Then I found another homepage with an interesting article about the history of the Viola Cabocla with some interesting pictures. This article was published in the Revista Sertaneja magazine during the 1950s.: http://www.widesoft.com.br/users/pcastro4/viola.htm
Finally the site of Eric Martins is also very useful if you want to learn to play the viola caipira – you can find chord charts and a basic method for the viola: http://www.ericmartins.mus.br/
The I have found that there are some big ensembles who play the viola caipira and sing. Those Orquestra de Viola Caipira sound very similar to a mandolin orchestra, they do also use the tremolo some times. Here is one example of such an orchestra:
Orquestra Paulistana de Viola Caipira
Finally I have found an interesting video that shows some steps of the making of a viola caipira in a small luthiers workshop:
I have just discovered some videos from Brazil with a viola caipira or viola sertaneja, an instrument with five double metal courses and slightly smaller than a guitar. You can find more information about those instruments in the Atlas of Plucked Instruments. The viola caipira is built like a normal guitar, the viola sertanejya is constructed like a resonator guitar (dobro / national). Another instrument with a resonator used in Brazil ist the Delvecchio, the Brazilian kind of a resonator guitar.
About the tunings of the viola you can read in the Atlas of Plucked Instruments:
There exist dozens of tunings for the viola, but often the tuning is open, for easy playing, like : aA d’D f’f# aa d’d’.
Roberto Corrêa, a viola master and researcher, said this about Helena: “She represented that border region of Paraguay, northern Argentina and Mato Grosso do Sul that culturally is a region by itself, replete with styles like the polkas, the chamamés, the guarânias, and the rasqueados. She brought the sounds of the frontier, of the wilderness, of an unknown place. Her way of playing was simple, but her music was not.”**
**from Jornal do Brasil, as quoted in Dicionário Houaiss Illustrado: Música Popular Brasileira (Rio de Janeiro: Paracatu Editora, 2006).
Helena Meirelles – Siriema / Água parada (Clodovil 1992)
Helena Meirelles – Guaxo
Then there are some videos with Milton Araújo who does also play the viola sertaneja. I found his video when I looked for a song named Araponga – I found his version of this song – it was not the song that I was looking for – but an interesting discovery. Before I add the Video with Araponga and his version of the Guaxo that he has obviously lerned from Helena Meirelles, her is a nice blues about Helena Meirelles:
Milton Araújo – Circuito Cultural
Milton Araújo executa seu arranjo de um Blues num especial sobre Helena Meirelles, exibido pelo programa “Circuito Cultural” (NET – ABC)
Presentes: Mário Araújo e Marcão (base);
Milton Araújo – Guaxo/Araponga
Milton Araújo no programa “Na Palma da Mão”, mediado por Gabino, executando do seu jeitinho especial “Guaxo” e “Araponga”.
E Marcão na booa base, como sempre!