The African American quartet is a tradition that was born in the mid- 1800s from singing that was done in universities by African Americans. The quartets are the earliest version of an a cappella group. This style of singing eventually transformed into a sub-category of Gospel music.
Quartet groups generally have between four to six members and they are almost always all men. The quartet will sing in a four-part harmony with little to no instrumentation. What makes the African American unique from the European style quartet is that the African American Quartet is determined by the number of harmony parts. The African American quartet broke into three different time periods: the jubilee period, the transitional period and the gospel period.
The Gospel period was when quartet music experienced the most amount of change. During this time more gospel songs and arrangements were being used. They also began to use more instrumentation which allowed for more voices to be added even though no more than six vocalists would appear at once. And as the performances became more demanding, eventually it became common place for quartets to have a soloist.
During this period, the soloists, or lead singers, began to experiment with their solos by including vibrato, falsetto, shouting vocals and timbre changes. And as gospel singers had already been doing, the soloists in quartets began adding personal testimonies and improvisation into their music.
Some of the more famous groups, and artists, of this period are the Pilgrim Travelers, Sam Cooke and the Soul Stirrers.
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