Short answer: the Monoprice Monolith 16 THX Ultra for better sound quality, the Monoprice Monolith M-12 V2 for the lower price. The Monoprice Monolith 16 THX Ultra ranks #18 of 110 subwoofers at $2300. The Monoprice Monolith M-12 V2 ranks #95 at $900, $1400 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 Monoprice Monolith M-12 V2 offers: 12-inch THX-certified ported with 500W RMS offers excellent value. Delivers very linear response with extension down to 20Hz. Port plug allows sealed configuration for added flexibility. Variable phase and XLR inputs distinguish it from budget offerings. Watch for: No detailed measurement caveats are currently recorded.
Buy the Monoprice Monolith 16 THX Ultra when sound quality outweighs the price for you, and the Monoprice Monolith M-12 V2 when the price outweighs sound quality instead.
If sound quality matters at all to you, skip the Monoprice Monolith M-12 V2. It ranks near the bottom of the 110 subwoofers, so look higher up the list instead.
Want more options? Browse the full Subwoofers rankings.
Specifications Side By Side
| Monoprice Monolith 16 THX Ultra | Monoprice Monolith M-12 V2 | |
|---|---|---|
| Price | $2,300 | $900 |
| Ranked | #18 of 110 in Large Home Subwoofers (Over 75 lbs) | #95 of 110 in Large Home Subwoofers (Over 75 lbs) |
| Enclosure | ported, front | ported, front |
| Output SPL at 15 Hz | 107.3 dB | 99.7 dB |
| Output SPL at 20 Hz | 118.4 dB | 108.3 dB |
| Output SPL at 25 Hz | 123.3 dB | 112.3 dB |
| Output SPL at 31.5 Hz | 125.1 dB | 113.6 dB |
| Output SPL at 40 Hz | 126.3 dB | 114.2 dB |
| Output SPL at 50 Hz | 126.5 dB | 114.6 dB |
| Output SPL at 63 Hz | 126.6 dB | 115.0 dB |
| Output SPL at 80 Hz | 126.8 dB | 115.4 dB |
| Output SPL at 100 Hz | 127.2 dB | 115.9 dB |
| Output SPL at 125 Hz | 127.6 dB | 116.3 dB |
| CEA-2010-A Average (40-80Hz) | 126.5 dB | 114.8 dB |
| Dimensions | 25.6"H x 22"W x 28.1"D (650.2 x 558.8 x 713.7 mm) | 20.9"H x 25.8"W x 16.7"D (530.9 x 655.3 x 424.2 mm) |
| Weight | 171.5 lbs (77.8 kg) | 98.3 lbs (44.6 kg) |
| Warranty | 5 | 5 |
| Cabinet Color | black | black |
| Country | United States | United States |
| Measurement Source | Audioholics | Manufacturer |
| Drivers | 16" (406mm) driver | 12" (305mm) driver |
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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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- Monoprice Monolith 16 THX Ultra vs Danley Sound Labs DTS10
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Monoprice Monolith M-12 V2: $900 eBay
Pros: 12-inch THX-certified ported with 500W RMS offers excellent value. Delivers very linear response with extension down to 20Hz. Port plug allows sealed configuration for added flexibility. Variable phase and XLR inputs distinguish it from budget offerings.
Notes: Product # 42847
Full Monoprice Monolith M-12 V2 review and specifications →
| CEA-2010-A Average (40-80Hz) | 114.8 dB |
|---|---|
| Cabinet Color | black |
| Country | United States |
| Dimensions | 20.9"H x 25.8"W x 16.7"D (530.9 x 655.3 x 424.2 mm) |
| Drivers | 12" (305mm) driver |
| Enclosure | ported, front |
| Measurement Source | Manufacturer |
| Output SPL at 15 Hz | 99.7 dB |
| Output SPL at 20 Hz | 108.3 dB |
| Output SPL at 25 Hz | 112.3 dB |
| Output SPL at 31.5 Hz | 113.6 dB |
| Output SPL at 40 Hz | 114.2 dB |
| Output SPL at 50 Hz | 114.6 dB |
| Output SPL at 63 Hz | 115.0 dB |
| Output SPL at 80 Hz | 115.4 dB |
| Output SPL at 100 Hz | 115.9 dB |
| Output SPL at 125 Hz | 116.3 dB |
| Warranty | 5 |
| Weight | 98.3 lbs (44.6 kg) |
- Links
- Reviews, Comparisons and Sound Samples
- These figures are manufacturer-specified rather than independently measured.