Monoprice Monolith 16 THX Ultra vs JTR Speakers Captivator 118HT

Last updated: September 16, 2026

Short answer: the Monoprice Monolith 16 THX Ultra on measured sound quality, the JTR Speakers Captivator 118HT on price. The Monoprice Monolith 16 THX Ultra ranks #18 of 110 subwoofers at $2300. The JTR Speakers Captivator 118HT ranks #39 at $1995, $305 cheaper.

Monoprice Monolith 16 THX Ultra vs JTR Speakers Captivator 118HT

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 118HT offers: Independent CEA-2010 testing records 112.6 dB at 20 Hz and 122.8 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 762.0H x 508.0W x 571.5D mm cabinet and 58.5 kg mass make this a serious placement and moving commitment. Ported output does not solve room modes, so careful placement and calibration remain essential.

Buy the Monoprice Monolith 16 THX Ultra if sound quality matters more than the price. Buy the JTR Speakers Captivator 118HT if the price matters more than sound quality.

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

Specifications Side By Side

Monoprice Monolith 16 THX Ultra JTR Speakers Captivator 118HT
Price$2,300$1995
Ranked#18 of 110 in Large Home Subwoofers (Over 75 lbs)#39 of 110 in Large Home Subwoofers (Over 75 lbs)
Enclosureported, frontported, front
Output SPL at 15 Hz107.3 dB108.7 dB
Output SPL at 20 Hz118.4 dB112.6 dB
Output SPL at 25 Hz123.3 dB114.8 dB
Output SPL at 31.5 Hz125.1 dB116.6 dB
Output SPL at 40 Hz126.3 dB119.3 dB
Output SPL at 50 Hz126.5 dB122.3 dB
Output SPL at 63 Hz126.6 dB124.6 dB
Output SPL at 80 Hz126.8 dB125.2 dB
Output SPL at 100 Hz127.2 dB125.1 dB
Output SPL at 125 Hz127.6 dB125.4 dB
CEA-2010-A Average (40-80Hz)126.5 dB122.8 dB
Dimensions25.6"H x 22"W x 28.1"D (650.2 x 558.8 x 713.7 mm)30"H x 20"W x 22.5"D (762.0 x 508.0 x 571.5 mm)
Weight171.5 lbs (77.8 kg)129 lbs (58.5 kg)
Warranty55/3
Cabinet Colorblack-
CountryUnited StatesUnited States
Measurement SourceAudioholicsData-bass
Drivers16" (406mm) driver18" (457mm) driver

More top alternatives to Monoprice Monolith 16 THX Ultra:

Prices on this page were last checked September 16, 2026 at 12:41 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 118HT: $1995 eBay

JTR Speakers Captivator 118HT ranking card

Pros: Independent CEA-2010 testing records 112.6 dB at 20 Hz and 122.8 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 762.0H x 508.0W x 571.5D mm cabinet and 58.5 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 JTR Speakers Captivator 118HT review and specifications →

CEA-2010-A Average (40-80Hz)122.8 dB
CountryUnited States
Dimensions30"H x 20"W x 22.5"D (762.0 x 508.0 x 571.5 mm)
Drivers18" (457mm) driver
Enclosureported, front
Measurement SourceData-bass
Output SPL at 15 Hz108.7 dB
Output SPL at 20 Hz112.6 dB
Output SPL at 25 Hz114.8 dB
Output SPL at 31.5 Hz116.6 dB
Output SPL at 40 Hz119.3 dB
Output SPL at 50 Hz122.3 dB
Output SPL at 63 Hz124.6 dB
Output SPL at 80 Hz125.2 dB
Output SPL at 100 Hz125.1 dB
Output SPL at 125 Hz125.4 dB
Warranty5/3
Weight129 lbs (58.5 kg)
Search eBay for JTR Speakers Captivator 118HT →