Vocal soloist quartet
Four vocal soloists who perform a part-song together, for instance in an oratorio.
What it means
A vocal soloist quartet consists of four vocal soloists who perform a multi-voice number together. The usual scoring is soprano, alto, tenor, and bass; combinations such as two sopranos and two altos are also possible.
Unlike a choir, each voice is sung by only one person, so every individual voice remains clearly audible.
Musical use
Soloist quartets appear above all in oratorios, Masses, requiems, and operas, usually alternating with the chorus and the orchestra. Examples are the four soloists in Beethoven’s Ninth Symphony or in Verdi’s Requiem, who repeatedly sound together as a quartet.
There is also the vocal quartet in chamber music for voices and in song; there it is often conceived as an independent ensemble without a choir.
The soloist quartet should be distinguished from the choir, in which each voice is doubled many times, and from the string quartet, which has the same number of performers but instruments instead of voices.
Performance practice
In a soloist quartet, fine mutual listening matters: adapt your intonation, vowel color, and volume to the other three voices. Agree on entrances and breathing points beforehand, since each voice is covered only once and inaccuracies stand out immediately.