At the beginning of the 20th century, three Cuban musicians formed Trio Oriental to perform the folk music that hailed from the west of the island. The trio later added members, changed their name to Sexteto Habañero, and became the first and most influential performers of son, a vivid Afro-Spanish fusion of musical styles. Son consists of two stylistic levels. The first level (African in origin) is a rumba rhythm over which a variety of percussionists improvise. The second level (deriving from Spain) is provided by a combination of three string guitars known as tres and a makeshift bass. Spanish lyrics are sung over the instruments in traditional decima form with rhymed octosyllabic lines. During the 1920s, Sexteto Habañero were the definitive son band of cuba. Their music is featured on two compilations: Cuban Counterpoint: History of the San Montuno and Cuba - El Son Es la Mas Sublime as well as The Roots of Salsa.