The integrated Fosi BT30D Pro amplifier features two sets of passive speaker outputs and one set of passive subwoofer outputs, making it easy to set up a 2.1 home theatre or other stereo hi-fi audio system. Equipped with two high-quality Texas Instruments TPA3255 Class D amplifier chips, the Bluetooth amplifier delivers clear and pure sound without distortion or clipping with a stable output of up to 165W x 2 + 350W power. Whether you're a gamer, film fan or music lover, this amplifier offers tight, smooth and natural sounding bass. It has two dedicated controls for subwoofer control: the SUB FREQ control allows precise frequency adjustment of passive subwoofers from 0 to 300 Hz, while the SUB VOL control lets you set the desired volume. This gives you full control over the bass output to suit your personal preferences and listening environment.