It’s not the vocal cords that give a voice its richness, personality, or depth, however. Adele’s brassy beam of sound, Renée Fleming’s iridescent pianissimos, and Tom Waits’s smoke-and-whiskey croak all acquire most of their character after the vibrating air has pushed past the vocal folds and goes swirling around inside the resonating chambers of the head. Professional singers are often extensively trained, are highly skilled, and have a great sense of pitch and tone. They also rely on inherent singing abilities, such as a wide vocal range and nice vocal resonation. Singers are primarily self-employed and hired on a project basis, whether as consultants, performers, or judges in singing competitions.