So I ran into one of my favorite things to run into yesterday. Mystery Surround Sound Decoder box. This thing looks homebrew or like a kit. The inputs say VCR so I'm guessing someone was using this for VHS surround. It has quadraphonic outputs. It is only marked with a silkscreen of "Surround Sound Decoder". The S's being a weird double S symbol. I don't know if that was intentional or a silk screening mistake. I did the first thing any good quad lover would do with it and open it up to see if there are any more clues. I was hoping the IC would give a clue but I think it is just a low power 4-channel amp chip. Does this circuit look familiar to anyone?