The Brazilian percussion importer Espirito Drums has this to say about the timbau drum.
Timbal (Timbau)A drum reportedly designed by Carlinhos Brown when he formed Timbalada, the band that bears the drum's name, the timbal is a similar concept to the West African djembe. However, the timbal is much lighter in weight and has a plastic head that keeps consistent tension in even the dampest weather. These drums are incredibly loud and can be heard even in a full bateria.
Attached are a few examples of the timbau patterns I use for quinto practice. I mix it up. I repeat one pattern several times or one pattern followed by another; creating improvised phrases from the memorized patterns. I've got three pages of these, but I'm only posting a few here. I've got to save some for myself, you know!