Short answer: the Definitive Technology Descend DN15, if you are buying new. The Monoprice Monolith 16 THX Ultra ranks higher than it (#19 vs #132 of 143 subwoofers, 4.4/5 vs 3.7/5) but is discontinued, so only consider it used; the Definitive Technology Descend DN15 is still sold new at $1,439.77.
The Monoprice Monolith 16 THX Ultra is the better-sounding pick. A THX Ultra certified 16 inch ported subwoofer with huge output for far less money than most rivals, now worth finding used. The catch: Heavy at 172 lbs (78 kg) and ported design can interact with room acoustics.
What the Definitive Technology Descend DN15 does well: A 15 inch subwoofer with two passive radiators, very low distortion and bass down to 20Hz. Watch for: Output averages 112.9dB from 40 to 80Hz, which is lower than many other 15 inch subwoofers at this price, so very large rooms may want more headroom.
Buy the Definitive Technology Descend DN15 if you want one new; the Monoprice Monolith 16 THX Ultra is discontinued, so only look for it used.
Still deciding? The full Subwoofers rankings cover every ranked option.
A THX Ultra certified 16 inch ported subwoofer with huge output for far less money than most rivals, now worth finding used.
A 15 inch subwoofer with two passive radiators, very low distortion and bass down to 20Hz.
Prices on this page were last checked October 31, 2026 at 7:11 PM UTC. Product prices and availability are accurate as of that date/time and are subject to change; the price and availability shown on Amazon at the time of purchase will apply to the purchase of this product.
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Specifications Side By Side
| Monoprice Monolith 16 THX Ultra | Definitive Technology Descend DN15 | |
|---|---|---|
| Price | $2,300 Discontinued | $1,439.77 |
| Ranked | #19 of 143 in Large Home Subwoofers (Over 75 lbs) | #132 of 143 in Large Home Subwoofers (Over 75 lbs) |
| Enclosure | ported, front | sealed |
| Output SPL at 15 Hz | 107.3 dB | - |
| Output SPL at 20 Hz | 118.4 dB | 103.9 dB |
| Output SPL at 25 Hz | 123.3 dB | 107.3 dB |
| Output SPL at 31.5 Hz | 125.1 dB | 110.9 dB |
| Output SPL at 40 Hz | 126.3 dB | 113.6 dB |
| Output SPL at 50 Hz | 126.5 dB | 113.5 dB |
| Output SPL at 63 Hz | 126.6 dB | 112.8 dB |
| Output SPL at 80 Hz | 126.8 dB | 111.6 dB |
| Output SPL at 100 Hz | 127.2 dB | 111.0 dB |
| Output SPL at 125 Hz | 127.6 dB | 110.6 dB |
| CEA-2010-A Average (40-80Hz) | 126.5 dB | 112.9 dB |
| Dimensions | 25.6”H x 22”W x 28.1”D (650.2 x 558.8 x 713.7 mm) | 23.4”H x 24.1”W x 24.9”D (595.4 x 613.4 x 632.7 mm) |
| Weight | 171.5 lbs (77.8 kg) | 114.6 lbs (52.0 kg) |
| Warranty | 5 | 5/3 |
| Cabinet Color | black | - |
| Country | United States | United States |
| Measurement Source | Audioholics | Audioholics |
| Drivers | 16” (406mm) driver | 15” driver + 2x 15” passive radiators |
| Inputs | XLR, RCA, XLR out | - |
| 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 | - |
| Output SPL at 12.5 Hz | - | 83.2 dB |
| Output SPL at 16 Hz | - | 97.4 dB |
| Frequency Response | - | 20-150Hz, ±3dB |
| Amplifier Power | - | 500W RMS / 1500W peak |
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