The music of slavery refutes two common assumptions: first, that the Middle Passage stripped slaves of their African traditions; and second, that slaves were so powerless that they had little influence on American culture at large.
African American music under slavery retained many African elements. There was a striking continuity in instrumentation. Enslaved Africans either carried African instruments with them or reconstructed them in the New World. These included percussive, string, and wind instruments, from drums and banjos to the balafo (a kind of xylophone), the flute, the musical bow (a stringed instrument), and the panpipe (a tuned pipe).

When Lucy McKim Garrison, a nineteen year old piano teacher from Philadelphia heard the slave songs first hand in the Sea Islands in the midst of the Civil War, she was struck by how different slaves' forms of singing were from those found among European Americans:

It is difficult to express the entire character of these negro ballads by mere musical notes and signs. The odd turns made in the throat; the curious rhythmic effect produced by single voices chiming in at different irregular intervals, seem almost as impossible to place on score, as the singing of birds or the tones of an Aeolian harp (an instrument played by the wind).
Many aspects of later African American music trace their roots to the distinctive features of slave music. These include songs with such elements as intricate rhythm patterns, off key notes (or what are technically called blues notes, bent notes, and elisions), the incorporation of hums, moans, and vocables (sounds without a distinct meaning), foot patting, and a strong rhythmic drive. Among the distinctly African elements that persisted in slave music were irregular rhythms and tones, a rasping voice, a call and response pattern (with a leader improvising calls and the group responding), and a combination of sound and bodily movement.

Also, as in Africa, slaves used music for a wide variety of purposes. Music was incorporated into religious ceremonies and celebrations. It helped coordinate work. And music was used to comment on slave masters.

Slave music took diverse forms. Although the Negro spirituals are the best known form of slave music, in fact secular music was as common as sacred music. There were field hollers, sung by individuals, work songs, sung by groups of laborers, and satirical songs. Interestingly, there are no pre-Civil War references to narrative songs among slaves, suggesting that the blues ballad was a post-Civil War innovation.

Above all, there was a rich religious music. Shouts fused dance, percussion, and song and might last for hours. Singers formed a ring around which they shuffled. But it was the "sorrow songs" that were the most influential form of musical expression under slavery. Some slave songs were joyous and exuberant. Others were sorrowful. All were deeply expressive. Frederick Douglass would observe:

I have often been utterly astonished, since I came to the north, to find persons who could speak of the singing among slaves, as evidence of their contentment and happiness. It is impossible to conceive of a greater mistake. Slaves sing most when they are most unhappy. The songs of the slave represent the sorrows of his heart… At least, such is my experience.
Northern whites were largely unaware of the sorrow songs before the Civil War. But early in the war, after the Union army had captured some areas in Virginia and off the South Carolina coast, Northerners had a chance to hear this songs first-hand. In 1861, the Reverend Lewis C. Lockwood, who was in Fortress Monroe, Virginia, described one of the sorrow songs:

They have a prime deliverance melody, that runs in this style, 'Go down to Egypt—Tell Pharaoh/Thus saith my