Short answer: both are discontinued, so this only matters if you are buying used. Used, the Genelec HTS4B is the better pick: it ranks #139 of 143 subwoofers by sound quality (rated 3.4/5), against #141 (rated 3.3/5) for the BK Electronics Monolith-DF. If you want one new, the JTR Speakers Orbit Shifter PRO ranks #1 at $4,499.
What the BK Electronics Monolith-DF does well: Independent CEA-2010 testing records 102.0 dB at 20 Hz and 108.4 dB through 40-80 Hz. The tradeoff: 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.
Why pick the Genelec HTS4B: Independent CEA-2010 testing records 97.9 dB at 20 Hz and 110.3 dB through 40-80 Hz. Watch for: 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 Genelec HTS4B only if you find one used in good condition; both are discontinued, and it is the better rated of the two. For a new speaker, start with the JTR Speakers Orbit Shifter PRO instead.
Want more options? Browse the full Subwoofers rankings.
Independent CEA-2010 testing records 102.0 dB at 20 Hz and 108.4 dB through 40-80 Hz.
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Independent CEA-2010 testing records 97.9 dB at 20 Hz and 110.3 dB through 40-80 Hz.
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Specifications Side By Side
| BK Electronics Monolith-DF | Genelec HTS4B | |
|---|---|---|
| Price | £406.95 Discontinued | $2,995 Discontinued |
| Ranked | #141 of 143 in Large Home Subwoofers (Over 75 lbs) | #139 of 143 in Large Home Subwoofers (Over 75 lbs) |
| Enclosure | ported, bottom | passive radiator |
| Output SPL at 15 Hz | 91.3 dB | 92.1 dB |
| Output SPL at 20 Hz | 102.0 dB | 97.9 dB |
| Output SPL at 25 Hz | 106.4 dB | 100.2 dB |
| Output SPL at 31.5 Hz | 108.3 dB | 103.3 dB |
| Output SPL at 40 Hz | 108.6 dB | 107.3 dB |
| Output SPL at 50 Hz | 108.7 dB | 110.1 dB |
| Output SPL at 63 Hz | 108.6 dB | 111.6 dB |
| Output SPL at 80 Hz | 107.7 dB | 112.3 dB |
| CEA-2010-A Average (40-80Hz) | 108.4 dB | 110.3 dB |
| Dimensions | 23.8”H x 21.3”W x 16.5”D (603.8 x 539.8 x 419.9 mm) | 20.4”H x 19”W x 18.3”D (517.4 x 482.6 x 465.1 mm) |
| Weight | 103.2 lbs (46.8 kg) | 81.6 lbs (37.0 kg) |
| Warranty | 2 | 2(+3) |
| Cabinet Color | black, wood | - |
| Country | United Kingdom | Finland |
| Measurement Source | Ilkka Rissanen | Ilkka Rissanen |
| Drivers | 12” (305mm) driver with ported design | 12” (305mm) driver |
| Inputs | XLR (balanced), RCA (unbalanced) | XLR (in plus link-out), RCA (line-level) |
| 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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