The song of Thicket Tinamou is described as "a mellow, slightly quavering [whistle] Whoo-ee-you!" (Sutton 1951); as "a resonant, hollow, whistled tuuuuu, often with a quaver in the middle, lasting nearly a second" (Stiles and Skutch 1989); and as "a loud, clear, hollow, fairly abrupt, 2-3 syllable whistle: hoo-oo op or hoo-oo-oo or hoo oo-oop'" (Howell and Webb 1995).
For a representative audio recording with sonogram, see audio
There may be some geographic variation in this song. The song of occidentalis, for example, frequently is upslurred at the end (Howell and Webb 1995).