Short answer: both are discontinued, so this only matters if you are buying used. Used, the HSU Research VTF-3 MK3 is the better pick: it ranks #130 of 143 subwoofers by sound quality (rated 3.7/5), against #141 (rated 3.3/5) for the BK Electronics Monolith-DF. If you want one new, the HSU Research VTF-3 MK5 HP replaces the HSU Research VTF-3 MK3 and is rated 4.2/5 at $1,049.
The HSU Research VTF-3 MK3 is the better-sounding pick. A rear ported 12 inch subwoofer with useful deep bass output for its size, now discontinued. 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.
What the BK Electronics Monolith-DF does well: 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 HSU Research VTF-3 MK3 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, buy the HSU Research VTF-3 MK5 HP, which replaces the HSU Research VTF-3 MK3.
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A rear ported 12 inch subwoofer with useful deep bass output for its size, now discontinued.
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
| HSU Research VTF-3 MK3 | BK Electronics Monolith-DF | |
|---|---|---|
| Price | $1,499 Discontinued | £406.95 Discontinued |
| Ranked | #130 of 143 in Large Home Subwoofers (Over 75 lbs) | #141 of 143 in Large Home Subwoofers (Over 75 lbs) |
| Warranty | 7/2 | 2 |
| Enclosure | ported, rear | ported, bottom |
| Output SPL at 15 Hz | 88.5 dB | 91.3 dB |
| Output SPL at 20 Hz | 104.3 dB | 102.0 dB |
| Output SPL at 25 Hz | 108.7 dB | 106.4 dB |
| Output SPL at 31.5 Hz | 109.7 dB | 108.3 dB |
| Output SPL at 40 Hz | 112.1 dB | 108.6 dB |
| Output SPL at 50 Hz | 113.7 dB | 108.7 dB |
| Output SPL at 63 Hz | 114.0 dB | 108.6 dB |
| Output SPL at 80 Hz | 114.0 dB | 107.7 dB |
| CEA-2010-A Average (40-80Hz) | 113.5 dB | 108.4 dB |
| Dimensions | 21.5”H x 17”W x 25”D (546.1 x 431.8 x 635.0 mm) | 23.8”H x 21.3”W x 16.5”D (603.8 x 539.8 x 419.9 mm) |
| Weight | 89.9 lbs (40.8 kg) | 103.2 lbs (46.8 kg) |
| Country | United States | United Kingdom |
| Measurement Source | Ilkka Rissanen | Ilkka Rissanen |
| Drivers | 12” (305mm) driver | 12” (305mm) driver with ported design |
| Cabinet Color | - | black, wood |
| Inputs | - | XLR (balanced), RCA (unbalanced) |
| 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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