Features: 4 ways input: 3.5mm AUX, USB, Coaxial, Optical. Subwoofer and 4-wire signal output. LCD shows input source, tone state, volume and remote control receiving. With remote controller to control the effects conveniently. Short press power button to select the input source. (AUX, USB, Coaxial or Optical) Short press volume button for tone control. High-quality aluminum alloy case, exquisite and durable.