Blackline B218X Subwoofer
Only Available in China

The B218X is a dual-driver, high performance subwoofer for use with full-range loudspeakers. With an operating range of 42Hz-200Hz + 3dB, it produces high output levels with low distortion and can be used singly or stacked horizontally. It features dual 18” (460mm)/4” (100mm) voice coil, long-excursion drivers in a reflex enclosure with eight large ports that reduce air turbulence at high output levels.


  • Dual-driver, direct radiator subwoofer
  • 2 x 18” (460mm) drivers with 4” (100mm) voice coils
  • Durable plywood enclosure
  • Large ports for reduced air noise
  • Powder coated, perforated steel grille
  • Integral ergonomic handles
  • 35mm pole-mount socket
  • Feet for vertical or horizonal operation
  • Rebate recesses for stable horizontal stacking
  • M10 flying inserts


  • Portable sound reinforcement
  • Live music clubs
  • Premium KTV
  • Nightclubs

The B218X enclosure is constructed from plywood and finished in black textured paint.

For added versatility in deployment, the B218X is fitted with a 35mm pole-mount socket for mounting full-range enclosures, and integral M10 inserts provide for eyebolt suspension of a single enclosure.

Ergonomic handles assist ease of handling and the drivers are protected by a perforated steel grille. Rubber feet on the base of the B218X resist movement and align with recesses in the top surface for stable horizontal stacking. Feet are also provided on one side of the enclosure for vertical operation of a single cabinet.

The B218X is supplied as standard without castors, which are available as an accessory pack.

When used with full-range systems, crossover and EQ functions can be performed by the DX0.4, DX0.6 or DX4.0 system controllers or by a Martin Audio amplifier with onboard DSP.

TYPEDual-driver, direct radiating subwoofer
FREQUENCY RESPONSE (5)42Hz-200Hz ± 3dB, -10dB @ 33Hz
DRIVER18” (460mm)/4” (100mm) voice coil, long excursion, ferrite magnet
RATED POWER (2)1600W AES, 6400W peak
MAXIMUM SPL (9)141dB peak (half space)
DISPERSION (-6dB)Omnidirectional
CROSSOVER80-120Hz active
ENCLOSUREBirch/poplar ply
FINISHBlack textured paint
PROTECTIVE GRILLEBlack perforated steel
PIN CONNECTIONS (INPUT)1+ 1- Link Through 2+ 2-
PIN CONNECTIONS (LINK)1+ 1- Link Through 2+ 2-
FITTINGS12 x M10 inserts, pole-mount socket

(W) 1049mm x (H) 587mm x (D) 727mm
(W) 41.3ins x (H) 23.1ins x (D) 28.6ins

WEIGHT88kg (194lbs)
Technical Drawings & 3D Models
Martin AudioB218X Tech Drawing

All information is Copyright. Martin Audio Ltd.

Technical Drawings for B218X



3D SketchUp Models for B218X

none currently available


Revit File 

none currently available

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Copyright Martin Audio Ltd.
Subject to change without notice.
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