The KSL-GSUB is a high-performance cardioid subwoofer specifically developed for integration into the KSL System, offering enhanced low frequency extension when used with KSL8 and KSL12 loudspeakers. Designed for ground-stacked deployment, the KSL-GSUB is engineered to meet the demands of professional sound reinforcement in environments requiring precise and controlled bass response. Its purpose-built cardioid design enables highly directional low frequency dispersion, significantly reducing unwanted sound radiation to the rear. This is particularly valuable in acoustically sensitive venues or outdoor applications where control over the reverberant field is critical to maintaining audio clarity and reducing noise pollution on stage or in restricted zones. The KSL-GSUB is constructed for durability, with a weather-resistant finish and robust mechanical structure suited to both touring and permanent installations. By delivering accurate and impactful low frequency reproduction, the KSL-GSUB plays an essential role in achieving balanced system performance, improving intelligibility, and enhancing the overall listening experience in large-scale sound applications. It is a vital component for system designers and integrators seeking reliable and predictable low-end reinforcement within a cardioid deployment strategy.