Short answer: the Power Sound Audio (PSA) TRIAX if sound quality matters most, the Monoprice Monolith 16 THX Ultra if price matters most. The Power Sound Audio (PSA) TRIAX ranks #5 of 110 subwoofers, rated 4.5/5, at $7995. The Monoprice Monolith 16 THX Ultra ranks #18, rated 4.4/5, at $2300, $5695 cheaper.
The case for the Monoprice Monolith 16 THX Ultra: 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. The catch: Heavy at 78 kg (172 lbs) and ported design can interact with room acoustics.
Buy the Monoprice Monolith 16 THX Ultra when the price outweighs sound quality for you, and the Power Sound Audio (PSA) TRIAX when sound quality outweighs the price instead.
Looking for alternatives? See the complete Subwoofers rankings.
Specifications Side By Side
| Monoprice Monolith 16 THX Ultra | Power Sound Audio (PSA) TRIAX | |
|---|---|---|
| Price | $2,300 | $7995 |
| Ranked | #18 of 110 in Large Home Subwoofers (Over 75 lbs) | #5 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 | 119.8 dB |
| Output SPL at 25 Hz | 123.3 dB | 119.8 dB |
| Output SPL at 31.5 Hz | 125.1 dB | 119.8 dB |
| Output SPL at 40 Hz | 126.3 dB | 130.9 dB |
| Output SPL at 50 Hz | 126.5 dB | 130.9 dB |
| Output SPL at 63 Hz | 126.6 dB | 130.9 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 | - |
| CEA-2010-A Average (40-80Hz) | 126.5 dB | 130.9 dB (avg of 3/4 bands) |
| Dimensions | 25.6"H x 22"W x 28.1"D (650.2 x 558.8 x 713.7 mm) | 23.5"H x 31"W x 27.5"D (596.9 x 787.4 x 698.5 mm) |
| Weight | 171.5 lbs (77.8 kg) | 229.9 lbs (104.3 kg) |
| Warranty | 5 | 5 |
| Cabinet Color | black | - |
| Country | United States | United States |
| Measurement Source | Audioholics | Manufacturer |
| Drivers | 16" (406mm) driver | 3x 15" (381mm) driver |
| Inputs | XLR, RCA, XLR out | XLR (balanced, with loop output) |
| XLR Input | Yes | Yes |
| RCA Input | Yes | No |
| 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 |
Related Speaker Comparisons
More worthwhile head-to-heads for Power Sound Audio (PSA) TRIAX:
- JTR Speakers Orbit Shifter PRO vs Power Sound Audio (PSA) TRIAX
- JTR Speakers Orbit Shifter LFU vs Power Sound Audio (PSA) TRIAX
- JTR Speakers Captivator 4000ULF vs Power Sound Audio (PSA) TRIAX
- JTR Speakers Captivator 215PRO vs Power Sound Audio (PSA) TRIAX
- JTR Speakers Captivator S2 vs Power Sound Audio (PSA) TRIAX
Prices on this page were last checked September 23, 2026 at 11:24 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.
As an eBay Partner, we may be compensated if you make a purchase.
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 →
| AES Input | No |
|---|---|
| Aux Input | No |
| CEA-2010-A Average (40-80Hz) | 126.5 dB |
| Cabinet Color | black |
| Coaxial Input | No |
| 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 |
| HDMI Input | No |
| Inputs | XLR, RCA, XLR out |
| Measurement Source | Audioholics |
| Optical Input | No |
| 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 |
| RCA Input | Yes |
| TRS Input | No |
| USB Input | No |
| Warranty | 5 |
| Weight | 171.5 lbs (77.8 kg) |
| XLR Input | Yes |
- 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
- Monoprice Monolith 16 THX Ultra vs Harbottle Audio C24 L2
- Monoprice Monolith 16 THX Ultra vs Funk Audio Ultra 21.0LX
- Monoprice Monolith 16 THX Ultra vs Funk Audio Classic 18.0
- Monoprice Monolith 16 THX Ultra vs JTR Speakers Captivator 2400
- Monoprice Monolith 16 THX Ultra vs Reaction Audio PV-15X
- Monoprice Monolith 16 THX Ultra vs Harbinger V2218S
- Monoprice Monolith 16 THX Ultra vs Danley Sound Labs DTS10
- Monoprice Monolith 16 THX Ultra vs Rythmik FV25HP
- See all 88 comparisons
Power Sound Audio (PSA) TRIAX: $7995 eBay
Pros: Published CEA-2010 specifications list 119.8 dB at 20 Hz and 130.9 dB (avg of 3/4 bands) through 40-80 Hz. The sealed enclosure with 3x 15” (381mm) driver has the headroom for demanding film bass in a large room.
Cons: The 596.9H x 787.4W x 698.5D mm cabinet and 104.3 kg mass make this a serious placement and moving commitment. A sealed cabinet still needs careful placement and calibration to avoid room-mode peaks.
Full Power Sound Audio (PSA) TRIAX review and specifications →
| AES Input | No |
|---|---|
| Aux Input | No |
| CEA-2010-A Average (40-80Hz) | 130.9 dB (avg of 3/4 bands) |
| Coaxial Input | No |
| Country | United States |
| Dimensions | 23.5"H x 31"W x 27.5"D (596.9 x 787.4 x 698.5 mm) |
| Drivers | 3x 15" (381mm) driver |
| Enclosure | sealed |
| HDMI Input | No |
| Inputs | XLR (balanced, with loop output) |
| Measurement Source | Manufacturer |
| Optical Input | No |
| Output SPL at 20 Hz | 119.8 dB |
| Output SPL at 25 Hz | 119.8 dB |
| Output SPL at 31.5 Hz | 119.8 dB |
| Output SPL at 40 Hz | 130.9 dB |
| Output SPL at 50 Hz | 130.9 dB |
| Output SPL at 63 Hz | 130.9 dB |
| RCA Input | No |
| TRS Input | No |
| USB Input | No |
| Warranty | 5 |
| Weight | 229.9 lbs (104.3 kg) |
| XLR Input | Yes |
- Links
- Reviews, Comparisons and Sound Samples
- These figures are manufacturer-specified rather than independently measured.
- Head-to-Head Comparisons
- Power Sound Audio (PSA) TRIAX vs JTR Speakers Captivator 4000ULF
- Power Sound Audio (PSA) TRIAX vs JTR Speakers Captivator 215PRO
- Power Sound Audio (PSA) TRIAX vs JTR Speakers Orbit Shifter LFU
- Power Sound Audio (PSA) TRIAX vs JTR Speakers Orbit Shifter PRO
- Power Sound Audio (PSA) TRIAX vs JTR Speakers Captivator S2
- Power Sound Audio (PSA) TRIAX vs Reaction Audio PV-15X
- Power Sound Audio (PSA) TRIAX vs Monoprice Monolith M-215
- Power Sound Audio (PSA) TRIAX vs Rythmik FV15HP
- See all 14 comparisons