passaggio
The transitional range between vocal registers where the voice must shift.
In Depth
The passaggio is the transitional zone between vocal registers — the point where the voice must shift from one mode of production to another. Most singers have two passaggi: the primo passaggio (lower transition) and the secondo passaggio (upper transition). Navigating these transitions smoothly is one of the central challenges of vocal training.
An uneven passaggio produces audible breaks, changes in tone colour, or loss of control. Through years of training, singers learn to smooth these transitions so that the voice sounds even and connected across its full range. The passaggio regions vary by voice type — a soprano's secondo passaggio sits higher than a mezzo-soprano's, for example.
Luciano Pavarotti reportedly spent years perfecting his upper passaggio, which is what gave his high C its legendary ringing quality that filled the largest opera houses.