SX SeriesInstalled SoundLive Sound


18" Passive Cardioid Portable Subwoofer

SXC118 Compact, High Performance Cardioid Subwoofer
Where to Buy or Rent

Designed for touring sound and installations, the SXC118 is a compact, high performance cardioid subwoofer. It features an 18” (460mm) forward facing driver and a 14” (356mm) rear facing driver, each driven independently by separate amplifier channels and DSP.


  • Compact, cardioid subwoofer
  • Front facing 18” (460mm)/4” (100mm) voice coil driver
  • Rear facing 14” (356mm)/3.5” (88mm) voice coil driver
  • Cardioid dispersion pattern
  • 28dB rear rejection at 75Hz
  • High output capability
  • Tour-grade plywood enclosure with flying inserts


  • Live sound reinforcement
  • Fixed installations including live event venues and nightclubs
  • Theatre sound
  • Corporate AV events
  • Acoustically-challenging rooms
  • Outdoor restaurant, bar and hotel entertainment areas
  • Concourses and Theme Parks

Each driver has its own chamber with optimised bass reflex porting. This arrangement produces a cardioid dispersion pattern which maximises the front radiation and reduces unwanted radiation behind the subwoofer.

SXC118 Internal View
SXC118 Internal View

The recommended iK42 amplifier optimises the DSP parameters for front and rear drivers to maximise the rear rejection — from 21dB at 43Hz to 28dB at 75Hz. This keeps low frequencies away from stages, turntables and walls as well as reducing reverberant energy in the room, greatly improving the system’s low frequency response accuracy and impact.

In front of the enclosure, the output from the two drivers is additive, giving an extra 2dB of output when compared with a conventional 1 x 18” subwoofer.

The enclosure is constructed from plywood and finished with a hard-wearing textured paint. It is equipped with four grab handles and foam-backed perforated steel grilles protect the front and rear drivers. It can be used individually, stacked or flown individually by means of threaded flying inserts

The SXC118 is an ideal partner for WPM and WPS line arrays or our range of point source loudspeakers where low frequency pattern control is required. Interlocking skids prevent movement when stacked and a threaded plate in the top surface facilitates pole- mounting of up to 4 WPM enclosures or a singular point source enclosure. The product is supplied as standard without castors but they can be purchased as an accessory.

By adding the input board cover accessory, the subwoofer is fully weather resistant and suitable for permanent outdoor usage.

User guide Brochure Datasheet
TYPECompact, cardioid subwoofer
FREQUENCY RESPONSE (1) 43Hz – 150Hz ±3dB, -10dB @ 34Hz
  • 18” (460mm)/4” (100mm) voice coil, long excursion, ferrite magnet, waterproof cone
  • 14” (356mm)/3.5” (88mm) voice coil, long excursion, neodymium magnet, waterproof cone
  • 18”: 1000W AES, 4000W peak
  • 14”: 800W AES, 3200W peak
MAXIMUM SPL (9) 140dB peak
  • 18”: 8Ω
  • 14”: 8Ω
DISPERSION (-6dB) Cardioid
ENCLOSURE Multi-laminate birch and poplar ply
FINISH Textured black paint
PROTECTIVE GRILLE Black HEX perforated steel
PIN CONNECTIONS (INPUT) 18”: +1, -1; 14”: +2, -2
PINS CONNECTIONS (LINK) 18”: +1, -1; 14”: +2, -2
  • Two skids on base, with mating channels on top
  • M20 top-mounted thread plate for pole mounting
  • Two bar handles on each side
  • Four fittings for optional transit cover
  • 16 x M10 Mounting Points
  • 16 x M8 inserts for optional castors
  • Two bar handles on each side
  • (W) 650mm x (H) 603mm x (D) 812mm (940mm incl castors)
  • (W) 25.6in x (H) 23.7in x (D) 32in (37in incl castors)
  • 69kg (152lbs)
  • 73kg (161lbs) incl castors
Architectural Specs
Martin Audio SXC118

The loudspeaker shall be a compact cardioid subwoofer consisting of an 18” reflex-loaded transducer radiating to the front of the enclosure and a 14” reflex-loaded transducer radiating to the rear. The transducers shall be driven independently by separate channels of a dedicated controller amplifier.

Power handling of the 18” transducer shall be 1000W AES, 4000W peak. Power handling of the 14” transducer shall be 800W AES, 3200W peak. Rated impedance of each transducer shall be 8 ohms. The on-axis frequency response shall be 43Hz-150kHz +/- 3dB and the loudspeaker shall produce a maximum SPL of 140dB peak calculated at 1 metre.

The loudspeaker enclosure shall be constructed from multi-laminate plywood with a textured coating. The drivers shall be protected by a perforated steel grille and the enclosure shall be fitted with a threaded pole-mount plate, bar handles, skids and flying inserts. The rear connector panel shall be fitted with two NL4 type connectors.

Dimensions including skids, excluding castors (W x H x D) shall be 635mm x 603mm x 824mm (25in x 23.7in x 32.4in). Dimensions including skids and optional castors (W x H x D) shall be 635mm x 603mm x 952mm (25in x 23.7in x 37.5in). Weight excluding castors shall be 69kg (152lbs). Weight including optional castors shall be 73kg (161lbs).

The loudspeaker shall be the Martin Audio SXC118.

Available in this Series

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