voice range between soprano and tenor in choral music
The musical term alto, meaning "high" in Italian (Latin: altus), historically refers to the contrapuntal part higher than the tenor and its associated vocal range. In 4-part voice leading alto is the second highest part, sung in choruses by either low women's or high men's voices. In vocal classification these are usually called contralto and male alto or countertenor.
Such confusion of "high" and "low" persists in instrumental terminology. Alto flute and alto trombone are respectively lower and higher than the standard instruments of the family, though both play in ranges within the alto clef. Alto recorder, however, is an octave higher, and is defined by its relationship to tenor and soprano recorders; alto clarinet is a fifth lower than B-flat clarinet, already an 'alto' instrument. There is even a contra-alto clarinet with a range B♭0 – D4.
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