Features 10" cone driver, 250W Amplifier, 20 to 160 Hz frequency range... * 10" cone driver * 250W Amplifier * 20 to 160 Hz frequency range * Advanced Active Servo Technology --is an amplifier/speaker system utilizing negative impedance feedback in the amp and a Helmholtz resonator in the speaker to provide strong and accurate bass. * BASS Selector * Yamaha's QD-Bass Technology * Magnetic…