The cuíca is a drum of friction and high tessitura, with sound generated by an irregular frequency of vibrations per second, which produces timbral intonations not aligned to the tonal system. It is an instrument that allows the diversification of the pitch of its intonations in order to build phrases and melodic adornments in the treble region. In its construction, the cuíca has a special rod, very thin, internally connected in its membrane for the articulation of the notes with the aid of a damp cloth. With the other hand, the instrumentalist presses the membrane from the outside using one, two or three fingers, modulating the pitch of the timbral intonations, which allows to obtain combinations of melodic phrases not aligned to the tonal system, in a high range. This intonation modulation property characterizes the cuica as an instrument with no similarity in percussion.
It is important to highlight that, according to author Luiz D’Anunciação, contrary to what some dictionaries inform, the cuíca and the puíta – also known as “roncador” – represent two instruments with opposite sound characteristics and musical functions, similar only in the physical aspect, as occurs for example with the viola and the violin in the string section of a symphony orchestra. Villa-Lobos emphasized this difference in his scores, which can be verified in Choros n. 6, where he demonstrated the different musical functions of the two instruments; the cuíca, with its high timbral intonation, and the puíta, with its low timbral intonation, assuming different roles in the same score.