium Home Subwoofers (30-75 lbs) |
| Enclosure | sealed | ported, rear |
| Output SPL at 12.5 Hz | 93.7 dB | - |
| Output SPL at 15 Hz | 98.0 dB | 90.7 dB |
| Output SPL at 20 Hz | 102.4 dB | 96.0 dB |
| Output SPL at 25 Hz | 107.7 dB | 98.4 dB |
| Output SPL at 31.5 Hz | 113.4 dB | 102.3 dB |
| Output SPL at 40 Hz | 118.3 dB | 108.2 dB |
| Output SPL at 50 Hz | 120.8 dB | 112.4 dB |
| Output SPL at 63 Hz | 121.2 dB | 112.9 dB |
| Output SPL at 80 Hz | 121.1 dB | 111.3 dB |
| Output SPL at 100 Hz | 120.7 dB | 109.9 dB |
| Output SPL at 125 Hz | 120.7 dB | 108.3 dB |
| CEA-2010-A Average (40-80Hz) | 120.3 dB | 111.2 dB |
| Dimensions | 19”H x 18”W x 19.5”D (482.6 x 457.2 x 495.3 mm) | 16.6”H x 16”W x 19.7”D (421.6 x 406.4 x 500.4 mm) |
| Weight | 65 lbs (29.5 kg) | 35.1 lbs (15.9 kg) |
| Warranty | 7/2(+3) | 5/2 |
| Cabinet Color | black, wood | black |
| Country | United States | United States |
| Measurement Source | Audioholics | Audioholics |
| Frequency Response | 20-200Hz, ±1dB | 28-120Hz |
| Amplifier Power | 600W RMS / 2000W peak | 200W RMS |
| Crossover Frequency | 30-90Hz adjustable | - |
| Phase Control | 0°-180° | - |
| Features | Q control, sealed subwoofer, EQ1/EQ2 modes | - |
| Drivers | 15” (381mm) driver | 12” (305mm) driver |
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