Basso profundo

Basso profondo (Italian: "deep bass"), sometimes basso profundo or contrabass, is the bass voice subtype with the lowest vocal range.

While The New Grove Dictionary of Opera defines a typical bass as having a range that is limited to the second E below middle C (E2), operatic basso can be called on to sing low C (C2), such as in the role of Baron Ochs in Der Rosenkavalier. Often choral composers make use of lower notes, such as G1 or even F1, in such rare cases the choir relies on exceptionally deep-ranged basso profondos termed oktavist or octavist, who sometimes sing an octave below the bass part.

According to the Italian definition, any singer with an E♭2 in fortissimo is a basso profondo. Italian composers considered basso profondos as basses with "large" voices with a range of E2 to E4, lower than typical basses. Although a basso profondo obviously requires the ability to sing notes in a lower register, more importance is placed on the quality of "largeness," or resonance and sonority.

A historical reference of the basso profondo range was published in Jean-Jacques Rousseau's Dictionnaire de musique (1775), which states: "Basse-contres ~ the most profound of all voices, singing lower than the bass like a double bass, and should not be confused with contrabasses, which are instruments."

Russian composer Pavel Chesnokov divides the bass section into these groups:

Groups 5 and 6 are considered basso profondos.

An oktavist is an exceptionally deep-ranged basso profondo, especially typical of Russian Orthodox choral music. This voice type has a vocal range which extends down to A1 (an octave below the baritone range) and sometimes to F1 (an octave below the bass staff) with the extreme lows for oktavists, such as Mikhail Zlatopolsky or Alexander Ort, reaching C1.

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