Yamandu Costa (born January 24, 1980, in Passo Fundo), sometimes spelled Yamandú, is a Brazilian guitarist and composer. His main instrument is the violão de sete cordas, the Brazilian seven-string classical guitar. Costa began to study guitar at age seven with his father, Algacir Costa, leader of the group Os Fronteiriços (The Frontiersmen), and mastered the instrument under the guidance of Lúcio Yanel, an Argentine virtuoso, who lived in Brazil. At age fifteen, Costa began to study southern Brazilian folk music, as well as the music of Argentina and Uruguay.
https://en.wikipedia.org/wiki/Yamandu_Costa