Monoprice Monolith 16 THX Ultra vs Definitive Technology Descend DN15

Last updated: September 16, 2026

Short answer: the Monoprice Monolith 16 THX Ultra on measured sound quality, the Definitive Technology Descend DN15 on price. The Monoprice Monolith 16 THX Ultra ranks #18 of 110 subwoofers at $2300. The Definitive Technology Descend DN15 ranks #99 at $1999, $301 cheaper.

Monoprice Monolith 16 THX Ultra vs Definitive Technology Descend DN15

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 Definitive Technology Descend DN15 offers: Independent CEA-2010 testing records 103.9 dB at 20 Hz and 112.9 dB through 40-80 Hz. The sealed enclosure pairs a 15” long-throw woofer with dual 15” passive radiators for very low distortion and true 20Hz extension. Watch for: Output tops out lower than other large subwoofers in this price range, and there’s no XLR input.

Buy the Monoprice Monolith 16 THX Ultra when sound quality outweighs the price for you, and the Definitive Technology Descend DN15 when the price outweighs sound quality instead.

The Definitive Technology Descend DN15 is not a sound-quality pick. It sits near the bottom of the 110 subwoofers; there are better options higher up.

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

Buy the Definitive Technology Descend DN15 at Amazon ($1,999.00) →

Specifications Side By Side

Monoprice Monolith 16 THX Ultra Definitive Technology Descend DN15
Price$2,300$1,999.00
Ranked#18 of 110 in Large Home Subwoofers (Over 75 lbs)#99 of 110 in Large Home Subwoofers (Over 75 lbs)
Enclosureported, frontsealed
Output SPL at 15 Hz107.3 dB-
Output SPL at 20 Hz118.4 dB103.9 dB
Output SPL at 25 Hz123.3 dB107.3 dB
Output SPL at 31.5 Hz125.1 dB110.9 dB
Output SPL at 40 Hz126.3 dB113.6 dB
Output SPL at 50 Hz126.5 dB113.5 dB
Output SPL at 63 Hz126.6 dB112.8 dB
Output SPL at 80 Hz126.8 dB111.6 dB
Output SPL at 100 Hz127.2 dB111.0 dB
Output SPL at 125 Hz127.6 dB110.6 dB
CEA-2010-A Average (40-80Hz)126.5 dB112.9 dB
Dimensions25.6"H x 22"W x 28.1"D (650.2 x 558.8 x 713.7 mm)23.4"H x 24.1"W x 24.9"D (595.4 x 613.4 x 632.7 mm)
Weight171.5 lbs (77.8 kg)114.6 lbs (52.0 kg)
Warranty5-
Cabinet Colorblack-
CountryUnited StatesUnited States
Measurement SourceAudioholicsAudioholics
Drivers16" (406mm) driver15" driver + 2x 15" passive radiators
Output SPL at 12.5 Hz-83.2 dB
Output SPL at 16 Hz-97.4 dB
Frequency Response-20-150Hz, ±3dB
Amplifier Power-500W RMS / 1500W peak
Buy the Definitive Technology Descend DN15 at Amazon ($1,999.00) →

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 →

Definitive Technology Descend DN15: $1,999.00 Amazon eBay

Definitive Technology Descend DN15 ranking card

Pros: Independent CEA-2010 testing records 103.9 dB at 20 Hz and 112.9 dB through 40-80 Hz. The sealed enclosure pairs a 15” long-throw woofer with dual 15” passive radiators for very low distortion and true 20Hz extension.

Cons: Output tops out lower than other large subwoofers in this price range, and there’s no XLR input.

Full Definitive Technology Descend DN15 review and specifications →

Amplifier Power500W RMS / 1500W peak
CEA-2010-A Average (40-80Hz)112.9 dB
CountryUnited States
Dimensions23.4"H x 24.1"W x 24.9"D (595.4 x 613.4 x 632.7 mm)
Drivers15" driver + 2x 15" passive radiators
Enclosuresealed
Frequency Response20-150Hz, ±3dB
Measurement SourceAudioholics
Output SPL at 12.5 Hz83.2 dB
Output SPL at 16 Hz97.4 dB
Output SPL at 20 Hz103.9 dB
Output SPL at 25 Hz107.3 dB
Output SPL at 31.5 Hz110.9 dB
Output SPL at 40 Hz113.6 dB
Output SPL at 50 Hz113.5 dB
Output SPL at 63 Hz112.8 dB
Output SPL at 80 Hz111.6 dB
Output SPL at 100 Hz111.0 dB
Output SPL at 125 Hz110.6 dB
Weight114.6 lbs (52.0 kg)
Check current price at Amazon ($1,999.00) →Search eBay for Definitive Technology Descend DN15 →