Monoprice Monolith M15-S vs Power Sound Audio (PSA) TRIAX

Last updated: September 17, 2026

Short answer: the Power Sound Audio (PSA) TRIAX on measured sound quality, the Monoprice Monolith M15-S on price. The Power Sound Audio (PSA) TRIAX ranks #5 of 110 subwoofers, rated 4.5/5, at $7995. The Monoprice Monolith M15-S ranks #72, rated 4.1/5, at $999, $6996 cheaper.

Monoprice Monolith M15-S vs Power Sound Audio (PSA) TRIAX

Buy the Monoprice Monolith M15-S if the price matters more than sound quality. Buy the Power Sound Audio (PSA) TRIAX if sound quality matters more than the price.

Looking for alternatives? See the complete Subwoofers rankings.

Specifications Side By Side

Monoprice Monolith M15-S Power Sound Audio (PSA) TRIAX
Price$999$7995
Ranked#72 of 110 in Large Home Subwoofers (Over 75 lbs)#5 of 110 in Large Home Subwoofers (Over 75 lbs)
Enclosuresealedsealed
Output SPL at 15 Hz100.1 dB-
Output SPL at 20 Hz105.6 dB119.8 dB
Output SPL at 25 Hz111.2 dB119.8 dB
Output SPL at 31.5 Hz115.2 dB119.8 dB
Output SPL at 40 Hz118.4 dB130.9 dB
Output SPL at 50 Hz119.3 dB130.9 dB
Output SPL at 63 Hz119.6 dB130.9 dB
Output SPL at 80 Hz118.9 dB-
Output SPL at 100 Hz119.1 dB-
Output SPL at 125 Hz118.9 dB-
CEA-2010-A Average (40-80Hz)119.0 dB130.9 dB (avg of 3/4 bands)
Dimensions23.5"H x 16.7"W x 19.7"D (596.9 x 424.2 x 500.4 mm)23.5"H x 31"W x 27.5"D (596.9 x 787.4 x 698.5 mm)
Warranty55
CountryUnited StatesUnited States
Measurement SourceManufacturerManufacturer
Weight80 lbs (36.3 kg)229.9 lbs (104.3 kg)
Drivers15" (381mm) driver3x 15" (381mm) driver
Inputs-XLR (balanced, with loop output)
XLR Input-Yes
RCA Input-No
TRS Input-No
Optical Input-No
Coaxial Input-No
USB Input-No
HDMI Input-No
AES Input-No
Aux Input-No

More worthwhile head-to-heads for 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.

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The Two Speakers In Full

Monoprice Monolith M15-S: $999 eBay

Monoprice Monolith M15-S ranking card

Pros: Published CEA-2010 specifications list 105.6 dB at 20 Hz and 119.0 dB through 40-80 Hz. The sealed enclosure with 15” (381mm) driver has the headroom for demanding film bass in a large room.

Cons: The 596.9H x 424.2W x 500.4D mm cabinet and 36.3 kg mass make this a serious placement and moving commitment. A sealed cabinet still needs careful placement and calibration to avoid room-mode peaks.

Notes: Product # 35141

Full Monoprice Monolith M15-S review and specifications →

CEA-2010-A Average (40-80Hz)119.0 dB
CountryUnited States
Dimensions23.5"H x 16.7"W x 19.7"D (596.9 x 424.2 x 500.4 mm)
Drivers15" (381mm) driver
Enclosuresealed
Measurement SourceManufacturer
Output SPL at 15 Hz100.1 dB
Output SPL at 20 Hz105.6 dB
Output SPL at 25 Hz111.2 dB
Output SPL at 31.5 Hz115.2 dB
Output SPL at 40 Hz118.4 dB
Output SPL at 50 Hz119.3 dB
Output SPL at 63 Hz119.6 dB
Output SPL at 80 Hz118.9 dB
Output SPL at 100 Hz119.1 dB
Output SPL at 125 Hz118.9 dB
Warranty5
Weight80 lbs (36.3 kg)
Search eBay for Monoprice Monolith M15-S →

Power Sound Audio (PSA) TRIAX: $7995 eBay

Power Sound Audio (PSA) TRIAX ranking card

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 InputNo
Aux InputNo
CEA-2010-A Average (40-80Hz)130.9 dB (avg of 3/4 bands)
Coaxial InputNo
CountryUnited States
Dimensions23.5"H x 31"W x 27.5"D (596.9 x 787.4 x 698.5 mm)
Drivers3x 15" (381mm) driver
Enclosuresealed
HDMI InputNo
InputsXLR (balanced, with loop output)
Measurement SourceManufacturer
Optical InputNo
Output SPL at 20 Hz119.8 dB
Output SPL at 25 Hz119.8 dB
Output SPL at 31.5 Hz119.8 dB
Output SPL at 40 Hz130.9 dB
Output SPL at 50 Hz130.9 dB
Output SPL at 63 Hz130.9 dB
RCA InputNo
TRS InputNo
USB InputNo
Warranty5
Weight229.9 lbs (104.3 kg)
XLR InputYes
Search eBay for Power Sound Audio (PSA) TRIAX →