Several audio recordings have been made of Angela Davis's speeches, including the one above.

From the artist's statement: "The piece opens with an introduction by Cornel West, taken from his participation in the 1997 Du Bois forum "A Conversation on Race"...the listener will discover that the words "Hey Angela!" are assembled from syllables sung in the original songs (Angela by John Lennon/Yoko Ono and Sweet Black Angel by The Rolling Stones.)"

Link to an archive of the original contest announcement.