The circuit of 5.1 Surround sound Decoder (audio  5.1/ Dolby Prologic), this circuit serves to convert analog signals stereo or 2-channel, into 5.1 ch. By using the non-digital decoder method, so this circuit processes analog signals with the IC Op-Amp 4558, so that signals that were stereo can change to 5.1 or 6 channels, namely Left, Right, Center, Rear Left, Rear Right, and Subwoofer. This circuit works with a 12V symmetrical voltage (12VDC CT). The following PCB Layout (Electro India) and its component list,