Diverging patterns in mode’s associations with other musical cues carry distinctive expressive connotations. The major and minor modes’ relationship with loudness and timing are often understood in absolute terms, with major pieces described as being faster and louder than their minor counterparts. However, recent findings suggest mode’s relationship to other cues shifted markedly in the Romantic era (Horn & Huron, 2015). Here we expand on previous work using cluster analysis to track expressive changes in music history, applying this technique to Bach’s *The Well-Tempered Clavier* (1722) and Chopin’s *Preludes* (1839). Analyzing clusters of each composer reveals empirical support for mode’s changing expressive associations. Specifically, Chopin’s minor pieces are distinguished by fast attack rates and louder dynamics than Bach’s, consistent with research highlighting mode’s changing musical meaning. In tandem with our team’s work performing perceptual experiments with these pieces, this analysis provides a valuable complement to the small but growing body of research exploring changes in the use of emotive acoustic cues over musical history.