  Whistled speech is a little studied local use of language shaped by several
cultures of the world either for distant dialogues or for rendering traditional
songs. This practice consists of an emulation of the voice thanks to a simple
modulated pitch. It is therefore the result of a transformation of the vocal
signal that implies simplifications in the frequency domain. The whistlers
adapt their productions to the way each language combines the qualities of
height perceived simultaneously by the human ear in the complex frequency
spectrum of the spoken or sung voice (pitch, timbre). As a consequence, this
practice underlines key acoustic cues for the intelligibility of the concerned
languages. The present study provides an analysis of the acoustic and phonetic
features selected by whistled speech in several traditions either in purely
oral whistles (Spanish, Turkish, Mazatec) or in whistles produced with an
instrument like a leaf (Akha, Hmong). It underlines the convergences with the
strategies of the singing voice to reach the audience or to render the phonetic
information carried by the vowel (tone, identity) and some aesthetic effects
like ornamentation.
