Do the 7 mystery performers sing good or bad?

Jonas Van Geel, together with a five-member panel and a viewer duo, goes in search of the real singers, without hearing them sing.Presented with a group of seven "secret singers" identified only by their occupation, a duo of contestants must attempt to eliminate bad singers from the group without ever hearing them sing, assisted by clues and a celebrity panel over the course of five rounds. The duo must eliminate one singer at the end of each of the five rounds. Will they end up with a good singer or a bad singer. All will be revealed in a duet with the guest famous singer and the last 'secret singer'.