A speech sound or series of speech sounds that symbolizes and communicates a meaning usually without being. Some, like bang, have already acquired word status and their orthography and meaning is fixed. An answer for which i do not have a source, but is worth consideration, is that the sound shhh is soothing to babies, perhaps because it imitates the sounds in the womb.
Khhh shhs hshh shhh 希望能帮到你们,这个要经常练习,beatbox不是一两天就能学会的,基础三音很重要,就算学会了,每天还是要练习一下,因为这个beatbox少不了的节奏! Onomatopoeia can be more or less conventional. I know i could say shush, but there are times when i really have to say shshshshsh.
What would be the best way of writing this.