Researchers selected these pieces because they contain several changes in music dynamics—for example, crescendos, decrescendos, pianos, and fortes, etc, said Bernardi.

Tom Perchard, Hip Hop Samples Jazz: Dynamics of Cultural Memo y and Musical Tradition in the African American 1990s, American Music, Vol. 29, No. 3 (Fall 2011), pp. 277-307 ...