Short answer: the Monoprice Monolith 16 THX Ultra on measured sound quality, the ELAC SUB3070 on price. The Monoprice Monolith 16 THX Ultra ranks #18 of 110 subwoofers at $2300. The ELAC SUB3070 ranks #34 at $999, $1301 cheaper.
What the Monoprice Monolith 16 THX Ultra offers: 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. Watch for: Heavy at 78 kg and ported design can interact with room acoustics.
What the ELAC SUB3070 offers: Independent CEA-2010 testing records 101.8 dB at 20 Hz and 123.9 dB through 40-80 Hz. The sealed enclosure with 2x 12” (305mm) driver delivers substantial upper-bass output for movie effects and music. Watch for: 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. The 435.1H x 517.9W x 476.2D mm cabinet and 34.9 kg mass still require deliberate placement and calibration.
Buy the Monoprice Monolith 16 THX Ultra when sound quality outweighs the price for you, and the ELAC SUB3070 when the price outweighs sound quality instead.
Still deciding? The full Subwoofers rankings cover every ranked option.
Specifications Side By Side
| Monoprice Monolith 16 THX Ultra | ELAC SUB3070 | |
|---|---|---|
| Price | $2,300 | $999 |
| Ranked | #18 of 110 in Large Home Subwoofers (Over 75 lbs) | #34 of 110 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 | 101.8 dB |
| Output SPL at 25 Hz | 123.3 dB | 105.2 dB |
| Output SPL at 31.5 Hz | 125.1 dB | 110.7 dB |
| Output SPL at 40 Hz | 126.3 dB | 118.0 dB |
| Output SPL at 50 Hz | 126.5 dB | 123.7 dB |
| Output SPL at 63 Hz | 126.6 dB | 127.3 dB |
| Output SPL at 80 Hz | 126.8 dB | 126.5 dB |
| Output SPL at 100 Hz | 127.2 dB | - |
| Output SPL at 125 Hz | 127.6 dB | - |
| CEA-2010-A Average (40-80Hz) | 126.5 dB | 123.9 dB |
| Dimensions | 25.6"H x 22"W x 28.1"D (650.2 x 558.8 x 713.7 mm) | 17.1"H x 20.4"W x 18.7"D (435.1 x 517.9 x 476.2 mm) |
| Weight | 171.5 lbs (77.8 kg) | 76.9 lbs (34.9 kg) |
| Warranty | 5 | 3/1 |
| Cabinet Color | black | black, white, wood |
| Country | United States | Germany |
| Measurement Source | Audioholics | Brent Butterworth |
| Drivers | 16" (406mm) driver | 2x 12" (305mm) driver |
| Output SPL at 16 Hz | - | 98.9 dB |
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Prices on this page were last checked September 16, 2026 at 12:41 AM 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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The Two Speakers In Full
Monoprice Monolith 16 THX Ultra: $2,300 eBay
Pros: 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.
Cons: Heavy at 78 kg and ported design can interact with room acoustics.
Notes: Product # 42031
Full Monoprice Monolith 16 THX Ultra review and specifications →
| CEA-2010-A Average (40-80Hz) | 126.5 dB |
|---|---|
| Cabinet Color | black |
| Country | United States |
| Dimensions | 25.6"H x 22"W x 28.1"D (650.2 x 558.8 x 713.7 mm) |
| Drivers | 16" (406mm) driver |
| Enclosure | ported, front |
| Measurement Source | Audioholics |
| Output SPL at 15 Hz | 107.3 dB |
| Output SPL at 20 Hz | 118.4 dB |
| Output SPL at 25 Hz | 123.3 dB |
| Output SPL at 31.5 Hz | 125.1 dB |
| Output SPL at 40 Hz | 126.3 dB |
| Output SPL at 50 Hz | 126.5 dB |
| Output SPL at 63 Hz | 126.6 dB |
| Output SPL at 80 Hz | 126.8 dB |
| Output SPL at 100 Hz | 127.2 dB |
| Output SPL at 125 Hz | 127.6 dB |
| Warranty | 5 |
| Weight | 171.5 lbs (77.8 kg) |
- Links
- Reviews, Comparisons and Sound Samples
- Independently measured by Audioholics; the published figures above come from this ASR subwoofer measurement thread.
- Head-to-Head Comparisons
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- Monoprice Monolith 16 THX Ultra vs Reaction Audio PV-15X
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ELAC SUB3070: $999 eBay
Pros: Independent CEA-2010 testing records 101.8 dB at 20 Hz and 123.9 dB through 40-80 Hz. The sealed enclosure with 2x 12” (305mm) driver delivers substantial upper-bass output for movie effects and music.
Cons: 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. The 435.1H x 517.9W x 476.2D mm cabinet and 34.9 kg mass still require deliberate placement and calibration.
Full ELAC SUB3070 review and specifications →
| CEA-2010-A Average (40-80Hz) | 123.9 dB |
|---|---|
| Cabinet Color | black, white, wood |
| Country | Germany |
| Dimensions | 17.1"H x 20.4"W x 18.7"D (435.1 x 517.9 x 476.2 mm) |
| Drivers | 2x 12" (305mm) driver |
| Enclosure | sealed |
| Measurement Source | Brent Butterworth |
| Output SPL at 16 Hz | 98.9 dB |
| Output SPL at 20 Hz | 101.8 dB |
| Output SPL at 25 Hz | 105.2 dB |
| Output SPL at 31.5 Hz | 110.7 dB |
| Output SPL at 40 Hz | 118.0 dB |
| Output SPL at 50 Hz | 123.7 dB |
| Output SPL at 63 Hz | 127.3 dB |
| Output SPL at 80 Hz | 126.5 dB |
| Warranty | 3/1 |
| Weight | 76.9 lbs (34.9 kg) |
- Links
- Reviews, Comparisons and Sound Samples
- Independently measured by Brent Butterworth; the published figures above come from this ASR subwoofer measurement thread.
- Head-to-Head Comparisons