Short answer: the Monoprice Monolith M-215. It ranks #24 of 143 subwoofers by sound quality, rated 4.4/5, at $1,499.99; the Rythmik F18 ranks #85, rated 4.1/5, and costs $2,344, so there is not much of a tradeoff to weigh.
Buy the Monoprice Monolith M-215. It is rated higher for sound quality than the Rythmik F18 and costs less, so it is the default pick unless a specific strength of the other one matters more to you.
Looking for alternatives? See the complete Subwoofers rankings.
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Specifications Side By Side
| Monoprice Monolith M-215 | Rythmik F18 | |
|---|---|---|
| Price | $1,499.99 | $2,344 |
| Ranked | #24 of 143 in Large Home Subwoofers (Over 75 lbs) | #85 of 143 in Large Home Subwoofers (Over 75 lbs) |
| Enclosure | ported, front | sealed |
| Output SPL at 12.5 Hz | 103.9 dB | 97.4 dB |
| Output SPL at 15 Hz | 113.1 dB | 102.0 dB |
| Output SPL at 20 Hz | 118.9 dB | 106.2 dB |
| Output SPL at 25 Hz | 122.6 dB | 110.9 dB |
| Output SPL at 31.5 Hz | 125.2 dB | 114.3 dB |
| Output SPL at 40 Hz | 126.4 dB | 117.1 dB |
| Output SPL at 50 Hz | 126.1 dB | 119.1 dB |
| Output SPL at 63 Hz | 125.6 dB | 120.5 dB |
| Output SPL at 80 Hz | 125.6 dB | 121.2 dB |
| Output SPL at 100 Hz | 125.7 dB | 121.4 dB |
| Output SPL at 125 Hz | 126.3 dB | 121.4 dB |
| CEA-2010-A Average (40-80Hz) | 125.9 dB | 119.5 dB |
| Dimensions | 42.3”H x 20”W x 27.6”D (1074.4 x 508.0 x 701.0 mm) | 20.5”H x 20.5”W x 21”D (520.7 x 520.7 x 533.4 mm) |
| Weight | 216.1 lbs (98.0 kg) | 115.1 lbs (52.2 kg) |
| Warranty | 5 | 5/3 |
| Cabinet Color | black | black |
| Country | United States | United States |
| Measurement Source | Brent Butterworth | Data-bass |
| Drivers | 2x 15” (381mm) drivers | 18” (457mm) driver |
| Output SPL at 10 Hz | - | 93.7 dB |
| Inputs | - | XLR (2), RCA (line/LFE) |
| XLR Input | - | Yes |
| RCA Input | - | Yes |
| TRS Input | - | No |
| Optical Input | - | No |
| Coaxial Input | - | No |
| USB Input | - | No |
| HDMI Input | - | No |
| AES Input | - | No |
| Aux Input | - | No |
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