BK Electronics Monolith-DF vs Funk Audio Classic 18.0

Last updated: October 13, 2026

Short answer: the Funk Audio Classic 18.0. It ranks #17 of 143 subwoofers by sound quality (rated 4.4/5) at $9,875 and is still sold new; the BK Electronics Monolith-DF ranks #141 (rated 3.3/5) and is discontinued, so it is only an option used.

BK Electronics Monolith-DF vs Funk Audio Classic 18.0

What the BK Electronics Monolith-DF does well: Independent CEA-2010 testing records 102.0 dB at 20 Hz and 108.4 dB through 40-80 Hz. The tradeoff: Deep-bass output is more limited than the strong 40-80 Hz result suggests, so it is not the right choice when the lowest movie effects are the priority.

The Funk Audio Classic 18.0 is the better-sounding choice. Independent CEA-2010 testing records 106.5 dB at 20 Hz and 127.3 dB through 40-80 Hz. Watch for: Deep-bass output is more limited than the strong 40-80 Hz result suggests, so it is not the right choice when the lowest movie effects are the priority.

Buy the Funk Audio Classic 18.0. It is rated higher for sound quality and still sold new, while the BK Electronics Monolith-DF is discontinued.

Want more options? Browse the full Subwoofers rankings.

Check Funk Audio Classic 18.0 price at Funk Audio ($9,875) →

Specifications Side By Side

BK Electronics Monolith-DF Funk Audio Classic 18.0
Price£406.95 Discontinued$9,875
Ranked#141 of 143 in Large Home Subwoofers (Over 75 lbs)#17 of 143 in Large Home Subwoofers (Over 75 lbs)
Enclosureported, bottomsealed
Output SPL at 15 Hz91.3 dB102.3 dB
Output SPL at 20 Hz102.0 dB106.5 dB
Output SPL at 25 Hz106.4 dB111.7 dB
Output SPL at 31.5 Hz108.3 dB119.0 dB
Output SPL at 40 Hz108.6 dB124.6 dB
Output SPL at 50 Hz108.7 dB126.8 dB
Output SPL at 63 Hz108.6 dB128.4 dB
Output SPL at 80 Hz107.7 dB129.6 dB
CEA-2010-A Average (40-80Hz)108.4 dB127.3 dB
Dimensions23.8”H x 21.3”W x 16.5”D (603.8 x 539.8 x 419.9 mm)22.5”H x 22”W x 20.5”D (571.5 x 558.8 x 520.7 mm)
Weight103.2 lbs (46.8 kg)115.1 lbs (52.2 kg)
Warranty23
Cabinet Colorblack, woodwood, custom
CountryUnited KingdomCanada
Measurement SourceIlkka RissanenData-bass
Drivers12” (305mm) driver with ported design18” (457mm) driver
InputsXLR (balanced), RCA (unbalanced)XLR (balanced, with daisy-chain)
XLR InputYesYes
RCA InputYesNo
TRS InputNoNo
Optical InputNoNo
Coaxial InputNoNo
USB InputNoNo
HDMI InputNoNo
AES InputNoNo
Aux InputNoNo
Output SPL at 10 Hz-94.6 dB
Output SPL at 12.5 Hz-98.4 dB
Output SPL at 100 Hz-130.2 dB
Output SPL at 125 Hz-130.8 dB
Check Funk Audio Classic 18.0 price at Funk Audio ($9,875) →

How Funk Audio Classic 18.0 compares with other leading options:

Prices on this page were last checked October 14, 2026 at 2:38 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

BK Electronics Monolith-DF: £406.95 Discontinued eBay

BK Electronics Monolith-DF ranking card

Pros: Independent CEA-2010 testing records 102.0 dB at 20 Hz and 108.4 dB through 40-80 Hz. The ported, bottom enclosure with 12” (305mm) driver with ported design delivers substantial upper-bass output for movie effects and music.

Cons: Deep-bass output is more limited than the strong 40-80 Hz result suggests, so it is not the right choice when the lowest movie effects are the priority. The 603.8H x 539.8W x 419.9D mm cabinet and 46.8 kg mass still require deliberate placement and calibration. Discontinued.

Full BK Electronics Monolith-DF review and specifications →

AES InputNo
Aux InputNo
CEA-2010-A Average (40-80Hz)108.4 dB
Cabinet Colorblack, wood
Coaxial InputNo
CountryUnited Kingdom
Dimensions23.8”H x 21.3”W x 16.5”D (603.8 x 539.8 x 419.9 mm)
Drivers12” (305mm) driver with ported design
Enclosureported, bottom
HDMI InputNo
InputsXLR (balanced), RCA (unbalanced)
Measurement SourceIlkka Rissanen
Optical InputNo
Output SPL at 15 Hz91.3 dB
Output SPL at 20 Hz102.0 dB
Output SPL at 25 Hz106.4 dB
Output SPL at 31.5 Hz108.3 dB
Output SPL at 40 Hz108.6 dB
Output SPL at 50 Hz108.7 dB
Output SPL at 63 Hz108.6 dB
Output SPL at 80 Hz107.7 dB
RCA InputYes
TRS InputNo
USB InputNo
Warranty2
Weight103.2 lbs (46.8 kg)
XLR InputYes
Search eBay for BK Electronics Monolith-DF →

Funk Audio Classic 18.0: $9,875 Funk Audio $9,875 eBay

Funk Audio Classic 18.0 ranking card

Same family: the Funk Audio Classic 21.0L (larger subwoofer, ranked lower, rated 4.2/5).

Pros: Independent CEA-2010 testing records 106.5 dB at 20 Hz and 127.3 dB through 40-80 Hz. The sealed enclosure with 18” (457mm) driver delivers formidable upper-bass output for movie effects and music.

Cons: Deep-bass output is more limited than the strong 40-80 Hz result suggests, so it is not the right choice when the lowest movie effects are the priority. The 571.5H x 558.8W x 520.7D mm cabinet and 52.2 kg mass still require deliberate placement and calibration.

Notes: Data-bass labeled this sub as ‘FW18.0’, but original name is 18.0

Full Funk Audio Classic 18.0 review and specifications →

AES InputNo
Aux InputNo
CEA-2010-A Average (40-80Hz)127.3 dB
Cabinet Colorwood, custom
Coaxial InputNo
CountryCanada
Dimensions22.5”H x 22”W x 20.5”D (571.5 x 558.8 x 520.7 mm)
Drivers18” (457mm) driver
Enclosuresealed
HDMI InputNo
InputsXLR (balanced, with daisy-chain)
Measurement SourceData-bass
Optical InputNo
Output SPL at 10 Hz94.6 dB
Output SPL at 12.5 Hz98.4 dB
Output SPL at 15 Hz102.3 dB
Output SPL at 20 Hz106.5 dB
Output SPL at 25 Hz111.7 dB
Output SPL at 31.5 Hz119.0 dB
Output SPL at 40 Hz124.6 dB
Output SPL at 50 Hz126.8 dB
Output SPL at 63 Hz128.4 dB
Output SPL at 80 Hz129.6 dB
Output SPL at 100 Hz130.2 dB
Output SPL at 125 Hz130.8 dB
RCA InputNo
TRS InputNo
USB InputNo
Warranty3
Weight115.1 lbs (52.2 kg)
XLR InputYes
Check current price at Funk Audio ($9,875) →Search eBay for Funk Audio Classic 18.0 →