Today, two percussion instruments are used in the rites of many of the Coptic churches: the small hand cymbals (Arabic: Daff), and the metal triangle (Arabic: muthallath, or colloquially turianta), each played by one of the deacons and/or the cantor. Providing a rhythmic accompaniment to specified hymns and responses sung by the choir and/or congregation, they signal the congregation to participate and unify the singing.
The hand cymbals are mentioned in both the Old and New Testaments (Ps. 150; I Cor. 13:1), which might be considered as a sanction for their use in the Coptic services. They were probably brought into Egypt from the Near East, but when they were introduced into the church is as yet unknown. They are a pair of slightly concave metal disks (usually silver) about 5-7 inches in diameter, with a cupped center 1 ¼ inch (3 cm) in depth. A hole in the center of each disk permits the passage of a string held in place by a wooden pin that acts as a handle for manipulating the cymbals. Throughout the hymn which they accompany, two movements of the cymbals characterize the beat: a diagonal sliding of the two disks against each other, and a circular motion of the two rims alternately against each other. Both movements produce a varied depth in tone. A trill of the rims with a final clap completes the rendition of the hymn.