Monoprice Monolith 16 THX Ultra vs Rythmik FV15HP

Last updated: September 19, 2026

Short answer: the Monoprice Monolith 16 THX Ultra for output, with both needing room gain. The 16-inch ported driver and THX Ultra certification deliver a 126.5dB CEA-2010-A average against the FV15HP’s 122.0dB, though the Monolith is heavy at 78 kg (172 lbs) and its ported design can interact with room acoustics. The Rythmik FV15HP carries a premium price, weighs 52 kg (114.6 lbs) and depends on ported room gain.

Monoprice Monolith 16 THX Ultra vs Rythmik FV15HP

What the Monoprice Monolith 16 THX Ultra gets right: 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 tradeoff: Heavy at 78 kg (172 lbs) and ported design can interact with room acoustics.

On the Rythmik FV15HP side: 15-inch ported driver reaches 122.0dB CEA-2010-A average, matching the output of subwoofers costing significantly more. Set against that: Premium price ($1,770), ported design room gain dependency, and mid-to-large 52 kg (114.6 lbs) footprint.

Buy the Monoprice Monolith 16 THX Ultra. It is rated higher for sound quality, and the $173 you would save on the Rythmik FV15HP does not close the gap.

Want more options? Browse the full Subwoofers rankings.

Buy the Rythmik FV15HP at Rythmik Audio ($2,127) →

Specifications Side By Side

Monoprice Monolith 16 THX Ultra Rythmik FV15HP
Price$2,300$1,770
Ranked#18 of 110 in Large Home Subwoofers (Over 75 lbs)#48 of 110 in Large Home Subwoofers (Over 75 lbs)
Enclosureported, frontported, front
Output SPL at 15 Hz107.3 dB105.1 dB
Output SPL at 20 Hz118.4 dB111.1 dB
Output SPL at 25 Hz123.3 dB116.1 dB
Output SPL at 31.5 Hz125.1 dB120.0 dB
Output SPL at 40 Hz126.3 dB122.5 dB
Output SPL at 50 Hz126.5 dB122.1 dB
Output SPL at 63 Hz126.6 dB121.8 dB
Output SPL at 80 Hz126.8 dB121.4 dB
Output SPL at 100 Hz127.2 dB121.2 dB
Output SPL at 125 Hz127.6 dB121.1 dB
CEA-2010-A Average (40-80Hz)126.5 dB122.0 dB
Dimensions25.6"H x 22"W x 28.1"D (650.2 x 558.8 x 713.7 mm)24.5"H x 18.2"W x 24.2"D (622.3 x 463.5 x 615.9 mm)
Weight171.5 lbs (77.8 kg)115.1 lbs (52.2 kg)
Warranty55/3
Cabinet Colorblackblack, white
CountryUnited StatesUnited States
Measurement SourceAudioholicsAudioholics
Drivers16" (406mm) driver15" (381mm) driver
InputsXLR, RCA, XLR outXLR (2), RCA (line/LFE)
XLR InputYesYes
RCA InputYesYes
TRS InputNoNo
Optical InputNoNo
Coaxial InputNoNo
USB InputNoNo
HDMI InputNoNo
AES InputNoNo
Aux InputNoNo
Output SPL at 12.5 Hz-92.8 dB
Buy the Rythmik FV15HP at Rythmik Audio ($2,127) →

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

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 →

Rythmik FV15HP: $1,770 Rythmik Audio eBay

Rythmik FV15HP ranking card

Pros: 15-inch ported driver reaches 122.0dB CEA-2010-A average, matching the output of subwoofers costing significantly more.

Cons: Premium price ($2127), ported design room gain dependency, and mid-to-large 52 kg footprint.

Full Rythmik FV15HP review and specifications →

AES InputNo
Aux InputNo
CEA-2010-A Average (40-80Hz)122.0 dB
Cabinet Colorblack, white
Coaxial InputNo
CountryUnited States
Dimensions24.5"H x 18.2"W x 24.2"D (622.3 x 463.5 x 615.9 mm)
Drivers15" (381mm) driver
Enclosureported, front
HDMI InputNo
InputsXLR (2), RCA (line/LFE)
Measurement SourceAudioholics
Optical InputNo
Output SPL at 12.5 Hz92.8 dB
Output SPL at 15 Hz105.1 dB
Output SPL at 20 Hz111.1 dB
Output SPL at 25 Hz116.1 dB
Output SPL at 31.5 Hz120.0 dB
Output SPL at 40 Hz122.5 dB
Output SPL at 50 Hz122.1 dB
Output SPL at 63 Hz121.8 dB
Output SPL at 80 Hz121.4 dB
Output SPL at 100 Hz121.2 dB
Output SPL at 125 Hz121.1 dB
RCA InputYes
TRS InputNo
USB InputNo
Warranty5/3
Weight115.1 lbs (52.2 kg)
XLR InputYes
Check current price at Rythmik Audio ($2,127) →Search eBay for Rythmik FV15HP →