Monoprice Monolith 12 THX Ultra vs HSU Research VTF-3 MK3

Last updated: September 29, 2026

Short answer: the Monoprice Monolith 12 THX Ultra. It ranks #94 of 109 subwoofers by sound quality, rated 3.8/5, at $1,499; the HSU Research VTF-3 MK3 ranks #97, rated 3.7/5, at $1,499. With prices this close, go by the sound-quality ranking rather than the cost.

Monoprice Monolith 12 THX Ultra vs HSU Research VTF-3 MK3

Why pick the Monoprice Monolith 12 THX Ultra: Independent CEA-2010 testing records 108.4 dB at 20 Hz and 115.2 dB through 40-80 Hz. The tradeoff: The 579.1H x 424.2W x 599.4D mm cabinet and 44.7 kg mass make this a serious placement and moving commitment.

Why pick the HSU Research VTF-3 MK3: Independent CEA-2010 testing records 104.3 dB at 20 Hz and 113.5 dB through 40-80 Hz. Watch for: Deep-bass output is more limited than the strong 40-80 Hz result suggests, so it is not the right choice when the lowest movie effects are the priority.

One note: the Monoprice Monolith 12 THX Ultra is discontinued and no longer widely available new.

Buy the Monoprice Monolith 12 THX Ultra. It is rated higher for sound quality than the HSU Research VTF-3 MK3 at the same price, so it is the default pick unless a specific strength of the other one matters more to you.

Still deciding? The full Subwoofers rankings cover every ranked option.

Specifications Side By Side

Monoprice Monolith 12 THX Ultra HSU Research VTF-3 MK3
Price$1499 Discontinued$1499 Discontinued
Ranked#94 of 109 in Large Home Subwoofers (Over 75 lbs)#97 of 109 in Large Home Subwoofers (Over 75 lbs)
Enclosureported, frontported, rear
Output SPL at 12.5 Hz87.7 dB-
Output SPL at 15 Hz101.2 dB88.5 dB
Output SPL at 20 Hz108.4 dB104.3 dB
Output SPL at 25 Hz110.9 dB108.7 dB
Output SPL at 31.5 Hz113.0 dB109.7 dB
Output SPL at 40 Hz114.0 dB112.1 dB
Output SPL at 50 Hz115.0 dB113.7 dB
Output SPL at 63 Hz116.0 dB114.0 dB
Output SPL at 80 Hz116.0 dB114.0 dB
Output SPL at 100 Hz115.0 dB-
Output SPL at 125 Hz114.0 dB-
CEA-2010-A Average (40-80Hz)115.2 dB113.5 dB
Dimensions22.8”H x 16.7”W x 23.6”D (579.1 x 424.2 x 599.4 mm)21.5”H x 17”W x 25”D (546.1 x 431.8 x 635.0 mm)
Weight98.5 lbs (44.7 kg)89.9 lbs (40.8 kg)
Warranty5-
Cabinet Colorblack-
CountryUnited StatesUnited States
Measurement SourceErinsAudioCornerIlkka Rissanen
Drivers12” (305mm) driver12” (305mm) driver
InputsXLR, RCA, XLR passthrough out-
XLR InputYes-
RCA InputYes-
TRS InputNo-
Optical InputNo-
Coaxial InputNo-
USB InputNo-
HDMI InputNo-
AES InputNo-
Aux InputNo-

How Monoprice Monolith 12 THX Ultra compares with other leading options:

Prices on this page were last checked September 29, 2026 at 3:43 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 12 THX Ultra: $1499 Discontinued eBay

Monoprice Monolith 12 THX Ultra ranking card

Newer model: the Monoprice Monolith M-12 V2, ranked lower, rated 3.8/5 (also discontinued).

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. Discontinued.

Notes: Product # 24457

Full Monoprice Monolith 12 THX Ultra review and specifications →

AES InputNo
Aux InputNo
CEA-2010-A Average (40-80Hz)115.2 dB
Cabinet Colorblack
Coaxial InputNo
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
HDMI InputNo
InputsXLR, RCA, XLR passthrough out
Measurement SourceErinsAudioCorner
Optical InputNo
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
RCA InputYes
TRS InputNo
USB InputNo
Warranty5
Weight98.5 lbs (44.7 kg)
XLR InputYes
Search eBay for Monoprice Monolith 12 THX Ultra →

HSU Research VTF-3 MK3: $1499 Discontinued eBay

HSU Research VTF-3 MK3 ranking card

Newer model: the HSU Research VTF-3 MK5 HP, ranked higher, rated 4.2/5.

Pros: Independent CEA-2010 testing records 104.3 dB at 20 Hz and 113.5 dB through 40-80 Hz. The ported, rear enclosure with 12” (305mm) driver delivers substantial upper-bass output for movie effects and music.

Cons: Deep-bass output is more limited than the strong 40-80 Hz result suggests, so it is not the right choice when the lowest movie effects are the priority. The 546.1H x 431.8W x 635.0D mm cabinet and 40.8 kg mass still require deliberate placement and calibration. Discontinued.

Full HSU Research VTF-3 MK3 review and specifications →

CEA-2010-A Average (40-80Hz)113.5 dB
CountryUnited States
Dimensions21.5”H x 17”W x 25”D (546.1 x 431.8 x 635.0 mm)
Drivers12” (305mm) driver
Enclosureported, rear
Measurement SourceIlkka Rissanen
Output SPL at 15 Hz88.5 dB
Output SPL at 20 Hz104.3 dB
Output SPL at 25 Hz108.7 dB
Output SPL at 31.5 Hz109.7 dB
Output SPL at 40 Hz112.1 dB
Output SPL at 50 Hz113.7 dB
Output SPL at 63 Hz114.0 dB
Output SPL at 80 Hz114.0 dB
Weight89.9 lbs (40.8 kg)
Search eBay for HSU Research VTF-3 MK3 →