R1380T Stylish Bookshelf Speakers Features: Audio inputs: Line In 1, Line In 2 1-inch(25mm) tweeter 4-inch(116mm) mid-bass driver 21W+21W RMS power output Specifications: TWEETER UNIT 1-inch (25mm) Mid-bass Driver 4-inch (116mm) TOTAL POWER OUTPUT 21W+21W FREQUENCY RESPONSE 55Hz-20KHz INPUT Line In 1, Line In 2 INPUT SENSITIVITY Line In1: 750±50mV Line In2: 550±50mV SIGNAL-TO-NOISE RATIO ≥85dB(A) NOISE LEVEL ≤30dB(A)