Doo Wop BoxAmazon. com The unwritten rules for doo wop groups were deceptively simple: name your group after a bird (the Wrens, the Flamingos) or a car (the Cadillacs, the El Dorados), practice your two , three , or four part harmonies on a neighborhood street corner or in the back of a candy store, and sing songs about how much you love your baby. It might have seemed like an obvious formula, but getting it just right was never easy. When it worked, that