Likutei Moharan 225:2/ליקוטי מוהר"ן רכ״ה:ב׳

12. And then, one can transform <all the tones>—i.e., the sound that emanates from the throat, which is nothing more than undifferentiated sound and <mere> tones—into speech, by means of the mouth’s five articulators, which enunciate speech.

2For the main difference between man and animal is the articulation of speech, this being the definition of man: he is a medaber (speaker). This is the aspect of “Who equipped man with a mouth?” (Exodus 4:11). The essential distinction is [in] the articulation of speech—i.e., that man turns the tone and <undifferentiated> sound into articulated letters and speech. For animals and birds also have sounds and tones, but they do not have articulation of letters and speech. This is <what distinguishes> human status—[man] is able to articulate speech, as explained.