The most popular percussion instrument in Persian music is a goblet drum known as the tonbak, a large wooden instrument with a goatskin head. Unlike other goblet drums, this drum has a squared-off shape and produces soft, low-pitched tones, due to its size and the low tension applied to the head. Other names for this drum are donbak, tombak, dombak, and zarb. The two main strokes played on this drum are known as ton (a bass tone played in the center of the drum head) and bak (a treble tone played on or near the rim). Combining the terms results in the name Tonbak.