• High efficiency subwoofer with two 18" long-throw woofers with special aligner to maintain performance through the years.
  • Very high power handling (6000 Watts AES peak) and maximum sound pressure (143 dBSPL peak at 1 metre). Also available in high-power self-powered format with the same possible standard performances.
  • The woofers are fitted in separate chambers to ensure operation even in the event of the breakage of one component; it is possible to connect two different signals, stereo and/or the use of two separate amplification channels.
  • Equipped with Outline's proprietary "Fast Hanger" hanging system for fast reasonably priced flying.
  • The cabinet is internally braced to ensure the utmost sturdiness, free from harmful sound "colouring" due to resonance; an optional trolley with sturdy smooth-running wheels facilitates transport, even on relatively uneven surfaces.


  • No-nonsense use in "live" concerts of all sizes, floor or stage mounted and combined with other units of the same type for sound reinforcement of low and ultralow frequencies.
  • High quality permanent indoor or outdoor installations. An ideal match for all Outline loudspeaker systems.


Subtech 218 is a loudspeaker system suited to high-quality sound reinforcement of low and ultra-low frequencies by the use of two by 46 cm. woofers with a special aligner to keep their resonance frequency steady through the years.

Loading is of the phase inversion type with the enclosure tuned at a rather low frequency by a long port with a large surface area. Allowing to obtain a wide passband and a considerable extension towards the bottom end of the frequency response. The performance is very high thanks to the careful choice of the reflex alignment and the construction of the cabinet. The SubTech 218 has a useable frequency range at -10 dB of from 26 Hz to 500 Hz, while the response is just +/-3 dB from 35 Hz to 350 Hz. The max sensitivity is 105 dB in half space and the maximum continuous AES power, 1500W gives 134 dBSPL in free-field and 137 dBSPL in half-space, while peak values even reach 143 dBSPL. The front of the cabinet is protected by an anti-resonant steel grille covered with sound-transparent foam.

\The rectangular cabinet is built in high quality 15mm. Baltic plywood, strengthened by the complex internal structure and suitably positioned internal bracing to eliminate any resonance of the cabinet's sides. The black outer finish is in high quality scratch-resistant paint. The cabinet has 6 fast flying points, that makes vertical or horizontal hanging of numerous units simultaneously extremely easy and reliable, by using the appropriate optional accessories. The front of the enclosure has recessed sockets for fitting an optional trolley, for handling and protecting the front during transport even on uneven surfaces. Ten recessed integrated handles in the side panels of the cabinet are used for a positive grip during handling.


FREQUENCY RESPONSE (-10 dB) 26Hz – 500Hz
(±3 dB) 35Hz – 350Hz
AVERAGE DISPERSION Quasi-Omnidirectional
IMPEDANCE (Ω) Tot (min): 4Ω (3,5 @ 32Hz)
MAX SENSITIVITY (dBSPL 1W 1m) 105 (Half - space)
  1500 6000
MAX DB SPL (peak @ 1 m) Cont. Peak
  137 143
LF 2x18" high-pass vented box
WEIGHT (NET / GROSS) 80 / 88 kg
DIMENSIONS Unit With packing
H x W x D 110 x 65 x 60 cm 117 x 75 x 68 cm