The Viper IIA is an upgraded version of the Viper II. The Viper IIA uses two newly designed 220mm cast-frame bass drivers with aluminum cones. These bass drivers operate in perfect piston mode over their whole operating range. The first breakup mode is at 5000 Hz while in the system; the woofer is operated to only 500 Hz. This performance greatly reduces distortion and coloration throughout the full range. Each bass driver is mounted in a separate sealed chamber. Each chamber is a different size in order to provide an improved speed-bandwidth product and a smoother room LF response. The dual woofers provide improved room loading throughout the lower midrange and mid-bass with increased power handling. Both woofers are run in parallel for maximum amplifier control.