Monoprice Monolith 16 THX Ultra vs SVS PB-4000

Last updated: September 17, 2026

Short answer: the Monoprice Monolith 16 THX Ultra. It ranks #18 of 110 subwoofers by sound quality, rated 4.4/5, at $2300. The SVS PB-4000 ranks #62, rated 4.2/5, at $2158.97, $141.03 cheaper, not enough of a saving to outweigh the sound-quality gap.

Monoprice Monolith 16 THX Ultra vs SVS PB-4000

On the Monoprice Monolith 16 THX Ultra side: 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. It is rated higher for sound quality, and saving $141.03 with the SVS PB-4000 does not make up for the sound-quality gap.

Looking for alternatives? See the complete Subwoofers rankings.

Buy the SVS PB-4000 at Amazon ($2,158.97) →

Specifications Side By Side

Monoprice Monolith 16 THX Ultra SVS PB-4000
Price$2,300$2,158.97
Ranked#18 of 110 in Large Home Subwoofers (Over 75 lbs)#62 of 110 in Large Home Subwoofers (Over 75 lbs)
Enclosureported, frontported, front
Output SPL at 15 Hz107.3 dB102.1 dB
Output SPL at 20 Hz118.4 dB115.3 dB
Output SPL at 25 Hz123.3 dB116.3 dB
Output SPL at 31.5 Hz125.1 dB117.8 dB
Output SPL at 40 Hz126.3 dB119.8 dB
Output SPL at 50 Hz126.5 dB121.7 dB
Output SPL at 63 Hz126.6 dB120.7 dB
Output SPL at 80 Hz126.8 dB119.2 dB
Output SPL at 100 Hz127.2 dB118.1 dB
Output SPL at 125 Hz127.6 dB117.5 dB
CEA-2010-A Average (40-80Hz)126.5 dB120.3 dB
Dimensions25.6"H x 22"W x 28.1"D (650.2 x 558.8 x 713.7 mm)23.4"H x 20.5"W x 27.7"D (594.4 x 520.7 x 703.6 mm)
Weight171.5 lbs (77.8 kg)153.2 lbs (69.5 kg)
Warranty55
Cabinet Colorblackblack
CountryUnited StatesUnited States
Measurement SourceAudioholicsAudioholics
Drivers16" (406mm) driver13.5" (343mm) driver with ported design
InputsXLR, RCA, XLR outXLR (balanced), RCA (LFE/stereo)
XLR InputYesYes
RCA InputYesYes
TRS InputNoNo
Optical InputNoNo
Coaxial InputNoNo
USB InputNoNo
HDMI InputNoNo
AES InputNoNo
Aux InputNoNo
Buy the SVS PB-4000 at Amazon ($2,158.97) →

More top alternatives to Monoprice Monolith 16 THX Ultra:

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 16 THX Ultra: $2,300 eBay

Monoprice Monolith 16 THX Ultra ranking card

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 InputNo
Aux InputNo
CEA-2010-A Average (40-80Hz)126.5 dB
Cabinet Colorblack
Coaxial InputNo
CountryUnited States
Dimensions25.6"H x 22"W x 28.1"D (650.2 x 558.8 x 713.7 mm)
Drivers16" (406mm) driver
Enclosureported, front
HDMI InputNo
InputsXLR, RCA, XLR out
Measurement SourceAudioholics
Optical InputNo
Output SPL at 15 Hz107.3 dB
Output SPL at 20 Hz118.4 dB
Output SPL at 25 Hz123.3 dB
Output SPL at 31.5 Hz125.1 dB
Output SPL at 40 Hz126.3 dB
Output SPL at 50 Hz126.5 dB
Output SPL at 63 Hz126.6 dB
Output SPL at 80 Hz126.8 dB
Output SPL at 100 Hz127.2 dB
Output SPL at 125 Hz127.6 dB
RCA InputYes
TRS InputNo
USB InputNo
Warranty5
Weight171.5 lbs (77.8 kg)
XLR InputYes
Search eBay for Monoprice Monolith 16 THX Ultra →

SVS PB-4000: $2,158.97 Amazon eBay

SVS PB-4000 ranking card

Pros: Independent CEA-2010 testing records 115.3 dB at 20 Hz and 120.3 dB through 40-80 Hz. The ported, front enclosure with 13.5” (343mm) driver with ported design has the headroom for demanding film bass in a large room.

Cons: The 594.4H x 520.7W x 703.6D mm cabinet and 69.5 kg mass make this a serious placement and moving commitment. Ported output does not solve room modes, so careful placement and calibration remain essential.

Full SVS PB-4000 review and specifications →

AES InputNo
Aux InputNo
CEA-2010-A Average (40-80Hz)120.3 dB
Cabinet Colorblack
Coaxial InputNo
CountryUnited States
Dimensions23.4"H x 20.5"W x 27.7"D (594.4 x 520.7 x 703.6 mm)
Drivers13.5" (343mm) driver with ported design
Enclosureported, front
HDMI InputNo
InputsXLR (balanced), RCA (LFE/stereo)
Measurement SourceAudioholics
Optical InputNo
Output SPL at 15 Hz102.1 dB
Output SPL at 20 Hz115.3 dB
Output SPL at 25 Hz116.3 dB
Output SPL at 31.5 Hz117.8 dB
Output SPL at 40 Hz119.8 dB
Output SPL at 50 Hz121.7 dB
Output SPL at 63 Hz120.7 dB
Output SPL at 80 Hz119.2 dB
Output SPL at 100 Hz118.1 dB
Output SPL at 125 Hz117.5 dB
RCA InputYes
TRS InputNo
USB InputNo
Warranty5
Weight153.2 lbs (69.5 kg)
XLR InputYes
Check current price at Amazon ($2,158.97) →Search eBay for SVS PB-4000 →