Monoprice Monolith 16 THX Ultra vs Reaction Audio PV-15X

Last updated: September 19, 2026

Short answer: the Monoprice Monolith 16 THX Ultra, since it edges the PV-15X on output and needs no separate amp. The 16-inch ported driver and THX Ultra certification deliver a 126.5dB CEA-2010-A average against the PV-15X’s 126.2dB, though it is heavy at 78 kg (172 lbs) and its ported design can interact with room acoustics. The Reaction Audio PV-15X is passive, so it requires a separate external amplifier, and it weighs 68 kg (149.9 lbs).

Monoprice Monolith 16 THX Ultra vs Reaction Audio PV-15X

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 Reaction Audio PV-15X side: 15-inch ported driver delivers 126.2dB CEA-2010-A average from a purpose-built cinema-style cabinet. The tradeoff: Passive design requires a separate external amplifier and weighs 68 kg (149.9 lbs).

Buy the Monoprice Monolith 16 THX Ultra, since the Reaction Audio PV-15X is discontinued and only worth hunting down used.

Looking for alternatives? See the complete Subwoofers rankings.

Specifications Side By Side

Monoprice Monolith 16 THX Ultra Reaction Audio PV-15X
Price$2,300$1999 Discontinued
Ranked#18 of 110 in Large Home Subwoofers (Over 75 lbs)#21 of 110 in Large Home Subwoofers (Over 75 lbs)
Enclosureported, frontported, rear
Output SPL at 15 Hz107.3 dB105.3 dB
Output SPL at 20 Hz118.4 dB111.3 dB
Output SPL at 25 Hz123.3 dB116.1 dB
Output SPL at 31.5 Hz125.1 dB119.8 dB
Output SPL at 40 Hz126.3 dB125.3 dB
Output SPL at 50 Hz126.5 dB126.8 dB
Output SPL at 63 Hz126.6 dB126.1 dB
Output SPL at 80 Hz126.8 dB126.5 dB
Output SPL at 100 Hz127.2 dB126.4 dB
Output SPL at 125 Hz127.6 dB126.1 dB
CEA-2010-A Average (40-80Hz)126.5 dB126.2 dB
Dimensions25.6"H x 22"W x 28.1"D (650.2 x 558.8 x 713.7 mm)18"H x 22"W x 29"D (457.2 x 558.8 x 736.6 mm)
Weight171.5 lbs (77.8 kg)149.9 lbs (68 kg)
Warranty5-
Cabinet Colorblack-
CountryUnited States-
Measurement SourceAudioholicsData-bass
Drivers16" (406mm) driver15" (381mm) driver
InputsXLR, RCA, XLR out-
XLR InputYes-
RCA InputYes-
TRS InputNo-
Optical InputNo-
Coaxial InputNo-
USB InputNo-
HDMI InputNo-
AES InputNo-
Aux InputNo-
Discontinued-Yes

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 →

Reaction Audio PV-15X: $1999 Discontinued eBay

Reaction Audio PV-15X ranking card

Pros: 15-inch ported driver delivers 126.2dB CEA-2010-A average from a purpose-built cinema-style cabinet.

Cons: Passive design requires a separate external amplifier and weighs 68 kg. Discontinued.

Full Reaction Audio PV-15X review and specifications →

CEA-2010-A Average (40-80Hz)126.2 dB
Dimensions18"H x 22"W x 29"D (457.2 x 558.8 x 736.6 mm)
DiscontinuedYes
Drivers15" (381mm) driver
Enclosureported, rear
Measurement SourceData-bass
Output SPL at 15 Hz105.3 dB
Output SPL at 20 Hz111.3 dB
Output SPL at 25 Hz116.1 dB
Output SPL at 31.5 Hz119.8 dB
Output SPL at 40 Hz125.3 dB
Output SPL at 50 Hz126.8 dB
Output SPL at 63 Hz126.1 dB
Output SPL at 80 Hz126.5 dB
Output SPL at 100 Hz126.4 dB
Output SPL at 125 Hz126.1 dB
Weight149.9 lbs (68 kg)
Search eBay for Reaction Audio PV-15X →