In phonology and vocal art, a ballot box indicates the transition from a boy voice from soprano to tenor or bass.
A voice break (or breakup) usually occurs in boys in puberty when, under the influence of growth hormones, the vocal cords change shape and tension. Skiping the voice when singing from low to high can reveal a ballot.
The ballot box is therefore not a literal break of vocal cords, but a normal and common acoustic phenomenon. In vocal education, vocal training can be "camouflaged" during singing. Also see
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