The GP15A gets 120 of watts of power from an ultra-efficient built in amplifier. The 15" Woofer delivers deep and detailed bass while the 1" High Frequency driver produces shimmering top end. The back panel of the speaker offers two channels with multiple input options and a superb digital media interface for connecting USB, SD storage devices. The GP15A features Bluetooth for wireless music streaming from your smart phone. Features: Compact, lightweight 2-way active PA speaker 15-inch extended