High-power subwoofer



Highly efficient, powerful low-frequency loudspeaker fitted with two 18″ transducers
Exceptional size-to-power ratio (148.5 dB SPL short-term peak @ 1 m) facilitates location
Proprietary Outline design provides tremendous ‘punch’
Outline ‘E.R.P.’ (‘Energy Retentive Porting’) design assists airflow and enhances transducer efficiency
Finished with Polyurea, featuring amazing durability and superior physical properties
Design file for Outline ‘Openarray’ 3D acoustic simulation software


This all-new design from Outline complements the existing EIDOS installation range by providing a unit whose low-frequency extension and power handling capabilities exceed those of the dual-15″ EIDOS 215 S module. Consequently it is ideal for those applications requiring super-powerful sub bass delivery, including live music and dance venues.

The EIDOS 218 S is particularly well-suited to reproducing modern dance music as the design provides not only extended low-frequency reproduction (down to 28 Hz) but also tremendous ‘punch’ in and around the frequencies normally produced by both real and synthetic bass drums. This focus and clarity not only enhances the reproduction of program material but also makes the most efficient use of amplifier power.

This is a result of Outline’s proprietary ‘E.R.P.’ (‘Energy Retentive Porting’) design. Based on the principles of fluid dynamics and successfully applied to the science of controlling pneumatic forces within a loudspeaker enclosure, this unique arrangement of specially-shaped ports ensures an optimum laminar airflow. This reduces internal turbulence, maximising the efficiency of the transducers and thus allowing more amplifier power to be converted into acoustic energy.

Such a design requires high-precision manufacturing techniques, and Outline’s engineering team have applied some original production techniques to turn an exciting concept into a physical reality.


Frequency Response (-10 dB) 28 Hz – 250 Hz
Suggested Cross-Over max 120 Hz
Nominal Dispersion Quasi-Omnidirectional
Impedance (Nom/Min) 2 x 8 Ω / 2 x 5.5 Ω
Watt AES (Continuous/Peak) 2 x 1200 W / 2 x 4800 W
Maximum SPL Output * 148.5 dB SPL


Component 2 x 18″ direct radiation woofers
Connectors 2 x NL4 Pins 1+/1-, 2+/2-
Cabinet Material Baltic birch plywood
Cabinet Finish Black polyurea coating
Grill Epoxy powder coated
Installation Points 16 x M8 threaded points
Pole Mount M20 threaded point
Height 570 mm – 22 4/8″
Width 1140 mm – 44 7/8″
Depth 730 mm – 28 6/8″
Weight 85 kg – 187.4 lb


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