Short answer: both are discontinued, so this only matters if you are buying used. Used, the MartinLogan Dynamo 1600X is the better pick: it ranks #3 of 212 subwoofers by sound quality (rated 4.2/5), against #119 (rated 3.6/5) for the SVS 20-39 PC-Plus.
The MartinLogan Dynamo 1600X is the better-sounding option. A sealed 15 inch subwoofer with forceful, tight bass, front or down firing setup, and app based room correction, now discontinued. Watch for: Output falls to 86.2dB at 15Hz, so the very lowest effects are weaker than the strong midbass numbers suggest.
What the SVS 20-39 PC-Plus does well: A 12 inch ported cylinder subwoofer that stands tall on a small footprint, now discontinued. Watch for: It stands 1016mm tall and weighs 54.9 lbs (24.9 kg), so it is tall and needs space to clear the port.
Buy the MartinLogan Dynamo 1600X only if you find one used in good condition; both are discontinued, and it is the better rated of the two.
Looking for alternatives? See the complete Subwoofers rankings.
A sealed 15 inch subwoofer with forceful, tight bass, front or down firing setup, and app based room correction, now discontinued.
A 12 inch ported cylinder subwoofer that stands tall on a small footprint, now discontinued.
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Specifications Side By Side
| MartinLogan Dynamo 1600X | SVS 20-39 PC-Plus | |
|---|---|---|
| Price | $1,606.77 Discontinued | $1,399 Discontinued |
| Ranked | #3 of 212 in Medium Home Subwoofers (30-75 lbs) | #119 of 212 in Medium Home Subwoofers (30-75 lbs) |
| Enclosure | sealed | ported, bottom |
| Output SPL at 15 Hz | 86.2 dB | 91.0 dB |
| Output SPL at 20 Hz | 99.4 dB | 102.7 dB |
| Output SPL at 25 Hz | 103.9 dB | 110.3 dB |
| Output SPL at 31.5 Hz | 111.7 dB | 113.0 dB |
| Output SPL at 40 Hz | 118.4 dB | 112.8 dB |
| Output SPL at 50 Hz | 121.0 dB | 113.7 dB |
| Output SPL at 63 Hz | 121.8 dB | 112.0 dB |
| Output SPL at 80 Hz | 121.0 dB | 110.8 dB |
| Output SPL at 100 Hz | 120.2 dB | - |
| Output SPL at 125 Hz | 119.0 dB | - |
| CEA-2010-A Average (40-80Hz) | 120.5 dB | 112.3 dB |
| Dimensions | 20.1”H x 17.9”W x 19.1”D (510.5 x 454.7 x 485.1 mm) | 40”H x 16”W x 16”D (1016.0 x 406.4 x 406.4 mm) |
| Weight | 56 lbs (25.4 kg) | 54.9 lbs (24.9 kg) |
| Warranty | 3 | 5 |
| Cabinet Color | black | - |
| Country | United States | United States |
| Measurement Source | Audioholics | Ilkka Rissanen |
| Frequency Response | 20-200Hz, ±3dB | 16-290Hz |
| Amplifier Power | 900W RMS / 1800W peak | 525W RMS |
| Inputs | RCA (stereo and LFE), XLR (LFE), speaker-level (banana) | - |
| Drivers | 15” (381mm) driver | 12” (305mm) driver |
| 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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