What is a surdo and what part does it play in samba?

The surdo is a large bass drum commonly used in samba music, particularly within Brazilian samba schools. It provides a deep, resonant foundation that drives the rhythm and supports the ensemble's overall sound. Typically played in a group, surdos establish a steady pulse that guides dancers and musicians alike, making it essential for the lively and energetic atmosphere of samba performances and parades. Its rhythmic patterns are crucial for creating the infectious groove that characterizes samba music.