Short answer: the Monoprice SW-12. It ranks #6 of 212 subwoofers by sound quality, rated 4.2/5, at $364.99; the Klipsch R-121SW ranks #132, rated 3.6/5, and costs $389.99, so there is not much of a tradeoff to weigh.
Buy the Monoprice SW-12. It is rated higher for sound quality than the Klipsch R-121SW and costs less, so only choose the other one for a particular feature it does better.
Still deciding? The full Subwoofers rankings cover every ranked option.
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Specifications Side By Side
| Klipsch R-121SW | Monoprice SW-12 | |
|---|---|---|
| Price | $389.99 | $364.99 |
| Ranked | #132 of 212 in Medium Home Subwoofers (30-75 lbs) | #6 of 212 in Medium Home Subwoofers (30-75 lbs) |
| Enclosure | ported, rear | ported, bottom |
| Output SPL at 15 Hz | 90.7 dB | - |
| Output SPL at 20 Hz | 96.0 dB | 102.7 dB |
| Output SPL at 25 Hz | 98.4 dB | 111.1 dB |
| Output SPL at 31.5 Hz | 102.3 dB | 115.2 dB |
| Output SPL at 40 Hz | 108.2 dB | 119.0 dB |
| Output SPL at 50 Hz | 112.4 dB | 119.7 dB |
| Output SPL at 63 Hz | 112.9 dB | 122.9 dB |
| Output SPL at 80 Hz | 111.3 dB | 123.0 dB |
| Output SPL at 100 Hz | 109.9 dB | - |
| Output SPL at 125 Hz | 108.3 dB | - |
| CEA-2010-A Average (40-80Hz) | 111.2 dB | 121.2 dB |
| Dimensions | 16.6”H x 16”W x 19.7”D (421.6 x 406.4 x 500.4 mm) | 14.9”H x 18.3”W x 19.1”D (378.5 x 464.8 x 485.1 mm) |
| Weight | 35.1 lbs (15.9 kg) | 50.7 lbs (23.0 kg) |
| Warranty | 5/2 | 1 |
| Cabinet Color | black | black |
| Country | United States | United States |
| Measurement Source | Audioholics | Brent Butterworth |
| Amplifier Power | 200W RMS | 400W RMS / 600W peak |
| Frequency Response | 28-120Hz | 35-150Hz, -10dB |
| Drivers | 12” (305mm) driver | 12” (305mm) driver |
| Output SPL at 16 Hz | - | 90.6 dB |
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