The Guzauski-Swist GS-XED15 Sub System is available when an owner of the Guzauski-Swist GS3A Stereo 2.0 Monitoring System wishes to convert their existing 2.0 Stereo system into a 2.1 system or a 5.1 system. The System is made up of two components: the Guzauski Swist GS-A1 Power Amplifier and the Guzauski Swist XED15 Subwoofer module. All crossover, DSP and bass management processing is done with the Guzauski-Swist GS-XD4080 DSP Processing Module, which is included in the Guzauski-Swist GS3A Stereo 2.0 Monitoring System.