Surdo 1 & 2
The pulse and heartbeat of every samba band. Each drum is played with alternating beaters. Surdo 1 is tuned low and played on the first beat, Surdo 2 is pitched higher and replies with the second beat. These "bookends", with their energy and insistent driving rhythm, push the beat forward and provide a solid base for other patterns.
The mid-range sound, the melody drum. This smaller version of the Surdo, played with two beaters, is unique to samba-reggae. The dobra has a particular pattern for each of the pieces, the off-beat pattern featuring regularly, creating the reggae feel. The dobra plays complex patterns of drumming that combine space and notes.
Played with two flexi sticks, this drum helps call in the breaks and provides a "double layer" of clave to add to the snare. Probably 90% of the patterns played by the snare and the repique are the same. The difference is the sound made by the two sticks, lightening loud and snappy, like popcorn going off.
The snare gives the upper-range of sound, the "white noise" that fills in the spaces left by the other instruments. The snare is the drum that can play with the most nuance and expression.