Dual Sonos-engineered drivers generate deep, dynamic low end. The ported enclosure enhances the bass response and low-frequency output so you feel every beat, roar, and rumble in your chest. Pair Sub Beam for dramatically richer bass, clearer highs and deeper immersion in all your entertainment The acoustic architecture creates a force-cancelling effect that virtually eliminates distortion. Sub 4 so your paired soundbar or speakers can deliver high and mid frequencies with even greater clarity and precision. Trueplayoptimises the sound for the unique acoustics of your space so the bass neeven if you place Sub 4 next to the wall or lying flat and put it under your sofa. Simply plug in the power cable and open the Sonos app to quickly add Sub 4 to your system.