Monoprice Monolith 16 THX Ultra vs JTR Speakers Captivator RS1

Last updated: September 16, 2026

Short answer: the Monoprice Monolith 16 THX Ultra. It ranks #18 of 110 subwoofers by sound quality at $2300; the JTR Speakers Captivator RS1 ranks #49 and costs $3300, so there is not much of a tradeoff to weigh.

Monoprice Monolith 16 THX Ultra vs JTR Speakers Captivator RS1

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 RS1 offers: Independent CEA-2010 testing records 111.1 dB at 20 Hz and 121.8 dB through 40-80 Hz. The sealed enclosure with 18” (457mm) driver has the headroom for demanding film bass in a large room. Watch for: The 533.4H x 533.4W x 457.2D mm cabinet and 53.1 kg mass make this a serious placement and moving commitment. A sealed cabinet still needs careful placement and calibration to avoid room-mode peaks.

Buy the Monoprice Monolith 16 THX Ultra. It ranks higher for sound quality than the JTR Speakers Captivator RS1 and costs less, which settles it without a real tradeoff to make.

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

Specifications Side By Side

Monoprice Monolith 16 THX Ultra JTR Speakers Captivator RS1
Price$2,300$3,300
Ranked#18 of 110 in Large Home Subwoofers (Over 75 lbs)#49 of 110 in Large Home Subwoofers (Over 75 lbs)
Enclosureported, frontsealed
Output SPL at 15 Hz107.3 dB105.4 dB
Output SPL at 20 Hz118.4 dB111.1 dB
Output SPL at 25 Hz123.3 dB115.5 dB
Output SPL at 31.5 Hz125.1 dB119.6 dB
Output SPL at 40 Hz126.3 dB121.3 dB
Output SPL at 50 Hz126.5 dB122.0 dB
Output SPL at 63 Hz126.6 dB122.1 dB
Output SPL at 80 Hz126.8 dB121.9 dB
Output SPL at 100 Hz127.2 dB121.9 dB
Output SPL at 125 Hz127.6 dB121.9 dB
CEA-2010-A Average (40-80Hz)126.5 dB121.8 dB
Dimensions25.6"H x 22"W x 28.1"D (650.2 x 558.8 x 713.7 mm)21"H x 21"W x 18"D (533.4 x 533.4 x 457.2 mm)
Weight171.5 lbs (77.8 kg)117.1 lbs (53.1 kg)
Warranty55/3
Cabinet Colorblackblack
CountryUnited StatesUnited States
Measurement SourceAudioholicsAudioholics
Drivers16" (406mm) driver18" (457mm) driver
Output SPL at 10 Hz-96.1 dB
Output SPL at 12.5 Hz-100.1 dB

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.

As an eBay Partner, we may be compensated if you make a purchase.

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 RS1: $3,300 eBay

JTR Speakers Captivator RS1 ranking card

Pros: Independent CEA-2010 testing records 111.1 dB at 20 Hz and 121.8 dB through 40-80 Hz. The sealed enclosure with 18” (457mm) driver has the headroom for demanding film bass in a large room.

Cons: The 533.4H x 533.4W x 457.2D mm cabinet and 53.1 kg mass make this a serious placement and moving commitment. A sealed cabinet still needs careful placement and calibration to avoid room-mode peaks.

Full JTR Speakers Captivator RS1 review and specifications →

CEA-2010-A Average (40-80Hz)121.8 dB
Cabinet Colorblack
CountryUnited States
Dimensions21"H x 21"W x 18"D (533.4 x 533.4 x 457.2 mm)
Drivers18" (457mm) driver
Enclosuresealed
Measurement SourceAudioholics
Output SPL at 10 Hz96.1 dB
Output SPL at 12.5 Hz100.1 dB
Output SPL at 15 Hz105.4 dB
Output SPL at 20 Hz111.1 dB
Output SPL at 25 Hz115.5 dB
Output SPL at 31.5 Hz119.6 dB
Output SPL at 40 Hz121.3 dB
Output SPL at 50 Hz122.0 dB
Output SPL at 63 Hz122.1 dB
Output SPL at 80 Hz121.9 dB
Output SPL at 100 Hz121.9 dB
Output SPL at 125 Hz121.9 dB
Warranty5/3
Weight117.1 lbs (53.1 kg)
Search eBay for JTR Speakers Captivator RS1 →