Whispering

Whispering is an unvoiced mode of phonation in which the vocal cords are abducted so that they do not vibrate; air passes between the arytenoid cartilages to create audible turbulence during speech.

[5] In 2010, it was discovered that whispering is one of the many triggers of ASMR,[6] a tingling sensation caused by listening to soft, relaxing sounds.

This phenomenon made news headlines after videos on YouTube of people speaking up close to the camera in a soft whisper, giving the viewer tingles.

By sufficiently relaxing the definition of whispering, it can be argued any number of non-human species demonstrate whisper-like behaviors.

[9] In captive cotton-top tamarins, whisper-like behavior is speculated to enable troop communication while not alerting predators.