Monoprice Monolith 8 THX Certified Review: Rated 2.7/5

Last updated: October 21, 2026

The Monoprice Monolith 8 THX Certified is rated 2.7/5 for sound quality, #66 of 73 Small Home Subwoofers (Under 30 lbs). See all Subwoofers rankings for every top pick.

Monoprice Monolith 8 THX Certified · Editor's rating 2.7/5, ranked #66 of 73 Small Home Subwoofers (Under 30 lbs)

Prices on this page were last checked October 29, 2026 at 4:42 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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Brand: Monoprice

#66 Monoprice Monolith 8 THX Certified: $350 Discontinued eBay

Pros: A compact THX certified 8 inch subwoofer with selectable modes, sized for a small room or satellite system. A compact 9kg, ported 8-inch subwoofer with THX certification that can suit a small room or satellite-based system without taking much floor space. Measured output is useful through the upper bass: 99.3dB at 50Hz, 100.7dB at 63Hz and 101.6dB at 80Hz. Its selectable THX/EQ modes provide a more controlled option for music than the extended setting.

Cons: Deep-bass output is modest for a home-theater subwoofer, falling to 72.9dB at 20Hz and 86.1dB at 25Hz. It will not deliver the infrasonic impact or room-filling output of a larger model, and the manufacturer lists it as out of stock. Choose it for compactness and moderate listening levels, not for demanding cinema effects. Discontinued.

Notes: Product # 41289

ReleasedAug 2023 (3 years ago)
CEA-2010-A Average (40-80Hz)99.6 dB
Cabinet Colorblack
CountryUnited States
Dimensions12.6”H x 13.5”W x 12.6”D (319.8 x 342.9 x 319.8 mm)
Drivers8” (203mm) driver
Enclosureported
Measurement SourceErinsAudioCorner
Output SPL at 20 Hz72.9 dB
Output SPL at 25 Hz86.1 dB
Output SPL at 31.5 Hz93.2 dB
Output SPL at 40 Hz96.9 dB
Output SPL at 50 Hz99.3 dB
Output SPL at 63 Hz100.7 dB
Output SPL at 80 Hz101.6 dB
Output SPL at 100 Hz101.9 dB
Weight19.8 lbs (9.0 kg)
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