Monolith-DF Plus
International Orders
Designed And Manufactured In The UK
Amazon logo   eBay Logo
The New and Awesome Monolith Plus -DF + Subwoofer 500W RMS (1000W Peak) 12" Ported Reflex - £645.45
With a genuine in room response of 15Hz @ -3dB

Introduction:- We are pleased to announce the introduction of the latest version of the Monolith Plus subwoofer. Working with our speaker manufacturer we have designed what we think is a better more dynamic loudspeaker that will improve the overall performance of the Monolith Plus. We have kept the specification as close as possible to the original loudspeaker so as not to lose the musical qualities but have beefed up the speaker to enhance its home cinema pedigree. One of the major upgrades was to reduce the power compression to the voice coil, the engine room of the subwoofer which now has a 3.5" Diameter voice coil and a larger vented pole piece enabling to easily handle whatever content is thrown at it

The Monolith Plus is the upgraded version of our standard Monolith. The upgrade comprises of a 500W amplifier and our latest FAB 12 loudspeaker to give at least an extra +3dB SPL over the standard Monolith for those who require more from their subwoofer. The amplifier is a beefed up version of our 300W Monolith amplifier and boasts a 700VA transformer and 6 MOSFETS to deliver outstanding power and performance. The FAB12 drive unit fits perfectly both electrically and physically into the Monolith system and offers the same tuneful deep bass of the standard Monolith whilst delivering the outstanding SPL levels.

The Amplifier:- At the heart of the Monolith Plus is our B.LAT Amplifier, starting it's life in the original REL Studio and Stentor subwoofer's this amplifier has been continuously refined and now includes an array of features and controls not found on any other subwoofer in this price range. Controls include volume adjustment for both high and low level inputs, low pass frequency contour 40 to 120Hz and a continuous phase adjustment. With all these functions available to hand the Monolith Plus amplifier will allow the end user varied connection options and ease of fine tuning. This amplifier is built here at our UK factory and is rated at 500W RMS and 1000W RMS peak dynamic.

The Monolith Plus amplifier hand built by B.K. Electronics

The Cabinet:- Out of necessity the cabinet has to be large after all we are designing a high SPL and low distortion subwoofer. The cabinet has to be strong, rigid and not colour the sound. So, it's made from 25mm MDF and critically braced. The port has a 100mm internal diameter and is flared both ends to further eliminate port noise.
The Flared Port
The Superb Drive Unit Front
and Back

Drive Unit:- A 300mm / 12" twin magnet drive unit to increase linear excursion, a cast basket for a solid uncoloured projection of sound without ringing and vented pole piece to help reduce power compression.

Coil Construction
Copper Voice Coil
  Coil Former
Polyamide Former
Magnet Composition
Double Stacked 80oz. ferrite magnets
  Core Details
Vented and extended Core
Basket Materials
12-spoke die-cast aluminium Basket
  Cone Composition

Kevlar-reinforced paper cone

Cone Edge Technology
Foam cone edge
  Dust Cap Composition
Dual inverted dust caps
System Type: 95 Litre reflex tuned to 20Hz, cabinet manufactured from veneered 25mm MDF and Critically braced
Distortion: 5% 102dB @ 20Hz
Frequency Response at -3dB: 20Hz / In Room at 15Hz
Amplifier Input / Output Impedance: High Level 100K - Low Level 10K - Balanced 10K
Gain Control Range: 80dB
Drive Unit Impedance: 4 Ohm
Mains Input: 230V / 50Hz
Dimensions: 420D X 604H x 540W
Weight: 48.0kg
Finishes: Black Ash Veneer, Light Oak Veneer and Cheery Veneer
  • 2 Years Warranty
  • True 500W continuous discrete Mosfet amplifier
  • Truly hand built in Great Britain, when we claim hand built we mean hand built, as there are no SMD components or other automatic placement devices.
  • Downward Firing 300mm (12")
  • Continuously variable frequency control
  • Audiophile grade toroidal transformers
  • Gas Tight Neutrik connection for long term consistency of sound quality
  • Separate controls for high and low-level input adjustment
  • Simultaneous connection of high and low level sources
  • Balanced Inputs
  • Thermal Protection
  • Anti Thump
  • ASP automatic speaker protection audibly transparent driver protection
  • 6 x 16A output devices for effortless current control
  • IEC Power Socket
  • Doubled flared port for reduced port noise
Adobe   Click here for the user manual
Credit Card Payment
Visa MC Maestro

Only £645.45 Qty : Monolith Plus -DF Black Check out

Only £687.45 Qty : Monolith Plus -DF Cherry Check out

Only £645.45 Qty : Monolith Plus -DF White Check out

Only £739.95 Qty : Monolith Plus -DF Gloss Black Check out

Only £739.95 Qty : Monolith Plus -DF Gloss White Check out

Only £687.45 Qty : Monolith Plus -DF Walnut Check out

Only £645.45 Qty : Monolith Plus -DF Black Ash Check out

Only £687.45 Qty : Monolith Plus -DF Mahogany Check out

Only £645.45 Qty : Monolith Plus -DF Light Oak Check out
PayPal Payments for the UK Mainland Only
Optional Extra
To Order a 5, 10 or 15M High Level Lead Click HERE
International Orders

Due to Brexit the trading relationship between the UK and EU has changed for further information on how to place an order please contact us via email

(c) 2024 BK Electronics - Unit 1 Comet Way, Southend-On-Sea, Essex SS2 6TR - Tel ; 01702 527572 email

Terms and Conditions / Returns / Privacy