Gimbri

The sintir (Arabic: سنتير‎‎), also known as the Guembri (الكمبري), Gimbri or Hejhouj, is a three stringed skin-covered bass plucked lute used by the Gnawa people. It is approximately the size of a guitar, with a body carved from a log and covered on the playing side with camel skin. The camel skin has the same acoustic function as the membrane on a banjo. The neck is a simple stick with one short and two long goat strings that produce a percussive sound similar to a pizzicato cello or double bass.

The goat gut strings are plucked downward with the knuckle side of the index finger and the inside of the thumb. The hollowed canoe shaped wooden body resonates a percussive tone created by knuckles slapping the camel neck top of the body while the thumb and index finger are plucking the strings.The lowest string on the sintir is a drone note and the second string, the highest in pitch, is tuned an octave higher and is never fretted. The third string is tuned a fourth above the drone. The buzzing sound often heard emanating from the sintir is caused by metal rings dangling off of a galvanized metal feather mounted on the end of the sintir's neck. The feather and rings vibrate in rhythm with the sintir.

The body of the instrument is hollowed out from a single piece of wood, and covered with camel skin. The long neck passes through the top of the body and runs under the face, coming out through the skin near the base of the instrument, to serve as a tailpiece or string-carrier. The sliding leather tuning rings and the rattle-like metal sound modifier are commonly found in such West African instruments as the kora and the xalam (lute). The percussive playing style is reminiscent not only of West African technique but also of certain styles of American banjo picking.

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