The song of Common Diuca-Finch is described as a melodious, high-pitched succession of 4-5 notes, including underslurs in the middle notes, and most commonly with an accent on the final note: tiiup tweep chwuup TWEEIP (Jaramillo 2003, Perlo 2009). The song usually lasts between 2-4 seconds, with a mean of 3 seconds. The amount of time between songs is highly variable. The phrase tiiup tweep chwuup is a distinctive component of the song; in some areas, locals use the mnemonic tres chuachas y un diez (three green beans and ten) to describe the song (Bullock 1940).
A call is a sweet tweep (Jaramillo 2011).