Samba
Although samba exists throughout Brazil – especially in the states of Bahia, Maranhão, Minas Gerais, and São Paulo – in the form of various popular rhythms and dances that originated from the regional batuque of the eastern Brazilian state of Bahia, a music form from Cape Verde, samba is frequently identified as a musical expression of urban Rio de Janeiro, where it developed during the first years of the 20th century. Early styles of samba - and specifically samba de roda - are traced back to the Recôncavo region of Bahia during the 17th century, and the informal dancing following a candomblé ceremony. It was in Rio de Janeiro that the dance practiced by former slaves who migrated from Bahia came into contact with and incorporated other genres played in the city (such as the polka, the maxixe, the lundu, and the xote), acquiring a completely unique character and creating the "samba carioca urbana" (samba school) and "carnavalesco" (Carnaval school director). Samba schools are large organizations of up to 5,000 people which compete annually in the Carnival with thematic floats, elaborate costumes, and original music.
Samba reggae
In the 1990s, the samba-reggae genre continued to evolve with the group Timbalada, which, under the musical direction of Carlinhos Brown, revived the nearly-extinct folk drum timbal (a tall, high-pitched hand drum) and begin to use it in stage shows. Timbalada also developed a rack of 3 surdos and 1 repinique that could be mounted on a stage and played by a single player. This device is known as a "bateria de surdo", a drumset of surdos. (The 3rd and 4th surdo parts were combined in a single drum.) Timbalada is a stage band and not exactly a Carnival street bloco, though they first appeared in the Carnival of 1992. Their music is considered to be a blend of samba-reggae with African elements. Many afro blocos now use the timbal, as well the rack of 3 surdos for stage situations that do not involve parades.