The X SUB 118SA is a processed active subwoofer developed by FBT to deliver extended low-frequency output for professional audio environments. Designed with a focus on both touring and fixed installation applications, the X SUB 118SA features a high-excursion 18-inch woofer equipped with a 75 mm voice coil. The unit is powered by a 1200W Class D amplifier with a switching power supply, enabling consistent and controlled performance across its operating frequency range of 38 Hz to 120 Hz. The inclusion of an advanced DSP processor with four selectable presets allows for precise adaptation to different acoustic requirements, making it suitable for a wide range of configurations. Housed in a robust 18 mm birch plywood cabinet, finished with scratch-resistant paint, the X SUB 118SA ensures long-term durability in demanding environments. It is engineered with practicality in mind, offering an M20 support for pole mounting, aluminium handles for easy handling, and optional 100 mm wheels for enhanced portability. The subwoofer also includes a comprehensive rear control panel, providing stereo XLR inputs and outputs, high-pass filters, volume control, phase adjustment, and LED status indicators. The X SUB 118SA serves as an effective low-frequency extension for FBT’s X Pro and X Lite series loudspeakers, enhancing overall system response in live sound, rental, and fixed sound reinforcement installations.