Monoprice Monolith 16 THX Ultra vs JTR Speakers Captivator 2400ULF

Last updated: September 14, 2026

Short answer: the Monoprice Monolith 16 THX Ultra. It ranks #18 of 110 subwoofers by sound quality at $2300; the JTR Speakers Captivator 2400ULF ranks #40 and costs $3600, so there is not much of a tradeoff to weigh.

Monoprice Monolith 16 THX Ultra vs JTR Speakers Captivator 2400ULF

What the Monoprice Monolith 16 THX Ultra offers: 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. Watch for: Heavy at 78 kg and ported design can interact with room acoustics.

What the JTR Speakers Captivator 2400ULF offers: Independent CEA-2010 testing records 115.6 dB at 20 Hz and 122.7 dB through 40-80 Hz. The ported, front enclosure with 18” (457mm) driver has the headroom for demanding film bass in a large room. Watch for: The 1041.4H x 520.7W x 571.5D mm cabinet and 74.8 kg mass make this a serious placement and moving commitment. Ported output does not solve room modes, so careful placement and calibration remain essential.

Buy the Monoprice Monolith 16 THX Ultra. It ranks higher for sound quality than the JTR Speakers Captivator 2400ULF and costs less, which settles it without a real tradeoff to make.

Looking for alternatives? See the complete Subwoofers rankings.

Specifications Side By Side

Monoprice Monolith 16 THX Ultra JTR Speakers Captivator 2400ULF
Price$2,300$3,600
Ranked#18 of 110 in Large Home Subwoofers (Over 75 lbs)#40 of 110 in Large Home Subwoofers (Over 75 lbs)
Enclosureported, frontported, front
Output SPL at 15 Hz107.3 dB112.2 dB
Output SPL at 20 Hz118.4 dB115.6 dB
Output SPL at 25 Hz123.3 dB117.9 dB
Output SPL at 31.5 Hz125.1 dB121.8 dB
Output SPL at 40 Hz126.3 dB123.3 dB
Output SPL at 50 Hz126.5 dB123.3 dB
Output SPL at 63 Hz126.6 dB122.4 dB
Output SPL at 80 Hz126.8 dB121.6 dB
Output SPL at 100 Hz127.2 dB121.3 dB
Output SPL at 125 Hz127.6 dB121.4 dB
CEA-2010-A Average (40-80Hz)126.5 dB122.7 dB
Dimensions25.6"H x 22"W x 28.1"D (650.2 x 558.8 x 713.7 mm)41"H x 20.5"W x 22.5"D (1041.4 x 520.7 x 571.5 mm)
Weight171.5 lbs (77.8 kg)164.9 lbs (74.8 kg)
Warranty55/3
Cabinet Colorblackblack, custom
CountryUnited StatesUnited States
Measurement SourceAudioholicsData-bass
Drivers16" (406mm) driver18" (457mm) driver
Output SPL at 10 Hz-104.8 dB
Output SPL at 12.5 Hz-109.0 dB

How Monoprice Monolith 16 THX Ultra compares with other leading options:

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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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 →

CEA-2010-A Average (40-80Hz)126.5 dB
Cabinet Colorblack
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
Measurement SourceAudioholics
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
Warranty5
Weight171.5 lbs (77.8 kg)
Search eBay for Monoprice Monolith 16 THX Ultra →

JTR Speakers Captivator 2400ULF: $3,600 eBay

JTR Speakers Captivator 2400ULF ranking card

Pros: Independent CEA-2010 testing records 115.6 dB at 20 Hz and 122.7 dB through 40-80 Hz. The ported, front enclosure with 18” (457mm) driver has the headroom for demanding film bass in a large room.

Cons: The 1041.4H x 520.7W x 571.5D mm cabinet and 74.8 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 JTR Speakers Captivator 2400ULF review and specifications →

CEA-2010-A Average (40-80Hz)122.7 dB
Cabinet Colorblack, custom
CountryUnited States
Dimensions41"H x 20.5"W x 22.5"D (1041.4 x 520.7 x 571.5 mm)
Drivers18" (457mm) driver
Enclosureported, front
Measurement SourceData-bass
Output SPL at 10 Hz104.8 dB
Output SPL at 12.5 Hz109.0 dB
Output SPL at 15 Hz112.2 dB
Output SPL at 20 Hz115.6 dB
Output SPL at 25 Hz117.9 dB
Output SPL at 31.5 Hz121.8 dB
Output SPL at 40 Hz123.3 dB
Output SPL at 50 Hz123.3 dB
Output SPL at 63 Hz122.4 dB
Output SPL at 80 Hz121.6 dB
Output SPL at 100 Hz121.3 dB
Output SPL at 125 Hz121.4 dB
Warranty5/3
Weight164.9 lbs (74.8 kg)
Search eBay for JTR Speakers Captivator 2400ULF →