Funk Audio Ultra 21.0LX vs Monoprice Monolith 16 THX Ultra

Last updated: August 9, 2026

Short answer: the Monoprice Monolith 16 THX Ultra. It ranks #13 of 97 subwoofers at $2300; the Funk Audio Ultra 21.0LX ranks #14 and costs $9487.26, so there is not much of a tradeoff to weigh.

On the Monoprice Monolith 16 THX Ultra side: 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. Set against that: Heavy at 78 kg and ported design can interact with room acoustics.

Buy the Funk Audio Ultra 21.0LX if the price matters more than the ranking. Buy the Monoprice Monolith 16 THX Ultra if the ranking matters more than the price.

Specifications Side By Side

Funk Audio Ultra 21.0LX Monoprice Monolith 16 THX Ultra
Price$9,487.26$2,300
Ranked#14 of 97 in Large Powered Home Subwoofers (Over 75 lbs)#13 of 97 in Large Powered Home Subwoofers (Over 75 lbs)
Enclosuresealedported, front
Output SPL at 10 Hz99.9 dB-
Output SPL at 12.5 Hz102.3 dB-
Output SPL at 15 Hz108.4 dB107.3 dB
Output SPL at 20 Hz116.6 dB118.4 dB
Output SPL at 25 Hz120.5 dB123.3 dB
Output SPL at 31.5 Hz121.2 dB125.1 dB
Output SPL at 40 Hz125.0 dB126.3 dB
Output SPL at 50 Hz127.2 dB126.5 dB
Output SPL at 63 Hz126.5 dB126.6 dB
Output SPL at 80 Hz126.6 dB126.8 dB
Output SPL at 100 Hz127.6 dB127.2 dB
CEA-2010-A Average (40-80Hz)126.3 dB126.5 dB
Dimensions25.5"H x 24.5"W x 24.0"D (647.7 x 622.3 x 609.6 mm)25.6"H x 22.0"W x 28.1"D (650.2 x 558.8 x 713.7 mm)
Weight145.1 lbs / 65.8 kg171.5 lbs / 77.8 kg
Warranty35
Cabinet Colorwood, customblack
CountryCanadaUnited States
Measurement SourceManufacturerAudioholics
Drivers21" (533mm) driver16" (406mm) driver
Output SPL at 125 Hz-127.6 dB

The Two Speakers In Full

Funk Audio Ultra 21.0LX: $9,487.26

Funk Audio Ultra 21.0LX ranking card

CEA-2010-A Average (40-80Hz)126.3 dB
Cabinet Colorwood, custom
CountryCanada
Dimensions25.5"H x 24.5"W x 24.0"D (647.7 x 622.3 x 609.6 mm)
Drivers21" (533mm) driver
Enclosuresealed
Measurement SourceManufacturer
Output SPL at 10 Hz99.9 dB
Output SPL at 12.5 Hz102.3 dB
Output SPL at 15 Hz108.4 dB
Output SPL at 20 Hz116.6 dB
Output SPL at 25 Hz120.5 dB
Output SPL at 31.5 Hz121.2 dB
Output SPL at 40 Hz125.0 dB
Output SPL at 50 Hz127.2 dB
Output SPL at 63 Hz126.5 dB
Output SPL at 80 Hz126.6 dB
Output SPL at 100 Hz127.6 dB
Warranty3
Weight145.1 lbs / 65.8 kg

Monoprice Monolith 16 THX Ultra: $2,300

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

CEA-2010-A Average (40-80Hz)126.5 dB
Cabinet Colorblack
CountryUnited States
Dimensions25.6"H x 22.0"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

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Product prices and availability were last checked August 9, 2026 at 6:57 AM UTC 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.