The S-218 requires an active crossover to function correctly – although the choice of filter points is very wide, allowing the user to tailor the response to exactly what is required. Cardioid DSP program settings are also available to create arrays with significant rejection to the rear of the subwoofers.

The robust enclosure is constructed from premium 18mm (3/4”) multi-laminate Birch plywood – rebated, screwed and glued together. The enclosure is finished in black textured paint as standard, however RAL colour matching as well as weather protection options are available if required. Due to the extremely high cone travel available, enclosure rigidity was key in the design – as such the inside of the enclosure, including the enormous port in the centre – are rigidly braced in all dimensions. Runners are provided on the bottom of the enclosure and on one end to protect the paint finish when in use either lying down or stood on-end, and recesses on the top of the enclosure allow stable stacking of arrays. Eight flush bar handles are fitted as standard, and a tough perforated grille backed with acoustically-transparent black mesh protects the drive units from damage, which can be quickly removed for service purposes.  Input is provided from a single Neutrik NLT4 connector on the rear. For ease of movement the S-218 is supplied with tour-grade castors.

The S-218 requires active high/low pass filters and a single amplifier channel, and as such should be used with professional power amplifiers capable of delivering 3000-4500W RMS into a 2 ohm load. For optimal results, the DQ20 Advanced System Amplifier should be used.