Short answer: the Rythmik FV15HP. It ranks #55 of 143 subwoofers by sound quality (rated 4.2/5) at $2,127 and is still sold new; the BK Electronics Monolith-DF ranks #141 (rated 3.3/5) and is discontinued, so it is only an option used.
The Rythmik FV15HP is the better-sounding option. A 15 inch ported subwoofer with output matching pricier rivals, plus balanced and RCA inputs for flexible setups. The tradeoff: Premium price ($2127), ported design room gain dependency, and mid-to-large 114.6 lbs (52 kg) footprint.
Why pick the BK Electronics Monolith-DF: A down ported 12 inch subwoofer with balanced XLR and RCA inputs at a low price, now discontinued. The catch: Deep-bass output is more limited than the strong 40-80 Hz result suggests, so it is not the right choice when the lowest movie effects are the priority.
Buy the Rythmik FV15HP. It is rated higher for sound quality, and the BK Electronics Monolith-DF is discontinued, so it is only available used.
Looking for alternatives? See the complete Subwoofers rankings.
A 15 inch ported subwoofer with output matching pricier rivals, plus balanced and RCA inputs for flexible setups.
A down ported 12 inch subwoofer with balanced XLR and RCA inputs at a low price, now discontinued.
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Specifications Side By Side
| Rythmik FV15HP | BK Electronics Monolith-DF | |
|---|---|---|
| Price | $2,127 | £406.95 Discontinued |
| Ranked | #55 of 143 in Large Home Subwoofers (Over 75 lbs) | #141 of 143 in Large Home Subwoofers (Over 75 lbs) |
| Enclosure | ported, front | ported, bottom |
| Output SPL at 12.5 Hz | 92.8 dB | - |
| Output SPL at 15 Hz | 105.1 dB | 91.3 dB |
| Output SPL at 20 Hz | 111.1 dB | 102.0 dB |
| Output SPL at 25 Hz | 116.1 dB | 106.4 dB |
| Output SPL at 31.5 Hz | 120.0 dB | 108.3 dB |
| Output SPL at 40 Hz | 122.5 dB | 108.6 dB |
| Output SPL at 50 Hz | 122.1 dB | 108.7 dB |
| Output SPL at 63 Hz | 121.8 dB | 108.6 dB |
| Output SPL at 80 Hz | 121.4 dB | 107.7 dB |
| Output SPL at 100 Hz | 121.2 dB | - |
| Output SPL at 125 Hz | 121.1 dB | - |
| CEA-2010-A Average (40-80Hz) | 122.0 dB | 108.4 dB |
| Dimensions | 24.5”H x 18.2”W x 24.2”D (622.3 x 463.5 x 615.9 mm) | 23.8”H x 21.3”W x 16.5”D (603.8 x 539.8 x 419.9 mm) |
| Weight | 115.1 lbs (52.2 kg) | 103.2 lbs (46.8 kg) |
| Warranty | 5/3 | 2 |
| Cabinet Color | black, white | black, wood |
| Country | United States | United Kingdom |
| Measurement Source | Audioholics | Ilkka Rissanen |
| Drivers | 15” (381mm) driver | 12” (305mm) driver with ported design |
| Inputs | XLR (2), RCA (line/LFE) | XLR (balanced), RCA (unbalanced) |
| XLR Input | Yes | Yes |
| RCA Input | Yes | Yes |
| TRS Input | No | No |
| Optical Input | No | No |
| Coaxial Input | No | No |
| USB Input | No | No |
| HDMI Input | No | No |
| AES Input | No | No |
| Aux Input | No | No |
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