The SW 215E – SP is a highly flexible active plug-and-play subwoofer system for applications in which a powerful and highly differentiated bass reproduction with high sound pressure is needed. While doing so, the SW 215E – SP is also an excellent bass supplement to the passive K&F speakers and the models from the active K&F SP Series. Combinations with the K&F Line 212 systems harmonise extremely well. Using the stacking foot grooves on the top and the side, the Line 212 systems can easily be stacked on top of vertically or horizontally positioned SW 215E – SP. The active system electronics include convection-cooled and highly efficient digital power amplifiers with a total output of 2 kW. They take care over the system equalisation, determine the cut-off frequency, and optimise the phase characteristics. An elaborate limiter section with RMS and peak limiters provides for high operating safety. The optional ‘Suspension’ version of the SW 215E – SP enables not only horizontal but also vertical ‘flying’ of the subwoofer. For a fast and safe set-up, the rigging system ’Click & Fly’ Flyware, which is ‘BG certified’ and compatible to the Line 212 System, is recommendable. The SW 215E – SP is an impressive ‘self powered’ subwoofer with excellent bass reproduction while having extremely compact dimensions and is, therefore, well suited for a wide variety of high-level professional uses.