Wah-wah effect Diverse sound characteristics Cabasa is made from durable fiberglass. The berimbau is a musical bow from the northeast of Brazil. In the south of the country, it is called urucungu. It is the main instrument of the Brazilian combat dance Capoeira. The thin striker and a caixixi are held in the right hand, while the left hand supports the bow and modulates the string with a small metal disc. The whole instrument is moved off-and-on the abdomen, opening and closing the resonant gourd, for a captivating "wah-wah" effect.