Short answer: both are discontinued, and they are rated the same for sound quality (#63 and #62 of 143 subwoofers). Either one is only an option used, so choose on condition and price. If you want one new, the SVS PB17-Ultra R-Evolution replaces the SVS PB16-Ultra and is rated 4.1/5 at $2,999.
What the Monoprice Monolith 13 THX Ultra does well: A THX Ultra certified 13 inch ported subwoofer with deep, strong bass for large rooms at a good price used. The catch: The 604.5H x 515.6W x 739.1D mm cabinet and 153.2 lbs (69.5 kg) mass make this a serious placement and moving commitment.
The case for the SVS PB16-Ultra: A 16 inch ported subwoofer with very strong output down to the lowest notes, great for big home theaters. The catch: The 635.0H x 551.2W x 718.8D mm cabinet and 174.6 lbs (79.2 kg) mass make this a serious placement and moving commitment.
Buy the Monoprice Monolith 13 THX Ultra or the SVS PB16-Ultra, whichever you find used in better condition; both are discontinued. For a new speaker, buy the SVS PB17-Ultra R-Evolution, which replaces the SVS PB16-Ultra.
Want more options? Browse the full Subwoofers rankings.
A THX Ultra certified 13 inch ported subwoofer with deep, strong bass for large rooms at a good price used.
A 16 inch ported subwoofer with very strong output down to the lowest notes, great for big home theaters.
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Specifications Side By Side
| Monoprice Monolith 13 THX Ultra | SVS PB16-Ultra | |
|---|---|---|
| Price | $1,700 Discontinued | $2,900 Discontinued |
| Ranked | #63 of 143 in Large Home Subwoofers (Over 75 lbs) | #62 of 143 in Large Home Subwoofers (Over 75 lbs) |
| Enclosure | ported, front | ported, front |
| Output SPL at 12.5 Hz | 94.0 dB | - |
| Output SPL at 15 Hz | 109.1 dB | 103.0 dB |
| Output SPL at 20 Hz | 115.0 dB | 116.8 dB |
| Output SPL at 25 Hz | 118.0 dB | 119.9 dB |
| Output SPL at 31.5 Hz | 119.5 dB | 122.5 dB |
| Output SPL at 40 Hz | 120.3 dB | 123.3 dB |
| Output SPL at 50 Hz | 120.7 dB | 122.4 dB |
| Output SPL at 63 Hz | 121.4 dB | 120.7 dB |
| Output SPL at 80 Hz | 122.1 dB | 118.6 dB |
| Output SPL at 100 Hz | 122.7 dB | 116.9 dB |
| Output SPL at 125 Hz | 123.8 dB | 115.8 dB |
| CEA-2010-A Average (40-80Hz) | 121.1 dB | 121.2 dB |
| Dimensions | 23.8”H x 20.3”W x 29.1”D (604.5 x 515.6 x 739.1 mm) | 25”H x 21.7”W x 28.3”D (635.0 x 551.2 x 718.8 mm) |
| Weight | 153.2 lbs (69.5 kg) | 174.6 lbs (79.2 kg) |
| Warranty | 5 | 5 |
| Cabinet Color | black | black |
| Country | United States | United States |
| Measurement Source | Audioholics | Audioholics |
| Drivers | 13” (330mm) driver | 16” (406mm) driver with ported design |
| Inputs | XLR (stereo balanced), RCA (stereo/mono) | XLR (balanced), RCA (LFE/stereo) |
| 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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