Requinto

The term requinto is used in both Spanish and Portuguese to mean a smaller, higher-pitched version of another instrument.

[2] Requinto can also mean a high-pitched flute (akin to a piccolo), or the person who plays it.

[3] In Galicia, the word may refer to a wooden fife-like instrument held sideways.

It was made popular throughout the 1940s by Mexican guitarist/vocalist Alfredo Gil of romantic music trio "Los Panchos.

[6] In Puerto Rico, there are many small instruments called Tiple Requinto.

In the absence of the arpa, the requinto typically introduces the melodic theme of the son and then continues by providing a largely improvised counterpoint to the vocal line.