... to noise ratio.3. All new design of switching power circuit can transfer 18V DC electric current up ot 110V or ... ,advanced double surface SMT circuit9.Built-in DVD player ,FM radio receiver,can play DVD,VCD,CD,MP3,MP4 disc10.USB,SD ... be inserted flash memory card,MP3,MP411.Built-in advanced receiver modular system with two wireless mics (handheld ,lavalier ,and clip ...