Short answer: the Rythmik F18. It ranks #85 of 143 subwoofers by sound quality (rated 4.1/5) at $2,344 and is still sold new; the SVS SB13-Plus ranks #142 (rated 3.3/5) and is discontinued, so it is only an option used.
The Rythmik F18 is the better-sounding pick. A massive sealed 18 inch subwoofer with tight, powerful bass and balanced XLR inputs, built for big home theaters. The catch: The 520.7H x 520.7W x 533.4D mm cabinet and 115.1 lbs (52.2 kg) mass make this a serious placement and moving commitment.
Why pick the SVS SB13-Plus: A sealed 13 inch subwoofer with XLR and RCA inputs in a compact cube cabinet, 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.
Buy the Rythmik F18. It is rated higher for sound quality, and the SVS SB13-Plus is discontinued, so it is only available used.
Looking for alternatives? See the complete Subwoofers rankings.
A massive sealed 18 inch subwoofer with tight, powerful bass and balanced XLR inputs, built for big home theaters.
A sealed 13 inch subwoofer with XLR and RCA inputs in a compact cube cabinet, now discontinued.
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Specifications Side By Side
| Rythmik F18 | SVS SB13-Plus | |
|---|---|---|
| Price | $2,344 | $1,399 Discontinued |
| Ranked | #85 of 143 in Large Home Subwoofers (Over 75 lbs) | #142 of 143 in Large Home Subwoofers (Over 75 lbs) |
| Enclosure | sealed | sealed |
| Output SPL at 10 Hz | 93.7 dB | - |
| Output SPL at 12.5 Hz | 97.4 dB | - |
| Output SPL at 15 Hz | 102.0 dB | - |
| Output SPL at 20 Hz | 106.2 dB | 92.3 dB |
| Output SPL at 25 Hz | 110.9 dB | 97.2 dB |
| Output SPL at 31.5 Hz | 114.3 dB | 97.2 dB |
| Output SPL at 40 Hz | 117.1 dB | 108.1 dB |
| Output SPL at 50 Hz | 119.1 dB | 108.1 dB |
| Output SPL at 63 Hz | 120.5 dB | 108.1 dB |
| Output SPL at 80 Hz | 121.2 dB | - |
| Output SPL at 100 Hz | 121.4 dB | - |
| Output SPL at 125 Hz | 121.4 dB | - |
| CEA-2010-A Average (40-80Hz) | 119.5 dB | 108.1 dB (avg of 3/4 bands) |
| Dimensions | 20.5”H x 20.5”W x 21”D (520.7 x 520.7 x 533.4 mm) | 17”H x 17”W x 18”D (431.8 x 431.8 x 457.2 mm) |
| Weight | 115.1 lbs (52.2 kg) | 95 lbs (43.1 kg) |
| Warranty | 5/3 | 5 |
| Cabinet Color | black | - |
| Country | United States | United States |
| Measurement Source | Data-bass | Brent Butterworth |
| Drivers | 18” (457mm) driver | 13” (330mm) driver |
| Inputs | XLR (2), RCA (line/LFE) | XLR (balanced), RCA |
| 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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