The Italian Stage S118A 18" Active Subwoofer is ideal for adding powerful yet smooth bass to your live setup. It uses a 18" woofer driven by a 350W RMS class AB amplifier, resulting in 129 peak SPL and a 20Hz to 120Hz frequency range. This results in a booming bass sound, that matches precise performance with a punchy sound. The S118A also has a control panel section, with controls for line level, a phase switch, crossover switch - activating a high pass filter for outputs - as well as ground switch.