Short answer: the Funk Audio Ultra 21.0LX, if you are buying new. The Monoprice Monolith 16 THX Ultra measures as well as it (#19 vs #20 of 143 subwoofers, 4.4/5 vs 4.4/5) but is discontinued, so only consider it used; the Funk Audio Ultra 21.0LX is still sold new at $17,065.
Buy the Funk Audio Ultra 21.0LX, since the Monoprice Monolith 16 THX Ultra is discontinued and only worth hunting down used.
Looking for alternatives? See the complete Subwoofers rankings.
Published CEA-2010 specifications list 116.6 dB at 20 Hz and 126.3 dB through 40-80 Hz.
Funk Audio $17,065 eBay
16-inch ported driver and THX Ultra certification deliver 126.5dB CEA-2010-A average at a fraction of the price of the subwoofers ranked above it.
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Specifications Side By Side
| Funk Audio Ultra 21.0LX | Monoprice Monolith 16 THX Ultra | |
|---|---|---|
| Price | $17,065 | $2,300 Discontinued |
| Ranked | #20 of 143 in Large Home Subwoofers (Over 75 lbs) | #19 of 143 in Large Home Subwoofers (Over 75 lbs) |
| Enclosure | sealed | ported, front |
| Output SPL at 10 Hz | 99.9 dB | - |
| Output SPL at 12.5 Hz | 102.3 dB | - |
| Output SPL at 15 Hz | 108.4 dB | 107.3 dB |
| Output SPL at 20 Hz | 116.6 dB | 118.4 dB |
| Output SPL at 25 Hz | 120.5 dB | 123.3 dB |
| Output SPL at 31.5 Hz | 121.2 dB | 125.1 dB |
| Output SPL at 40 Hz | 125.0 dB | 126.3 dB |
| Output SPL at 50 Hz | 127.2 dB | 126.5 dB |
| Output SPL at 63 Hz | 126.5 dB | 126.6 dB |
| Output SPL at 80 Hz | 126.6 dB | 126.8 dB |
| Output SPL at 100 Hz | 127.6 dB | 127.2 dB |
| CEA-2010-A Average (40-80Hz) | 126.3 dB | 126.5 dB |
| Dimensions | 25.5”H x 24.5”W x 24”D (647.7 x 622.3 x 609.6 mm) | 25.6”H x 22”W x 28.1”D (650.2 x 558.8 x 713.7 mm) |
| Weight | 145.1 lbs (65.8 kg) | 171.5 lbs (77.8 kg) |
| Warranty | 3 | 5 |
| Cabinet Color | wood, custom | black |
| Country | Canada | United States |
| Measurement Source | Manufacturer | Audioholics |
| Drivers | 21” (533mm) driver | 16” (406mm) driver |
| Inputs | XLR (balanced) | XLR, RCA, XLR out |
| XLR Input | Yes | Yes |
| RCA Input | No | 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 |
| Output SPL at 125 Hz | - | 127.6 dB |
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