lute known as a , guembri or , or , are central to Gnawa music. The has strong historical and musical links to West African lutes like the Hausa , a direct ancestor of the banjo. The rhythms of the Gnawa, like their instruments, are distinctive. Gnawa is particularly characterized by interplay between triple and duple meters. The "big bass drums" mentioned by Schuyler are not typically featured in a more traditional setting. Gnawa have venerable stringed-instrument traditions involving both bowed lutes like the and plucked lutes like the . The Gnawa also use large drums called in their ritual music. Gnawa players use a technique which 19th century American minstrel banjo instruction manuals identify as "brushless drop-thumb frailing". The "brushless" part means the fingers do not brush several strings at once to make chords. Instead, the thumb drops repeatedly in a rhythmic pattern against the freely vibrating bass string, producing a throbbing drone, while the first two or three fingers of the same (right) hand pick out percussive patterns in a drum-like, almost telegraphic, manner. Rituals Gnawas perform a complex liturgy, called or . The ceremony recreates the first sacrifice and the genesis of the universe by the evocation of the seven main manifestations of the divine demiurgic activity. It calls the seven saints and , represented by seven colors, as a prismatic decomposition of the original light/energy. The is jointly animated by a (master musician) at the head of his troop and by a moqadma or shuwafa (clairvoyant) who is in charge of the accessories and clothing necessary to the ritual. During the ceremony, the clairvoyant determines the accessories and clothing as it becomes ritually necessary. Meanwhile, the , using the and by burning incense, calls the saints and the supernatural entities to present themselves in order to take possession of the followers, who devote themselves to ecstatic dancing. Inside the brotherhood, each group (; Arabic: زريبة) gets together with an initiatory (Arabic: مقدمة), the priestess that leads the ecstatic dance called the (Arabic: جذبة), and with the , who is accompanied by several players of . Preceded by an animal sacrifice that assures the presence of the spirits, the all-night ritual begins with an opening that consecrates the space, the ("habit" or traditional norm; Arabic: عادة), during which the musicians perform a swirling acrobatic dance while playing the . The are abstract entities that gather a number