Contralto

A contralto (Italian pronunciation: [konˈtralto]) is a type of classical female singing voice whose vocal range is the lowest female voice type. The contralto's vocal range is fairly rare; similar to, but different from the alto, and almost identical to that of a countertenor, typically between the F below middle C (F₃ in scientific pitch notation) to the second F above middle C (F₅), although at the extremes some voices can reach the E below middle C (E₃) or the second B♭ above middle C (B♭₅). The contralto voice type is generally divided into the coloratura, lyric, and dramatic contralto.

"Contralto" is primarily meaningful only in reference to classical and operatic singing, as other traditions lack a comparable system of vocal categorization. The term "contralto" is only applied to female singers; men singing in a similar range are called "countertenors". The Italian terms "contralto" and "alto" are not synonymous, the latter technically denoting a specific vocal range in choral singing without regard to factors like tessitura, vocal timbre, vocal facility, and vocal weight.

A true contralto is often regarded as the rarest of the female voices, and is present in as few as one percent of the population. Some vocal theorists have found that the vocal folds are thicker than those present in other female voices. Studies have used cameras to photograph visible differences which are also found in countertenors.

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