Monoprice Monolith 12 THX Ultra Review: Ranked #94 of 110

Last updated: September 13, 2026

The Monoprice Monolith 12 THX Ultra ranks #94 out of 110 total Large Home Subwoofers (Over 75 lbs) for sound quality. See all Subwoofers rankings for every top pick.

Brand: Monoprice

Prices on this page were last checked September 14, 2026 at 1:47 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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Monoprice Monolith 12 THX Ultra - ranked #94 of 110 Large Home Subwoofers (Over 75 lbs) · Editor's rating 3.8/5

#94 Monoprice Monolith 12 THX Ultra: $1499 eBay

Pros: Independent CEA-2010 testing records 108.4 dB at 20 Hz and 115.2 dB through 40-80 Hz. The ported, front enclosure with 12” (305mm) driver has the headroom for demanding film bass in a large room.

Cons: The 579.1H x 424.2W x 599.4D mm cabinet and 44.7 kg mass make this a serious placement and moving commitment. Ported output does not solve room modes, so careful placement and calibration remain essential.

Notes: Product # 24457

How it compares: Just above it: Arendal 1961 Subwoofer 1V - $299 cheaper. Just below it: Monoprice Monolith M-12 V2 - $599 cheaper.

CEA-2010-A Average (40-80Hz)115.2 dB
Cabinet Colorblack
CountryUnited States
Dimensions22.8"H x 16.7"W x 23.6"D (579.1 x 424.2 x 599.4 mm)
Drivers12" (305mm) driver
Enclosureported, front
Measurement SourceErinsAudioCorner
Output SPL at 12.5 Hz87.7 dB
Output SPL at 15 Hz101.2 dB
Output SPL at 20 Hz108.4 dB
Output SPL at 25 Hz110.9 dB
Output SPL at 31.5 Hz113.0 dB
Output SPL at 40 Hz114.0 dB
Output SPL at 50 Hz115.0 dB
Output SPL at 63 Hz116.0 dB
Output SPL at 80 Hz116.0 dB
Output SPL at 100 Hz115.0 dB
Output SPL at 125 Hz114.0 dB
Warranty5
Weight98.5 lbs (44.7 kg)
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