 Combining the sixteen bar structure and blues modes and rhythms with religious lyrics, Dorsey's compositions opened up possibilities for innovative singers such as Sister Rosetta Tharpe to apply their very individual talents to his songs, while inspiring church members to "shout" — either to call out catch phrases or to add musical lines of their own in response to the singers.This looser style affected other black religious musical styles as well.The most popular groups in the 1930s were male quartets or small groups such as The Golden Gate Quartet, who sang, usually unaccompanied, in jubilee style, mixing careful harmonies, melodious singing, playful syncopation and sophisticated arrangements to produce a fresh, experimental style far removed from the more somber hymn-singing.