The known vocalizations of Quebracho Crested-Tinamou are summarized by Smith et al. (2013) and Smith (in prep.). Vocalizations occur throughout the day, most often in the early morning and late afternoon, frequently beginning before sunrise and continuing after sunset (Smith et al. 2013). The species often sings at night (Steinbacher 1962).
Advertising call.— Most frequently heard at dawn and dusk (and only sporadically throughout the day), this is the most commonly heard vocalization. The Advertising call is a slow, descending double-whistled foooo-ip foo-ip, with the first part more drawn-out and occasionally a third, quieter foo-ip added. Singing bouts may last 30 or more minutes.
For a representative audio recording with sonogram, see audio
A variation or different dawn voice is fooouuu-ip fup-fup-fup-fup-fup-fup with a flatter succession of up to six final notes at rate of two per second. At dusk gives a variant foooo fp-fp (Smith et al. 2013).
Contact call?—A double or triple, falsetto fee-fee or fee-fee-fee, resembling a slightly lower version of the common whistled call of Purple-throated Euphonia (Euphonia chlorotica). Given most frequently in the middle of the day for short periods. Similar and perhaps analogous to that on Hardy et al. (1995). (Smith et al. 2013).
Alarm call?—An explosive, triple POO-IT POO-IT POO-IT, resembling the advertising call but with a more rapid and explosive delivery (Smith et al. 2013).
Roosting call.—At dusk a melodic liquid fLI-la-lu may be delivered 2–3 times with five-second pauses between each phrase, followed immediately by a somewhat lower pitched (by ca 1 octave) fLU-la-lu, also delivered up to three times. This is perhaps a sexually dimorphic, antiphonal duet, perhaps serving as a signal between birds going to roost. (Smith et al. 2013).
A single rising falsetto foo-WEE is of uncertain significance. (Smith et al. 2013).